The relationship between jumping, acceleration, change of direction, and relative strength for deadlift and back squat

BACKGROUND: Deadlift (DL) and back squat (BSQ) are considered different exercises because of their kinematic and kinetic characteristics. However, there are similarities, such as joint movement and the maximal muscle strength generated. Although there are differences and similarities, it is unclear which is more related to athletic performance. OBJECTIVE: This study aimed to determine the relationship between DL and jump, acceleration, and change of direction and compare whether DL or BSQ differ in their relationship to jumping, acceleration, and change of direction. METHODS: Eighty male volleyball players (age: 19.6 ± 0.9 years, height: 179.2 ± 6.7 cm, mass: 71.9 ± 9.4 kg) volunteered to participate in this study. Countermovement jump (CMJ), 10-m sprint, and 1–5 repetition maximum (1–5 RM) BSQ were measured on day 1. The T-test and 1–5 RM DL were measured on day 2. RESULTS: DL had a significant and moderate relationship with all parameters of CMJ (r= 0.328, p< 0.01), 10-m sprint (r=-0.471, p< 0.01), and T-test (r=-0.441, p< 0.01). BSQ showed a significant and moderate relationship with the 10-m sprint (r=-0.489, p< 0.01) and T-test (r=-0.356, p< 0.01), but a significant and weak relationship only with CMJ (r=- 0.289, p< 0.01). In addition, no significant differences were found in the comparison of correlation coefficients (p> 0.05). CONCLUSIONS: Deadlift may be introduced as an alternative exercise to BSQ when there are limitations in the training environment, such as the lack of a squat rack to safely perform BSQ or home confinement due to external factors like pandemics.