New research from Bangor University has shown that exercise training alone does not lead to weight loss in women.

People often take up exercise because they want to lose weight, but sometimes get frustrated because their weight loss is less than they hoped for.

Dr Hans-Peter Kubis, at Bangor University’s School of Sport, Health & Exercise Sciences, designed a bias-free piece of research to see whether women lose weight through exercise alone.

4 and 8 week study

The research group concealed the objective of the research from the participants, using spurious research objectives instead. Moreover, they excluded females who expressed an intention to lose weight from the study because of the possibility that they would restrict their diet.

The participants attended exercise classes, where they performed circuit-training exercises three times a week, in two training studies over 4 and 8 weeks. The researchers measured the body composition of the participants and took blood samples to analyse appetite hormones, which can alter appetite and food intake. They found that both, lean and obese females did not lose weight either after 4 weeks or after 8 weeks of exercise training. However, lean females gained muscle mass. Additionally, the measurements of appetite hormones showed that specific appetite hormones could help to explain why some individuals gained or lost weight after the exercise training.

Dr Kubis said: “Our study showed that using exercise training alone for weight loss is not effective in females, whether lean or obese.

“Our body system is so well regulated, that it always finds a way to compensate for a loss in energy after exercise. Whether they are aware of it or not, someone undertaking more physical activity or exercise may experience increased appetite as a result, and this makes it difficult for people to achieve their goals.”

Women wanting to lose weight should still exercise

Dr Kubis adds: “This does not mean that exercise is not helpful, indeed, it is clear that exercise has massive health benefits. To be effective, exercise training for weight-loss needs to be integrated into a life-style approach to weight-loss, including exercise combined with diet.”

Dr Kubis also suggests that we should not always focus on weight, saying: “Knowing how much fat and muscle we have in our body is much more important than knowing how much we weigh. When we focus on weight alone, we miss the improvements achieved via exercise training.

“Seeing no change on scales may be enough to make people give up on their exercise training, not realising that they have actually improved their body by gaining muscle mass. Exercise facilities, like gyms and leisure centres, should invest in equipment to measure body composition,” he adds.