Tim W. Dorn, Anthony G. Schacheand Marcus G. Pandy Department of Mechanical Engineering, University of Melbourne, Victoria 3010, Australia
The Journal of Experimental Biology 215, 1944-1956 © 2012. Published by The Company of Biologists Ltd
Many of the other articles reviewed on this website examine the potential of various training techniques to improve acceleration, top speed, or agility. This article however deviates from the norm. Dorn and his associates use computer modelling of the human body to calculate the contributions of the main muscle groups at various running speeds. Computer modelling is the only way to calculate the contributions of muscles to a given task at this time. (Electromyography can provide information regarding the on/off patterns of muscles and even the strength of muscle contraction in an isometric situation through integrating of the waveform. But this relationship breaks down during dynamic activities such as running).
The results of their study pinpoint the muscles which should be targeted in an effective sprint training program. Up to 7m/sec, the athletes used the soleus and gastrocnemius (ankle plantar flexors) to increase stride length, thereby increasing running speed. Above 7m/sec the ankle plantar flexors could not contract fast enough to generated greater amounts of force, so a different strategy was required. The athletes switched to increased stride frequency and the muscles used to achieve this were the hamstrings gluteus maximus and the iliopsoas (Iliacus and psoas). Interestingly, Rectus femoris, while also being a potential hip flexor, was not a major contributor during the swing phase.
Obviously, most training programs would place significant emphasis of the gluteus maximus and the hamstrings, but the iliopsoas may be neglected. These muscles will be used during any hip flexion activity such as leg raises and sit-ups but we would suggest bench sit-ups with the knees bent to 90 degrees or more. We would also suggest weighted hip flexion, with an emphasis on high knees. Of course this is general information only and should not be performed without prior medical clearance.
Our thanks go out to Tim Dorn and his team for this informative piece of research.