Squat Jump

The Squat Jump (SJ) test is typically used to measure an athlete’s explosive lower-body power (i.e. speed-strength ability) [2, 3]. It is also less commonly used to in conjunction with a CMJ to identify an athlete’s reactive strength capacities (read about reactive strength capacity HERE) during slow stretch-shortening cycle/low stretch loads [2]. This offers novel information as it can be compared with their performance during fast stretch-shortening cycle/high stretch load reactive strength tests such as the Incremental Drop Jump test [2].

There are two common variations of the SJ test:

1. Static SJ test

2. Dynamic SJ test

The static SJ test requires the athlete to ‘pause’ in a flexed semi-squat position for several seconds before initiating the upward/concentric phase and jump. The dynamic SJ test, on the other hand, allows the athlete to descend and ascend through the countermovement in one continuous and rapid motion without any stop or pause.

Strength and conditioning coaches will often measure an athlete’s SJ capabilities using various loads in order to identify their power production abilities.  For example, a coach may ask the athlete to perform a series of SJs – whether that be static or dynamic – using loads such as 20, 40, and 60% of the athlete’s back squat 1-repetition maximum (1RM). The athlete’s back squat 1RM is typically used to determine the loads for the SJ purely because of its biomechanical similarities and relationship with back squat strength [4]. Using various loads, the coach is able to plot the athlete’s performance on a graph, known as a ‘power-load curve’, and identify at which load the athlete expressed their peak power output (Figure 1).