Insulin sensitivity, body composition and adipose depots following 12 w combined endurance and strength training in dysglycemic and normoglycemic sedentary men

Abstract

Context: Insulin resistance and dysglycemia are associated with physical inactivity and adiposity, and may be improved by exercise. Objective: Investigate the effect of exercise on insulin sensitivity, body composition and adipose depots in sedentary men with (n = 11) or without (n = 11) overweight and dysglycemia. Material and methods: Euglycemic-hyperinsulinemic clamp, ankle-to-neck MRI, MRS, muscle and adipose tissue biopsies before and after 12 weeks combined strength and endurance exercise. Results: Insulin sensitivity, VO₂max, strength, whole-body and muscle fat content, and abdominal adipose depots were improved without obvious differences between normo- and dysglycemic men. Hepatic fat, waist circumference and subcutaneous adipose tissue were reduced in the dysglycemic group. For both groups plasma adiponectin was reduced, whereas IL-6 was unchanged. Visceral fat was preferentially lost compared with other adipose depots. Discussion and conclusion: Body composition, fat distribution and insulin sensitivity improved following training in sedentary middle-aged men with and without dysglycemia.

Keywords:

• Adipokines
• muscle fat
• myokines
• prediabetes
• visceral fat

Acknowledgements

Acknowledgements go to Anne Randi Enget at the Department of Nutrition University of Oslo for invaluable laboratory expertise, Anita Sjøenden at Oslo University Hospital Ullevål for help with MR scanning, and Åse Halsne and Gøril Vinje at Oslo University Hospital Aker for their effort during clamp-testing. Thanks also to Linda Sunde and Gunnar Åmlid at the Department of Nutrition for help with FFQ, and Magne Thoresen at the Department of Biostatistics University of Oslo. The training intervention was performed at the Department of Physical Performance, Norwegian School of Sport Sciences; Tor I Gloppen, Torstein Dalen, Håvard Moen and Anders J Kolnes are thanked for excellent help as strength training instructors, and Katrine A Krog, Øyvind Skattebo and Eirin N Rise for help as spinning instructors, Professor Truls Raastad and Tormod Skogstad for sharing their knowledge on muscle biopsies, and Eirik Nossum and Stian Jelstad for help during endurance testing. All others helping as instructors or with data collection remain unnamed, but their contributions are much appreciated and made the intervention successful. Finally, the participants are thanked for all the time spent on training and tests, and for a positive attitude throughout the study.

Declaration of interest

No conflicts to declare. The study was supported by grants from: Helse Sør-Øst, Institute of Basic Medical Sciences, UiO, Johan Throne-Holst Foundation for Nutrition Research, Freia Medical Research Foundation, Anders Jahre’s Foundation for Medical Research, and an EU-financed FP7 project (NutriTech grant agreement no: 289511). We also thank the Simon Fougner Hartmann Foundation providing financial support for an YSI glucose analyser.