Longer Rest Intervals Attenuate Cardiovascular Responses and Perceived Exertion During Resistance Exercise in Untrained Women

Increasing rest interval duration during a strength training resistance exercise protocol attenuates blood pressure (BP) responses in clinical populations with known exaggerations in BP responsiveness. However, it is unknown if increasing rest interval duration will attenuate cardiovascular responses and reduce ratings of perceived exertion in untrained women without pathology. Purpose: To compare the effect of rest interval duration (60-s short rest [SR] vs. 180-s long rest [LR]) during resistance exercise on cardiovascular responses and ratings of perceived exertion in untrained women. Methods: Fifteen young (23 ± 2 years), normotensive (systolic BP: 106 ± 7 mmHg and diastolic BP: 77 ± 6 mmHg) untrained women performed five sets of 10 repetitions of knee extension exercise at 70% of one-repetition maximum on two occasions with differing rest interval durations. Results: During exercise, systolic BP changed from the preexercise baseline (Set 5 Δ mean ± SD: SR: 30 ± 15 mmHg, LR: 21 ± 6 mmHg; analysis of variance condition effect p = .020; (Formula Presented) = .329) and ratings of perceived exertion (Set 5 mean ± standard deviation: SR: 15 ± 2 [6–20 scale], LR: 13 ± 2 [6–20 scale]; Kruskal–Wallis condition effect p = .003; (Formula Presented) = .573) were greater in the SR versus LR condition. During the matched 31–60 s rest time period, the following were greater in the SR versus LR conditions: systolic BP (analysis of variance condition effect p = .002, (Formula Presented) = .503), heart rate (analysis of variance condition effect p = .020, (Formula Presented) = .329), and rate pressure product (Kruskal–Wallis condition effect p < .001, (Formula Presented) = .273). Conclusions: These data suggest that longer rest intervals may reduce cardiovascular strain and perceived exertion when starting resistance exercise training in untrained women.