Differences in explosive strength values for students of the faculty of physical education and sports (male) according to body mass index levels

Background and Study Aim. Explosive strength/muscular strength is demanded at the level of different body segments and regions in most sports. The purpose of the research: is to identify the differences in the manifestation of explosive force between groups of underweight, normal weight and overweight university students; to determine the associations between the anthropometric parameters and the value of the results in the applied tests. Material and Methods. The investigated group consists of 147 students (men) of the Faculty of Physical Education and Sport, divided into 3 distinct groups for the analysis of the results: underweight (age=20.40±1.18, BMI=17.81±0.93), normal weight (age=20.504±1.671, BMI =22.24±1.67) and overweight (age=22.44±2.24, BMI=28.01±2.74). 7 tests were used to evaluate the explosive strength of the lower body (Vertical Jump Test, Standing Long Jump Test, 3-Hop Test, The multiple 5 bounds test, 30s Lateral double leg hop test, 30s Continuous vertical jumps, Speed Test 10m). A number of 6 tests were used to evaluate the explosive strength of the upper body (Overhand ball throw, Shot put, Overhead Medicine Ball Throw-forward, Overhead Medicine Ball Throw-backward, Medicine ball chest throw, 30s Plyometric Push-Ups). Results. Univariate test results indicate F values associated with significant thresholds at the lower body level (P<0.05) for tests based on horizontal jumps (Standing Long Jump, 3-Hop Test and The multiple 5 bounds test), where underweight and normal weight have the better average scores. At the level of the upper body, the situation is changed (for Shot put and medicine balls throws), where the overweight have the best average values, followed by the normal weight, and the worst results are found for the underweight group (P<0.05). Only for the Overhand ball throw and 30s Plyometric Push-Ups, the superiority of the overweight is not statistically confirmed (P>0.05). Correlation calculation (Pearson values) indicates positive associations between body height and vertical and horizontal jumps (except for those repeated for 30s), but negative associations of BMI and body mass with jump-based tests. However, BMI and body mass are moderately, positively and significantly correlated with throw-based tests (P<0.05). Conclusions. We can state that the classification of students in different BMI categories generates differences in explosive strength values between the 3 studied groups. The comparisons indicate the superiority of underweight and normal weights over overweight in all lower body explosive strength tests. The comparisons indicate also the significant superiority of overweight in the medicine ball and shot put tests over normal and underweight. The obtained results cannot be generalized, due to the small size of the underweight and overweight samples. Further investigations on larger groups of university students being necessary.