A simple method for measuring lower limb force, velocity and power capabilities during jumping

Abstract

Lower limb ballistic movement performance (jump, sprint start, change of direction) is considered to be a key factor in many sport activities and depends directly on the mechanical capabilities of the neuromuscular system. This chapter presents the force-velocity (F-v) and power-velocity (P-v) relationships, and their associated variables of interest, as an interesting tool to evaluate the different lower limb muscle mechanical capabilities during ballistic push-off: maximal power and F-v profile. In this chapter, we will present the different laboratory and field methods to directly or indirectly assess these muscle properties, as well as their respective limits. We will also present an accurate and reliable simple field method to determine these muscle capabilities with a precision similar to that obtained with specific laboratory ergometers, while being convenient for field use because the computations only require loaded jumps (accurately standardized and performed) and three parameters rather easily measurable out of laboratory: body mass, jump height and push-off distance. The use of this simple method as routine test gives interesting information to coaches or physiotherapists: individual maximal power output and F-v profile. Validation studies, practical testing considerations and limits of this simple method will be presented. This method makes possible the follow-up of athlete muscle capabilities during a season or over several years, but also the comparison between athletes, which can help to optimize training and individualize loads and exercise modalities in strength training.