The Biomechanical Analysis of Sprinters
Ralph Mann
Track Technique
94: 3000-3003, 1986
…We found leg action to be significantly related to the critical variables of horizontal velocity, stride rate, and support time. In relating the arms to the same variables we did not find a single thing that was significant. Neither the arm velocity, arm position, or anything that the arms were doing related to any of these variables. Thus, it appears that the arm action is not significant in increasing stride rate or horizontal velocity, or in decreasing support time as a performer improves from a good to elite sprinter. Some argue that you have to move the arms faster to improve sprint speed; but perhaps this is not the case. When sprinting, the arms actually hesitate at the dead end positions; and what we are finding is that the elite athlete is not moving the arms faster, but simply not hesitating as long at the dead-end positions.
The real key to sprint improvement lies on the leg action and, more specifically, leg action just prior and during ground contact. We have found that the best sprinters minimize the upper leg range of motion during ground contact, as well as producing greater upper leg speed. Thus, the ground contact time is decreased by generating high leg speed prior to ground contact, touching down closer to the body center of gravity, maintaining the leg speed during ground contact, and getting airborne as quickly as possible. The only surprise in these findings was the lack of leg extension at takeoff. In the possible tradeoff of greater leg extension to increase speed versus abbreviated leg extension to decrease ground contact time, it appears that the latter produces better results.
If these findings by Ralph Mann are to be correct, are sprinters wasting there time doing upper-body resistance training i.e Bench Press, Bicep Curls etc and instead should focus all there attention to the Lower-body???..
I do to some extent agree with Ralph and from past experience I realised when I just conditioned my Lower-body, my 30 metre times got better (decreased). When I started working the Upperbody I just felt that that it over-rode my Lower body and some what took over… I felt more power but also felt my acceleration was not as good.
Any comments???..