DOES THE NUMBER OF JOINTS INVOLVED IN EXERCISE PROMOTE CHANGES IN ENERGY EXPENDITURE?

ABSTRACT Introduction: The benefits of strength training (ST) include not only strength improvement but also favorable body composition changes, which has led to a considerable increase in the indication of this training method in overweight and obese individuals, and has made the investigation of outcomes attributed to different manipulations of ST variables an important task. However, acute metabolic responses related to energy expenditure (EE) associated with the manipulation of exercises which, in turn, are associated with the number of joints involved in movement, are still inconclusive. Objective: To verify the influence of the number of joints involved in movement on EE with equalized volume in ST at different intensities. Methods: This training program was held on alternate days, with a 48-hour interval between each session, and with two randomized protocols, as follows: multi joint protocol with four common exercises for ST participants compared to the single joint protocol with four exercises. Each protocol was evaluated at three training intensities (90%, 75% and 60% of 1-RM) according to the one-repetition maximum test. Results: Significant increases in EE were observed in the multi joint session as compared to the single joint session: 90% 1-RM multi joint 246.80 ± 26.17 kcal vs single joint 227.40 ± 24.54 kcal (∆ -7.86, 95% CI 7.33; 31.46; t 3.44; p <0.05); 75% 1-RM multi joint 124.13 ± 25.40 kcal vs single joint 111.80 ± 22.78 kcal (∆ -9.93, 95% CI 3.25; 21.41; t 2.91; p <0.05); 60% 1-RM multi joint 70.80 ± 6.28 kcal vs single joint 64.40 ± 6.72 kcal (∆-9.04, 95% CI 3.95; 8.84; t 5.60; p <0.05). Conclusion: Multi joint exercises may be a variable to consider when EE balance is the main target of the ST program. However, further studies are needed to supplement our findings. Level of evidence II; Diagnostic studies-Investigating a diagnostic test.