Effects of a single bout of walking on postprandial triglycerides in men of Chinese, European and Japanese descent: a multisite randomised crossover trial

Abstract

Introduction: Elevated non-fasting triglyceride (TG) concentrations are a risk factor for cardiovascular diseases but can be reduced after acute exercise. Ethnic-based differences in the magnitude of postprandial lipaemia and the extent that acute exercise reduces postprandial TG are poorly characterised across some ethnicities including those of East Asian origin. This paper describes the protocol of a multisite randomised crossover study comparing the effect of acute walking on postprandial TG in two groups of East Asian men with European men.

Methods and analysis: Twenty Japanese, 20 Singaporean Chinese and 20 white British healthy men (21-39 years) recruited from Japan, Singapore and the UK, respectively, will complete two, 2-day trials. Fasted and postprandial venous blood samples and arterial blood pressure measurements will be taken over 6 hours the day after either: (1) 60-min treadmill walking; or (2) a rest day of normal living. The primary outcome is the difference in postprandial TG among ethnic groups after rest and walking. Secondary outcomes include cholesterol, glucose, insulin, ketone bodies, preheparin lipoprotein lipase, C-reactive protein and systolic/diastolic blood pressure.

Ethics and dissemination: The study was approved by the Ethics Review Committee on Research with Human Subjects of Waseda University and the Nanyang Technological University Institutional Review Board. Relevant approval will be obtained from the UK site. Research findings will be disseminated through peer-reviewed journal publication and health conferences.

Trial registration number: UMIN000038625.

Keywords: cardiovascular; exercise physiology; lipids; physical activity; postprandial lipaemia.

Figure 1

Study recruitment and design.

Figure 2

A schematic representation of the study protocol. On day 1 of the walking trial, participants will carry out their usual free-living activities throughout the day and complete 1 hour of brisk walking in the laboratory from 1600 hours to 1700 hours. The control trial will be identical except that participants will rest in the laboratory from 1600 hours to 1700 hours. On day 2 of both trials, participants will consume a standardised breakfast and then sit in a chair (reading, writing, working at a computer or watching television) in the laboratory until 1500 hours. VAS, visual analogue scales.