What max power does these legs have?

Hello all.

Got a question for y’all. I’m at the heavier end of the cycling scale. My current weight is roughly around 89kg. I’m somewhat of a sprinter, I know this from my school athletics days etc and I do love to grind a big gear and rev it up.
Uh so my question is I would like to know roughly what my kinda max sprint is. I’m flowing TR plans and I’m not deviating all. But I am itching to sprint. I wanna test what I have. I have a wahoo kickr core it’s my only source of measuring power, so it would have to be indoors. Not ideally but hey. What workouts are there to test max sprints or any other form of testing via the TR app?

Happy winter training.

My personal opinion is that max sprints should be saved for outside. I don’t have a particularly big sprint at 1350w 5 sec but I wouldn’t want to risk putting my bike/trainer through that.

The other issue here is that knowing this number doesn’t really help you achieve anything, unless you plan on training your sprint, and that takes me back to my first point.

If you want to look at sprint intervals then just go to the workouts section on the website and search “sprint” or select “burst” from the filters on the left. I had a very quick look and most of these workouts don’t require a sprint of more than 50% of my max, so the highest I found was about 700w.

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I’d also add, and I don’t mean to be rude here, that being bigger doesn’t correlate with being a sprinter. I may be way off-base here but this is a common misconception which has been addressed, in passing, on the podcast a few times.

Personally I’d recommend continuing to sprint outdoors when you feel necessary, but also to focus on building your FTP (a higher FTP means you can save more power for the sprint at the end). This will be useful whether you race or not, but if you aren’t currently racing, then focus on being an all-rounder or on strengths specific to your goals (gran fondo, sportive, distance goal etc) and figure out your speciality during competition.

I’m around OP weight and find that sprinting on a trainer (kickr snap) is limiting me as I can’t move freely and afraid to break something. As mentioned above, I also agree, that it is best to leave these to do outside. I also feel I may be maxing out the Snap as it is rated for 1500w, haven’t seen it reading ever higher. Perhaps accuracy at that wattage could be far from ideal.

Well I think you can just set any workout to ‘resistance’ (vs ‘erg’) and have a go. So pick something simple like recess and let it unwind a little!

I will, however, offer a few caveats:

1.) Try a couple of 85% or 95% sprint efforts first. Just to test the waters. Sprinting on a trainer isn’t the same as sprinting outdoors. You can crash on your trainer if you aren’t careful in a sprint! :smiley: Or worse, break your bike. So take a cautious approach.

2.) If you have a pretty solid sprint the mechanical limits of your trainer will put an upper boundary to what you can accomplish indoors. I’m not 100% familiar with that trainer’s max power spec but somebody on the forum will be able to quote it from memory, I’m sure.

Let us know what you crank out.

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The main thing to remember is erg mode is no use to you for sprinting. My advice is to do “free ride 60” and switch the kickr mode to “standard”. You can experiment with the level setting but probably start on 0 or 1. Warm up for 10 minutes, then go to the big ring and middle of cassette. Roll at 60 rpm and then go all-out for 10 seconds and see what happens. If you spin the gear out, try a higher gear and/or a higher level setting. If you never get on top of it shift down. Try a few 10, 20, 30 second sprints with looong (~8-10 minutes) recoveries where you just spin at 40% FTP.

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::smiling_imp:: Yeah. Try the Burgomaster sprint protocol. You’ll love it.

Yep, just look at Nate. But also from my experiance the same, this summer I was 85kg FTP 340w, Max 5 second sprint 1200w.
Team mate, >70kg (Don’t know FTP but considerably less than mine) Max 5 second sprint 1400w.

I even did a few weeks of Sprint training and that is where I got to, just don’t have a lot of those fast twitch fibres.

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I’m not sure I agree with that though. A few weeks training is hardly cause for writing yourself off as a sprinter.

Average riders are nowhere near their genetic potential so classifying yourself as a sprinter or climber is largely meaningless in the subject of genetics or muscle fibre composition. More often that not it only highlights what kind of riding that rider likes to do, or has accidentally trained in to themself.

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Sorry I should have been more specific I did 6 weeks of 1-2 sprint sessions a week I improved my 20s sprint from around 800w to 1000w and my 5s sprint from 1000w to 1200w. Again remember during this time I was well trainined with my FTP about 340w weight 85kg, 4w/kg.

I’m not suggesting these are terrible numbers, but comparatively they are quite low.

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I see what you’re saying, but a 20-25% improvement after 6 weeks is pretty good. I think the majority of TR users, especially well trained ones would be delighted with that improvement!

Maybe you have reached a genetic limitation but I dare say, give it more time and you could become more of a sprinter if you wanted to be

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Dude absolutely avoid full gas sprints on the trainer. It’s just not worth risking cracking a seatstay. In the saddle sure but out the saddle not worth the risk in my opinion.

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On TR ‘Charing’ is a close approximation of the Burgomaster sprint protocol. Although 225% of 75% of MAP probably doesn’t qualify as an ‘all out effort’ for most. But, hey, it just goes to show you that if you can think of workout, TR probably already has it.

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Old’ish thread I know, but re sprinting, just get on with it.

Re weight, I’m def a heavyweight, 120kg & 6’5". I recently started indoor cycling - using a kickr core. Peak sprint I can achieve 1685W and the bike feels solid. Feet occasionally come unclipped but where I’ve previously flown off when thats happened sprinting outdoors, on a trainer its far more stable - just frustrating.

However my trainer seems to max at this - I cant for the life of me get 1 watt over 1685…but can hit that repeatedly.

Re testing your sprint - just ride any course - flatter the better and any time you want, just crank it out. I use Zwift and only splint when there is a sprint built into the lap but it’s simple enough. Then use strava to view the output. I’ve uploaded an output from today.

As someone has said - don’t be in erg mode.

The likelihood of braking a frame etc as a few have suggested is absurd. Compared to sprinting outdoors the frame hardly flexes at all compared to when on road, and less again compared to top sprinters - even if using a ‘wobble plate’ or what ever you want to call them - there are vids online showing how little the frame moves compared to when on road.

Anyway - make sure you update the board with how you get on.

All the best

I don’t know i always do a short sprint in the same place, where it is save and where i can see far ahead. I always try to do better, experiment with gear, improve form, and sometimes turn around rest 5 min and do it again. It is fun unfortunately i can only sprint for like 4 to 5 sec. In that place it is a bit uphill that i like a lot better then just a flat. I think my first sprints a year ago i did just crack 1000W now my best is around 1340W @73kg. I would trade it any day for 20W more on my ftp. Todays first sprint outside, wrong gear cadence was to low!

Was just a low intensity fun ride with a friend, but like i say in that place i always sprint for fun

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