Related Experiment Video
Updated: Oct 16, 2025
A Chronic High-Intensity Interval Training and Diet-Induced Obesity Model to Maximize Exercise Effort and Induce Physiologic Changes in Rats
Published on: April 28, 2023
Aberrant Mechanical Efficiency during Exercise Relates to Metabolic Health and Exercise Intolerance in Adolescents
Wouter M A Franssen1,2, Guy Massa2,3, Bert O Eijnde2
1REVAL-Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, 3590 Diepenbeek, Belgium.
Background:
Mechanical efficiency (ME) might be an important parameter evaluating cardiometabolic health and the effectiveness of physical activity interventions in individuals with obesity. However, whether these cardiometabolic risk factors may relate to ME in adolescents with obesity is not known yet. Therefore, this study aims to compare the mechanical efficiency during maximal exercise testing between adolescents with obesity and lean adolescents, and to examine associations with exercise tolerance and metabolic health.
Methods:
Twenty-nine adolescents with obesity (BMI SDS: 2.11 ± 0.32, age: 13.4 ± 1.1 years, male/female: 15/14) and 29 lean (BMI SDS: -0.16 ± 0.84, age: 14.0 ± 1.5 years, male/female: 16/13) adolescents performed a maximal cardiopulmonary exercise test from which the net mechanical efficiency (MEnet) and substrate oxidation (carbohydrates and lipids) were calculated. Indicators for peak performance were collected. Biochemistry (lipid profile, glycaemic control, inflammation, leptin) was studied in fasted blood samples. Regression analyses were applied to examine relations between MEnet and exercise tolerance or blood variables in the total group.
Results:
Peak work rate (WRpeak), oxygen uptake (V˙O2peak)/WRpeak, ME, and MEnet were significantly lower (p < 0.05) in adolescents with obesity compared to their lean counterparts (p < 0.05). Furthermore, a reduced MEnet was independently related to a lower WRpeak (SC β = 2.447; p < 0.001) and elevated carbohydrate oxidation during exercise (SC β = -0.497; p < 0.001), as well as to elevated blood low-density lipoprotein cholesterol (SC β = -0.275; p = 0.034) and fasting glucose (SC β = -0.256; p = 0.049) concentration.
Conclusion:
In adolescents with obesity, the mechanical efficiency is lowered during exercise and this relates to exercise intolerance and a worse metabolic health.
More Related Videos
12:59Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People
Published on: July 5, 2017
09:40Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle
Published on: January 19, 2017
Related Concept Videos
01:17Exercise and Cardiac Output
Sustained exercise increases the muscles' oxygen demand, which can be...
01:20Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...