Half-squat or jump squat training under optimum power load conditions to counteract power and speed decrements in Brazilian elite soccer players during the preseason

Abstract

The purpose of this study was to test which specific type of exercise (i.e., jump squat (JS) or half-squat (HS)) is more effective at maintaining speed and power abilities throughout a preseason in soccer players. Twenty-three male soccer players were randomly allocated into two groups: JS and HS. The mean propulsive power, vertical jumping ability, and sprinting performance were evaluated before and after 4 weeks of a preseason period. The optimum power loads for the JS and HS exercises were assessed and were used as load-references. The soccer players performed 10 power oriented training sessions in total. Both JS and HS maintained power in JS and speed abilities (P > 0.05, for main effects and interaction effect) as indicated by ANCOVA. Both groups demonstrated reduced power during HS (ES = -0.76 vs. -0.78, for JS and HS, respectively); both groups improved acceleration (ACC) from 5 to 10 m (ES = 0.52). JS was more effective at reducing the ACC decrements over 0-5 m (ES = -0.38 vs. -0.58, for JS and HS, respectively). The HS group increased squat jump height (ES = 0.76 vs. 0.11, for HS and JS, respectively). In summary, JS is more effective in reducing the ACC capacity over very short sprints while HS is more effective in improving squat jump performance. Both strategies improve ACC over longer distances. New training strategies should be implemented/developed to avoid concurrent training effects between power and endurance adaptations during professional soccer preseasons.

Jump-Squat and Half-Squat Exercises: Selective Influences on Speed-Power Performance of Elite Rugby Sevens Players

“…For instance, a recent study exploring the particular effects of loaded jump squats and half squats in elite soccer players revealed that both exercises are capable of reducing the decrements in speed-power capacities that commonly occur throughout professional soccer preseasons[13]. Also, Hori et al [14] demonstrated that standard weighted jump squats may cause larger adaptations in the force applied at high velocities (peak torque during isokinetic knee flexion at 300° .…”

Mechanical Differences between Barbell and Body Optimum Power Loads in the Jump Squat Exercise

“…Another common way of testing the “optimum power zone” is to assess the power production directly from the barbell, using a linear position transducer (LPT) (Loturco et al, 2015d; Talpey et al, 2014). Different from the body-power measurements (traditionally performed using force plates) (Soriano et al, 2015), the bar-power production is always optimized at a moderate range of loads (Loturco et al, 2015d; Loturco et al, 2013).…”

“…Different from the body-power measurements (traditionally performed using force plates) (Soriano et al, 2015), the bar-power production is always optimized at a moderate range of loads (Loturco et al, 2015d; Loturco et al, 2013). For instance, Baker et al (2001) revealed that loads in the range of circa 48–63% of 1-RM seemed to be effective at maximizing bar-power during the JS in power-trained subjects.…”

“…Recently, some authors have suggested the use of mean propulsive power (MPP) to determine the optimum power zone in strength-power exercises (Loturco et al, 2015d; Sanchez-Medina et al, 2010). Accordingly, Sanchez-Medina et al (2010) demonstrated that the mechanical values collected during the propulsive phase of a lift better reflected the differences in neuromuscular performance between two given individuals.…”

“…In fact, JS MPP has been shown to be highly correlated with specific performance in athletes from distinct sports (Loturco et al, 2014, 2015a, 2016a). Additionally, it has been shown that training at the optimum load produces greater performance improvements than traditional strength training and reduces the speed-power decrements that usually occur during soccer preseasons (Loturco et al, 2015d, 2016b). …”