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Old 01-17-2021, 12:39 PM
Ti Designs's Avatar
Ti Designs Ti Designs is offline
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Location: Arlington MA
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Originally Posted by m_sasso View Post
No, it is not a rule of thumb it is a law of physics, the more open the joint angle the greater amount of torque that can be generated across the joint.
There's a sweeping generalization about physics and biomechanics that just doesn't work. The joint is the fulcrum, the attachment point(s) of the connective tissue determines the length of the lever arm, the muscle is far from a linear motor both in terms of force produced and cost...

A better understanding of how the motor works would be the right first step. We're talking hip angle, we're talking glutes - nothing beyond the femur counts at this stage. For isolation I would suggest using an incline sled with an adjustable back. Set up the sled with a camera at your side so it's a rotation of your position on the bike. You can use adjustable weight stands to set your starting hip angle, then it's just a matter of finding your overload weight at various hip angles. If you're like most people you'll find your maximum torque is well before 90 degrees.

One word of warning: Muscles have two limits, a strength limit and a tensile limit. Most riders I've worked with find their strength limit > their tensile limit. So, if you can't walk up stairs the next day it means you've exceeded the tensile limit of the muscle.

Once you have characterized the muscle you can intelligently work on your position. Keep in mind that there are two large muscle groups which produce 99% of your power. The glutes produce lots of torque, but are limited in leg speed. It's a wide muscle with a long distance from fulcrum to attachment point. The quad is a much thinner muscle with a very short distance from fulcrum to attachment point - it's designed like a kick drum pedal. If you're looking for leg speed the range of angle at the knee is what you should be looking at. You can characterize the quad/knee with a leg extension machine the same way.
If the pedals are turning it's all good.
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Old 05-04-2021, 06:19 AM
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weisan weisan is offline
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There's so much to unpack here.
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Old 05-04-2021, 06:53 AM
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oldpotatoe oldpotatoe is offline
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Originally Posted by weisan View Post
There's so much to unpack here.
In this 7 month old 'zombie' tread...
Sounds like Ti designs above in January summed it up pretty well..
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