Comparison of efficacy of continuous and intermittent walking exercise on blood pressure and renal function in elderly hypertensive subjects: study protocol for a randomized controlled trial

Abstract

Background and objectives: Hypertension (HTN) affects millions of people worldwide. HTN plays a major etiologic role in the development of cerebrovascular disease, ischemic heart disease, cardiac and renal failure. Although the treatment of HTN has been shown to prevent cardiovascular disease and to extend life, HTN remains inadequately managed everywhere. Exercise therapy has been shown to enhance efficacy of medication treatment. Even regular physical activity of lower intensity and duration has been shown to be associated with about a 20% decrease in mortality. Nevertheless, elderly individuals are limited in the duration of exercise due to their decline in physical fitness. Therefore, we aim to evaluate and compare the efficacy of continuous and intermittent exercise on blood pressure, renal function, as well as blood pressure-related variables including cardiac autonomic function, cardiovascular risks, and oxidative stress in elderly individuals with HTN. Subjects and methods: This is a prospective, randomized controlled trial. A total of 50 elderly subjects with HTN will be recruited from Mueang District, Chonburi Province, Thailand. The subjects will be randomized into two groups and undergo walking exercise training. The continuous walking exercise group (n = 25) will perform walking exercise continuously for 30 minutes/day, 3 days/week for 12 weeks. The intermittent walking exercise group (n = 25) will perform walking exercise intermittently for 10 minutes/session, 3 consecutive sessions/day with 1-minute interval between sessions, 3 days/week for 12 weeks. The primary outcome measures will be systolic and diastolic blood pressure levels and renal function (serum creatinine and uric acid concentrations, estimated glomerular filtration rate, and estimate creatinine clearance) before and 12 weeks after intervention. The secondary outcome measures will be cardiac autonomic function, cardiovascular risks (blood glucose, serum lipid profile, atherosclerogenic index), and oxidative stress (plasma malondialdehyde and blood glutathione and glutathione disulfide) before and 12 weeks after intervention. The recruitment of subjects began on May 2, 2018. Outcome measures will be analyzed on October 29, 2018. This trial will be completed on October 27, 2018. Protocol version: 1.0. This trial has been approved by the Human Ethics Committee of the Burapha University on January 15, 2018 (approval No. 218/2560). Discussion: The intermittent walking exercise can be applied as an effectively therapeutic treatment of HTN in elderly individuals. Trial registration: This trial has been registered in the Thai Clinical Trials Registry (TCTR) (identification No. TCTR20180226003) on February 23, 2018.