Effects of 8-Week In-Season Contrast Strength Training Program on Measures of Athletic Performance and Lower-Limb Asymmetry in Male Youth Volleyball Players

Abstract

Strength training using high and lower load such as contrast training (CST) seems to be beneficial as it addresses larger adaptive reserves in youth athletes. Therefore, the aim of this study was to investigate the effects of CST on dynamic balance (composite score during dynamic balance test (CS-YBT)), one repetition maximum lower-limb back squat (1RM), jumping performance (single-leg hop (SLH) or countermovement jump height (CMJ)), lower-limb asymmetry (predicted from the single-leg jump performance between two legs [ILA]) in elite youth male volleyball players. Thirty-one male youth volleyball players aged 14 years were randomly assigned to a CST group (n = 16) or a control group (n = 15). The tests were performed before and after 8 weeks of training. Significant group × time interactions was observed for CS-YBT [p < 0.001, ηp2 = 0.70], 1RM [p < 0.001, ηp2 = 0.95], SLH with right and left leg [p < 0.001, ηp2 = 0.69 and 0.51], CMJ [p < 0.001, ηp2 = 0.47]), whilst it was not notable in ILA [p < 0.294]. Post hoc tests showed that CST group demonstrated greater improvement in all of the dependent variables from medium to large effect size (for all p < 0.001). As a result, 8 weeks of CST twice a week can be an effective and efficient training along with volleyball training to improve skill-related fitness measures, except for lower-limb asymmetry in young volleyball players.

Horizontal jump asymmetries are associated with reduced range of motion and vertical jump performance in female soccer players

“…This study also establishes a relationship between ankle dorsiflexion and dynamic balance in athletes. This aspect supports the systematic review carried out by Mesfar et al [ 51 ], which indicates that there may be a specific association between the asymmetries of this dynamic balance and jumping performance and, on the other hand, the range of movement of the ankle and the COD tests in that involving a 180° turn. Other studies have also confirmed this, which have found significant relationships between ankle ROM and improved dynamic balance or lower body motor skills [ 52 , 53 ].…”

Long-Term Changes in Vertical Jump, H:Q Ratio and Interlimb Asymmetries in Young Female Volleyball Athletes

“…These results are in agreement with previous studies that found an increase in asymmetry even after a long-term training program [ 63 , 64 , 65 ]. However, contralateral asymmetry is a controversial topic in the literature because some studies have described important changes in interlimb asymmetries in young athletes after a specific training program [ 64 , 66 ], while others have found any effect [ 67 , 68 ]. The main reason for the discrepancies found among the studies seems to be the variable chosen to assess contralateral asymmetry because many contralateral neuromuscular asymmetries found throughout a season show different magnitudes and directions of change.…”

The Influence of Plyometrics and Weight Training Exercises on Limbs Muscle Power in View of Limbs Muscle Endurance in Volleyball Players Aged 16-18 Years

“…muscle power can be increased by explosive movements and jumping without a prefix such as in basketball and volleyball (Wang et al, 2022). Athletes need to develop leg muscle power by performing speed and acceleration movements then with specific movements in sports (Mesfar et al, 2022). Therefore, coaches certainly need to look at and consider the needs of the sport when training (Schofield et al, 2022).…”