Effects of imposed and self-selected exercise on perceptual and affective responses, muscle function, quality, and...

The objective of the present randomized trial was to verify the effect of twelve weeks of strength training with self-selected and imposed loads on muscle function, functionality, muscle quality, and perceptual and affective responses in elderly men and women. Twenty-four volunteers were divided into two groups of 12 individuals each: self-selected group (SS) (8 women, 4 men; mean age=66.92±6.18 years) and imposed group (IMP) (8 women, 4 men; mean age=65.33±2.42 years). The strength exercise program lasted 12 weeks (3 d/w). All exercises were performed on machines. The SS group was instructed to select a weight that would allow them to complete three sets of 10 repetitions, while the IMP group had the load imposed by the researchers following the exercise prescription model recommended by American College of Sports Medicine (ACSM). Rated perceived exertion (RPE) and affective responses were recorded at the end of each session. Muscle function, functionality, and muscle quality were assessed before and after the intervention. Both groups demonstrated similar improvements in strength and functional capacity. Furthermore, the SS group reported lower RPE and higher affective responses compared to the IMP group at 8-12 weeks. In summary, the findings from this study highlighted the effectiveness of both IMP and SS intensity resistance training programs in enhancing muscle strength and functional capacity among older adults.