So what did they think?

I just got one of these myself to begin experimenting with (not part of the study).

So far VERY interesting...

I've done the following so far with it
1 x 2:45 long run outside
1 x 30 min easy treadmill run
1 x 90 min endurance ride

i'm looking forward to the improved integration into Training Peaks and looking forward to seeing what the testers have had to say!

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Merge Multisport Founder & Head Coach
USAT Level 2 - Short & Long Course
Ironman Certified
Brevard, NC

I was one of them:

Bottom line up front: First of all it works as advertised. It's small, unobtrusive, and easy to use. The data is quite handy to and easy to understand. The ramp test is easy to do. I used it as a decision making tool.

I live in a hot and humid environment where the dew point stays high enough in the summer that sweat will not evaporate so while I get hot I'm always wet meaning I can't really tell how hot is "hot" until it's too late. This is especially true on the bike and where I get the most benefit from the Core.

I can see the Core data on my Garmin 530 and the data screen is pretty simple. (I like simple). On "hot days", like I said that is almost a constant where I live, I have seen my core body temp reach 103.5 F on the bike and 105F running. More on running in a little bit.

On the bike without Core I know it's hot but I have been fooled by the wind and the breeze generated by riding thinking that I'm not that hot until my performance declines and I don't know why. However with Core it takes the guess work out. I know when I have to use cooling strategies while riding now, dump water over my body, grab some ice at a stop, etc. because Core gives me a number. Being proactive in cooling has increased my performance or in other words decreased the debilitating effect of the heat.

Running is a different matter. Prior to the Core I had to use feel for the heat and HR. When sweat doesn't evaporate it's super hard to guess how hot you are. With a lot of training you can figure out the effect of heat on your HR but there is still a little guess work there. Core gives you a number, tracks histories, and you can see trends. Its a simple processes on my Garmin 945. Before Core I would go by HR and feel. I sweat, I'm wet, I feel ok, so I must be ok until the wheels come off. Now I know when to use a cooling strategy proactively.

The device itself, phone app, and widgets on my two Garmin's are all easy to use. It complements the other data that I track and again it takes the guess work out for me.

For me (and yes, this part is personal) the biggest win for the Core is on the bike. Its really good to know how hot I'm getting and watch the numbers go down when I cool. Its a good mental check for me other than telling myself "This heat sucks". I'm no longer fooled by the conditions. Running is just hard in the heat period and you can only cool so much and keep running. Core is super handy in that endeavor but on the bike, at least for me, it's become essential.

Ok, so this isn’t a cooling device….it’s a monitoring device??

Anything you can say you'd do differently in training based on what you saw?

I started a pretty novice topic on here a year ago or so asking about heat adaptation and also optimizing gains from training. So, basically trying to pinpoint what power zones to train in hot and which to train in indoors or optimally cool like early morning.

Consensus I thought I got from asking that was lower zones when hot and threshold area zones when optimally cooled.

Funny though how it works out that all my free time from family stuff it winds up being that weeknight worlds is super hot or my free time for cooler rides in the AM on weekends is when I can get in more time instead of more intensity. Exact opposite of how I'd prefer it.

Ha... I just ordered based on this thread. Score one for ST driving revenue for Core. I am a sucker for cool tech devices. Plus, I live in a hot & humid climate, and I really want to objectively know how my core temperature is affected by tough conditions and in turn how both correlate with performance.

Very cool! Can’t quite justify the spend, given that HR, wattage (or run pace), RPE, and the occasional post-workout thermometer probably get me close…but let me know if CORE needs Kona guinea pigs. Would love to try it out.

Interesting and useful commentary. I’m on coastal SE USA and have the same issue as the lows will not drop below 75 for the entire summer with a ridiculous dew point. I’ll wait for a few more comments but I’m leaning heavily towards buying one as I’ve been curious about it since hearing Kevin Poulton on various podcasts discussing the product.

I certainly understand being wet and not knowing you’re on the ledge until it’s too late. I’m 6’2, 168 prior to any weight loss and on Sunday I went out for my long 13 mile easy run - it felt cooler than normal, and technically it was, I stopped halfway at just short of 50 minutes and had 16oz of precision hydration. Finished the run and had a 20oz Gatorade on the drive home - shower, get on the scale and boom - 157lbs. That sweat loss is typical for me, but this time it didn’t feel like I’d lost much - I had no idea how close I really was to doing the walk, jog, sit under tree, repeat process.

What actionable items come from it? Or just the nice feeling of knowing you’re getting hot? Have you found anything like a 30sec walk break gets temp down?

Interested to hear more how you use it.

Also - chest or arm? Website makes it sound like chest is preferred but they sell an arm strap. I haven’t worn a chest strap in years.

Correct. Just like a HR strap monitors your HR.

Acclimating to hot conditions has always been an intriguing part of triathlon given our crown jewel event takes place in Kona, Hawaii. The first time I qualified to race on the Big Island was in 2003 and was living in Minnesota. I scoured the forum to see how others living in cooler climates prepared for the heat and humidity of Hawaii (trainer in enclosed room with air heater blasting, multiple layers of clothes, sauna, etc).

Fast forward 18 years, I was ecstatic to learn there was a device like CORE to measure body temperature, and in a simple way, not by having to swallow a pill or sticking a thermometer up the backside (neither of which I would be willing to do, for the record). The device clips onto a heart rate monitor band to be worn on your ribs under your armpit.

Why is heat training important? Yes it helps you perform in hot environments but heat training also helps trigger an increase in blood volume and plasma. According to one of the many cool blogs on CORE's site many of the top coaches they work with suggest 101.3-F is the ideal body temperature to trigger this physiological benefit.

The first thing CORE suggests you do is perform a Heat Ramp Test (somewhat similar to a FTP Test). CORE suggests you do this in a somewhat old fashioned way, on the trainer wearing layers of cloths and without fans for cooling, in order to more quickly pinpoint when the body temperature hits 101.3-F at which time you could determine a Heat Training Zone of between 101.1-F - 101.5-F for subsequent training. This test was uncomfortable but is not nearly as difficult as a FTP test.

Once a Heat Training Zone is established, CORE suggests a 2-4 week dedicated heat training block followed by adding in 2-4 heat training workouts into your regular training in order to retain those adaptations.

I've been living in The Woodlands, Texas (NW of Houston) since 2013 and conditions are nearly always hot and humid. In much the same way those living at altitude experience physiological benefits, I noticed the same training in the heat, though I had no way of measuring or monitoring, only what I perceived. Using the CORE has given me insight into my body temperature at various efforts and how that correlates to other measurements like heart rate and power too. For me, this has become a far more useful number to keep an eye on, as once body temperature climbs past a certain threshold, performance is guaranteed to suffer.

The only downside I experienced was having some initial difficulty connecting the CORE device to my Garmin device, though I am a luddite so this was likely a "me problem". Once connected though, it was easy to use. Keep in mind out of the box the device takes 4+ hours to fully charge, so don't expect to use it directly after opening.

While I have rarely worn a heart rate monitor or used power in years I will continue using this CORE device as a key metric during training and racing.

Happy to answer any specific questions anyone has.

Lars

The answer is yes. Zone 4-5 workouts in the heat is really hard to do and cool. Zone 2 is much more doable and easier to manage but with Core you can figure this out with a number vs feel. And of course my training time availably is like yours.....is always hot during the weekdays when I get off work.....sadly.

Ditto, and why I ordered just based on a few. Most of my runs are ~75° F and at least 90% humidity. My 70.3 runs are typically above 80° and 80%. Saturday I ran a race that was 98% humidity. I can usually wring a small puddle of sweat from my shirt after a run.

I want something that can help me objectively correlate how I am feeling to run performance and my nasty summer weather. So, rather than waiting until I feel super crappy and slowing down involuntarily, I am hoping that this can show me core temperature trends early so that I can back off, hydrate, or pack ice sooner than I might ordinarily and preserve a strong finish.

We must be the same person. I'm 6'2, 167lbs and ran 13 miles last weekend. Heat index was 103....it sucked. I lost 5.7lbs during the run and that was drinking a lot. I live in the SE USA so from June-Oct it's hot and humid 24/7.

I think that's the whole question mark...what actionable items are there to take?

first off it shows me that even trying to run at a very low HR outside in the current climate, my core blows up. So my legs don't get the mechanical loading / stimulus I want for training...so time to go inside to get that load.

I'm hoping to see that I can take structured walk breaks along with ice / cooling towel and can keep my core temp down. but at 102.2 I was done. my Hr very quickly went from staying under 140 up to 160 as the temp climbed over 101.6

---

Merge Multisport Founder & Head Coach
USAT Level 2 - Short & Long Course
Ironman Certified
Brevard, NC

I was also part of the Slowtwitch team, and was quite honored to be included in this cool review. Pairing the CORE was relatively easy through Garmin ConnectIQ, and I got it set up as a new data field on my watch and bike computer. The device slides onto a HR strap with a couple of clips or can also be worn with included patches. I've only used it on my HR monitor strap. Once it's on, you don't notice it's there while working out.

I live outside of Boston, and while we don't get the sweltering heat of other parts of the country, the humidity is often very high. My first race of the season was Eagleman, and I was interested to see what my internal body temp was during the race. I got the CORE a couple of weeks prior to the race, so I was able to test it out a bit, but I didn't do the heat ramp test prior to the race. One thing that the CORE validated for me was that once your core temp is elevated, it is pretty hard to reduce quickly. It's not like HR, where easy spinning or coasting down a hill drastically lowers HR. Your core temp may go down .1 degrees F on a 2-3 minute downhill without pedaling. Having this metric and getting to know your temp zones is definitely great for racing. I think many of us have gone past that point of no return, sometimes without realizing it, and the internal temp gets too high to do much of anything. The CORE allows you to monitor your temp and back off a bit to try and stabilize your internal temp on hot days.

As Lars mentioned, the heat ramp test isn't nearly as draining as an FTP test. You essentially eliminate any cooling and ride inside. I wore winter attire - tights, socks, jacket, hat & gloves. The basic idea is that once you hit 38 degrees C you try to hold your HR constant for a period of time. Over time, your power begins to drop as the heat builds up, and eventually you reaching a stopping point. For me, I got to just over 39 degrees C or around 103 degrees F. There is no specified time limit like 20 minutes in an FTP test - more of you know when you are cooked (kind of literally). Then you can go back and look at the data to find your heat training zone for acclimation.

Getting back to the race at Eagleman, unfortunately I crashed coming out of T1 - completely my own error. At that point my core temp was right around 103 degrees. As a result of the crash, I smashed my lower left leg and was unsure of how the rest of the race would go. My power was 30-40 watts lower than planned because of the crash, and this led to my temp dropping over the course of the bike. Down to around 101.8 at the end of the bike. The run was a hobble due to the crash and my core temp pretty much stayed constant a bit under 102. Race conditions were perfect for Eagleman, with cooler temps and lower humidity than normal. I wish I could have seen how I could have gone without the crash, but it was good to see that backing off a bit does get the internal temp down to a lower level.

I've been using CORE on pretty much every run and ride since Eagleman, and I really feel that being able to monitor internal temp is extremely valuable for any training or racing in hot/humid conditions. Having another metric that you can get to track over time to pair with HR and power allows me to begin noticing trends. As I've built back into the training and am getting a bit more heat acclimated I'm noticing that the CORE is giving me slightly lower internal temps at running paces and power compared to a month ago. I've also noticed that even with fans inside, the body temp gets elevated more rapidly than outside. This is kind of a no brainer, but being able to track and monitor the internal temp can help make indoor training even better.

I'm racing in St. George in September, and I definitely plan to do several of the heat acclimation sessions. The gym I belonged to that had a sauna closed during the pandemic, so that isn't an option. I'm happy to try answering any specific questions others have.

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Blog: http://262toboylstonstreet.blogspot.com/
https://twitter.com/NateThomasTri
Coaching: https://bybtricoaching.com/ - accepting athletes for 2023

This is very useful, thanks Nate and others for contributions so far.

Prior to reading this I was curious if anyone had done any sort of protocol, be it sauna, cycling with no fans and extra clothes, etc and could measure a before and after difference. Apparently you’re seeing that. Much appreciated

Excuse my ignorance as I'm not very strong in human physiology. I believe a person's HR increases when their body temperature increases to carry more blood to the skin for cooling. I'm assuming wearing a HR monitor is a lagging metric, i.e. the core body temperature has already increased and what this device provides is an ample warning that action needs to be taken to reduce your core temperature before the HR increases and you bonk. Is that correct? Were you able to study and quantify an approximate time lag between an increase in body temperature and HR increase? On the order of tens of seconds or minutes? Everyone's different but it'd be nice to have a range of what was observed, if any.

If it can be integrated with Garmin devices, I assume you can set it up to alert you at various temperatures...is that correct? Thanks.

Wow! How many minutes was the run? 11 lbs + 1.25 lbs + 1 lb = 6 kg. Assuming you were under two hours, your either not far from a world-record sweat rate (unlikely, given that it was an easy run), or there’s some measurement error.

As a fellow sweaty guy, I feel your pain. Wishing us both good luck and no hyponatremia!

If you include the water/precision hydration stop, run was around 1:45 - run time of 1:42. I’ll say the time to scale also included a 15 minute drive home and shower where additional perspiration definitely occurred.

And while I’ve never had it measured in a lab, I’ve had some pretty big problems over the years with heat in both races and training. To the point that this spring I purchased a pvc sauna suit to not only race prep, but also make the onset of summer more tolerable. I also have a treadmill arriving Thursday as i finally crossed the point of being tired of having everything in the summer be a game of hydration catch up.

ETA: unfortunately not a measurement error. I actually wasted $ on a Garmin scale last year because I didn’t trust the #s on our other cheap digital scale - now I have 2 sources of truth, unfortunately.

With the clip to HRM strap option, is there anything consumable about the device? Or are the pads only consumables if you go with the stick on route?

Ordered!

Same. Will deal with the wife complaining about more purchases whenever she sees it.

Nothing consumable if you put it on a hr strap.

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Blog: http://262toboylstonstreet.blogspot.com/
https://twitter.com/NateThomasTri
Coaching: https://bybtricoaching.com/ - accepting athletes for 2023

Agreed. Can someone spell this out to me like I'm 5? Not looking for examples of what can be learned about individual responses, but actionable training changes that might lead to predictable results.

Looking for "if X happens, do Y, to achieve Z", "if A, do B to get to C faster", or "if D, then you know E"

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Dr. Alex Harrison | Founder & CEO | Sport Physiology & Performance PhD
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📱 Check out our app → Saturday: Pro Fuel & Hydration, a performance nutrition coach in your pocket.
Join us on YouTube → Saturday Morning | Ride & Run Faster and our growing Saturday User Hub

Yikes, 3L per hour is impressive. Out of curiosity, have you ever done an IM? If so, do you recall what you did for nutrition? How’d it go?

I’m struggling to understand how us sweaty folks can physically compete for 9+ hours (longer for me) without slowing to a crawl.

Not since wide use of power, sharing of training data, nutrition info, etc has become prevalent. I was signed up for Copenhagen 2020 due to trying to play to my strengths (I.e. not ridiculously hot/humid) and I wanted a KQ, but a 2021 IM isn’t in the cards due to work.

For 70.3s I use precision hydration on the bike and base salts on the run.

One application I could definitely use this for is heat acclimation; in particular, lowering risk of heat stroke. For example, the last heat session I did raised my temp by more than 2.5 degrees C. I think you only need 1-1.5 degrees to get the benefit. If I’d had this device, I could have backed off.

Not to be a contrarian, but sometimes we can get lost in metrics and metrics can thwart our efforts. Every now and then I forget my devices and when I do, i find my overall performance seems to go up when purely based on perceived exertion. I think sometimes staring at my heart rate and watts tells me I am at my limit and cant last and that becomes a self fulfilling prophecy. I love metrics and devices but I think we should all remember to splice into our workouts efforts which are naked.

What useful data do you find the device gives you that can’t already get from other existing tech (HR, power etc)?

The CORE device monitors your body temperature.

The most applicable use would be during a heat training block. By knowing your core body temperature you can figure out pacing strategies and how to cool yourself as best as possible to keep your internal temperature down and hopefully avoiding implosion!

With the proliferation of e-racing on Zwift, etc I can see a benefit to wearing it during indoor workouts too where it's easy to overcook oneself.

I’m far from a scientist, and neither is Kevin Poulton, but look him up on several podcasts and maybe some papers online as well (although not certain what’s out there beyond podcast land). I’ve got some general ideas of how it may help an excessive sweater not dig a hole while living in excessive heat and humidity (meaning n=1, myself), and I’ve got a hypothesis but I’ll wait until next year to share IF it works. I’m mainly hoping to strike a balance with indoor and outdoor training that keeps me adequately heat acclimated for where I live, but not dig a hole from doing everything in the heat/humidity. I generally don’t race in the summer because it’s hard to do much quality outdoors, and I’ve also botched preparation for fall races because of likely chronic dehydration and over exertion in the heat leading to being worn down and injured.

Basically, I’m hopeful. I also think there will be more coming out on what people have done once the olympics are over that may provide useful. If not, it’s $290 USD so no big deal.

i'll make sure to check out that podcast you recommended.

some insightful posts already from the Norwegian Tri Team on their use of CORE in preparation for Japan's heat, including how they selected their race kits. HERE is a link to that blog post.

ROFL!!!!

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"see the world as it is not as you want it to be"

I was part of the group that used the Core device to monitor body temp. For this I found it nice as I typically have an epic meltdown yearly due to the Tucson heat.
Right now, to give you an idea of the Tucson climate it's very similar to east coast with temps in that 96-104 range, humidity in the 60-70% range and a high dew point. The dew point is usually ~ 2F cooler than my DC athlete's dew point during monsoon season whenever I check.

First the downside. I found that the app often had large gaps in the data on ~ 80% of the rides I did. This happened indoors or outside. You can move the screen to your garmin. I struggle to see what's on there as it is and one more data field would have shrunk everything more. It's easier to pull my phone out between intervals, leave the app open when riding indoors or go home and look at the app post ride. You can go online and see what happened as the device is always recording but it was a bit frustrating to be doing intervals, watch your temp climb on the first group of intervals, check the screen on your recovery in the second group and realize that the app hasn't shown core temp for the previous 20 minutes. That is my only frustration with the device.

A few of you asked for answers/actionable items. And this is where the device shines.

If you're someone who typically struggles in heat you can mostly monitor your core temp in real time.

ok so great, but what does that mean for me?

As you do intervals, the environmental conditions get more extreme, your ride goes on in duration etc you'll learn where your danger point is. Where is the inflection where body temp increases above a certain point and you crater? If you know that's say 101.7 and you see your core temp getting close to that, you can make decisions.

Above that inflection you blow up, below that you're doing fine to ok to degrading performance as you get closer to that temp . Now if you're in a workout and you see your core temp get close to that point then you know to back off, increase cooling mitigate the increase in some fashion. The take away is that you have a real time device telling you when you get near or in the danger zone. Most applicable to short intense sessions, long rides/runs, interval sessions & of course racing bc who wants to blow up there?

Going 10w slower on the bike may cost you 5 min in the bike leg but how many minutes is shuffling the last 10k of the run costing you? With the Core device you can monitor that as you race/ride/run then make the decision to push, drive your core temp past that point and hope you hit the finish line before melting or back off and hit the finish line probably in a much faster overall time compared to blowing up.

The second actionable item is you can implement a heat training protocol in your training and monitor if that point where you meltdown is increasing. Maybe it goes from 101.7 to 101.9 before you crack like an egg. When it comes to key workouts or racing now your margin of error has increased. If you don't have one of these you have to cross your fingers & hope that your heat tolerance protocol is effective.

The third place it's useful is how fast does your core temp ramp up as you increase intensity and which intensities/ % of FTP drives it up the most and how fast. We all know that doing vo2 work is going to increase heat produced/internal temp faster than tempo work.

How fast does a long tempo block drive up your core temp? What about a vo2 block? You get real time data on this stuff. Great you're thinking, how can I implement this?

Let's say that you realize riding ~85% causes a long but gradual increase in temp but you never get to that break point or rarely and that 106%+ of FTP causes you to spike your core temp rapidly. Now you can look at the weather and then tailor your intervals based on that. If it's an above normal temp day/higher than normal UV index day maybe you don't go do vo2 intervals and you do tempo intervals instead. This could allow you to get the same kJ of work done. Where as if you tried vo2 intervals you may have blown up after the first third of your set bc your core temp went to high.

If you guys have questions I'm traveling the rest of the day, will circle back tomorrow afternoon to answer them.

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

Brian,
Thanks for that detailed response. I think this has a lot of promise. I hope to hear of some protocols folks are using and maybe see some literature come out on it.

In the meantime, I suspect I have a couple data-nerd clients that may be interested in the next year or so. For the bulk of my clients, just managing power meter, HRM, head unit, syncing and uploading training is probably enough for now. lol

Does this display as a new field on TrainingPeaks? If so, how. Could be interesting for me to use as a coach if it becomes a pretty streamlined process of interpretation like power/cadence/speed/HR etc have.

---

Dr. Alex Harrison | Founder & CEO | Sport Physiology & Performance PhD
-------------------------------------------------------------------------------------------------------------------------------------------------
📱 Check out our app → Saturday: Pro Fuel & Hydration, a performance nutrition coach in your pocket.
Join us on YouTube → Saturday Morning | Ride & Run Faster and our growing Saturday User Hub

So helpful. Thanks for this post, Brian.

[quote desert dude
First the downside. I found that the app often had large gaps in the data on ~ 80% of the rides I did. This happened indoors or outside. You can move the screen to your garmin. I struggle to see what's on there as it is and one more data field would have shrunk everything more. It's easier to pull my phone out between intervals, leave the app open when riding indoors or go home and look at the app post ride. You can go online and see what happened as the device is always recording but it was a bit frustrating to be doing intervals, watch your temp climb on the first group of intervals, check the screen on your recovery in the second group and realize that the app hasn't shown core temp for the previous 20 minutes. That is my only frustration with the device.[/quote]
Great post. A couple of questions.

1. Surrounding the part I quoted - when I ordered I received an response indicating to put the monitor on 20 minutes before workout to negate this type of thing. Did you try that? And If so, did it matter? To that end, have any of their updates they’ve pushed out improved performance?

2. Surrounding the 101.3 to ~101.7 or .9 I’ve seen in multiple places. I’m failing to recall where that comes from? I assume if you do whatever ramp protocol you’re going to find that spot on your own?

Thanks all for the commentary here!

I was one of them too! Just a bit of background, I’m not a data nerd, I’m not obsessed with the numbers, and not a technical expert, so offer the “simple” feedback.

Where I found this helpful was in understanding the impact of a workout. There were some workouts that I struggled with, or found I took longer to recover from - these are where my core temperature went higher than at other times. Texas summers are hard to control, but I’m doing these sessions again I’ve been able to identify more effective cooling strategies or recovery strategies which will allow my training to be more effective and also help in racing in heat. Having this data helped me learn more about my “feel” and make more specific or informed choices during training or recovery.

Core temp awareness I see as another piece of the jigsaw puzzle, as all things data is only as good as your understanding of what to use it for. Living in South Texas I have found I’m coping better training in the summer heat so that’s a huge bonus.

It was super easy to set up, and use.

I have been one of the testers as well! I am currently living in the hot & humid Woodlands, Texas where I have moved to almost 3 years ago from Boston, Massachusetts. I wish I had CORE back then, because I will never forget just how horrible I felt the first few weeks of trying to train during the Texas summer. It would be interesting to see the difference between back then and now.

As others mentioned, CORE is very easy to use and although I was a bit hesitant going back to wearing a HR strap, it has been a non issue at all. I do wish the battery itself lasted longer as there has definitely a few times I would forget to recharge it, and not realize until it was too late.

During this testing period, I have been using the CORE to collect data during sessions rather than guide my sessions . As an avid user of both power /HR on the bike and STRYD power/HR on the run, it’s been great to see how my body temperature correlates with both, and I’ll definitely be using CORE data to guide my pacing strategy come the IM world championships.

While I found my body temperature to be quite similar on most training days, I was quite surprised what happened when I wore my CORE during Lubbock 70.3 last month. Lubbock is known to be a very hot race, that always ends up with a wetsuit legal swim, and this year was no different most likely due to the crazy storm that rolled in the night before race morning. The air temp was actually only 66 degrees at the start (87%) humidity, which is quite cooler than what I am used to training in at home or what Lubbock usually dishes out. I wore my CORE during the swim, and although you can’t measure your core temp while swimming, the second I took my wetsuit off, my core temp readings were available. And here is the surprise. Though I didn’t feel hot, my core temp at the start of the bike was already higher than it was during any training session including 3-4 hour outdoor bike rides or double digit runs in much higher temperatures.

Don’t get me wrong, I love wetsuit swims, but perhaps this is something that Ironman may want to look at when deciding just where to measure pre-race water temps. I didn’t necessarily feel hot while riding so I didn’t utilize aid stations to cool my body (remember – I was only collecting info not being guided by it), but this would explain why I struggled to put out my usual 70.3 power during the race. Even though my core temp lowered a bit throughout the ride thanks to my lower than usual power output, I still ended up with the highest core temp ever over just a 2 hours and 16 min of riding. The trend continued on the run, and even though I was trying to cool my body down at each aid station, I found it quite difficult to actually lower it. You bet, I will be paying close attention to my core temperatures out of the swim in the future.

I look forward to using CORE in my prep for Ironman World Champs in October, and would also love to see the data incorporated into TrainingPeaks in the future.

you beat me to this question.

can this data be dumped anywhere and easily tracked? is it just in the app (that one of the st testers said was a bit buggy)?

the data is great and all, and i fully believe it can be very useful, but being able to go track it easily makes it a much better tool.


also... can we get a discount code? :-D

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80/20 Endurance Ambassador

I was also one of the testers for the Core Body temp and have used to track core temp in my training as well as using it to track that of a few of my athletes for the 6 weeks or so.


The device is very easy to use with a regular HR chest strap (you don’t notice it) but can be use with an arm band. The app is easy to use and you pair it with Garmin and Wahoo. For Garmin there is a Connect IQ app for the Core which lets you track core body temp and save all the data in the .fit file so you can do simple analysis in something TrainingPeaks as a scatter graph or in more detail in something like WKO5. For instance, you can track your core and skin temperature through a ride/run and dissect the data further comparing to power or other as you wish.


For Wahoo though, they don’t have a native setup (yet) so as a work around you can use the muscle oxygenation option and connect the core that way. It will show core temp in C or F so makes it easy to track while riding. A drawback if your ride with a wahoo (like me) is that the data saved in the .fit file relates to muscle oxygenation so you have less ability to dissect the data (i.e. you can compare core and skin temperature), but they mentioned they’ll have a setup soon. And they created a WKO5 sets of graphs to use whether you collect the data with Garmin or Wahoo.


The protocol to determine your “heat training or adaptation” zone is rather simple as explained above. However, I think it may take a couple of tries to get the best possible reading as the first try my heat training zone was lower of the normal body core temperature I normally experience in a regular warm/humid Texas summer day. Once I tweaked the zones slightly It became easier to correlate to various situations.


For instance, the 2nd weekend in June when we had “proper” hot/humid summer weather (low 90s and 65% + humidity), I hit my heat training zone within 20-25 min of riding and climbing above it thereafter by quite a bit. Of course I was hot and my body wasn’t adapted to that heat yet since HR was high ~5-10 bpm at the usual power. And thus, it was a bit tougher than normal ride which may have been easy to prevent where I held back a bit. It also led me to tweak slightly my usual fueling strategy for the usual training weather (mid 80s and humid) for such conditions. ~3 weeks later, almost same conditions (actually a bit hotter), power was normal, HR was closer to normal, and core temp actually stayed within ‘heat training’ zone and the fueling tweaks also made a big difference.


When training in Saint George last week for a week in 95+ F weather (hitting 100F>) and riding climbs like snow canyon, the heat by perceived exertion felt much more intense than normal and yet, my core temperature never hit any higher number than my heat adaptation zone riding at the same power I normally do in TX for such a ride. HR was higher than usual the first few days which I think was more related to the altitude vs the heat. Thus, while St G is was hotter than TX, it was less humid which plays a bigger role in managing body core temp.


As mentioned above, using the core and your heat zone as a guide, I managed to tweak my zones a bit better and have “pushed” the limits a bit to find my “too hot” zone! What I mean is that you can do some training in hot/humid conditions and learn at what temp 10 extra watts may be too much and how far you may be able to push before it significantly impacts your performance. For someone racing the upcoming St G or say Kona, this could be great information to use on race day or simply track your temp live to avoid getting near that danger zone and prevent walking the marathon for instance. (you could do the same for running)


Also, an example of applying it to athletes I coach: reviewing the racing data for Jana (who posted above) post Lubbock 70.3, she didn’t ride/run at her usual potential and the first thing that jumped at me was how high her body core temp (102.2F)was post the swim which was barely swimsuit legal. And though while Lubbock tend to be a rather hot race, that day was unseasonably cooler yet her core temp on the bike stayed above of what she normally would riding at the power. By the run, within a mile the core temperature climb back up even higher that it normally would for that power/pace/HR and weather conditions (102.6F). So we theorized since the swim was barely wetsuit legal and she swimming with one, probably overheated her even though she didn’t feel hot and this perhaps affected the rest of her day. (something to consider next time)


Finally, I do a bunch of testing at my performance lab and I plan to continue doing more testing with the core and I'm thinking of ways to better apply it to my athletes training (like testing body core temp while wearing certain tri suits or cooling devices like the new headbands), use it to tweak fueling strategies in various conditions, fine "too hot danger" zone, etc. But the Core team have been great at answering questions and seem rather open to feedback.


I think it’s a valuable tool for any athlete and could prove useful not only for those training in warm weather or planning to race in hot races. But also, as I used to live in Massachusetts before moving to TX, I see it could be useful for those training up north in the winter/colder months who may have early season races. Thus incorporating some form of “heat” zone training early on may help them perform better. And while those April/May races may not be in very hot conditions, it may certainly be warmer than weather those athletes may have experienced in their training hence allowing them to perform better.


Also, using it could help you streamline your heat adaptation protocols if you live in cooler weather and don’t have access to certain things (i.e. sauna). Using the core you could simulate heat adapting indoors or supplement a session with a hot bath and track your core temp to see if it is in your heat training zone. Finally, you could use it to test gear or help you modify your fueling strategies. i.e. you may drink a bit less in ‘x’ weather and a bit more in ‘y’ weather. And you could test the same with carbs/electrolytes.

If you have any questions, let me know.

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Jorge Martinez
Head Coach - Sports Science
E3 Training Solutions, LLC
@CoachJorgeM

Yup, you can do basic analysis on TP (using a scatter graph) or on WKO5; examples:

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Jorge Martinez
Head Coach - Sports Science
E3 Training Solutions, LLC
@CoachJorgeM

i went to order one, but my debit card blocked the transaction since it was in a different country. gonna call the bank and get that sorted tomorrow.

i feel this will be really beneficial to me. i train half my life in a remote work location. treadmill and bike are both in living quarters where the hvac is kept EXTREMELY cold. i actually started putting a space heater in front of the bike or treadmill to blow directly on me to get heated up. ive known training in such a cold environment wasnt helping me at all. i will love seeing my body temp at work versus the texas heat and humidity and inside at home on the trainer.

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80/20 Endurance Ambassador

Brian (& anyone else who have used this product).

Do you think this device could be helpful in comparing products that have a "perceived" increase in heat / core body temperature?

Off the top of my head I'm thinking back to back outdoor tests where power is maintained between two helmets or suits (with adequate time between runs to allow core body temperature to normalize)... for example, benchmarking an aerohead vs a rudy wing or a black tri suit vs a almost see thorugh white one built to be "lighter and cooler"

What are your thoughts on this??

Cheers
Mike

Yeah, that’s how the Norwegian Triathlon team tested their Tokyo white uniforms. As I mentioned above, that’s how we are planning to test some gear pre Kona. (Ie headband cooling device, kit, etc).

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Jorge Martinez
Head Coach - Sports Science
E3 Training Solutions, LLC
@CoachJorgeM

Answer to 1 - I put the monitor on when I put my hrm strap on which was when I was kitting up to go ride. By the time I let the dog in/out, grabbed my bottles, topped off my bottle from the freezer with water, stuff nutrition into my pockets, rolled bike to carpot, got shoes etc it was usually ~ 20 min. Maybe a bit more sometimes, maybe a bit less others.

Answer to 2. The temps I put in where just place holders for the convo. You need to determine you own inflection point. Your "hey this is where I start to melt down" temp could be a lot lower or higher than "my this is where I start to melt down" temp.

I spend a lot of time riding in at/near/over 100F temps with an 11/11 UV index. Then when monsoon season hits, it's just like being back in Raleigh NC but a bit with typically higher day temps (+2-6F) and slightly lower dep point temps _~2F). It could be 95F and 70% humidity at 10am when I'm rolling back in from my 4+ hour Sunday Funday ride.

(Having spent summers in both Raleigh & Tucson, you guys in the RDU area have it pretty good during the summer comparatively. Summers in Tucson are much harder to train in due to how fast it gets hot, you just don't get that 10-12F rapid temp increase in an hour there that we get here once the sun comes up)

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

Have you experienced any drop out issues with the device? How often does the device need charged? On your garmin, can the ciq data field be added to an existing screen with other native data fields? How noisy or how much variation in the data do you see on your garmin?

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Steve - not to derail, but how much outdoor work do you do/what is your schedule through the summer? I piss and moan about living in Hilton Head, but your situation is much worse but you seem to do pretty well with however you’re breaking things down.

My schedule (as far as indoor/outdoor) stays the same all throughout the year. I ride on the trainer during the week (due to time management and traffic) with the longer weekend ride outside. I run on the treadmill most days during the week and I do my one speed session (typically wednesdays) and long run outside. Any run after my long bike outside is also done outside.

So 1 ride outside a week and 2 runs outside a week on average. But that hasn't been driven by weather necessarily. Mostly by time management and injury prevention (treadmill). If I feel like I need to do a little more heat acclimation, I will take 1 of my easy runs outside instead of the treadmill.

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You're going to need to do several A/B testing sessions imo. Maybe an A/B/B/A then the next session B/A/A/B then do that two or three more sessions. With the crossover you've hopefully eliminated temp increases due to duration as well as ambient temp fluctuation. You'll need to keep the time you're down between runs the same as well. Unfortunately A/B testing is a lot harder to get right than it would seem.

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

In the video they placed several COREs at different positions (forehead, chest, arm, etc.) and talked about coming up with a normalization between them. I'm taking this to mean that you will get different readings from different placements (unlike a optical HRM that should read the same everywhere), so consistency/repeatability in placement is key to get actionable results and historical baselines are needed to know what those reading mean for your performance. Is this correct? Is there some consistent variance vs an established source of truth (ex. pill or rectal)?

Also, how do things like dumping water over yourself at aid stations (and other non-steady-state events) impact the readings?

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ECMGN Therapy Silicon Valley:
Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)

has anyone successfully used this on a Forerunner 920? The device doesn't appear on the 'Connect IQ' list for the Core app, and I really want to use core with this particular watch. (and not have to upgrade to another Garmin!).

Send a request to Core but I thought one of the testers might have dealt with this.

There is a a version for the Forerunner 920 (or Fenix 3, Fenix 2 HR and several other older devices).
It is not available on the store yet but it is a special slimed down version to cope with the memory limitations on the 920.
Working on a new build that will combined the low memory version with the standard version.

If you would like a version of the CORE ConnectIQ DataField for a device that is not listed - just send us a message either here or through the CoreBodyTemp.com website

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CoreBodyTemp.com
info@CoreBodyTemp.com

The tests with Kristian with the multiple CORE devices in Serra Nevada was for some advanced developments taking place. As CORE measures energy transfer it has other possible such as which was also used for Kristian - measure the effectiveness of different triathlon suits with respect to cooling. The CORE sensor play a role in optimizing materials used for his suit used in Tokyo.

As for dumping water on your head at the aid stations - it more effects your core temperature than the CORE sensor.
Recommended to dump water on your head at aid stations and also good to start early. It is better to slow getting hot than get hot and try to get ride of the heat. Similar to dehydration or fueling - better to do preventive than fix it when it is too late.

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CoreBodyTemp.com
info@CoreBodyTemp.com

There are a few ways to use CORE to test clothing / helmets for effectiveness with cooling. Often we will do these tests along with Areo tests at the same time so to weigh the trade off's between areo vs cooling or better to optimize the combination of the two.

If you would like more information or better suggestions on some ways to test please feel free to contact us at corebodytemp.com

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CoreBodyTemp.com
info@CoreBodyTemp.com

There are a few ways to use CORE to test clothing / helmets for effectiveness with cooling. Often we will do these tests along with Areo tests at the same time so to weigh the trade off's between areo vs cooling or better to optimize the combination of the two.
If you would like more information or better suggestions on some ways to test please feel free to contact us at corebodytemp.com

Some products definitely have a greater influence on increase core body temperature but the perceived differences can be misleading. The perceived value of core temperature does not always match what is happening. I have been almost shaking riding down Swiss mountian passes in the rain and thought I was cold - but my core temp was still fine (verified with e-pill) but my body's defense could see I was loosing a lot of temperature through energy transfer so was trying to tell me to do something about it. The same can go with heat - perceiving early on this is hot or slowly getting core temperature very high and not feeling that hot.
An quick example - we all know what temperature is but if I ask you to hold your hand out and tell me the surrounding air temperature within a degree or two, very difficult (as humans we are bad thermometers but our perception is not so much temperature but energy transfer).

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CoreBodyTemp.com
info@CoreBodyTemp.com

Heat training / heat acclimation is one area where 'more' is worse or even dangerous.
Most the research shows for heat training you just need to be in your 'zone' - going much above this adds not additional benefits but can cause too much stress. Overdoing heat often shows up a few days later and serious heat illness can take a long time to full recover (get back to your old form/pace)

So if doing heat training - best to monitor core temperature and heart rate.

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CoreBodyTemp.com
info@CoreBodyTemp.com

CORE worn the chest will be more accurate. The arm can be used but with less accuracy. The arm is often used for 'work place safety' as it is more convenient to be worn on the arm (can even be worn over a thin shirt if worn tight). Though for sports, worn on the chest and paired with a heart rate monitor is the recommended more accurate position to wear a CORE device.

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CoreBodyTemp.com
info@CoreBodyTemp.com

There are no consumables for normal sports wear when worn on the heart rate monitor on the chest.

The medical grade patches are more used when monitoring 24/7 but one can generally be used for multiple days. My wife often clips hers onto her bra instead of using the patches.

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CoreBodyTemp.com
info@CoreBodyTemp.com

Thanks! This is helpful. Tho going back to a chest strap isn’t enticing.

Spending my summer try to figure out how not to blow up in Hawaii this year.... not to derail this thread (and I do think based on this thread I will buy the CORE even though still not sure how I will implement into racing) but any gear or kits yall have found to be preforming better in heat? Anyone know what brand of kit the Norwegians used?

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2024: Bevoman, Galveston, Alcatraz, Marble Falls, Santa Cruz

Another tester here!

Like most everyone else, I found these very easy to use and to incorporate into training and have enjoyed the extra metric. Most of my training is running with a couple of bike sessions sprinkled in during the week. My approach to using CORE has been for heat adaptation. Living in Maine, I get about 3 months of "hot" running per year, which doesn't allow for a lot of heat training, particularly for early season races.

The first session I did with the CORE was an easy long run on a fairly humid and hot afternoon. My big take away from that run was how quickly my body temp went up to 100.4 (the number we look to hit to start the heat ramp test), then leveled out briefly before slowly climbing to just over 101, but I never felt like I was overheating. After the run I kept the monitor attached and like most of the other, was amazed at how long my temp remained high, despite it not feeling like it. The following day I performed the ramp test on the bike. I layered up in tights, long sleeve shirt, jacket, gloves, and hat and hit the trainer. This time around I was surprised at how LONG it took to reach 100.4 despite feeling over heated far before that. I was able to maintain HR and power longer than I thought I would but eventually it started to fall off, while body temp never rose above 100.5. Now that I had my optimal heat training zone, it was fun to see where I ended up on harder training runs (I run far more than I bike these days). I rarely exceed the training zone but the big take away for me was how what I'm feeling and what is really happening, can be VERY different. There were days where I felt absolutely cooked but my temp said otherwise. And days where I felt ok but backed off as my body temp was climbing too high. I'm looking forward to continuing this in the winter, when everything moves indoors and I hit the bike a bit more. It will be great to hit some longer training blocks mixing in very specific heat training and see how I come out of it next summer.

I bought one and it arrived today.

I guess I should have checked to see if it were compatible with my Coros Pace watch...

Now I don't know what to do with it. Silly me.

Mine came in today and used it on a trainer ride. A few comments/questions:

- can skin temp be added as a iq data field for Garmin? I’d like to see both core temp and skin temp on my Garmin.
- can the battery level % be added to the main screen on the app (at the top)? It took me forever to find the battery % on the app.
- consider turning on the existing light to a certain color to indicate the device is charging and when it’s 100% charged.

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Not sure what I can disclose publicly but... I can say that COROS is aware of CORE and how to support it in their products. So the problem you have should be resolved in the near future.

If you let COROS know that you also would like their devices to support CORE - it can help in accelerating the process.

But we don't want you to have something you feel you can not use - please send me a message and we can help sort a solution for you.

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CoreBodyTemp.com
info@CoreBodyTemp.com

only used the core today for an easy trainer ride. i can already tell this thing is gonna be a really cool gadget.

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80/20 Endurance Ambassador

So I have had mine for all of four days now…

I am curious what others have seen for peak temperatures. I did a hot Olympic triathlon today and saw 102.1°. It was not the most miserable I have felt, but it was hard.

Wow. Thanks so much. I appreciate the feedback and follow up. I followed your recommendation and have emailed them. Fingers cross something happens soon. In the meantime I have dug out my old Garmin bike computer and set it up so I will have it on the bike, and I might just carry it with me on the runs for a bit.

Plus I was thinking I can train inside over the winter on the treadmill and trainer and see it with my phone. So a premature reaction on my part. As someone who struggles mightily with the heat, I'm very interested in using the CORE. Thanks again for the followup!

Reminder that temperatures are very individual so what is hot for one person can be different for another (similar to heart rate but maybe even more individualistic)
So 102 for one could be easy where another could already be in the 'limit' zone.

Though 102 F is fairly common for a well trained athlete whom has been training at elevated temperatures but at 102 most would need to be adopting a slightly slower pace (power loss due to blood being used for cooling vs fueling).
But at the same time we have seen people over 106!

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CoreBodyTemp.com
info@CoreBodyTemp.com

two trainer rides… first was easy 45 min with no fan, i hit 102.7. next day was an hour with two 10 min intervals right below ftp and wahoo fan on full blast the whole time, 102.9.

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80/20 Endurance Ambassador

This is interesting. I’ve had mine since Thursday and attempted the prescribed ramp test on the trainer and barely made it to 100.4 @80% ftp (~260w) after 15 minutes there. I have however noticed that every time I start out I’m below 98 degrees and right around 100.0 I’m absolutely pouring sweat. Yesterday on a 10 mile run with some efforts in 90 def heat and 70% humidity I just barely cracked 101.0 but I was definitely in the zone close to where I couldn’t have done another couple of miles.

I wonder if you’ve been able to see any correlation with heart rates and body temp? I typically have HR’s when sitting down in the 30s and I can count on one hand the # of times I’ve seen above 160 in the last decade. It’s interesting to me that I’m low compared to others in regard to both.

i start out around typical body temp, 98.3 for the first ride and 99 for the 2nd. i’m guessing ambient temp was around 80.

hr climbed quickly and was higher overall with no fan, with fan it climbed lower and sustained lower.

this is just two rides though, need much more time using the product before i feel there’s any quantifiable data to use. that said, those two runs told me to never try and ride without a fan.

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80/20 Endurance Ambassador

On my long run yesterday, I saw 103.

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logged into the app today and it forced me to register an account and now i can’t swap the temp display to F.

booooooooo.

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80/20 Endurance Ambassador

It should fix itself next time you open - it did that to me yesterday and when I opened this morning it was in Fahrenheit

thanks for the feedback - just logged that as an issue.
The accounts are needed for the next version of a much improved in the works at the moment. The accounts are more for personal data security (some uses cases people don't want others to see their 'medical' information) and remote monitoring.

But thanks for the feedback will make sure it gets fixed

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CoreBodyTemp.com
info@CoreBodyTemp.com

the F issue did fix itself. phew!!!

my suggestion is to have the ability to opt out of signing into the app. every piece of tech i have wants me to have an account, log in, give all this info and as an end user i just want my device to work with my preferred service (garmin connect —> training peaks).

also today on an outdoor run the unit measured me at 108 degrees for the entirety of my run. same chest strap used and same body placement as before.

was there some firmware pushed out over the past couple of days?

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80/20 Endurance Ambassador

I’ve used on every workout for the last several weeks. As noted above in the thread, I’m on the high end for sweat/water loss - but I guess I never really expected I’d be pouring sweat like I am when my body temp only increases 1 degree F. I’m starting to play with increasing fluid consumption on all workouts to offset, and while I’d previously stock cold beverages every 4 miles on a long run route, I’ve moved that to 2 miles.

What’s been interesting to observe with this is feeling hot and actually being hot - they are not always one and the same.

just wanted to post up some customer service feedback. i had issues with my unit. sent some info in to the core rep here and they immediately dispatched me a new unit when they saw mine was having problems. great customer service.

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80/20 Endurance Ambassador

and unfortunately my 2nd unit is essentially DOA. ive tried all the typical troubleshooting i can actually do, delete / reinstall the app but i cant get this one working. im hoping im just unlucky because as it stands ive gotten two defective units.

also unfortunately our local core rep is failing to reply to emails or PMs asking for assistance. hopefully he's just busy, but previous communication was pretty quick.

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80/20 Endurance Ambassador

Apologize Damon - please check your inbox(es) - yes typically we try to respond quickly but busy is not an excuse so this one is on me for not getting back to you sooner. Will try to get your issue sorted asap.
Thanks

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CoreBodyTemp.com
info@CoreBodyTemp.com

Interesting interview with Kristian Blummenfelt (and Hayden) speaking on their technological preparation for Tokyo and their use of CORE (@ ~18 minutes)


The Physical Performance Show with Brad Beer
286: Featured Performer: Tokyo Men's Triathlon Podium Recap: Kristian Blummenfelt (Olympic Champion) & Hayden Wilde (Bronze Medallist)

Full link:
https://podcasts.google.com/...PyAhUAAAAAHQAAAAAQAQ

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CoreBodyTemp.com
info@CoreBodyTemp.com

Anyone here use a core and a stryd both paired to a garmin watch? I'm starting to see power drops with my stryd and stryd is thinking there may be a conflict with the core device and multiple ant+ devices. I need to run a few tests but I figured I would ask if anyone has had similar issues. We confirmed the stryd itself is reading correctly and the issue is specifically garmin dropping the stryd signal.

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I have both paired to a fenix 6 and haven’t had any repeated dropouts throughout workouts that I’m aware of. I do however have what appears to be a reconnecting/re-pairing that happens almost 2 minutes into every run with all connected devices (HRM, stryd, core, and headphones). It fixes itself though and when I review data after I don’t see evidence of a prolonged dropout. My newest device added was a polar h10 so I tried to troubleshoot through polar and they don’t think it’s theirs that’s causing the issue.

My thought is it’s likely a garmin problem, not specifically core/stryd/polar/etc. I stopped troubleshooting since it wasn’t ongoing throughout a workout

Thank you. Yeah my issues are more disconnects/re-connects than drops. I've mainly been running on the treadmill and would see 1 or 2 disconnects per run. But then on sunday I ran outside for the first time in a while and the disconnects/re-connects were very frequent. Ran again on the treadmill yesterday and didn't notice any disconnects. You may be right that this is a garmin problem.

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I can provide the opposite datapoint for ballast. I have a 945 connected to a Stryd, Core, and Rhythm+ 2.0 HRM. I do not get any dropouts with the Stryd or Core. I do get occasional HRM dropouts (like 2-3 long run), but I blame the Rhythm+ for that.

Hi.

Is there any independent testing validating the measurements?

My reason for asking is that I have a friend who does science where temperature measurements are needed. He have tried Core for a while and gave me plenty of charts where the correlation between Core and a temperature pill was way off. I would really really love for it to work, but I need to know that the numbers I get are fairly legit.

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http://www.triallan.com
Ambassador of:
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Precision Fuel & Hydration

I too have the sensor and am trying to find its place in my training. I would be interested in your critique of this article I came across.

Thanks

https://human-performance.si/...-temperature-sensor/

They just had a big firmware update. Before the firmware update I was getting some unrealistically high temp readings - 105 degrees F on pretty easy workouts. Updated CORE yesterday and temps seemed much more realistic on a hard trainer ride this morning. Maybe give the update a go and see what happens.

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Blog: http://262toboylstonstreet.blogspot.com/
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Hmm. The specific issue I’m having is on a 945.

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I was initially having a major PITA problem with my 945 and the 2 CIQ fields, because somehow the watch thought I had more than 2 fields in use. I could set it up, and it would work for a run, then it would lose my Core field the next workout. To fix it, I removed both CIQ fields, rebooted the watch, added them both back, and it has been fine since.

Edit: I remembered one more thing that is a little different for both of these devices. Both the Stryd and Core mobile apps have an input field where you enter the device's ANT+ ID. I never paired my Core to the 945 - I just entered its ANT+ in the phone UI. For the Stryd, I did pair it and I also added its ANT+ ID through the app. Maybe this is related - how did you connect & pair your devices to the watch?

Hi, everybody:

Let me respond to some of the latest questions on this thread.

With regard to the connection issues - in our experience, sensor dropouts tend to be together and is a general signal issue which is not CORE specific and can be an interruption from another source (we have spotted some interruption for TV cameras with all the broadcast equipment). Of course if you are spotted dropouts in just the CORE signal, while this is not an issue we have spotted a lot, you can connect with us and we will help trouble-shoot.
We have just released an update so recommend this as we have both updates and fixes.

For the question on comparison data, one important detail to keep in mind is that the CORE sensor works in a different way to conventional thermometers and it is validate it for specific activities. Our primary reference (for our testing and data collection) is e-pill data. E-pills have the advantage that they are more convenient to use broadly for sports (i.e. as outdoor as well) and there is better acceptance by athletes compared to rectal thermometers.
We document and communicate that there are use-case scenarios for sports in which our accuracy is lower. For activities such as sauna use and indoor high intensity interval training we have room for improvement. The advantage is that as we continue to collect test data and 'train the algorithm', algorithm updates can then be pushed out to everyone using the CORE sensor.
A reassurance for athletes is that the measurements data is reliable and repeatable - so for athletes training in activities in the edge cases - the measurement data still provides an individual and appropriate baseline. Keep in mind that thermoregulation is individual so your training and thresholds should be based upon your own data.
With regard to validation of the CORE sensor, we have interest within and beyond sports for our technology and are currently undertaking a number pilot studies. For example with Ice-Swimming, the thermoregulatory response of the body is quite different to warm water swimming so this requires continuing data collection on our side to better understand behaviour, to train the algorithm and to validate.
When looking at comparison data from other sources, we are always interested to know whether the activity is validated or if it is an activity where we have documented limitations in the accuracy. It is also important to understand how the tests are conducted and we are proactive when athletes, coaches and scientists are testing to ensure they have the relevant information and support.

We are aware of a study recently published which tested the CORE sensor and earlier this month submitted a rebuttal to the Editorial Board. This week received the confirmation that this it is now being reviewed to address a number of issues we raised. At this stage we need to await a response and outcome.

For anything else, feel free to send me a message at any time.

Cheers,

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CoreBodyTemp.com
info@CoreBodyTemp.com

Thanks for all the answers on this thread. I just got mine this week and did the ramp test, have lots of questions, hope you can answer.
1. The ramp test determines the "heat training zone" - should these temperatures be also used for running heat adaptation sessions? I'm assuming so, but HR for example is different depending on sport
2. Can the garmin field be set to different F/C configuration than the setup of the device?
3. Why is the garmin field blinking?
4. In the alert setup of the garmin field, what number to input? is it the temperature for the alert? If so, is it in F or C (or whatever the watch is set to)?
5. If I wear it all day with the sticker - will it stay on the body during swimming (is the sticker strong enough and water resistant)?

thank you

Hi DoronG,

Thanks for the questions - I'll try to address them below:

1. The ramp test determines the "heat training zone" - should these temperatures be also used for running heat adaptation sessions? I'm assuming so, but HR for example is different depending on sport
>> same temperatures ranges can be used which are 'fairly' independent of heart rate

2. Can the garmin field be set to different F/C configuration than the setup of the device?
>> On Garmin devices - it uses the temp settings of the Garmin device (C or F) - so a watch could be different from a bike computer working with the same core device.

3. Why is the garmin field blinking?
>> is this when a few digits go missing at the end ? such as 103.- >> 103.1 - this shows that the signal quality/value we are showing might have some accuracy issues. So when you first put it on we display a value but the level of confidence for accuracy goes up after 10 minutes so the first reading could be off a little. So if you first put it on and checking for fever - we would say leave it on a few more minutes... But true we should explain this a little clearer and will do that. Thanks for reminding us.

4. In the alert setup of the garmin field, what number to input? is it the temperature for the alert? If so, is it in F or C (or whatever the watch is set to)?
>> if using a alert temperature - it uses the settings of the watch. If your watch displays temp in C, the alert is in C - visa-versa for F

5. If I wear it all day with the sticker - will it stay on the body during swimming (is the sticker strong enough and water resistant)?
>> for swimming - better if you can use a chest strap. I have used the stickers in the water but... no guarantee and think if you were swimming faster could likely loose adhesion


Hope that answers most your questions - please keep them coming. You can also find more information on our website and FAQ pages


Thanks,
theCOREguy

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CoreBodyTemp.com
info@CoreBodyTemp.com

Thanks very much for the answers
I will post some feedback here after using for a while and doing some heat acclimation training

Look forward to hearing your results - again please let us know if we can assist in anyway.

We like to clarify the difference between 'heat acclimation' and 'heat training'.
Where 'heat training' should provide benifit in all conditions - when you compete you will have a higher core temperature do to the power you are producing. Heat training is to help put your body in that type of stress so it can become more efficient.
Heat acclimation is very similar training - but usually done a few weeks prior to the competition so your are prepare to compete in those conditions. Most try to simulate similar conditions they will compete in and we have some now applying this same concept when going from warmer climates to cooler climates...

Thanks again for the questions - and looking forward to hearing how you go,
theCOREguy

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CoreBodyTemp.com
info@CoreBodyTemp.com

We have some news that may be of interest for the community, a small team from CORE will be on-location at the 2022 Kona IRONMAN so this will be a chance to connect with directly. We are also joined by Moxy and VO2 Master as Data Powered Performance and would be thrilled if you drop by and say you are from the Slowtwitch community.

Look out for us in front of Huggo's on the Rocks from Sunday through to Saturday... we have a few real highlights.
And if you are competing, good luck!

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CoreBodyTemp.com
info@CoreBodyTemp.com