Lead leg extention and the Asmi

this was copyed from a asmi study that had to do with fast pitchers vs slow pitch delivery’s It say’s that… read the bold I find that interesting.


In the study by Matsuo and others, pitchers with higher ball velocity were compared with pitchers with lower ball velocity. Four significant differences were found between these two groups. Compared to the low ball velocity group, the higher ball velocity pitchers demonstrated less lead knee flexion velocity after front foot contact and greater lead knee extension velocity at the time of ball release. Extending the lead knee in this manner may provide stabilization allowing better energy transfer from the trunk to the throwing arm, and could be a critical factor in pitch velocity. Maximum shoulder external rotation and forward trunk tilt at ball release were also greater in the higher velocity group. Greater shoulder external rotation causes a stretch of the internal rotators allowing energy to be stored in these muscles, and creating greater internal rotation during the arm acceleration phase.

what you think?
Should all pitcher extend there front leg or just brace it?

First, RIstar, unless you want to start another thread like “that other one”, I would refrain from starting your question with “Should all pitchers…”. Avoid those terms of absolutes.

Regarding the study, I fail to understand the value in measuring front knee flexion velocity. What does that signify? When does front knee flexion start? Does it differ depending on whether the pitcher strides with the leg straight or bent to start with? I don’t get it.

Now, measuring the velocity of front knee extension after foot plant could be an indication of momentum but that would seem to depend on other factors as well (e.g. front leg strength, posture, etc.). It’s not clear that this measurement by itself says much.

So, I can’t really conclude much of anything from the text you quoted. Do you have a link to the entire study?

One other thing… I’m not sure bracing is an alternative to extension. Pitchers who extend without bracing first, simply go into trunk flexion sooner. This has bearing on the posture at release. I prefer the trunk to be upright and for the shoulders to rotate around an upright spine. Trunk flexion waits until the last moment right before the arm snaps forward.

Immature but I have to say it :


Well if I understand the article right, it seems to be saying the higher velocity throwers bend less with their lead leg than the lower velocity guys. And if thats true, what I get from it is that the higher velocity guys straighten their leg more, which man possibly placing more of the strain of throwing back into their arm. I also believe it gives a greater potential for velocity, because the stiffer leg gives more room for the hips to rotate.

What the front leg does definitely has bearing on hip rotation. But do you really think that ALL hard throwers straighten their leg more? Actually, “more” is a very vague term in this context. The study referred to velocity of leg extension so does “more” mean “faster”?

It seems to me that a pitcher who starts his leg extension soone will extend slower. A pitcher who starts his extension later will extend faster. I’m guessing the reason a pitcher would start his extension sooner is because he lacks the strength to flex deeper and then extend. In other words, he’s matching what his strength will support with the momentum he generates. So, I guess, pitchers who generate more momentum and have the strength to support that can possibly throw harder. But I’ve said that all along - it’s not just about moving faster but also having the functional strength and flexibility to maintain good posture and balance. Is this what I’m supposed to be taking from this study? I’m still not sure.

If a clip of Sandy Koufax is available it would be interesting to hear folks describe his lead leg action.