Author(s): NOLAN, D., DARRAGH, I., GERMAINE, M., LYNCH, A., MANNINEN, M., EGAN, B. , Institution: DUBLIN CITY UNIVERSITY, Country: IRELAND, Abstract-ID: 1136

INTRODUCTION:
Resistance exercise training is commonly used by athletic populations as part of a comprehensive athletic development training program, eliciting morphological and neurological adaptations which contribute to changes in muscle hypertrophy, power and strength. Between-sex differences are evident in many systems of the human body. These between-sex differences are particularly evident in the musculoskeletal system, specifically regarding body composition, muscle structure, and absolute muscular strength.
METHODS:
This systematic review with meta-analysis aimed to; i) quantify the mean absolute and standardised between-group differences in untrained males and females at baseline for fat-free mass, upper body strength, lower body strength, and lower body power; and ii) examine between-group differences comparing males and females regarding hypertrophy, upper body strength, lower body strength, and lower body power in adaptations to resistance exercise training. A systematic review with meta-analysis was conducted on experimental studies conducted before December 2023. The search using the online databases PUBMED, SPORTDiscus, Web of Science, Embase, and other supplementary search strategies yielded 4,468 articles, with 29 articles meeting the inclusion criteria. The articles were analysed using a meta-analytic multilevel maximum likelihood estimator model.
RESULTS:
The results indicate there are significant differences at baseline between untrained males and females for absolute fat-free mass (RMD = 19.35, CI 95% [17.41, 21.29], z = 19.53, p = <0.001), upper body strength (SMD = 2.88, CI 95% [2.67, 3.10], z = 23.47, p < 0.001) and lower body strength (SMD = 2.14, CI 95% [1.84, 2.44], z = 16.21, p < 0.001). In response to resistance exercise training, no significant differences were found for either hypertrophy (g = 0.26, CI 95% [-1.00, 1.51], z = 0.40, p = 0.68), or lower body strength (g = 0.10, CI 95% [-0.06, 0.25], t = 1.38, p = 0.19). A significant effect in favour of females was observed for upper body strength outcomes (g = -0.39, CI 95% [-0.53, -0.26], t = -6.35, p = <0.001).
CONCLUSION:
These analyses would suggest that there are significant differences in anthropometric and physical performance characteristics between untrained males and females; however, males and females respond in a similar manner to resistance exercise training for hypertrophy and lower body strength, with females displaying an advantage for relative upper body strength.