Sexual dimorphism in heart rate recovery from peak exercise

• Autor(a) principal: Teodósio, Carolina Marques
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.5/13280
• topic: Heart rate recovery; Aerobic capacity; Peak oxygen uptake; Cardiovascular fitness; Passive recovery; Peak exercise; Autonomic function; Vagal reactivation; VO2peak percentile; Sexual dimorphism; Frequência cardíaca de recuperação; Capacidade aeróbia; Pico de consumo de oxigénio; Capacidade cardiovascular; Recuperação passiva; Exercício de pico; Função autónoma; Reativação vagal; Percentil de VO2pico; Dimorfismo sexual; Domínio/Área Científica::Ciências Médicas::Ciências da Saúde

Purpose: Delayed heart rate recovery (HRR) after peak exercise is associated with decreased vagal reactivation and represents a prognostic marker of cardiovascular disease. There is a lack of consensus on whether heart rate recovery (HRR) post-peak exercise follows a sexually dimorphic pattern. We hypothesized that two groups of men and women paired-matched for age and level of cardiorespiratory fitness (peak oxygen uptake - VO2peak percentile) would exhibit similar HRR from peak exercise intensities. Methods: Forty healthy individuals (23 men and 17 women), aged 18 to 28 years, with above average cardiovascular fitness (VO2peak > 50th percentile), performed a peak cycle-ergometer tests with cardiorpulmonary measurements. HRR was obtained at the 1st (HRR1min) and 2nd min (HRR2min) of passive recovery. Student t tests were computed to explore possible differences between men and women for anthropometric and cardiopulmonary data obtained at rest, during exercise and recovery. Multiple linear regression analysis was used to determine whether the relationship between VO2peak and HRR differed between sexes. We used HRR1min and HRR2min as dependent variables and VO2peak, sex and the interaction between sex and VO2peak as independent variables. Results: There were no between-group differences for the VO2peak percentile, RER or peak heart rate (p > 0.05). In contrast, men attained higher peak values for VO2 and work rate (p < 0.05). Both sexes had similar HRR post-peak exercise (p > 0.05). In multiple linear models, VO2peak explained 11.2% of HRR1min variance. As importantly, sex, VO2peak and their interaction were all significant predictors of HRR2min (explained variance: 29.2%) (p < 0.05). When the differences between sexes in VO2peak were controlled for, HRR remained similar between sexes both at 1 and 2 min of recovery. Conclusion: This study shows that, for a given VO2peak percentile (VO2peak percentile > 50th percentile), HRR is similar between men and women. For this reason, we conclude vagal reactivation post-peak exercise does not follow a sexually dimorphic pattern.