Optimal Force-Velocity Profile in Ballistic Movements-Altius: Citius or Fortius?

SAMOZINO, P., E. REJC, P. E. DI PRAMPERO, A. BELLI, and J.-B. MORIN. Optimal Force-Velocity Profile in Ballistic Movements-Altius: Citius or Fortius? Med. Sci. Sports Exerc., Vol. 44, No. 2, pp. 313-322, 2012. Purpose: The study's purpose was to determine the respective influences of the maximal power ((P) over bar (max)) and the force-velocity (F-v) mechanical profile of the lower limb neuromuscular system on performance in ballistic movements. Methods: A theoretical integrative approach was proposed to express ballistic performance as a mathematical function of (P) over bar (max) and F-v profile. This equation was (i) validated from experimental data obtained on 14 subjects during lower limb ballistic inclined push-offs and (ii) simulated to quantify the respective influence of (P) over bar (max) and F-v profile on performance. Results: The bias between performances predicted and obtained from experimental measurements was 4%-7%, confirming the validity of the proposed theoretical approach. Simulations showed that ballistic performance was mostly influenced not only by (P) over bar (max) but also by the balance between force and velocity capabilities as described by the F-v profile. For each individual, there is an optimal F-v profile that maximizes performance, whereas unfavorable F-v balances lead to differences in performance up to 30% for a given (P) over bar (max). This optimal F-v profile, which can be accurately determined, depends on some individual characteristics (limb extension range, (P) over bar (max)) and on the afterload involved in the movement (inertia, inclination). The lower the afterload, the more the optimal F-v profile is oriented toward velocity capabilities and the greater the limitation of performance imposed by the maximal velocity of lower limb extension. Conclusions: High ballistic performances are determined by both maximization of the power output capabilities and optimization of the F-v mechanical profile of the lower limb neuromuscular system.