Increased squat jump height is associated with faster landmine punch throw peak velocity

As punch speed and punch force are important for boxing performance, the landmine punch throw is a speed-strength exercise that is used in training due to its similarity to lead- and rear-hand boxing punches. This exercise is a whole-body ballistic movement whereby an athlete throws a barbell that is fixed to a 3-diminsional moveable attachment on the floor at one end. This exercise is performed with a linear upward push (approximately a 40-60° upward), resulting in affected by force production from the lower body arc about the axis on the floor attachment. As such, this exercise is largely affected by the lower body, trunk rotation, and the upper body. Since strength and conditioning programs include exercises focused on trunk rotation and upper and lower body strength and power development, it would be useful to determine how much each of those factors contributes to punch velocity. PURPOSE: The purpose of this study was to determine the extent of which lower body squat jump performance contributes to the peak velocity of a punch-specific exercise like the landmine punch throw. METHODS: 14 healthy boxers (24.1  4.3 y, 72.6  10.1 kg, 176.9  8.3 cm) performed a single testing session. Although all subjects routinely used the landmine punch throw exercise during training, they were all familiarized with the testing procedures, which was followed by standardized mobilization and dynamic warm-up exercises. The protocol included 3 individual squat jumps. Then, subjects performed three repetitions of three different landmine punch throw variations (seated without trunk rotation [LPwo], seated with trunk rotation [LPw], and standing with trunk rotation and the use of the legs [LP]); each with three different loads (barbell, barbell +2.5 kg, barbell +5 kg); with the rear hand (RH) and lead hand (LH); all in randomized order with 3 min of inter-set rest. Each test was performed with maximal effort. Squat jump height (SJH) was measured with an Optojump Photocell system. A GymAware power tool was attached to the barbell to assess peak velocity (PV) during the landmine punch throw variations. To determine how SJH can affect PV, we modelled PV as a function of landmine punch throw variation, load, and hand in interaction with participant’s SJH. RESULTS: The effect of SJH on PV was significantly greater in LP than in LPw and LPwo (p<0.001). For example, every increase 1 cm increase in SJH increased landmine punch throw PV by 0.036 m/s (β = 0.036 [SE 0.012], p=0.006) for the barbell-only LP with the RH. However, this finding was not significant in LPw (p = 0.124) or LPwo (p = 0.128). Similar results were found for landmine punch throw with heavier loads and with the LH. CONCLUSION: The study found that SJH affected landmine punch throw PV when performed with the whole body (LP), but not with the other variations (LPw or LPwo). These results indicate that increasing lower leg force production can transfer to increased velocity of the landmine punch throw. PRACTICAL APPLICATION: Considering the movement specificity of the landmine punch throw (i.e. total body movement), coaches should aim to improve the lower body strength and rate of force development to improve punch speed by explosive exercises to improve punch speed.