Recent media reports have suggested that running does not help with weight loss. However, there is compelling scientific evidence that the body reduces its overall energy expenditure after an initial loss of fat mass through a training program, in order to conserve energy and ultimately its fat mass stores. This is a natural insurance developed by our ancestors to prevent famine in times of limited food availability. Nevertheless, a new study has shown that running in the long term prevents an increase in body fat.
Don’t be discouraged if you can’t reduce your weight through running after a promising start. Recent work at the University of Jyväskylä, Finland showed that running helps prevent weight or fat gain in those who continue to run. This is hopeful in maintaining motivation in the coming months, when rapid gains have subsided.
“Our data clearly show that lifelong running training, be it long-distance or repeated short-sprint, leads to lower fat masses than a typical physically active lifestyle and also more than participation in competitive strength sports.”
– Dr. Simon Walker, lecturer in exercise physiology, Faculty of Sport and Health Sciences, University of Jyväskylä
The older sprinters and endurance athletes in the study even had less fat mass than young strength athletes and physically active controls.
„This result definitely motivates me to continue running. With a fat percentage of 16-18%, I would definitely be satisfied in my 70s and 80s,“ Dr. Walker continues.
Lifelong strength training is best for maintaining muscle mass
The same study showed that individuals who engaged in lifelong strength training better maintained their muscle mass compared to those who participated in sprint and long-distance running sports. In addition, older strength trainers had a similar amount of muscle mass to their younger peers.
Therefore, a combined training approach may be most advantageous for optimizing body composition over the entire lifespan. Depending on preference, mood, motivation or seasonal variations, two to three sessions of endurance training and the same for resistance exercise (i.e. 4 to 6 sessions per week) should yield similar results observed in the study athletes,“ Dr. Walker suggests.
„The key may be to prevent an increase in fat mass or a loss of muscle mass from the outset and engage in regular physical activity throughout life. Therefore, lifelong regular training actually helps maintain a healthy body composition. This is not a myth,“ Walker explains.
The study was conducted using data from larger cohort studies (ATHLAS and CALEX family cohorts) led by Dr. Marko Korhonen and Prof. Sulin Cheng. These include men aged 20 to 39 and 70 to 89 who were competitive sprinters, endurance runners, and strength athletes, as well as physically active controls. „Although we only studied men, I see no reason why our results should not also apply to women, especially in light of the effects of menopause and other age-related effects,“ Walker adds.
University of Jyväskylä
Walker, S., et al. (2023). Body composition in male lifelong trained strength, sprint, and endurance athletes and healthy age-matched controls. Frontiers in Sports and Active Living. doi.org/10.3389/fspor.2023.1295906.