si' in teoria gli angoli restano uguali ma in pratica vengono riscontrati reazioni diverse.
a seguire una delle spiegazioni , prendendo chiaramente ispirazione da uno dei posizionatori americani piu' noti che regola l'avanzamento in base alla stabilita' del bacino prodotta dalla spinta sui pedali, senza mani sul manubrio.
If we look at a cyclist from the side, their hips sit behind their feet during the power phase of the pedal stroke. And at all times, the hips are above the feet, because our saddle is above the cranks and pedals -- pretty basic, right?When we push on the pedals during the power phase of our stroke the pedals are pushing back. Newton’s Second Law of Motion is the one that has the “equal and opposite reaction” clause in it, so not only are you acting on your pedal, your pedal is acting on you as well.Because the pedal is below your hips/pelvis, when you push down on it, it’s pushing back up on you (and your pelvis). This is great because it provides, among other things, a brief period of unloading of pressure on the saddle -- it literally saves your butt during rides. This is why one of the largest segments of riders plagued with severe saddle issues has partially to do with their lower power output relative to their body weight. If your power to weight ratio is poor you’re not going to be un weighting the saddle much.Because the pedals are in front of your hips/pelvis during the power phase, when you push down on the pedal, the pedal is also pushing you backwards on the bike. This exerts an aft or posterior force on the pelvis which provides stability by keeping it securely in place on the saddle instead of sliding forward. When the hips stay backwards on the saddle, the hip extensors have a solid platform to push from. When the hips slide or roll forward during the pedal stroke (because the seat/pelvis is not far back enough behind the pedals/feet), the fact that the pelvis is moving keeps the hip extensors from working at their full level.When the hip extensors don’t work as much, or perhaps they’re delayed, it requires the quadriceps to work more and this extra work and force is passing through the quad and patellar tendon.
Knee Pain Bike Fit Basics -- JH — Bike Fit Adviser
The Simple Rule for knee pain The two main areas -- the front and back of the knee -- do have some simple correlations that many have heard about. Namely if the pain is in the front of the knee (quad tendon/patellar tendon/patella) then the saddle is too low, and that if the pain is is at
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