The Metabolic Syndrome and the immediate antihypertensive effects of aerobic exercise: a randomized control design

<p>Abstract</p> <p>Background</p> <p>The metabolic syndrome (Msyn) affects about 40% of those with hypertension. The Msyn and hypertension have a common pathophysiology. Exercise is recommended for their treatment, prevention and control. The influence of the Msyn on the antihypertensive effects of aerobic exercise is not known. We examined the influence of the Msyn on the blood pressure (BP) response following low (LIGHT, 40% peak oxygen consumption, VO₂peak) and moderate (MODERATE, 60% VO₂peak) intensity, aerobic exercise.</p> <p>Methods</p> <p>Subjects were 46 men (44.3 ± 1.3 yr) with pre- to Stage 1 hypertension (145.5 ± 1.6/86.3 ± 1.2 mmHg) and borderline dyslipidemia. Men with Msyn (n = 18) had higher fasting insulin, triglycerides and homeostasis model assessment (HOMA) and lower high density lipoprotein than men without Msyn (n = 28) (p < 0.01). Subjects consumed a standard meal and 2 hr later completed one of three randomized experiments separated by 48 hr. The experiments were a non-exercise control session of seated rest and two cycle bouts (LIGHT and MODERATE). BP, insulin and glucose were measured before, during and after the 40 min experiments. Subjects left the laboratory wearing an ambulatory BP monitor for the remainder of the day. Repeated measure ANCOVA tested if BP, insulin and glucose differed over time among experiments in men without and with the Msyn with HOMA as a covariate. Multivariable regression analyses examined associations among BP, insulin, glucose and the Msyn.</p> <p>Results</p> <p>Systolic BP (SBP) was reduced 8 mmHg (p < 0.05) and diastolic BP (DBP) 5 mmHg (p = 0.052) after LIGHT compared to non-exercise control over 9 hr among men without versus with Msyn. BP was not different after MODERATE versus non-exercise control between Msyn groups (p ≥ 0.05). The factors accounting for 17% of the SBP response after LIGHT were baseline SBP (β = -0.351, r²= 0.123, p = 0.020), Msyn (β = 0.277, r²= 0.077, p = 0.069), and HOMA (β = -0.124, r²= 0.015, p = 0.424). Msyn (r²= 0.096, p = 0.036) was the only significant correlate of the DBP response after LIGHT.</p> <p>Conclusion</p> <p>Men without the Msyn respond more favorably to the antihypertensive effects of lower intensity, aerobic exercise than men with the Msyn. If future work confirms our findings, important new knowledge will be gained for the personalization of exercise prescriptions among those with hypertension and the Msyn.</p

Efeitos de exercícios aquáticos sobre a aptidão cardiorrespiratória e a pressão arterial em hipertensas Effects of aquatic exercise on cardiorespiratory fitness and blood pressure in hypertensive women

O estudo visou avaliar a influência de um programa de exercícios aquáticos sobre a aptidão cardiorrespiratória e a pressão arterial em mulheres hipertensas. Dez hipertensas participaram do programa de exercícios aquáticos - aeróbicos, de fortalecimento, alongamento e relaxamento - duas vezes por semana durante 7 semanas, totalizando 14 sessões. Foram avaliadas pelo teste de esforço cardiorrespiratório antes e após o desenvolvimento do programa. A pressão arterial foi mensurada ao repouso e aos 10, 20 e 30 minutos após o exercício em cada sessão. As variáveis cardiorrespiratórias não apresentaram alterações significativas após o programa, tanto dos valores de limiar de anaerobiose quanto os do pico de esforço. As pressões arteriais sistólica, diastólica e média de repouso permaneceram estáveis no decorrer do programa. Entretanto, no período pós-exercício, os níveis da pressão arterial sistólica (PAS) e média (PAM) foram significativamente menores, quando comparados aos valores pré-exercício: houve redução média de 6,43 mmHg da PAS e 3,08 mmHg da PAM aos 30 minutos pós-exercício. Assim, o programa de exercícios aquáticos proposto não promove ganho aeróbico efetivo, mas os resultados sugerem que exercícios aquáticos como os propostos, em intensidade próxima ao limiar de anaerobiose, desencadeiam redução dos níveis de pressão arterial no período pós-exercício, em mulheres hipertensas.<br>The aim of this study was to assess the influence of an aquatic exercise program on cardiorespiratory fitness and blood pressure in hypertensive women. Ten hypertensive women took part in the study. The program consisted of aquatic aerobic, strengthening, and stretching exercises in intensity near the anaerobic threshold, besides relaxation, twice a week during 7 weeks, totalling 14 sessions. They were assessed by cardiorespiratory exercise testing before and after program development. Blood pressure was measured at rest before and at 10, 20, and 30 minutes after exercise, at the end of each session. After the hydrotherapy program, cardiorespiratory ranges did not show significant changes, neither at the anaerobic threshold nor at the effort peak. Systolic (SBP), diastolic (DBP), and mean (MBP) blood pressure at rest remained stable all through the program. However, SBP and MBP levels at 30-minute rest after exercises, at the end of the program, were significantly lower when compared to pre-exercise ones: there was a mean 6,43 mmHg SBP decrease and a 3,08 mmHg MBP decrease. The hydrotherapy program thus did not promote effective aerobic increase, but results suggest that the proposed exercises, performed at near-anaerobic threshold, may reduce post-exercise SBP and MBP levels in hypertensive women