That's just my point. Airflow doesn't make as much of a difference in humid conditions, because evaporative cooling is minimal. You're going to be hot whether you mantis or not.




Totally disagree. The trade-off between temperature and power output is curvi-linear starting at fairly low temps, it does not just start at some really high threshold:

https://www.physiology.org/...plphysiol.00367.2010



When you're generating 250-300 watts, you're generating more heat than a hair dryer on full blast and it's easy to push high core temperatures even when the ambient temperatures are fairly low. Check out XC ski racers, who wear practically nothing when it's 15 degrees.

I can tell you from lots of experience, airflow has a major impact on both cooling and power output even at fairly low temperatures (50-60 deg.). Anybody who has been on an indoor trainer both with and without a fan can tell you that. Turn on a big fan and voila! you have an extra 10 watts.

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My latest book: "Out of the Melting Pot, Into the Fire" is on sale on Amazon and at other online and local booksellers

Hello jens and All,

Another cooling reference:

https://groups.google.com/...lHCTrFQ/zdGJFdBv1Q8J

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Cheers, Neal

+1 mph Faster

Hello Shambolic and All,

If your theory is valid ..... looks like what is needed to relax the upper body is a seat belt or better yet ..... a clip in butt rig. Sit and you click into to the seat. Twerk and you are released.

Legs do the work and upper body relaxed.

In the olden days of triathlon some riders experimented with a cable attached 'bike to body' to generate more power .... I have seen pics of the rig here on ST.

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Cheers, Neal

+1 mph Faster

Heat kills me. I got heatstroke a couple decades ago in a race >100F and I've had low tolerance since. I wouldn't even think of riding hard on a trainer without a couple fans. And when I used to put my trainer on the deck at 30F I needed a fan then too (bad idea, but that's another story). But I figured I was an outlier. If modest temperatures are enough to slow you down, why do people going for hour records want temperatures 80-85F?

I know airflow, temperature, and humidity matter. But in this case you are postulating that the mantis position blocks airflow enough to inhibit cooling and degrade your power production, even with modest (70F or less?) temperatures. Do you observe a drop off in power with temperature when you do intervals outside? I can do as well at 85F as 50F (not humid), for TT intervals up to 15min anyway. That should be long enough to see something.

It will be interesting to see what you come up with.

Ceteris paribus, at record-level speeds (50kph), going from 60 degrees to 85 degrees equates to 17 watts less air resistance.



IME, the heat effect doesn't really start to kick in until after about 20 minutes. I actually have a fairly large dataset of 30-40-minute intervals from 50-75 degrees conducted both with and without fans. The HR is virtually identical in most of them for the first 15 minutes or so. It varies a lot after that, depending on the temperature and fan/no fan.

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My latest book: "Out of the Melting Pot, Into the Fire" is on sale on Amazon and at other online and local booksellers

It's 4.8% anyway, and lower air density means lower power output as well. I was thinking about Aguascalientes where everyone wanted to wait for it to get >80F. You are already at 6,000ft so the drag gains from further lowering air density are nearly balanced by the power reduction. If it's hot enough to reduce power in addition, it doesn't seem like optimal conditions.

HR/watts does climb when it's hot, but HR is a poor proxy for pretty much anything we care about. The question is, is it hot enough to inhibit your power output, and how much?

According to the link you posted above, it looks like 15min is long enough to see a big difference if it's hot (40C or 104F), even though core temperature was the same in both cases: "Ely et al. (22) examined 15-min cycling TT performance in two environments (20 and 40°C), which produced Tsk of 31 and 36°C, similar to MacDougal et al. (58), while Tc remained near 38°C. Ely et al. (22) found that ratings of perceived exertion (RPE), heart rate (HR), and Tc were similar between self-paced trials. Total work performed at 40°C was 15–20% less than 20°C (with test CV ∼5%)"

This is the reason we can't have nice things.

Hello

what Antony Costes says is true, of course, it is physics law. But it does work differently for different peoples.

I made some experiments yesterday. Took my road bike to some D+ and tested different things.

1) vertical balance (you push on pedal, does your butt leave the saddle ?) : even at 400w, RPM 100, butt not leaving the saddle, without help of a belt, or grabbing the bar

2) lateral balance (you push on right pedal, do you fall on the left side of the bike ?): more tricky
I tested up to 250w (more than I apply in a 70.3), RPM 75. I tested how I grab the bar. Well... finished with only one finger on each side, with no pressure on it. And my torso do not seems moving.
I don't need any help of hand/arm to stay stable on the bike pushing the pedals. So I searched how this was working, at least for me.
Answer is : when pushing on right pedal, the bike slightly angle to the left, then pushing left pedal, bike slightly angle to the right.
My core absorb this small left / right movement of the bike, while my torso do not move, and shoulders, arms and hands are totally relaxed.

I suppose others peoples might have different strategies to keep their balance (consciously or not). Including using their hands/arms/shoulders.

For me it probably came from track work, at 120+ RPM, trying to keep hand and arm relaxed, mandatory in tight peloton races.

I agree it works for different people and especially different distances. So as you say at 250W which I come close to averaging on a good IM you were using relatively little support. I generally average low 80 cadence now and in the only IM I did more mantis my power was initially fine but tapered away with fatigue holding stability as you can do but relying on core, not having as strong foundation as I can create up front. I have said all along I feel I can generate the power but it doesn't feel as easily generated and my max power is lower. Why purely rely on core to stop bobbing about when having a more solid front end you can have to rely on it less with a more tenses hands/arms locking your shoulders. I'm not tearing my bars off but have some tension. I understand all this and as I have said I found a way to overcome what I found a more relaxed front as my arms went up and could keep the ability for me to maintain power. I was trying to share my findings with the OP and GreenPlease who said they lost power going mantis to have rruff who just has followed me across three treads now to say I didn't lose power, Antony Coates is full of shit as well, I'm right, your wrong but I have nothing to add...

If you look at the example pictures I sent from the Olympics the rider who won gold Cancellara was in a pure power position if you want to trial that with hands lower than elbows and pads forward of elbows and tell me differences in max power you can produce as compared to what you can in mantis I would be interested in. I have done this. This is all trickle down when it comes to riding efficiency. Maybe I have an inefficient pedal stroke and rely on having tension through my front end, maybe it's I have a weak core but rruff says core has no impact I find that very funny. Especially because it come out now he does short racing like 40km and I'm talking about Ironmans. I don't know but as Antony said generally you need to apply more force than your body can provide and maybe in the short time you tested you could do it with core? I would be interested in what Antony has to say but after the antics that have gone on in this thread he would be unlikely to respond. He actually used to ride a very powerful position before going up. Hence I would be interested in his input.
http://antony-costes.onlinetri.com/index.php?page_id=8232&news_id=54547

This has all become a side track and people trying to discredit what I was initially asking by sharing what I could see what may the true answer from my findings.

If going mantis is more aero then why aren't the top uber cyclists in IRONMAN doing it more so?

I have had one poster say as yaw angles increase then it isn't as aero but the trend had been that going mantis is more aero and with the relaxed position guidelines for tt racing in the UK they are all going very mantis and even the UCI cyclists are starting to go that way. I actually find it a more comfortable position that has won me over more than anything.

Maybe it is relying less on core for the bike and that helps keeping it fresh for a run off the bike (definitely not Starky) I don't know there may be other reasons but no one seems to actually want to approach. Starykowicz, Kienle, Frodeno, Weiss who was actually flatter (less mantis) than years before at Kona and rode second fasted bike and I think highest average power NP 334W, why aren't they going more mantis?

I know very basic summary this article sums it up. It says mantis relaxes your arms as I've stated and is it because biomechanically they lose the ability to generate power over an Ironman and those loses are greater than the aero gains?

https://triathlonworld.com/gear/hit-your-best-triathlon-bike-split-nailing-your-suit-helmet-wheels-and-position-144987

Aerodynamics is not a single step, but a process. It is no coincidence that professional athletes invest several hours in aerodynamic measurements to optimize their position and equipment. Here’s a summary of our findings from our MAD Days tests:

1. Postion is where you need to start. Athletes achieve their greatest success through a biomechanically optimized position combined with an aerodynamic position. Those should be taken care of with a professional bike fitting.

As you say, many different questions

Mantis more aero ?
it seems that high mantis give very good results in some cases, but of course it depend on many parameters. Possibly in some cases you don't need to go that high to reach your peak aero.

Mantis vs power ?
probably each rider have its own way of pushing on the pedals, using muscle chain differently (or different muscle chains) to stay stable, and this is changing with fatigue. If going to use the arms when core fatiguing (apparently your case), certainly the way to put the arms have an impact.
If I remember well Tony Martin went to low mantis at some point (from flat) then went back a bit. He saw the aero advantage, but this was probably too much a change for his muscle chain ?

Why uberbiker not going higher mantis ?
it is a risk to change position, and adaptation of muscle chain take time. When you are already very good at this game, it is probably difficult to invest a few months of adaptation for an insecure result. Probably more difficult for an "old" uberbiker to adapt, than new comers. Look at Lucy Charles position for 2018m compared to 2017. Probably aero optimized, and she can adapt more easily, as she is new to the game. Muscular chains still to be fully develop. I suspect CdA around 0.185, and less than 200w average in Kona for her.

I agree and good input. The kind of conversation I was hoping for not 'you don't lose power.' I do think power and cadence fall into that fact and why you will see uber biker Ryf in classic power and a more slight Charles with less power probably higher cadence going more mantis aero maybe compare to a Lange. As I say look at Weiss position on the same bike at Kona over the last few years and he has actually gone flatter this year. It is a trade off for riding style, power and aero gains and he is a power rider. Aero are proven easy gains but if you lose power then you will be reluctant to go there. The more uber bikers seem more concerned about getting aero gain through going narrow over raised hands that is probably more biomechanically optimized for them staying flatter? As you say there are so many variables in play and every athlete is different. I just wanted to have a reasonable discussion like we are now.

250w=184.4 ft-lbf/sec
80rpm=4.4 ft/sec assuming 160mm cranks

so ~42 lbf at pedal for entire revolution if you assume you only apply force for 50% of revolution, then ~84 lbf during power application. you are going to have to be pretty small to lift yourself off saddle or put out mega watts(as rruff says) . I used to do 500w+ for 1 min in aero with no tension in arms. the folks I know that pull on extensions do so cuz its just how they learned to ride(and tend to be more squirrelly, in general) and any force generated pulling up is lost at armrests. if you use you core and pull up on bars on a road bike, you can pop a wheelie

Everyone keeps saying this so tell me why Cancellara in the position I showed at the olympics is reefing on the bars at say 400W in a less aero position? Antony Coates said you need to put force on the bars, I'm saying I need to put force on the bars. I need to create a solid foundation to not rely on my core in an Ironman. You must have an extreme core to not put force on the bars at 500W and it isn't sustainable. I'm talking 4-5 hours efficiency. It is about creating a solid shape using more major muscles to save your core and enable more efficient power transfer.

Once again as you seem to be an 'expert' then answer my question rather than attack what I have personally found and explained.

If going mantis is more aero then why aren't the top uber cyclists in IRONMAN doing it more so?

it's not more aero for me, maybe it isn't for them

I did not attack in anyway, just pointing out science



experiment.....get on trainer, ride at 250w in bars, now sit up riding no hands and notice power does not drop, rest is supliferous(sp), doesn't mean you don't prefer your method(damn double negative, you get the point)

or...….one could ride a road bike like that horrible example of a cyclist in the chevy or gmc truck commercial(makes me want to barf) :)


edit: and I don't know how those folks in the tdf can ride the invisible aerobars, but they do as do others on this board

I get the point but as Antony Coates who has done a study on it that the amount of force you exert on the pedals is more that just sitting on the seat supplies and you need to pull on the bars, a perfect pedal stroke (that very few people would have) or accelerate the trunk. You can rely on your core but I find it more efficient not to.

my core is crap, as every PT I have ever been to has told me.

I tried riding down the road once pulling on the bars some, that was not entertaining. I prefer to put my energy into my legs and not waste in my arms, in my case. my bars have no tape on extensions, hands get sweaty,I usually just hook one finger under the edge of the shifters unless its a rough road, then 2 or 3. my pinky finger is not going to support a whole lot of load. I also suffer from carpal tunnel in both hands, so cannot, even if I wanted to, grip the bars with any force for long(also why I XC skate ski sans poles) your abs and lower back will support a lot of load and do whether you are trying to do something or not.

sitting upright on a chair, I just applied some single foot force to a scale knee bent at 90deg with hands crossed on chest, less than ideal, result....52 lbs( I am weakened from open heart surgery so have pity on me, plus my legs are killing from second day of trying to jog on treadmill(reminds me of why I don't run much, ugh))

end result...ride how you want as it works for you. just supplying my anecdotes here

Are you posting here under both the names Shambolic and Hambini?

Haha no haven't seen any Hambini posts?

I did some hard intervals on the trainer the other day, and at 500W my butt stays put with no input from my arms. My core isn't doing much either. Is core fatigue really a thing? I've experienced fatigue of my pedaling muscles (legs and glutes), which leads to a break down of form (more moving around)... I guess so I can engage the muscles a little differently so I can get more out of them. But my core isn't working hard as long as I'm in the saddle.

Curious, did you lose power in mantis? A lot of people here claim they do.

https://www.cyclingweekly.com/fitness/training/strong-to-the-core-31235


https://tridot.com/why-core-strength-is-so-important-for-triathlon

Yes, I know plenty of people tout the importance of core strength in cycling. It's quite the fad. It isn't true though unless you're a track sprinter.

If you are bracing with your back, stomach tense, or pushing or pulling on the bars to ride at 250W, I know you are applying forces that are *unnecessary*. I know because I don't do it, and most *good* riders don't either. And pretty simple physics will show you that it's unnecessary as well.

But that doesn't mean you *can't* apply unnecessary forces. Since it doesn't directly effect the muscles you are using to turn the cranks, it may not even slow you down. So knock yourself out, rowing on those bars. On the other hand if you'd like to learn how to pedal without unnecessary tension, that could be an interesting discussion.

my mantis wasn't that extreme, 15deg plus "tall" extensions, but at anything above 10cm above armrest for extension end, CdA goes up for me.

I did not note any power loss 0-15deg, but then I made sure I kept elbow drop the same. My guess is that not all folks make sure they keep it apples to apples and end up with more drop as they go more mantis and don't take it into account.(it can be substantial) since I keep my elbows on armrest, it is easy for me to know how much to adjust drop to stay the same.

I'd also need more reach to go more mantis as my helmet touches my arms at 15 deg with my head tuck

I do(well, did) seated 700-800w uphill repeats(short duration) seated, no arm tension butt did not go anywhere, rpms for that are 115-125

Hello

well... no, you are totally wrong.

some peoples here concentrate on the VERTICAL aspect : "when I push on my pedal, will my butt quit the saddle ?". This is NOT the problem. In tri the pedal push is too light. And in sprint, you pull nearly as much on opposite pedal. So, not a problem.

The real point is LATERAL ROTATION : I push on right pedal, and (sometimes) pull on left pedal. Logically, my butt should rotate left massively. So, what prevent my butt / hip to rotate left ?
The.... what ?.... the.... CORE

The CORE muscles prevent the hips to go left and right, curving your spine alternatively on both sides. They ensure the link between the hips and the torso, making possible to stabilize the hips LATERALLY using torso weight (in my case, mainly through slight bike angulation, in some other cases through elbow on the pads, or arms and hands).

When Shambolic express he need a "strong foundation", probably it is not core weakness, but simply lack of equilibrium. His core is not weak, simply it doesn't succeed in counteracting pedaling effect (lateral rotation, NOT vertical take off) with torso weight, so it use arms/hands. But the stabilizing force is still transmitted via core.

And for you, you use your core muscles. Even if you don't know it. If you pedal soft, you use them soft.If you pedal hard, you use them hard. Without the core muscles (essentially lateral one, not abdo), your hips will be wobbling around, and your spine will hurt.

Yes core is quite a fad you really are an expert it seems and I'm sure all top sport athletes including triathletes will agree. Despite all articles, Antony Coates input who studied it and everything else you keep believing that...

'Core strength will allow you to handle the output generated by your legs so you can stay in the proper triathlon bike position for the entirety of the race. You’ll protect your back muscles, you’ll increase your oxygen intake, and you’ll stay efficient longer.'