EFFECT OF RESISTANCE TRAINING AND DETRAINING ON METABOLIC MARKERS

Background and objective The aim of this study was to determine how resistance training and detraining later affected the growth factors, inflammatory markers, and bone metabolism markers in healthy male college students. Material and methods Twenty-two young adults participated in 12 weeks weight training (WT) program. Exercise intensity for WT group included the following: step1, 70% of 1 repetition maximum (1RM); step 2, 80% of 1RM; and step3, 90% of 1RM. After 12 weeks, were classified to the 6 weeks CT(continued training group) and 6 weeks DT(detraining group). In the body composition test, height, weight, body mass index (BMI), % fat, and lean body mass (LBM) were measured by electric impedance. Blood collection was carried out before, after 6 weeks, after 12 weeks, and after 18 weeks of training. In blood analysis, growth factors (GH, IGF-1, and testosterone), inflammatory markers [IL-6, tumor necrosis factor-a (TNF-alpha), and c-reactive protein (CRP)], and bone metabolism markers [osteocalcin (OC) and alkaline phosphatase (ALP)] were analyzed. Results Results showed that IGF-1 level was significantly decreased after 12 weeks of training compared to that prior to training. Testosterone level was also significantly decreased after 6 weeks and 12 weeks of training. Levels of IL-6, TNF-alpha, and CRP showed no significant differences by training period. Both OC and ALP levels significantly increased after 6 weeks and 12 weeks of training compared to those prior to training. Detraining period IGF-1 level after 18 weeks was higher than that after 12 weeks in the CT group. IL-6 level after 18 weeks was lower compared to that at 12 weeks in the CT group. TNF-alpha level after 18 weeks was lower compared to that after 12 weeks in both groups. ALP level after 18 weeks was significantly higher compared to that after 12 weeks in the CT group. Conclusions Resistance training induced bone metabolic markers (OC and ALP) after 12 weeks. In addition, training period of more than 18 weeks is needed to reduce inflammatory markers (IL-6 and TNF-alpha). Six weeks of detraining does not affect metabolic markers in healthy young adults.