Abstract

Author(s): Pablo ARAVENA-SAGARDIA1, Alán GARCÍA-SANDOVAL1, Tomás HERRERA-VALENZUELA2,3, Braulio Henrique MAGNANI BRANCO4, Rodrigo VARGAS-VITORIA5, Pablo VALD

Introduction: Resistance training exercises must be adapted to people’s characteristics and dosed individually to achieve maximum benefits. Aim: To compare the effects of a resistance training program on body composition and maximum strength in physically active university students, according to their baseline body mass index (BMI).

Material and methods: Twenty-four Physical Education students (15 males and 9 females) completed a supervised resistance training program that lasted eight weeks (16 sessions). The students were previously distributed into a group below the mean BMI group (BMG; n = 11; 7 males and 4 females) and above the mean BMI group (AMG; n = 13; 8 males and 5 females). Body weight, height, BMI, body composition (adipose mass and muscle mass), and maximum upper body strength (bench press and military press), and lower body strength (parallel squat [45°] and deadlift) were measured through a one-repetition maximum (1RM).

Results: Fat mass decreased significantly (p< 0.05) with a small effect size (d< 0.30) in both groups (BMG and AMG). In contrast, muscle mass increased significantly (p= 0.008) only in AMG with a small effect size (d= 0.36). Maximum upper and lower body strength increased significantly (p< 0.05) with a small and moderate effect size (d< 0.80) in the BMG and AMG. Comparisons between the groups revealed no significant differences.

Conclusions: An eight-week resistance training program significantly reduces fat mass and a significant increase in maximal upper and lower body strength in physically active university students, independent of their baseline BMI. However, only AMG achieves a significant increase in muscle mass