THE EFFECTS OF 20 WEEKS BASIC MILITARY TRAINING-PROGRAM ON BODY-COMPOSITION, VO2MAX AND AEROBIC FITNESS OF OBESE RECRUITS

Forty of the most obese recruits going through a 20 weeks Basic Military Training (BMT) program were selected from a cohort of 197 obese recruits. Their TBW, BF, FFW, VO2max, time taken to achieve VT (VT(Time)) and maximal heart rate (HRmax) were measured before, in the middle, and at the end of the program. The means for each of these variables measured in the 3 occasions were analysed for significant differences with the repeated measures analysis of variance. Variables that achieved significant difference were further analysed for pairwise difference with the post-hoc Tukey test. The critical value was set at p < 0.05. Mean TBW and BF decreased from 108.33 +/- 13.1 kg to 90.82 +/- 12.3 kg (p < 0.001), and 34.3 +/- 1.2% to 23.9 +/- 2.3% (p < 0.001) respectively. Mean FW decreased from 37.4 +/- 4.8 kg to 22.0 +/- 4.5 kg (p < 0.001). FFW decreased slightly from a mean of 71.5 +/- 8.6 kg to 69.2 +/- 8.8 kg, which was not significantly different (p > 0.05). Mean VO2max increased from 28.1 +/- 6.3 ml . kg-1 . min-1 to 32.1 +/- 5.1 ml . kg-1 . min-1 (p < 0.001), and mean VT(Time) on similar exercise protocol increased from 13.3 +/- 2.7 minutes to 15.8 +/- 3.8 minutes (p < 0.001). Mean HRmax decreased from 183.5 +/- 12.1 beats . min-1 to 177.3 +/- 10.1 beats . min-1 (p < 0.01). In the post-hoc Tukey test, significant differences were found for TBW (p < 0.01), BF (p < 0.01), and FW (p < 0.01) in all the pairwise comparisons (pre vs mid, mid vs post, and pre vs post tests). Pairwise comparisons were also significant in the pre vs mid test for VO2max (p < 0.01), HRmax (p < 0.01), and VT(Time) (p < 0.01). These three variables were also found to be significant in the pre vs post test comparisons: VO2max (p < 0.01); HRmax (p < 0.05); VT(Time) (p < 0.01), but not significant in the mid vs post test comparisons (p > 0.05). There were only 12 (6.1%) cases of injury from the entire cohort of 197 recruits in the program, which included the 3 cases reported in the present sample of 40 subjects. From the results of this study, it was concluded that the 20 weeks BMT program was effective for BF reduction and maintenance of FFW in the process of TBW loss. The increase in aerobic fitness was also significant (p < 0.05), although improvement in VO2max was mild (4 ml . kg-1 . min-1).