Difference in the Cardiovascular Response to Prolonged Sitting in Men and Women

Abstract

Orthostatic stress, sitting, results in adjustments of cardiovascular variables to maintain blood pressure and is prominent in a variety of occupations. Sitting serves as the control position for head-out water immersion studies. This study addressed gender differences in the cardiovascular response to prolonged sitting. Ten men and 10 women had cardiovascular measurements in the supine position compared with measurements during 2 hours in the seated position (Sit). Supine cardiovascular measurements were similar for both sexes. Heart rate changed similarly for both sexes with Sit. With Sit, men had elevated mean arterial pressure (9 +/- 3%), total peripheral resistance (54 +/- 9%), and decreased cardiac index (-27 +/- 5%), while women had no change in mean arterial pressure, lesser elevations in total peripheral resistance (17 +/- 7%), and lesser decreases in cardiac index (-12 +/- 5%) than men. Thus men, compared to women, had an elevated mean arterial pressure response to prolonged orthostatic stress.

Efeito agudo da intensidade do exercício de força na modulação autonômica cardíaca pós-exercício

“…Nevertheless, it is possible that in the control session, the orthostatic stress caused by prolonged sitting promotes decreased venous return and increased peripheral sympathetic nerve activity stimulating the baroreflex 19,20 . This stimulation, in turn, promotes a decrease in sympathetic nerve activity and increase in cardiac parasympathetic activity 21 .…”

Impacto Do Exercício Contínuo E Intervalado Na Resposta Autonômica E Pressórica Em 24 Horas

“…Comumente utilizada como estratégia controle, a manutenção do sujeito por um longo período de tempo em posição sentada pode gerar ajustes cardiovasculares decorrente do estresse postural e elevar a pressão arterial 21 . Isso ocorreu independentemente da influência mais acentuada do sistema nervoso parassimpático, identificada pelo aumento nos índices RMSSD e pNN50 sobre o grupo controle.…”

“…Isso ocorreu independentemente da influência mais acentuada do sistema nervoso parassimpático, identificada pelo aumento nos índices RMSSD e pNN50 sobre o grupo controle. Aparentemente, independente da ação central favorável à estabilidade da pressão arterial, a compressão dos vasos na região do quadril e os ajustes periféricos decorrentes dessa restrição de fluxo podem desencadear ajustes periféricos que elevam a pressão arterial 21 . Nesse sentido, influências sobre o grupo controle podem ser consideradas como relevantes para interpretação de dados oriundos de pesquisas envolvendo monitorização de variáveis cardiovasculares ao longo do tempo.…”

Post exercise cardiovascular effects of different resistance exercise protocols for trunk and upper limbs

“…In fact, this increment throughout time when subjects remain seated for a long period has already been reported (QUEIROZ et al, 2009;REZK et al, 2006). It has been attributed to the orthostatic stress imposed by the sitting position, which makes the venous return to the heart difficult, deactivating cardiopulmonary receptors that increase peripheral sympathetic activity, promoting vasoconstriction, increasing vascular resistance and, consequently, diastolic BP (GOTSHALL et al, 1994).…”