Background: Researchers, coaches and athletes are constantly looking for the most effective and efficient ways to enhance athletic performance. The aim of this study was to investigate the response effects of two resistance training methods with different rest intervals on muscular strength and power and blood lactate level. Materials and methods: Sixteen healthy female volunteers were divided randomly into two groups: constant rest intervals group (n=8, age:23±3.74years, height:164.20±2.15cm, weight:64.80±4.57Kg) and increasing rest intervals group (n=8, age:22±2.92years, height:166.40±6.47cm, weight:67.60±3.57Kg). Resistance training was performed three days per week for six weeks. For strength and power measurements, 1RM and throwing medicine ball (5Kg) tests were used, respectively. Blood lactate level was measure through ELISA. ANCOVA, paired-samples t-test and independent-samples t-test were used to identify any statistical differences. SPSS software was used for data analysis and a p≤0.05 was considered significant. Results: Data was show that both resistance training methods caused a significant increase in muscular strength and power and blood lactate concentration (p<0.05). However, difference between two methods was seen only for muscular power (p=0.049). Conclusion: The results showed that two resistance training methods with different rest intervals have no different effects on muscular strength and blood lactate alteration. It may be as a result of same mean time of rest and short training period.