Ok, when your knee raises and the lower leg kicks out…
A) Should we ALLOW extended kick out?
B) should we minimize kick out, after foot has allready extended pass knee?
Arguments for either as far as I can see;
When the leg kicks out nice and relaxed, it apparently allows quads to spend more time shooting out the leg or something, which enables hams etc… to throw down the leg more powerfully. (That was possibly the crappest sentance I have printed on this website.)
V
When the stride opens up with relaxed kick out, it is harder for hammies to exert force, the longer the muscle and further way the ankle from hip joint, harder for hammies to whip back lower leg with as much force.(that’s the theory of muscle length & contraction force according to some )
So what are we to do?
I don’t force anything in a sprint, but it is easy to work on things in specialised power-speed drills etc…
Just by being more relaxed with the hammies the lower leg will kick out further, isn’t sprinting about relaxation? But how far or long do we let the relaxation go on for before the hammies HAVE to whip back lower leg?
What do we want to achieve?
I don’t want my stride to become short and choppy, but I don’t want to lose the power either.
Carl Lewis and Ben Johnson had a kick out for sure, where-as Carls teammate Leroy Burrell did not allow the lower leg to whip out as far.
Niether did Bob Hayes.
I should have been clearer on this.
Certain power/speed drills are good, others are not…
One drill is a step over drill where you have 2 options.
After the step over you can either;
A) LET the lower leg whip out via relaxation.
B) Not let the lower leg whip out as far by forcing the thigh down as soon as the foot has moved to under knee of same raised leg.(when knee is way out in front of hips ofcourse.)
B feels far more powerfull (power builder) than A, where-as A is obviously more relaxed.
Which way should this power speed drill be done?
Any of the big guns want to chip in?
i would say not to encourage the “lower leg whip out” because that causes over-striding. I’ve heard many other people say this but “its not where your feet go, its where your belly button goes” Plus the “lower leg whip out” puts athletes at a higher risk for hamstring injuries.
Thankyou for the response. That is putting some more light on it for me. 
The lower leg does tend to move out when the leg is relaxed but if the hip is high enough, it is close to BDC by foot strike. It shouldn’t be forced out nor should it be restricted.
after the knee reaches optimal vertical position, the lower leg “kicks out” due to a transfer of angular forces (momentum), as I understand it. The natural “kick out” then becomes part of the recoil mechanism (for want of a better description) which necessarily aids in creating the reverse thrust at ground contact which enables you to move forwards. Don’t mess with nature.
charlie, would extending the lower leg in front of you not constitute “reaching” thus causing overstriding.
If you deliberately reach, your hip must drop. Conversely, if your hip is up as high as it should be you are not reaching.
So, would it be advantageous to deliberately try to run with your hips higher, or is that just a result of running fast?
More the result of relative power, relaxation, and good posture.