Patella tendon pain help.

[Calf]

true but there isn't that much power or force for the muscle to work against as the leg straightens on the down stroke of the crank rotation.

when I cycle the muscles doing the work are definitly the outer side which is why alot of cyclist get ITB issues
I know when I'm in the gym on the extension machine it is the VMO doing all the work as I can see it.

My theory revolves around the fact that the main cause of an incorrect tracking knee cap seems to be a weak VMO or an imbalance from one side of the thigh to the other.
So if your going to do lots of exercises which involve strengthening the thigh as a whole your not going to address the imbalance.
However I've yet to be rid of this so its prob all balls

[Calf]

ok prob getting out of my depth here but if certain muscles are activated during a certain portion of the leg movement if your leg is restricted to a certain range of movement ie in cycling then the other muscles are not going to strengthen as much.
Also if some parts of your thigh muscle are one side of you knee and some on the other side then if the knee cap is to remain running/moving as it should there needs to be a balance. If it was impossible to have an imbalance as you say then how anyone get knee injuries of this type?

[Calf]

quite enjoying this.
Ok can see where your coming and perhaps I'm looking at this from an engineering point of view too much.

However if you have a rock and attached to the rock are 3 ropes. Each attached at a different point on the rock at the end of each rope is a person, now the peoples job is to move the rock (its not a very exciting life but at least they get outside), however they cannot all stand in a line like a tug of war because of the way the ropes are attached. So one stands in the middle and the other two either side slightly off centre.
When they are all working well together they all apply a similar force on the rope and rock moves in a straight line. However when one of em has been drinking on a school night and isn't feeling so good he can't quite put the same force in as the others. This happens to be one of the blokes on the side. So when they all pull together the forces aren't going to be balanced and the rock will be pulled to the stronger side.