PURPOSE:To examine the relationships between muscle architecture and countermovement jump height, peak power, and maximal strength in collegiate volleyball players and to generate hypotheses to direct future research.
METHODS:Fourteen female volleyball players (20 ± 1.3y, 176.3 ± 6.6cm, 70.1 ± 8.4 kg) were recruited as part of an ongoing athlete monitoring program. Athletes were tested on measures of vastus lateralis (VL) and lateral gastrocnemius (LG) muscle thickness (MT), pennation angle (PA), and fascicle length (FL) using ultrasonography; countermovement jump height (CMJH, n = 14) and peak power allometrically scaled (CMJPPa, n = 14); and isometric peak force allometrically scaled (IPFa, n = 12). Data were screened for outliers using box plots and normality was determined using a Shapiro-Wilk test. Intraclass correlation coefficients (ICCs) for dependent variables ranged from r=0.88 to 0.99. Pearson’s product moment zero-order correlations were used for analysis with critical alpha set to p ≤ 0.05.
RESULTS:Analysis revealed a positive relationship between VL MT and IPFa (r = 0.64, p = 0.025) and an inverse relationship between LG MT and CMJH (r = -0.54, p = 0.048). There were positive relationships between VL PA and all performance measures and between LG PA and CMJPPa (r = 0.54 to 0.71, p. < 0.05), and inverse relationships between VL FL and CMJPPa and between LG FL and all performance measures (r = -0.59 to −0.67, p < 0.05).
CONCLUSIONS: Better jumpers had larger PA and shorter FL in both VL and LG, and stronger athletes had greater MT in VL, showing that muscle architecture may influence performance variations in volleyball athletes. Considering these findings and the results from previous longitudinal studies demonstrating the effects of heavy strength training on muscle architecture, it is recommended that volleyball athletes incorporate heavy lower body strength training into their training plan in order to increase PA in VL and LG and MT in VL. Based on the relationships found in this study, it is hypothesized that favorable training adaptations in MT and PA will correlate with improved jumping performance and strength in volleyball athletes. Further research should gather longitudinal resistance training, athlete monitoring and testing, and muscle architecture data to explore this hypothesis.