Why work on pedal stroke?

 

There’s an old saying, “as easy as riding a bike”.  That would imply that everyone is born with that skill set. How is that possible? You spent the first year of your life learning how to walk, with a number of failures along the way, but you were born knowing how to pedal a bike?  The truth is the bike eliminates the failure states – you can’t make the pedals go in any path other than the circle determined by the cranks and bottom bracket.  Go ahead and try, get on your bike, clip into your pedals, make the pedal go in anything other than that circle. If you can, please make a video, ’cause I want to see it.  The fact is you don’t really push the pedals in the right direction, but if your efficiency is greater than zero, the pedals will go around the right way.

The facts:

  1. The human body doesn’t produce much power – see cyclist vs. toaster. Having an inefficient pedal stroke wastes power.
  2. Your primary skill set for locomotion is walking, which is based on the hip being centered over the stride. That’s not how you ride a bike – you’ve been doing it wrong.
  3. Your feedback is based on what is familiar to you, not what’s correct. Without active changes you will always return to the skill set you know the best. That’s walking not pedaling.

Testing:

This is the display for a Pioneer power meter. The two graphs show left and right pedal stroke, with force vectors shown every 30 degrees around the circle. It is the best testing method there is for seeing how efficient your pedal stroke is, and where it needs work.

This is the scan of a cyclist who assumes his pedal stroke is pretty good. By pretty good I mean he’s only wasting 32% of his energy. He’s producing over 400 watts, so there are some good strong vectors right at 3:00, but his timing is way off and he’s pushing down at the bottom of the pedal stroke, which is a waste of power.

Building a good pedal stroke

The pedal stroke program is based on two muscles – glutes and quads. They happen to be the two largest muscles in the body. Glutes extend the leg from the hip, they use your upper body weight for leverage and can only push down.

To make life simple, we’re going to say the pedal is going down from 1:30 to 4:30 (45 degrees up to 45 degrees down), that’s the only place the glutes are used.

Quads extend the lower leg from the knee, they can only push the pedal forward.

We’re going to say the pedal is going forward from 11:00 to 2:00. so that’s the only place the quads are used.

The end result

If you learn how to just use your quads from 11:00 to 2:00 and your glutes from 1:30 to 4:30, you’ll be around 25% more efficient than the average rider – that’s more of a gain than you could ever expect from the hardest training program. The truth is better than that. By separating out the muscle groups you’ll learn that glutes can generate huge amounts of torque, so they’re well suited to climbing. Quads generate leg speed, they’re best used for flat speed and accelerating. They are two separate muscle groups, your can burn one and the other one still works just fine.

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