Is the "right" pedal stroke over-rated?

[leftyfreak]

Originally Posted by Black Dog

This is true but lifting the leg is not about adding power from the lift, it is about reducing the load that the pushing leg has to overcome. This allows more power to be generated. That is why the elite riders push harder, they are not being as inhibited by the mass of the dead leg. This reduces fatigue and allows for greater power generation on top of the extra power that is produced from the lack of dead leg resistance during the pedal stroke. Also, extra training generally makes them more powerful regardless of any other factor at play.

It's all about efficiency in two ways.

First, if the right leg is on the upstroke, the activation of the hip flexor unloads the right pedal, reducing the load on the left glute, as has been mentioned.

Second, as Ti Designs has alluded to, the concept of reciprocal inhibition comes to play. The activation of the right hip flexor on the upstroke also causes the right glute to shut down. So this also means that the right glute is getting a chance to recover for a period of time during the pedal circle, rather than being under tension the whole time.

Fundamentally, it's about learning to use your muscles in the region of the pedal stroke where they will be most effective. It's not about some mythical "round" pedaling technique.

[Ti Designs]

Having done a bit of research myself, the one conclusion I keep returning to is that people make a lot of assumptions about what they're doing at the pedals - and a lot of those assumptions are wrong. Challenging those assumptions will result in one of three outcomes. The common one is anger and outrage - how can anyone not know how to pedal a bike? I then often get told how long they've been riding... The less common outcome is to entertain this idea that learning how to pedal might just be a good idea. The third outcome is that I'm wrong, so I built a test rig...

https://drive.google.com/file/d/0BzP...ew?usp=sharing

[MattTuck]

Originally Posted by Ti Designs

Having done a bit of research myself, the one conclusion I keep returning to is that people make a lot of assumptions about what they're doing at the pedals - and a lot of those assumptions are wrong. Challenging those assumptions will result in one of three outcomes. The common one is anger and outrage - how can anyone not know how to pedal a bike? I then often get told how long they've been riding... The less common outcome is to entertain this idea that learning how to pedal might just be a good idea. The third outcome is that I'm wrong, so I built a test rig...

https://drive.google.com/file/d/0BzP...ew?usp=sharing

That rig is impressive.

[Dead Man]

Originally Posted by Ti Designs

Having done a bit of research myself, the one conclusion I keep returning to is that people make a lot of assumptions about what they're doing at the pedals - and a lot of those assumptions are wrong. Challenging those assumptions will result in one of three outcomes. The common one is anger and outrage - how can anyone not know how to pedal a bike? I then often get told how long they've been riding... The less common outcome is to entertain this idea that learning how to pedal might just be a good idea. The third outcome is that I'm wrong, so I built a test rig...

https://drive.google.com/file/d/0BzP...ew?usp=sharing

You mention dead spots...

I started riding the trainer this winter.. first time ever, and it's been an awkward thing for me.. but one thing I notice is that it's very easy for me to get little voids in my pedal stroke that go clackclack softly when the chain goes tight again. I've never felt anything like it in my outside on-the-road pedal stroke..... but then, a couple days ago, I had a long-story-short wheel catastrophe that had me running a 12-25 cassette on a TT, when I'm already not a TTers and used to running an 11-28 for my preferred hills... and I found that the significantly more gradual gearing mixed with TT mashing was also inducing these same clackclack pedal voids I experienced recently on the trainer.

What's up with that? Suddenly I feel like I need to start studying pedal stroke efficiency

[Uncle Jam's Army]

Originally Posted by Ti Designs

Having done a bit of research myself, the one conclusion I keep returning to is that people make a lot of assumptions about what they're doing at the pedals - and a lot of those assumptions are wrong. Challenging those assumptions will result in one of three outcomes. The common one is anger and outrage - how can anyone not know how to pedal a bike? I then often get told how long they've been riding... The less common outcome is to entertain this idea that learning how to pedal might just be a good idea. The third outcome is that I'm wrong, so I built a test rig...

https://drive.google.com/file/d/0BzP...ew?usp=sharing

Ed, your posts and videos have helped me think long and hard about my pedal stroke and how to achieve efficiency with it. I still haven't figured it all out, but I enjoy the process of trying to do so. Many thanks.

[1centaur]

I like that rig, TiD.

One of the interesting things about unweighting a leg vs. lifting it is that the more unweighted the leg the easier it is for the power leg to push the pedal up into the unweighted leg. At some point unweighting becomes pulling just so the unweighted leg can stay ahead of the chasing power leg.

This is not to say that the lifting muscles have a lot of power, but ultimately I think those puny muscles are better trained to pull a little than just to unweight.

Single leg drills miss this point because there is no power leg chasing the pulling leg, but at the same time they don't just unweight because then the stroke would not continue.

[leftyfreak]

Enough comments about the rig. Nice hat! I can't believe I've never seen it before.

So, when do I get a turn on that rig/torture device?

[Ti Designs]

Originally Posted by The B

I started riding the trainer this winter.. first time ever, and it's been an awkward thing for me.. but one thing I notice is that it's very easy for me to get little voids in my pedal stroke that go clackclack softly when the chain goes tight again.

Do you know what detonation or knock is when talking about a car engine? It's ignition (well, really thermal expansion) of the fuel mixture before the piston reaches top dead center. It's a serious problem because the expansion while the piston is still going up subtracts energy from the system, and the pressure at the cylinder head spikes. On a bike, starting to push down before TDC (12:00) is very much like that. It slows the crank going over the top and increases the tension of the patellar tendon. The deceleration causes the chain to lose tension, getting over the top regains tension, that's what you hear. I'm doing a video series about destructive forces in sport for a local hospital that covers this.

[Mark McM]

Originally Posted by Ti Designs

Do you know what detonation or knock is when talking about a car engine? It's ignition (well, really thermal expansion) of the fuel mixture before the piston reaches top dead center.

Well, technically, combustion/gas expansion always starts before TDC - knock happens when parts of the fuel/air mixture explodes/expands ahead of the normal combustion pressure front.

But I get your point - muscle contractions that happen too soon (or continue too late) in the pedal stroke are detrimental to power and efficiency.

[Mark McM]

Originally Posted by 1centaur

One of the interesting things about unweighting a leg vs. lifting it is that the more unweighted the leg the easier it is for the power leg to push the pedal up into the unweighted leg. At some point unweighting becomes pulling just so the unweighted leg can stay ahead of the chasing power leg.

This is not to say that the lifting muscles have a lot of power, but ultimately I think those puny muscles are better trained to pull a little than just to unweight.

For short duration efforts, this is definitely true. But aerobic efforts are limited more by the ability to circulate blood/oxygen to the muscles (and carry away waste products) than the by the total amount of muscle available, so trying to pull up too much can be a matter of robbing Peter to pay Paul. Any blood/oxygen used trying to pull up is stolen from the larger and more effective muscles pushing down.