Sprint power on trainer vs. road [Archive]

View Full Version : Sprint power on trainer vs. road

Pages : [1] 2 3

velomanct

i recently got a power tap pro and i am riding my kurt kinetic trainer this winter. has anyone noticed that they can hit a higher max watts outside than on the trainer? i can do about 50-100 more watts outside.
i am thinking this is due to not being able to sway the bike while pulling on the bars while sprinting, when on the trainer.

also, does anybody have the numbers on what kind of power top level espoir age track racers can do in a sprint? like max watts and ave watts for a 200meter sprint.

ric_stern/RST

Originally posted by velomanct
i recently got a power tap pro and i am riding my kurt kinetic trainer this winter. has anyone noticed that they can hit a higher max watts outside than on the trainer? i can do about 50-100 more watts outside.
i am thinking this is due to not being able to sway the bike while pulling on the bars while sprinting, when on the trainer.

also, does anybody have the numbers on what kind of power top level espoir age track racers can do in a sprint? like max watts and ave watts for a 200meter sprint.

Although i have no experience with the trainer you mention, it's likely that most (commercially available, but probably not all) trainers cannot generate enough resistance for good sprinters to reach their peak power.

furthermore, as noted, you can generally generate more power when out of the saddle, and also if you sprint at the base of a hill.

world class (male) track sprinters are in the region of 1800 to 2300 W. At very high levels with very fast cadences the PT may not pick up all the data (for a peak reading) -- for this you'd need a minimum of an SRM Pro. Don't forget to set the PT to the highest recording level (1-sec).

Ric

andrewbradley

Originally posted by velomanct
i recently got a power tap pro and i am riding my kurt kinetic trainer this winter. has anyone noticed that they can hit a higher max watts outside than on the trainer? i can do about 50-100 more watts outside.
i am thinking this is due to not being able to sway the bike while pulling on the bars while sprinting, when on the trainer.

I reckon that this could be about right for the difference between out of saddle power and in-saddle power.
If there was no difference why would road sprinters remain out of saddle all the way to the line in what seems an aerodynamically inferior position?

Swaying the bike (regarded as unnecessary by some) could allow you to input perhaps 50W of power. The legs muscles are used over different ranges and with different contraction speeed profiles and I speculate these could be closer to "ideal" for maximum power.
Mathematical modellers have predicted very significant max-power gains if the muscles could be brought close to their ideal contraction speed profiles. (Only models though!)

2LAP

Billsworld

ric_stern/RST

It tends to be that your speed is still increasing even as your power is decreasing. In other words peak power occurs prior to peak speed.

ric

The worlds fastest look like they are seated most of the way.....Question, lets say the top speed in a sprint was 40mph. are the max watts numbers that you noted 1800-2300 based on acceleration up to 40mph or the brief time spent at max speed. (sorry my powertap is on the way) ......................I also have a kurt trainer, and my top speed numbers are about the same on the road, but acceleration is a waste of time due to slipage. Thanks BP

Billsworld

Thank you. I seem to have plenty of leg speed in small gears, but its not giving me overall speed. I find I can go faster in 90+ gears mashing away. it feels like i am riding in mud but i am going faster??? I am exited for the power tap.....I think the less expensive trainers might be best for just spinning and some interval training. Thanks againIt tends to be that your speed is still increasing even as your power is decreasing. In other words peak power occurs prior to peak speed.

ric

Squint

Thank you. I seem to have plenty of leg speed in small gears, but its not giving me overall speed. I find I can go faster in 90+ gears mashing away. it feels like i am riding in mud but i am going faster??? I am exited for the power tap.....I think the less expensive trainers might be best for just spinning and some interval training. Thanks again

Power is what makes the bike go faster, not cadence. Generating power involves cadence and force on the pedals.

I see a lot of people imitating a certain TdF winner's cadence but none imitating his force on pedals so in the end they also lack his power.

Billsworld

I feel I am more suited to sprinting, thats why I am trying to pic peoples brains on the subject. I think I am going to go to an on line coach. I stared cycling this year after 20 yrs of powerlifting. ( cholesterol problem) I agree with what you are saying on power. I never knew that my knees could get so sore from mashing those biger gears though. I did a few crits last year and had fun and as the year went on my road cadence kept getting higher(to protect my knees) as my power went the other way. Thanks BPPower is what makes the bike go faster, not cadence. Generating power involves cadence and force on the pedals.

I see a lot of people imitating a certain TdF winner's cadence but none imitating his force on pedals so in the end they also lack his power.

velomanct

The worlds fastest look like they are seated most of the way.....Question, lets say the top speed in a sprint was 40mph. are the max watts numbers that you noted 1800-2300 based on acceleration up to 40mph or the brief time spent at max speed. (sorry my powertap is on the way) ......................I also have a kurt trainer, and my top speed numbers are about the same on the road, but acceleration is a waste of time due to slipage. Thanks BP
It's been awhile since I started this topic and I learned a lot with my powertap. Peak power is ALWAYS achieved during the acceleration of a sprint, in the first 3 seconds if you go full out from the start. I have hit around 2000 peak this summer, but can't do a good 200meter to save my life (best ~11.8s), as my power at the end of such a sprint would be ~800w. I did work on hill sprints too, got a PB of 1500w average for 20seconds. I wish so bad that I could do that power in a 200m, but it must be my poor leg speed. So I always say my jump is my best, but as soon as the cadence goes above 120rpms I loose lots of power. I have noticed that my seated power is usually around 200w below standing power too. I discovered a fun way to work on top end/cadence - downhill sprints. Even in top gear 53x12, I can get that over 150rpms on a decent hill. The fun part is, I am hauling a$$ (over 50mph), but it's really good for training power at high leg speed. I just despise doing a flat 200m sprint, it's no fun. If it's not fun, you won't do them, and won't improve. Or if you make yourself do them, you won't really be motivated enough to push yourself the most. Downhill sprints rock! I'm such a speed junkie, lol.
I also got rid of the powertap. I got too caught up in the numbers and decided to just ride and have fun. The only thing I look at now is top speed :-D
One of the best workouts I did to work on my jump was go down a small hill that leads into an uphill. That way you can thrash the bike like a gorilla without having to shift or being undergeared. I have gone up short hills doing this at speeds that were unimaginable to me a few years ago, like 32mph up 6%. That was one of my favorite workouts.
I did some sprints on the kurt trainer, but not in a while. I don't like having my bike fixed in a position. I injured my knee a couple times doing sprints on the trainer. There was some tire slippage, but you just have to tighten the roller harder, like 3 rotations after tire contract. I must say, the kurt kinetic trainer is likely one of the best ones for doing sprints, you will never spin that thing out!

frenchyge

I discovered a fun way to work on top end/cadence - downhill sprints. Even in top gear 53x12, I can get that over 150rpms on a decent hill. The fun part is, I am hauling a$$ (over 50mph), but it's really good for training power at high leg speed.
What about small chainring sprints for this? If you're just working on leg speed, is there really a need to be doing 50 mph down a hill?

As a separate, but related, question: do the best sprinters turn >150rpm cadence during their sprints (road sprinters, mostly)? I would think it would be difficult to coordinate the legs and arm pulling at that speed.

Billsworld

Thanks for the reply. Your power tap numbers would suggest that you doing pretty well. I am thinking about buying an srm and converting a schwinn airdyne into a chain driven airgometer.(no slip) I know I am a bit twisted... If my memory serves,I think I am a bit older than you and most likely have a little bit more cash to waste. I think the age group wr 45-50 is 11.2, and I am a cocky s.o.b., so thats my goal, I am just not sure quite how fast that would need to be on the street( i know totaly different) which is where i will do about 90% of my training.PB 38mph 150rpm 48x14... Back to the subject...I read that M. Nothstien did 2200 watts 50x14 at 160 rpm at his best 49mph YIKES!!! When he says that, he is talking the flying 200 I think. Wouldnt he already be at or near max speed (and not 2200watts) at the begining of the 200 and be hanging on from there??I think thats where I am confused about watt output in that event. My guess is he is seated for most of his last 200m too, or was the watts he was refering to during the wind. WATTS UP??? Thanks BPIt's been awhile since I started this topic and I learned a lot with my powertap. Peak power is ALWAYS achieved during the acceleration of a sprint, in the first 3 seconds if you go full out from the start. I have hit around 2000 peak this summer, but can't do a good 200meter to save my life (best ~11.8s), as my power at the end of such a sprint would be ~800w. I did work on hill sprints too, got a PB of 1500w average for 20seconds. I wish so bad that I could do that power in a 200m, but it must be my poor leg speed. So I always say my jump is my best, but as soon as the cadence goes above 120rpms I loose lots of power. I have noticed that my seated power is usually around 200w below standing power too. I discovered a fun way to work on top end/cadence - downhill sprints. Even in top gear 53x12, I can get that over 150rpms on a decent hill. The fun part is, I am hauling a$$ (over 50mph), but it's really good for training power at high leg speed. I just despise doing a flat 200m sprint, it's no fun. If it's not fun, you won't do them, and won't improve. Or if you make yourself do them, you won't really be motivated enough to push yourself the most. Downhill sprints rock! I'm such a speed junkie, lol.
I also got rid of the powertap. I got too caught up in the numbers and decided to just ride and have fun. The only thing I look at now is top speed :-D
One of the best workouts I did to work on my jump was go down a small hill that leads into an uphill. That way you can thrash the bike like a gorilla without having to shift or being undergeared. I have gone up short hills doing this at speeds that were unimaginable to me a few years ago, like 32mph up 6%. That was one of my favorite workouts.
I did some sprints on the kurt trainer, but not in a while. I don't like having my bike fixed in a position. I injured my knee a couple times doing sprints on the trainer. There was some tire slippage, but you just have to tighten the roller harder, like 3 rotations after tire contract. I must say, the kurt kinetic trainer is likely one of the best ones for doing sprints, you will never spin that thing out!

velomanct

What about small chainring sprints for this? If you're just working on leg speed, is there really a need to be doing 50 mph down a hill?

As a separate, but related, question: do the best sprinters turn >150rpm cadence during their sprints (road sprinters, mostly)? I would think it would be difficult to coordinate the legs and arm pulling at that speed.

small chainring sprints are fine for developing JUST leg speed. but there is a difference between 160rpms in the small ring and 160rpms in your sprint gear - power. Sprinting downhills would have the simular effect of doing 200m sprints, the difference like I said above, is that it's a lot more FUN. That is a big factor for me.

I can do 220rpms on the road in my granny gear, but I can't ride a sub 11.8 200m. See the difference? It's all about high sustained power at high cadences (140-160rpms), for 200m sprints.

Road sprinters don't go much above ~125rpms during flat sprints, because they got gears, and they are standing not seated. Don't start comparing road sprints to track sprints, they are way different.
As for sprinting at high cadences on the track, it's always in the saddle so there is very little pulling on the bars, and it's not an issue. But even on a road bike, it's possible to ride at 160+rpms out of the saddle, although its very inefficient.

ric_stern/RST

I feel I am more suited to sprinting, thats why I am trying to pic peoples brains on the subject. I think I am going to go to an on line coach. I stared cycling this year after 20 yrs of powerlifting. ( cholesterol problem) I agree with what you are saying on power. I never knew that my knees could get so sore from mashing those biger gears though. I did a few crits last year and had fun and as the year went on my road cadence kept getting higher(to protect my knees) as my power went the other way. Thanks BP

Bill, feel free to give me a shout -- i've coached world class 200-m and 1-km TT riders,

cheers
ric

velomanct

Thanks for the reply. Your power tap numbers would suggest that you doing pretty well. I am thinking about buying an srm and converting a schwinn airdyne into a chain driven airgometer.(no slip) I know I am a bit twisted... If my memory serves,I think I am a bit older than you and most likely have a little bit more cash to waste. I think the age group wr 45-50 is 11.2, and I am a cocky s.o.b., so thats my goal, I am just not sure quite how fast that would need to be on the street( i know totaly different) which is where i will do about 90% of my training.PB 38mph 150rpm 48x14... Back to the subject...I read that M. Nothstien did 2200 watts 50x14 at 160 rpm at his best 49mph YIKES!!! When he says that, he is talking the flying 200 I think. Wouldnt he already be at or near max speed (and not 2200watts) at the begining of the 200 and be hanging on from there??I think thats where I am confused about watt output in that event. My guess is he is seated for most of his last 200m too, or was the watts he was refering to during the wind. WATTS UP??? Thanks BP

"...I read that M. Nothstien did 2200 watts 50x14 at 160 rpm at his best 49mph"

You can't take that statement word for word. Marty said his max watts was 2200, I am assuming that is NOT during any part of a 200m TT. He likely hit those watts during a match sprint where he jumped hard, or during a simular effort. It is not smart to go 100% full out explosive during your windup for a 200m TT, you use too much gas. I also highly doubt he hit his peak watts at 160rpms, I hit my peak at 115rpms. And he would certainly not be at peak power at top speed. The 49mph- who knows where that was. On the road, track, leadout, it makes a big difference. All I know is that I can't get above 40mph on a dead flat windless road.
Remember, the 200m TT is a ~20second effort, not 10, 11, 12 seconds. It takes a lot of work to get up to top speed before you hit the line. I hate how so many people disregard this, although I think you understand.

This summer I spent a lot of time doing sprints and learned how much difference in intensity there is between just a "road sprint" and a real full out explosive jump of ~4-5seconds. When I hit my best peak watts, it's during one of those 5 second explosive bursts where I would thrash the bike like a gorilla, lol. I couldn't maintain that level of effort for more than 5 seconds. So you can see that I would never come close to a real peak watts during a 200m sprint. During a typical 200m I would peak at ~1500 when I jumped.
When you do hundreds and hundreds of sprints you can really get in tune with the varying intensities levels within what would be considered a sprint. A 5 second jump is TOTALLY different than a 20 second hill sprint or 200m.

Now, I sometimes read how riders say they did a sprint up that 1/2mile hill. :eek: Or how runners call a 5k run a sprint run. yeh, I hate that. Sprinting is not anything over 30 seconds, tops. Even 30 seconds is a damn long sprint, barely a sprint in my book. :D

I did okay with peak numbers, but that's almost the only thing I trained this summer, to see how high I could get. I would like to someday get around 2500. I think it's possible in a few years, if I put aside all those long road rides ;)
So I plan on owning a powermeter again someday. But I want to get more powerful before that. I just think it would be super cool to legitimetly say I peak at 2500 :D
I am only 20 yrs old btw, so yes I am a bit younger than you!

One thing to add. I garantee you that Marty was capable or more than 2200w peak for one second. Probally in the neighborhood of 2500 if he really tried in ideal conditions, gearing.
Watts numbers don't mean much unless the duration and conditions are specified.

BTW, have you seen the power profile chart? My best performance was 21w/kg for 5 seconds. (at 85kg) I assume Marty would be 24w/kg, at 100kg, which would be 2400w, and therefore his true one second peak would be ~2600w, a lot more than 2200.
Too many numbers! Just go out and sprint! :D

frenchyge

I can do 220rpms on the road in my granny gear, but I can't ride a sub 11.8 200m. See the difference? It's all about high sustained power at high cadences (140-160rpms), for 200m sprints.
Oh yeah. As an ~1100w guy, I'm fully aware of the difference in power. :) Your downhill sprints are using gravity to offset the high power requirement, and I was just thinking that 'simulating' a sprint, but in a lower gear, might do the same thing for one's form/technique.

Road sprinters don't go much above ~125rpms during flat sprints, because they got gears, and they are standing not seated. Don't start comparing road sprints to track sprints, they are way different.Sure. Not trying to compare, I'm just a roadie looking for some sprint advice that might help me out. You sound very knowledgeable/experienced in the ways of sprinting, can you give any tips or drills that might help with sprinting form/technique? I know I also need to work on my max power output if I ever want to see 40mph. ;) Thanks.

velomanct

Oh yeah. As an ~1100w guy, I'm fully aware of the difference in power. :) Your downhill sprints are using gravity to offset the high power requirement, and I was just thinking that 'simulating' a sprint, but in a lower gear, might do the same thing for one's form/technique.

Sure. Not trying to compare, I'm just a roadie looking for some sprint advice that might help me out. You sound very knowledgeable/experienced in the ways of sprinting, can you give any tips or drills that might help with sprinting form/technique? I know I also need to work on my max power output if I ever want to see 40mph. ;) Thanks.

Do you see my point? I said that stating numbers is useless unless you state the conditions and duration of the sprint. 1100w? for how long? seated, standing, big gear, small gear, uphill, flat? It really does make a big difference.
1100w average for the final 12 seconds of a 200m 'track' sprint is very good. 1100w peak for one second is not very good. But then again, what's your weight?

Just so you know, peak power has very little to do with top speed, especially if you are not givin a leadout. If you want to work on your top speed, I would suggest a good mix sprints. It would be a good idea to do your training with some friends, it will make it a lot more fun and you can push yourself harder.
I would do everything from hill sprints to downhill sprints to small ring sprints, seated sprints, standing starts. Your ultimate goal is raise the average power you can do for a 15-20 second sprint. Don't do too much work on short jumps, it won't help you that much, all though it is nice to have a good jump.

I did this week of training for working on my acceleration, and got improvements with it.
mon- off
tues- 1hr, six 6 second sprints in my 39x21, alternating standing/seated. followed by plyometrics and heavy weights.
wed- 1hr easy
thurs- 1hr, six 6 second sprints in a big gear (two gears harder than I would normally use), alternate standing/seated. followed by a different rep/set scheme with heavy weights on different lifts.
fri- off or easy
sat- set personal bests. no kidding, my jump improved a lot. I was so in tune with my sprint that I could tell imediately if I was hitting a new PB peak wattage during the sprint. After some time dedicating my training to this, it really felt good to just go balls out. My fast twitch muscles were primed well.
Now, I haven't done too much of this training lately, and I can feel I am weaker from the long roadie efforts.

Another thing you can add in once you get into sprint training is some explosive weight lifts, like clean pulls. Do these a few hours before your bike workout. It really primes the nervous system. This is what lead to my best peak numbers this past summer. I felt so damn strong during those first sprints, it was amazing. Too bad it wears off as you fatigue.
I wouldn't worry about doing these 'pre-ride' lifts untill you have been sprint training for at least 3 months.
Also, during this time I did zero endurance work. The only thing 'endurance' I did was being on my bike for an hour or two. All the riding inbetween sprints, I was at like 110bpm.

I wish I had some riding buddies I could train with, no one around here wants to sprint :(

As for form/technique, I personally don't pay much attention to it. During sprints you need to have 100% concentration on killing the pedals. Sprinting requires a lot of aggression. If you are lazy or just not energized you won't outsprint that 10lb dog. I really think the best way to train sprints if with someone who is at least your ability level. If you can't find anyone, just try to keep up with traffic after a red light, works for me! Want to work on kilo power? On a side road, when a car passes, see how long you can keep them in sight ;) yeh that stuff hurts.

As for me, I am going to continue doing my downhill sprints at this time. Check out my videos in the bike cafe forum. 60mph is a lot more fun than 38. :D
http://www.cyclingforums.com/t-292701-15-2.html
Horton Hill is sick. Dropped 400ft elevation in less than 30 seconds. :eek:
If that road were straight and smooth, I would have been well into the 60s.

frenchyge

As for me, I am going to continue doing my downhill sprints at this time. Check out my videos in the bike cafe forum. 60mph is a lot more fun than 38. :D
http://www.cyclingforums.com/t-292701-15-2.html
Horton Hill is sick. Dropped 400ft elevation in less than 30 seconds. :eek:
If that road were straight and smooth, I would have been well into the 60s.
Jeez, you've got some ballz going that fast down those roads. Too many soccer moms and football dads in SUVs around here to try a stunt like that.

Thanks for the tips.

Billsworld

What your saying is what I am discovering . I wasnt really comparing road to track sprinting, I would however like to see how fast a good track guy would go on the street just for a point of reference........... Wouldnt a flat road be more like a track?? I have noticed that alot of guys do big gear slow cadence rides/sprints to build power. Kind of like weight traing on the bike .That doesnt make sense to me at all, but there are some real fast guys that do it. FYI the guys in NH that are racing on the banked go cart track said they are open to Sat. night instead of wed. Ill be checking it out next season. Thanks BPsmall chainring sprints are fine for developing JUST leg speed. but there is a difference between 160rpms in the small ring and 160rpms in your sprint gear - power. Sprinting downhills would have the simular effect of doing 200m sprints, the difference like I said above, is that it's a lot more FUN. That is a big factor for me.

I can do 220rpms on the road in my granny gear, but I can't ride a sub 11.8 200m. See the difference? It's all about high sustained power at high cadences (140-160rpms), for 200m sprints.

Road sprinters don't go much above ~125rpms during flat sprints, because they got gears, and they are standing not seated. Don't start comparing road sprints to track sprints, they are way different.
As for sprinting at high cadences on the track, it's always in the saddle so there is very little pulling on the bars, and it's not an issue. But even on a road bike, it's possible to ride at 160+rpms out of the saddle, although its very inefficient.

jeff828

I have noticed that alot of guys do big gear slow cadence rides/sprints to build power. Kind of like weight traing on the bike .That doesnt make sense to me at all, but there are some real fast guys that do it.BP

I have started doing big gear slow cadence work myself and it DOES work, started last year and it definitly increased my aerobic & cruise speed. Look at it this way, if you spin a 39x16 at 100rpm for a mile, then you ride the same mile in a 53x14 at 80rpm, which one do you think will build more muscle strength or puts more strain on the muscle. Theres very little resistance when spinning.

Or ride certain loop for 1 hour in 39x17 at 100rpm, Then ride the same course for an hour in 53x15 at 17-19mph only, dont hammer it. Tell me which workout tired your legs out, try it for real as a test.

I did 53x17 at 17-19mph only, for a season, rode totally aerobic, just let time take its toll. Started with an hour, now I can ride it for 3-4 hours. On the smaller grades i just let the cadence drop a little more, i just rode it, did not let it get to were your fighting the gear or get anywhere close to threshold.

Im a natural sprinter came from bmx, favorite gear to sprint 53x16, or when my cadence is 100-110 can crank out 150rpms, usually get a big jump on the guys starting in 53x14,13. If i am going to spin out i always have the option to then shift to bigger gear. It doesnt take as much muscle to snap a lighter gear.