It is generally accepted that the implementation of high intensity resistance training can lead to several physiological adaptations such as muscular strength. In recent years, many individuals have been attracted to weight training to increase muscular strength. One of the most important variables affecting muscular strength improvement is the training system. Two common resistance training systems are single set and multiple sets. Which training system is superior remains undetermined. The objective of this study was to examine the effects of 8 weeks single set versus multiple set resistance training on upper and lower body muscular strength among untrained male adults. Twenty four apparently healthy untrained males (age: 20.5 ± 1.8 years, body height: 174.9 ± 4.2 cm, body mass: 72.3 ± 3.2 kg, and body fat mass percentage: %18.2 ± 1.3) were selected randomly and assigned into two groups: single set (SS) and multiple sets (MS). Both groups completed 8 weeks of high intensity resistance training (70 80% of one repetition maximum) with 8 10 repetitions for 3 times per week which SS and MS groups performed one set and three sets of each exercise, respectively. Dependent variables involving maximal muscular strength using one
repetition maximum were measured before and after the intervention. Significance level was set at P < 0.05. No differences existed among both groups at baseline for depended variables. A paired Student’s t test and an independent sample t test revealed significant increases in upper and lower body maximal muscular strength in both groups after the intervention (P < 0.05), and upper and lower body maximal muscular strength increased significantly more in MS group compared with SS group (%23.43 increase in MS group vs. %12.70 increase in SS group). The results of this study showed that MS resistance training had a significant better effect than SS resistance training to improve upper and lower body muscular strength after 8 weeks of resistance training among untrained male adults.