Training & Nutrition - Rocking and "snaking" -- opinions?

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ratebeer
02-08-07, 11:59 AM
Some of the more rudimentary guides I've read say to avoid rocking in the saddle. Some pedaling efficiency guides also suggest keeping your butt in one place.

How is it then that when a pro is observed from behind, you see a lot of rocking and "snaking", an alternating contraction of the sides of the back? Dave Zabriskie is textbook for this in his TTs. I've only heard this simply explained by, "Oh, you'll see more of that from pros during climbs, sprints and time trials."

What's your feeling on this? It seems that these riders are deriving more power from the technique in a way that might raise work output at sub-lactate threshold.

It also appears that distributing work load to more muscle groups might reduce lactate production.


timmhaan
02-08-07, 12:04 PM
generally the rocking motion you see is a last ditch effort to squeeze any and all power out of their body that they can.

it's similar to weight lifting. when you're strong and the workload is manageable you can lift with good form. as the weight becomes almost unbearable, you naturally resort to using stabilizing muscles to help more and trying to swing the weight. in other words, the form deteriorates.

even lance has been seen rocking back and forth on the bike when he's almost at his limit.

ratebeer
02-08-07, 01:02 PM
generally the rocking motion you see is a last ditch effort to squeeze any and all power out of their body that they can.

it's similar to weight lifting. when you're strong and the workload is manageable you can lift with good form. as the weight becomes almost unbearable, you naturally resort to using stabilizing muscles to help more and trying to swing the weight. in other words, the form deteriorates.

even lance has been seen rocking back and forth on the bike when he's almost at his limit.

So it's bad?


slowandsteady
02-08-07, 01:41 PM
Not if it is all you have left.

Eatadonut
02-08-07, 01:50 PM
It's not "bad". But it's not good. You're trading efficiency (and therefore endurance) for power.

In a TT, this doesn't matter as much. In a tough climb, you may not have a choice if you want to win.

I think the reason it's so discouraged, even though pros do it, is because they know their bodies so much better (and their bodies are more reliable/consistent). If average joe's form collapses 10 miles from the end of his RR so he can push out those last 10 watts, he might not make it to the end. Mistakes like that are less likely with a professional. They'll happen, but not nearly as often.

timmhaan
02-08-07, 01:56 PM
not to mention that it's really really hard to keep proper form when you're within a few beats of your max heart rate and every single cell in your body is crying for you to stop. i think a little lapse of form is forgivable. ;)

ratebeer
02-08-07, 02:45 PM
not to mention that it's really really hard to keep proper form when you're within a few beats of your max heart rate and every single cell in your body is crying for you to stop. i think a little lapse of form is forgivable. ;)

I'm still wondering if this "bad form" might be intentional and advantageous and it's simply our idea of "proper form" that's wrong, at least as it pertains to power riding near LT?

If you have more muscles working on a load then you decrease lactate production. Reduce lactate production and you can increase max speed. I don't know if economy and efficiency suffer but they may.

grebletie
02-08-07, 05:09 PM
I'm still wondering if this "bad form" might be intentional and advantageous and it's simply our idea of "proper form" that's wrong, at least as it pertains to power riding near LT?

If you have more muscles working on a load then you decrease lactate production. Reduce lactate production and you can increase max speed. I don't know if economy and efficiency suffer but they may.
No, it's not intentional and advantageous. It's wasted motion that uses energy but fails to translate into meaningful power.

ratebeer
02-08-07, 05:25 PM
No, it's not intentional and advantageous. It's wasted motion that uses energy but fails to translate into meaningful power.

Hmmm... Tilting the pelvis over the pedal doesn't place more hip and lower torso weight into the downstroke?

I'm not saying you're wrong, just wondering if your source is your own power tests and/or research or something non-proprietary you can share with us? I'll do the reading. I promise. Just point me in the right direction.

slim_77
02-09-07, 04:15 AM
Hmmm... Tilting the pelvis over the pedal doesn't place more hip and lower torso weight into the downstroke?

I'm not saying you're wrong, just wondering if your source is your own power tests and/or research or something non-proprietary you can share with us? I'll do the reading. I promise. Just point me in the right direction.

More force in the downstroke is not "pedaling in circles" which is--most of the time--the most efficient pedaling technique (applying perpandicular force at 360*). Nevertheless, there is no such thing as bad form after winning a race...

If you are only training, form and technique may help you reach your goal more so than "mashing" even if it is slight because slight mashing also limits your muscle groups...why not opt for a more efficient technique than simply substitute one muscle group for another?

branman1986
02-09-07, 04:51 AM
How can moving your body all over the place NOT lead to wasted energy? I don't know why you need some scientific research for that. Sure it might put more weight over each pedal stroke, but clearly you're much less efficient. The extra power doesn't mysteriously appear, you have to force your upper body back and forth, which wastes energy.

ratebeer
02-09-07, 10:58 AM
From a Cervelo rider's (*chuckle*) fastest TdF time trial ever.
It looks like there are only periods when Dave tilts and/or snakes. Lance Armstrong does the same.

"KIll everybody!"
http://www.youtube.com/watch?v=8BD_RFR6PXA

ratebeer
02-09-07, 11:03 AM
It seems probable that efficiency is not as related to performance (time to finish) as average power over certain courses.

ratebeer
02-09-07, 11:11 AM
"When the bird does not agree with the book, believe the bird." -- birdwatcher's aphorism

Lance Armstrong's same prologue
http://www.youtube.com/watch?v=qz95I3cJQ_s

Eatadonut
02-09-07, 04:52 PM
How can moving your body all over the place NOT lead to wasted energy? I don't know why you need some scientific research for that. Sure it might put more weight over each pedal stroke, but clearly you're much less efficient. The extra power doesn't mysteriously appear, you have to force your upper body back and forth, which wastes energy.

I explained this earlier - it's not as efficient, but it's more powerful. At times, this tradeoff is OK.

VanceMac
02-09-07, 05:04 PM
I explained this earlier - it's not as efficient, but it's more powerful. At times, this tradeoff is OK.

Exactly. In the short term, it is an advantage. But big picture, it isn't the most efficient. I typically don't stand much on most climbs... but on the last climb of the day, I'll stand, rock, snake, flail, whatever. :)

Eatadonut
02-09-07, 05:10 PM
Exactly. In the short term, it is an advantage. But big picture, it isn't the most efficient. I typically don't stand much on most climbs... but on the last climb of the day, I'll stand, rock, snake, flail, whatever. :)

I'm sure that wasting air screaming curse words at the pavement is wasted energy, but it sure gets me over the hill ;)

branman1986
02-09-07, 05:11 PM
It seems probable that efficiency is not as related to performance (time to finish) as average power over certain courses.

exactly

ratebeer
02-09-07, 05:27 PM
I explained this earlier - it's not as efficient, but it's more powerful. At times, this tradeoff is OK.

I do still wonder though...

There are two primary power limiting mechanisms at play in a short time trial -- energy availability and inhibitory forces (lactic acid buildup primarily). The greatest of these is lactic acid buildup.

It's also well known that broadening muscular support for power loads decreases lactic acid production for the same load. Example: a rower produces less lactic acid by using the arms, lower back and legs instead of just the upper back, resulting in better performance times.

So I wonder if this power position, in addition to using more energy (inefficiently), produces the more potent race effect of reducing lactic acid production through muscular load sharing? Isolating muscles is good for efficiency. Sharing the load is good for power. TT times are typically strongly related to power.


It looks like I'm stuck on the the trainer for the rainy month... if I know myself well enough, I'll devise a layman's protocol (admittedly bad controls) to check sub-LT power output using different TT-style pedaling forms. Oh, this is going to hurt real bad! I look forward to headaches and blowing chunks. :D