This study assessed the exercise tolerance and cardiorespiratory responses during 2-month weight-loss programmes using the 6-minute walking test (6MWT) in obese children. Twenty-eight male obese children were randomly assigned to either a control group (C), an energy restriction group (R), an exercise training at maximum lipid-oxidation (LIPOXmax) group (E), or an energy restriction/training group (RE). The body composition, the submaximal incremental cycling exercise, and the 6MWT were performed before and after the 2-month programme. After the programme, RE group showed a significant improvement of body composition, and an increase of 6-minute walking distance. Similarly, maximum oxygen uptake calculated according to the American College of Science Medicine guideline (VO2maxACSM) and VO2max predicted from 6MWD were respectively higher than the R or E groups. Bland-Altman analysis highlighted an agreement of these two methods of VO2max measurement. Moreover, in all participants the 6MWD was significantly correlated with VO2maxACSM and LIPOXmax before the programme as well as their changes in percentage over the programme.
The authors concluded that a 2-month weight-loss programme including energy restriction and exercise training targeted at LIPOXmax improved body composition and cardiorespiratory tolerance in obese children. Furthermore, the 6MWT could be considered as a useful and reliable tool for the assessment and the follow-up of cardiorespiratory responses during weight-loss programme in obese children.