Effects Of High Intensity Resistance Training Protocols On Cardiovascular Parameters In Hypertensive Women

Abstract

Establishing an ideal resistance training (RT) protocol for hypertensive individuals has been a challenging task, given the many variables that should be considered in these protocols. In general, the protocols established for hypertensive individuals involve the use of lower loads and a higher number of repetitions. However, recent evidence has shown that this approach might generate negative effects on cardiovascular parameters, especially in the short term, which may indicate a potential risk to participants. In contrast, the use of higher loads but with a reduced number of repetitions does not seem to cause such overload to the cardiovascular system and have been shown to promote comparable gains in variables such as strength, body composition, balance and quality of life. PURPOSE: Analyze the effects of different resistance training protocols with lower and higher loads on cardiovascular parameters in hypertensive women. METHODS: A randomized crossover design clinical trial was conducted with 20 postmenopausal hypertensive women who underwent a control session and two RT protocols involving 6 and 15 repetition maximum (RM). The cardiovascular variables were collected pre, immediately post, 1 h post, and 24 h post each protocol. Repeated-measures ANOVA was used. RESULTS: The HR indices were higher in 15RM protocol immediately and 1 hour after the exercise (86.55±12.81; 75.96±11.51) when compared with control (67.14±7.38; 66.01±8.88) and 6RM (78.56±9.73; 71.29±9.40) sessions (p<0.05). The rate-pressure product indices that represent the myocardial workload also were higher in 15RM protocol immediately (12089.59±3022.77) and persisted in 1 hour after (9947.44±2184.58) the exercise when compared with control (8830.83±1394.09; 8800.71±1498.79) and 6RM (11002.58±1986.82; 9226.33±1604.68) sessions (p<0.05). CONCLUSIONS: Performing high intensity RT with lower loads and a higher number of repetitions seems to promote higher heart rate and rate-pressure product, which may be related to an increased cardiovascular stress. Although the 6RM protocol also raises these parameters immediately after, these changes were not evident within 1 hour and may serve as an indication that the use of high loads may be safe to the cardiovascular system in hypertensive individuals.