The normal stretching advice is to do passive/yoga type stretching, avoid dynamic (moving, like Scott's) and only do pnf(contract and release) under supervision.
That approach claims to be the safest. No data to support it, though.
It turns out that dynamic stretching boosts strength and athleticism and passive stretching can actually reduce strength by up to 30%. Those are just short term effects, but still something to consider for the athlete.
Passive/yoga stretching may be so weakening as it is arguably the most relaxing. Just as a relaxing hot bath saps strength, so does yoga.
The new approach amongst enlightened trainers seems to be to do dynamic before activity and passive afterwards and do pnf 3x a week. (pnf is the most powerful way to actually lengthen the muscles, then passive, then dynamic).
There are lots of different opinions out there.
Here are a couple thoughts I found:
Static methods produce far fewer instances of muscle soreness, injury and damage to connective tissues than dynamic or ballistic methods. Static methods are simple to carry out and may be conducted virtually anywhere. For maximum gains in flexibility in the shortest possible time PNF technique is the most appropriate. Dynamic - slowed controlled movements through the full range of the motion - will reduce muscle stiffness. Where the technique requires ballistic movement then ballistic stretches should be employed.
On the other hand, dynamic and PNF techniques pre-weight training facilitate the potentiation of the nervous system, thereby increasing strength and muscle pump. This increases stability and stiffness once again.
Catanzaro: Dynamic stretching before weight training will temporarily increase strength. This form of stretching is used to rev up the nervous system so I can’t completely agree with the original statement that stretching before weight training will make you weaker.
As mentioned above, PNF stretching (particularly the CRAC method) will liberate the greatest ROM. Let me remind you that PNF or dynamic stretching is useful for warm-ups since the lingering discharge (facilitation) from the contraction phase of a PNF or dynamic stretch counters the effects of any reduced stiffness.
Acute static stretching, on the other hand, can decrease strength of the stretched muscles by as much as 5 to 30%.
Thanks for any thoughts!