University of Tehran Press Sport Biosciences 2008-9325 7 1 2015 04 21 Response of Strength, Power and Muscle Endurance to Resistance Training with Different Rest Intervals Response of Strength, Power and Muscle Endurance to Resistance Training with Different Rest Intervals 77 91 54278 10.22059/jsb.2015.54278 FA Vahid Valipour Dehnou Assistant Professor, Department of Physical Education and Sport Sciences, Faculty of Humanities, Lorestan University, Khorramabad, Iran Hosein Mansournejad MSc. Student Exercise Physiology, Faculty of Humanities, Lorestan University, Khorramabad, Iran Reza Gharakhanlou . Associate Professor, Department of Physical Education and Sport Sciences, Faculty of Humanities, Tarbiat Modares University, Tehran, Iran Firouz Sharafi PhD Student of Exercise Physiology, Alborz Campus of University of Tehran, Alborz, Iran Journal Article 2013 07 24 Researchers and coaches are constantly looking for the most effective ways to enhance athletic performance. The aim of this study was to investigate the response of strength, power and muscle endurance to resistance training with different rest intervals. 16 male volunteers were selected and divided randomly into two groups. Group A (<em>n</em>=8, age 22±2.55 yr, height 174.20±6.14 cm, weight 64.20±6.33 kg) performed resistance training with constant rest intervals (120 sec.) and group B (<em>n</em>=8, age 22±3.54 yr, height 176.40±6.50 cm, weight 64.60±6.38 kg) with incremental rest intervals (90, 120, 150 sec.) 3 days per week for 6 weeks. To determine strength, power and muscle endurance, 1RM, bench press, throwing medicine ball and maximum repetition of bench press with 30% of 1RM tests were used respectively. Blood samples were collected 3 minutes before and 2 minutes after the 17^th session to measure blood lactate. Paired samples and independent samples t tests were used for data analysis (<em>α</em><0.05). Results showed that strength, power and muscle endurance significantly increased in both groups (<em>P</em><0.05), but group B showed a greater percentage change in all tests. Blood lactate significantly increased after the resistance training compared with the rest interval but this increase was less in group B. It can be concluded that resistance training with progressive rest intervals is more important for increasing strength, power and muscle endurance compared with constant rest intervals. Researchers and coaches are constantly looking for the most effective ways to enhance athletic performance. The aim of this study was to investigate the response of strength, power and muscle endurance to resistance training with different rest intervals. 16 male volunteers were selected and divided randomly into two groups. Group A (<em>n</em>=8, age 22±2.55 yr, height 174.20±6.14 cm, weight 64.20±6.33 kg) performed resistance training with constant rest intervals (120 sec.) and group B (<em>n</em>=8, age 22±3.54 yr, height 176.40±6.50 cm, weight 64.60±6.38 kg) with incremental rest intervals (90, 120, 150 sec.) 3 days per week for 6 weeks. To determine strength, power and muscle endurance, 1RM, bench press, throwing medicine ball and maximum repetition of bench press with 30% of 1RM tests were used respectively. Blood samples were collected 3 minutes before and 2 minutes after the 17^th session to measure blood lactate. Paired samples and independent samples t tests were used for data analysis (<em>α</em><0.05). Results showed that strength, power and muscle endurance significantly increased in both groups (<em>P</em><0.05), but group B showed a greater percentage change in all tests. Blood lactate significantly increased after the resistance training compared with the rest interval but this increase was less in group B. It can be concluded that resistance training with progressive rest intervals is more important for increasing strength, power and muscle endurance compared with constant rest intervals. https://jsb.ut.ac.ir/article_54278_e6c492f583f83519ec46d821b489b71a.pdf