Effect of repeated prolonged exercise on liver fat content and visceral adipose tissue in well-trained older men

Abstract

Introduction: Liver fat (LF) and visceral adipose tissue (VAT) content decreases with training, however, this has mainly been investigated in sedentary obese or healthy participants. The aim of this study was to investigate the effects of repeated prolonged exercise on LF and VAT content in well-trained older men and to compare baseline LF and VAT content to recreationally active older men.

Method: A group of five well-trained older men were tested before and after cycling a total distance of 2558 km in 16 consecutive days. VAT content and body composition was measured using DXA before a bicycle ergometer test was performed to determine maximal fat oxidation (MFO), maximal oxygen consumption ( ${\mathrm{VO}}_{2_{\max }}$ ), and the relative intensity at which MFO occurred (Fat_max). LF content was measured on a separate day using MRI. For comparison of baseline values, a control group of eight healthy age- and BMI-matched recreationally active men were recruited.

Results: The well-trained older men had lower VAT (p = 0.02), and a tendency toward lower LF content (p = 0.06) compared with the control group. The intervention resulted in decreased LF content (p = 0.02), but VAT, fat mass, and lean mass remained unchanged. ${\mathrm{VO}}_{2_{\max }}$ , MFO, and Fat_max were not affected by the intervention.

Conclusion: The study found that repeated prolonged exercise reduced LF content, but VAT and ${\mathrm{VO}}_{2_{\max }}$ remained unchanged. Aerobic capacity was aligned with lower LF and VAT in older active men.

Keywords: aerobic capacity; liver fat; older men; repeated prolonged exercise; visceral adipose tissue.