Antihypertensive and volume-depleting effects of mild exercise on essential hypertension.

Abstract

HIDENORI URATA, YOICHI TANABE, AKIRA KJYONAGA, MASAHARU IKEDA, HIROAKI TANAKA, MUNEH1RO SHINDO, AND KLKUO ARAKAWA SUMMARY After a general clinical observation period of over 4 weeks, 20 essential hypertensive subjects (Japanese) were randomly divided into two groups. One group (n = 10; 4 men and 6 women; 51.4 ± 2.8 years of age) agreed to physical training using bicycle ergometer exercise with the intensity at blood lactate threshold for 60 minutes three times a week for 10 weeks, while the other group (n = 10; 4 men and 6 women; 51.0 ± 2.9 years of age) did no particular physical training and was followed once a week as the control. Changes in blood pressure, hemodynamics, and humoral factors of the exercised group were compared with values in the controls. The following significant changes were found only in the exercised group. Blood pressure was significantly (p<0.01) reduced. Whole blood and plasma volume indices were significantly reduced (p<0.05, p<0.01, respectively). The change in ratio of serum sodium to potassium positively correlated with the change in systolic blood pressure (r = 0.76, p<0.02). Plasma norepinephrine concentrations both at rest and at the workload of blood lactate threshold during graded exercise tests were significantly reduced (p<0.05, p<0.02 respectively) after 10 weeks of exercise training. The change in the resting level of plasma norepinephrine positively correlated with that in the mean blood pressure. No such changes were observed in the control group. In both groups, body weight and urinary sodium excretion showed no statistically significant changes. In conclusion, the antihypertensive effect of mild exercise training was confirmed in a well-matched, controlled study, and reduction in blood volume and plasma norepinephrine concentrations had an apparent association. (Hypertension 9: 245-252, 1987) KEY WORDS • blood pressure • training • electrolytes • catecholamines • lactate D ESPITE widespread interest in nonpharmaco logical therapy for hypertension, physical exercise has not gained acceptance for its antihypertensive effectiveness and mechanisms. 12 This may be attributed to the fact that there has been no well-controlled study of factors such as age, sex, race, number, and life-style in matched hypertensive control subjects. Even when positive effects 1 " 8 were obtained, the related mechanisms remained unclear. Supported in part by giants-in-aid from the Japanese Ministries of Education, Science, and Culture (B-58480246), Health and Welfare (60A-6), Uehara Memorial Foundation, and from the Fukuoka University Research Institute.Address for reprints: Kikuo Arakawa, M.D., The Department of Internal Medicine, Fukuoka University, 7-45-1 Nanakuma, Fukuoka, Japan 814-01.Received February 4, 1986; accepted October 31, 1986. We reported the antihypertensive effect of exercise training with the workload at blood lactate threshold and noted a significant reduction of plasma catecholamine concentration and an elevation of plasma prostaglandin E concentration. 9 ' l0 In addit...

Controlled trial of aerobic exercise in hypertension.

“…Additionally, of the 30 studies, only nine were randomized controlled studies using hypertensive controls. 10,12,17,19,21,22,[29][30][31] None compared exercise to a credible alternative treatment or attention/placebo. Furthermore, in two of these controlled studies,12,17 the untreated hypertensive controls exhibited significant average reductions in BP (mainly DBP) similar to their exercised counterparts.…”

The effects of exercise intensity on post exercise hypotension

“…[3][4][5][6][7][8][9][10] Treadmill exercise at similar intensities has also been shown to elicit PEH. Direct comparisons of the effect of exercise intensity on PEH have been limited to 40 and 70% of maximal exercise.…”

Mild exercise activates renal dopamine system in mild hypertensives

“…5,6 The work rate at the blood lactate threshold level (approximately 40-60% of maximum oxygen consumption) was thus individually determined. Using this individual lactate threshold intensity, exercise was performed in an air conditioned laboratory three times a week for 4 weeks.…”

“…Exercise training appears to modify multiple factors that may participate in maintaining elevated BP. 3,4 The anti-hypertensive effect of exercise involves two mechanisms: first, a reduction in sympathetic nerve activity, as reflected in reduced plasma noradrenaline levels; [5][6][7][8][9][10][11] and second, plasma volume depletion, which was substantiated by increases in plasma prostaglandin E, 5 serum taurine, 12 and urinary total dopamine excretion (U-t-DA) 13 and decreases in both the plasma level of endogenous ouabain-like substance and the erythrocyte mean corpuscular volume. 14 In particular, an increase in urinary total (free + conjugated) dopamine (DA) occurs during the early phase of exercise (at week 4) when atrial natriuretic peptide (ANP) levels drop significantly.…”