Indexed on: 25 Jan '17Published on: 25 Jan '17Published in: Journal of strength and conditioning research / National Strength & Conditioning Association
Resistance exercise (RE) is commonly employed to elicit skeletal muscle adaptation. Relative intensity of a training load links closely with the outcomes of regular RE. This study examined the RPE responses to acute bouts of RE using imposed (40% and 70% of 1RM) and self-selected loads (SS) in recreationally trained women. Twenty physically active women (23.15 ±2.92 yrs.) who reported regular RE training of at least three weekly sessions for the past year, volunteered to participate. During the initial visit, participants completed one repetition maximum (1RM) testing on four exercises in the following order: leg extension, chest press, leg curl, and lat pull-down. On subsequent visits, the same exercises were completed at the SS or imposed loads. RPE was assessed following the completion of each set of exercises during the three RE conditions using the Borg-15 category scale. Self-selected loads corresponded to an average of approximately 57%1RM (± 7.62). Overall, RPE increased with load [40%1RM = 11.26 (± 1.95); SS 57%1RM = 13.94 (± 1.58); and, 70%1RM = 15.52 (± 2.05)]. Reflecting the linear pattern found between load and perceived effort, the present data provide evidence that RPE levels less than 15 likely equate to loads which are not consistent with contemporary ACSM guidelines for enhancing musculoskeletal health which includes strength and hypertrophy. Women desiring increases in strength and lean mass likely need to train at an exertion level at or surpassing a rating of 15 on the Borg-15 category. The current manuscript examined the modification of training load on perceived exertion but other variables, such as the number of repetitions completed, may also be targeted to achieve a desired rating of perceived exertion. The primary understanding is that women who engage in RE may not self-select loads that are consistent with the ACSM recommendations for musculoskeletal health.