GIGO

I have been using a Stryd for a couple years, and I really like it. I have not gone full-in by training to power like on a bike. But, it has the same potential. I know my critical power from some all-in 5K races. And I have run other longer races to a target power with excellent results.

Have you got some sample training plans / workouts you do?
How does it look to run with watts? Do you have like an FTP in cycling and train based off that?

It is not to generate problems.
Only my opinion.
I am a person like many who puts many hours into training.
I have stryd since it came out in its first version.
The one that was chest strap.
The truth is if you are in a place where you do not have wind, the environment is controlled, you could get to work by power.
Outdoors, I think not.
It is a personal opinion.
Does not take into account the wind
There are studies that say that does not affect, but good each one draw their own conclusions, a pass of 1000 against wind and in favor and tell me if it does not affect;) jjejejej
I use it to measure the rhythm that is more even than the gps, and as a metric, stop using the other functions.
I hope not to generate a problem is just my opinion

Sorry my english
Rafael

I'm a subscriber to TrainerRoad and I've been using mine with their workouts. If I'm at a treadmill I'll even change my FTP to my running Stryd FTP and track my power with the app

I started running with Stryd about 8 months ago, and I credit it with the gains I have made in my running. Running is my weakest discipline, I'm fairly slow, but I would always go out too fast for me, and by the time my HR caught up I was gassed. Plus, my HR can be kind of wonky, so trying to train by that, and with the variability of weather conditions thrown in, I wasn't really improving via HR training.

Having the power numbers in real time has taught me a ton about what an easy run is, what a tempo actually is for me, and most importantly to the terrain I train on, how to not blow up on hills and stay steady. For me, I test with my coach about every 6 or so weeks, and I get power zones to work in. So he'll give me what zone to do each run in, and each zone has a range of about 25 watts to work in.

I am really happy I got it.

It's a neat little gimmick.

Most people who race on the road only care about one thing: their finish time. If I need to run 2:59:59 to qualify for Boston, then I need to run 6:52 miles for 26.2 miles. Boston doesn't care if I averaged 300W for 3:02.

Also- the Vaporfly was tested to be 4% lower than average trainers at around a 6:00 pace. Trainers with TPU based midsoles (like boost) are going to be less than 4%. That's why world records aren't 4% lower all of the sudden.

I also agree with you assessment that it has little use for road running for the same reasons. Perceived effort and the course is often more important than any wattage number. I like to use the Boston Marathon as my example. The first couple of miles have a large downhill. Running goal pace (say 6:00, which on flat ground is say 300W) means that you'd actually be using less energy (wattage) on the downhill. If you ran your goal pace wattage (300W) on that downhill, you might be running 5:20 pace, which in turn would damage your quads and kill your race the 2nd half.

Cycling power makes sense as you're locked in to your pedals - each rotation is the same whether you're climbing a 15% hill or on a long -4% down grade.

I think what it could be useful for is evaluating your form and how small changes could change effort at a given pace, however this is something that is done over the course of a few weeks and IMHO not worth dropping $200 on. I also think it *could* be potentially useful for trail running, but the trail runners I know (including two elite-level athletes) just go off of perceived effort than anything else.

Now, you're probably going to get some Stryd rep who responds here trying to discredit what I say - the reality is that it's their job. Knowing a former Stryd employee, we've had lengthy discussions about the product. What it boils down to is that it's a neat concept, but is just another metric that doesn't have as much of an effect as it does for cycling. A lot of their "reviews" by sponsored athletes saying it helped pace them could similarly be done with HR based racing if they wanted.

I have a stryd, but almost sold it. So I'm definitely not firm on it one way or the other. But this is a poor example. In cycling time trials we use best bike split to help us determine when we should push harder and when we should back off to achieve the overall fastest time. The same thing should be done running. Have a different target power for downhills, uphills & flats that will result in your overall fastest time. I think it's main usefulness in racing would be to hold yourself back on the hills so you don't burn unnecessary matches.

I decided to keep it because I like the instantaneous response it gives during intervals, whereas the GPS is always lagging - sometimes considerably. I hardly ever run on the track so can't check pace every 100-200m. I can also see immediately if my effort is starting to drop off. It's a useful tool. Whether it's worth the cost is debatable.

The hard part is knowing exactly what your supposed wattage is going to be before the race. Things like weight, form, weather, etc can all change effort levels on running. I know there's calculators out there, but they aren't 100%. I was basing my original comment on someone keeping the same baseline wattage over the entire race. I guess if you break it down into uphill/flat/downhill that it could be potentially usable there.

Again, the biggest issue is that power =\= pace, and I don't really know any runners out there that care that they averaged 300W 3:02 for the race, but rather they ran a PR of 2:59 and qualified for Boston.

Even worse, at the elite and sub-elite levels, you're competing for place, not overall wattage. So yes, sometimes you need to put in a surge for 400m or so in the middle of the race if you want to win.

How's that different than cycling? A cyclists doesn't care that he put out 300 watts for a TT, he only cares about his time.


Again, same as a bike race

Again, cyclists are locked in to pedals doing the same motions regardless of terrain. Runners form changes significantly based on terrain and it's not equal. Because cyclists are locked in with the same motion, it's much easier to train on power because it remains consistent. That's why I can go do a 12 mile climb here in CO and have it be an awesome workout, even though I was only going 12 mph. Meanwhile, if I ran 6 miles up the same 5% incline at 6MPH, it's not going to be the same type of workout as if I did 6 miles at 10MPH on a flat track as my form is completely different, stride is shorter and I'm working a different set of muscles.

Weather is also a much more significant factor in cycling than running. A 5 MPH headwind vs a 5MPH tailwind could be say a 10% difference in speed on the bike. That same wind might be only 1-2% on the run.

Also, I never said power was always useful or useless for cycling racing. I'm coming from a running perspective of why it isn't all that useful.

Do you claim that producing power up a hill is the same as producing power on the flat, on a bike? How about cadence and muscles?

Well, cadence is a function of what gears you choose....

So let us take a 25% incline as an example. You're on a 53/39 with 12-25 in the rear. Do you think your form would look good?

I love when people need to stretch reality to have a poor attempt at trying to make a point. For 99.9% of use cases, that isn't going to happen and you know that. 250W at 90RPM for is going up a 7% incline to be very similar to 250W at 90RPM with a 0% incline.

A simple 1-2% incline or decline can make major changes to your running form, and you know that.

Good try at a fake argument.

You are shifting the goalpost. My point was in regards to your contention that power =/= speed. Of course it does, even more so in running than cycling, as external factors influence your running pace less than they do speed on the bike. In fact, one of the best arguments against running with power is that it is such a close proxy for pace, that you can just use pace.

In terms of your marathon example, with your 300 watt runner. If 300 watts is the most he can average over a marathon, then he's not a sub 3 hr marathoner. If he can put out more than 300 watts, then he paced it wrong. It's not like all you have to do to run a sub 3 marathon is just run 6:50 miles. You also have to be capable of running 6:50 miles for 3 hours. The same is true for power, if it takes you 310 watts to run sub 3, then you need to be able to average 310 watts for 3 hours.

Power might = speed in a controlled environment, like a treadmill or a track. But a 2% grade might require an extra 10% power to maintain the same speed. Someone running via power would slow down 10% to maintain that power number. The reality is that few races are pancake flat with no environmental factors. I think the answer I've heard from Stryd reps before is that you need to put the course profile in and then run the course to the profile's power curves, which, let's be honest here, isn't going to happen during a race for most people.

I agree with the bolded part of your post, assuming flat.

The 2nd paragraph of your post, we're agreeing here. My point was that there are a lot of factors that go into running a marathon. If you're running by pace, you know where you stand against the clock and your goal. If you're running by power, you might miss that goal, even if you were capable of it because that day, there happened to be a slight headwind that made a few miles slower (for a given power number). Meanwhile, had you run by pace, you might have run 315W for 10 minutes, but kept pace and hit the time goal.

The whole point is that I don't see a clear advantage to run training with power and it has the potential for many issues if you race with it.

This is a strong argument FOR running with power, so that you don't overextend yourselves on hills, thereby pacing better and getting a faster time.



If he could have ran harder, he should have. You don't run a marathon to get a time you like, you run it to get the best time possible, and the only way to do that is to pace it optimally.

The assumption is that overextending for a short period is bad, and it isn't.

As far as if they should have run faster, I agree - but power is an abritrary number when you're competing for a time.

Keep it simple. Pace works better and is easier to understand and adapt than power for most people.

So, I think this is the nub of the question as to whether it makes sense to run with power or not: Is power a useful tool in helping to pace your effort to finish in the optimal time? Clearly Caverunner doesn't think so, and you disagree with him, and I appreciate both of your opinions.

Perhaps it's just the optimist in me that loves new data/gear to play with, but conceptually MRid's argument seems to make more sense to me than Caverunner's. I get Caveman's point, we run races to finish within a goal time (or win) not to hit a specific power target. But that's kind of overly focusing on the outcome rather than the process. At the end of the day, the runner's body has to deliver a certain amount of output. It will either happen or it won't. If this hypothetical 3hr marathoner we've been discussing needs to average 310 watts (due to terrain or whatever) to hit a 3 hour marathon, but the best his body can do is 300 watts, he's going to miss his 3 hour target either way - whether he runs to a power target (which is too low) or runs to a set pace (which is too fast to sustain).

So what this really comes down to, is.... is power a helpful data-point in addition to pace/HR in order to race the optimal race.

We know from cycling, cross country skiing, and many other endurance sports, that athletes perform better if we keep VI low, especially over longer distances races. So why wouldn't this be the case in marathon running as well?

Nothing about running with power suggests you should run a marathon at a flat power target -- quads be damned on the downhills. Much the same way, no one rides a hilly TT at a flat power. We know you have to push a little harder on uphills and rest a little more on downhills/tailwinds because at a certain point the drag makes pedaling harder futile.

I have no useful, real time quantitative way to assess how deep into the red on a hill when running. So intuitively, it seems like running power should be a useful datapoint, hence my question.

Having said all the above, I think we can table the hypothetical questions about whether it's useful or not.

I'd be more interested to hear specific examples/testamonials from people who have trained with power. What were it's shortcomings, if any? How did it help, if at all? What would you advise someone who was considering giving it a go?




Thanks exxxviii. Any other tips and tricks you can share about how you've found power to be useful? In the longer races, what did you do specifically that made the power data helpful (e.g., hold back to stay out of red line on hills, push harder on flats, etc.)? How did you figure out how to use it -- setting your uphill/flat/downhill target power zones for longer races, for example?

One challenge that Caverunner mentioned which makes a lot of sense to me is given that form/economy deteriorates over the course of a race, I suspect you'd have to lift power to stay on target pace which might keep you from running as fast as you otherwise might. How has that manifested in real world experience? Do you end up running positive splits which result in a faster overall time, or do you hold pace steady and just know you're going to finish the race at the top end of your target wattage "zone"?

I do use power and I like it, but mostly because I like data. I have paced stand alone runs and tri runs using power, formulating a power target based off percentage of FTP, and it's worked well for me.

That being said, if most of your runs are flat then everything I've done with power, I could have done with pace. So in that regard, I'm not sure how much it helps. If you have hilly courses on your schedule, then I do think it's useful.

As Sean H alluded to, you generally get a snappier response from your power meter than you will from GPS, so that can be beneficial.


Short answer, I like pacing with power, so I'm happy with my Stryd, but in my experience it can probably be done just as effectively using pace in most situations.

Thanks MRid.

Well, I live in San Francisco. So any run I do of reasonable length is going to be hilly. What initially attracted me to the idea, actually, was on "easy" runs with hills, I often find myself pushing into what feels like Z2/3 and thus ending up with too much training stress. Then I started thinking, the same principals would seem to apply in longer races -- accumulating too much stress too early in races.

It's been around 10 years since I ran with a footpod for pace but I remember it being pretty inaccurate. So this Stryd will actually make my Garmin pace MORE accurate / faster to respond to changes in pace? That would also be nice, for fartlek workouts and such, where I find I sometimes accelerate too much due to GPS lag.

And I love It when people aren't able to see the flaws in an argument they make, then ridicule you when you put it in such a ridiculous context that even they are able to see it. So to clarify: It was not an attempt to stretch reality but to make you understand that though the effects aren't as pronounced in cycling as they are in running, they are still there. That you moderate your previous statement to "up to x %" makes it a different discussion, but that is typically something people do when someone points out that their argument isn't generic.

So yes, cadence drops when you climb in cycling as well as in running. I was not trying to fake that argument. I don't have to, because it is true. That you can rectify this by lowering your gears only holds to a certain point. Sure it holds for gentle climbs, but that was not your statement.

So good job trying to move the goal posts and ridicule me at the same time. Moreover, you use your quads, your glutes and your calves more on a climb than on a flat in cycling as well as in running.

None of your "points" against running power vs cycling power are valid. You wouldn't try to hold flat power going downhill, nor uphill. If you do, the problem is not with the gadget, but rather with you as a user. Why wouldn't a biker try to hold x watts at all points in a race if a runner would? In running you probably pay more for every effort (due to impact) which is yet another argument FOR running with power, not against it.

"Running power is too complicated for Average Joe" is really the only argument you have going for you, and I don't think you have tried to make that yet.