Effects of 16-week high-intensity interval training using upper and lower body ergometers on aerobic fitness and morphological changes in healthy men: a preliminary study

Abstract

Yusuke Osawa,1,2,* Koichiro Azuma,3,* Shogo Tabata,3 Fuminori Katsukawa,2 Hiroyuki Ishida,2 Yuko Oguma,2 Toshihide Kawai,4 Hiroshi Itoh,4 Shigeo Okuda,5 Hideo Matsumoto3 1Japan Society for the Promotion of Science, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan; 2Sports Medicine Research Center, Keio University, Kanagawa, Japan; 3Institute for Integrated Sports Medicine, School of Medicine, Keio University, Tokyo, Japan; 4Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan; 5Department of Radiology, School of Medicine, Keio University, Tokyo, Japan *Yusuke Osawa and Koichiro Azuma are co-first authors of this article Abstract: It is unclear whether combined leg and arm high-intensity interval training (HIIT) improves fitness and morphological characteristics equal to those of leg-based HIIT programs. The aim of this study was to compare the effects of HIIT using leg-cycling (LC) and arm-cranking (AC) ergometers with an HIIT program using only LC. Effects on aerobic capacity and skeletal muscle were analyzed. Twelve healthy male subjects were assigned into two groups. One performed LC-HIIT (n=7) and the other LC- and AC-HIIT (n=5) twice weekly for 16 weeks. The training programs consisted of eight to 12 sets of >90% VO2 (the oxygen uptake that can be utilized in one minute) peak for 60 seconds with a 60-second active rest period. VO2 peak, watt peak, and heart rate were measured during an LC incremental exercise test. The cross-sectional area (CSA) of trunk and thigh muscles as well as bone-free lean body mass were measured using magnetic resonance imaging and dual-energy X-ray absorptiometry. The watt peak increased from baseline in both the LC (23%±38%; P<0.05) and the LC–AC groups (11%±9%; P<0.05). The CSA of the quadriceps femoris muscles also increased from baseline in both the LC (11%±4%; P<0.05) and the LC–AC groups (5%±5%; P<0.05). In contrast, increases were observed in the CSA of musculus psoas major (9%±11%) and musculus anterolateral abdominal (7%±4%) only in the LC–AC group. These results suggest that a combined LC- and AC-HIIT program improves aerobic capacity and muscle hypertrophy in both leg and trunk muscles. Keywords: arm-cranking ergometer, cycling ergometer, aerobic capacity, skeletal muscle