Comparison of block versus weekly undulating periodization models on endocrine and strength changes in male athletes

The aim of this study was to examine the hormonal and strength responses to different periodization models of resistance training in male athletes. Eighteen experienced resistance trained males were randomly assigned to either a block (BP; n=10; age: 23.7±2.9 yr; body mass: 78.5±11.3 kg; height: 1.77±0.05 m) or weekly undulating (WUP; n=8; age: 26.0±5.7 y; body mass: 78.9±12.4 kg; height: 1.79±0.05 m) periodized resistance training program. Both programs consisted of four-training sessions per week for 15 weeks, and each was equated for training volume. Analysis of variance was used to compare strength performance and changes in hormone response between groups. Salivary samples were taken before and after the first and the last workout of each mesocycle of the training program and assessed for testosterone (T) and cortisol (C). Maximal strength testing occurred before and after the 15-week training program. A greater increase (p=.040) in bench press strength was observed in BP compared to WUP, while no between group differences were noted for lower body isometric strength (p=.168) and lean body mass (p=.344). Significant elevations in T were seen in both groups following the power training phase, while no differences were noted between BP and WUP during any other training cycle. Results indicated that BP stimulated greater gains in upper body strength compared to WUP. In addition, the power phase of training may provide a greater anabolic hormone response.