Purpose - The Aim of this study is to determine and to compare the impact of fat excess on neuromuscular performances during short maximal exercise in male and female students.
Methods - 72 male and 64 female students aged 20 to 23 years were enrolled in this study. After assessing their morphological characteristics (body mass, height and percentage of fat mass), a squat jump test (SJ), a 5 successive jump test (5JT), a hand gripping (HG) and back strength (BS) tests have been conducted for each subject. Male students were re-tested after being weighed down with a weight equivalent to the mean differences in body fat recorded between the two sexes in the form of a loaded worn vest.
Results – Male are 15.7% heavier and 7.4% taller and presented a percentage of fat mass (17.2 ± 1.8%) significantly (p<0.001) lower than that of women subject (25.0 ± 2.5%) (difference male vs female for fat mass: -45.5%). HG, BS, 5JT and SJ performances were significantly higher in males (44±5 kg, 141±2 kg, 11±1 m and 32.4 ± 2,7 cm, respectively) than in females (31.0±4 kg, 81.6±13 kg, 8.7 ± 0.7 m and 21.1 ± 1.9 cm, respectively. In the control (unloaded) condition, the relative difference between males and females represented 23.5% and 34.7% of the male performances for 5JT and SJ, respectively. In the weighted condition, the relative difference between weighted males and females still represented 11.7% and 23.8% of the weighted male performances for 5JT and SJ, respectively. Cancelling the sex difference in fat mass by adding weight in males reduced by 50.1% the sex difference during 5JT and 31.4% and 71.7% for hight and power results, respectively during SJ test.
Conclusion – During short and maximal exercise, male performed better with their hands, back and legs than female students. Excess fat for female students have a disadvantageous effect on vertical and horizontal jumps performances. The persistence of sex differences after weighting of male students indicates that body fat is responsible for 30 to 70 % of the observed differences between sexes performances and power outcome during jump tests.