7 jours d’entraînement de force réduisent les cellules adipeuses chez les rats

Auteur / Éditeur: Barış Özdemir•12 October 2026

✓ Vérifié éditorialement

Researchers at the University of Campinas in Brazil conducted experiments with obese mice for a week to examine the effects of strength training on fat cells before weight loss began. When people lose weight, many biological changes occur in the body, so it can be difficult for researchers trying to measure the effects of nutrition, exercise, or any other factor, to separate these weight loss effects from what they are trying to measure. The researchers looked at the visceral (inner) fat around the organs of the mice before they started losing weight, in order to clarify the effects of strength training on fat cells before weight loss began. link

Compared to sedentary obese mice, the mice that were put on a strength training program had less fat around their intestines and smaller cells, which typically indicate healthier fat tissue. Positive changes were also observed in fat storage and fat breakdown signals.

The results of the study, published in Life Sciences, show that strength training improves metabolic health before any weight loss; however, the findings need to be replicated in human studies. link

“People think that if they are doing strength training for two months and they are not losing weight, it is useless,” says obesity surgery expert Leandro Moura. “But what we saw in this study was that, even after just seven days of strength training – without any weight loss – the molecular pathways that promote fat accumulation were less active, while those that stimulate fat breakdown were more active.”

To simulate the effects of weight lifting on the animals, the researchers had obese mice with weights attached to their tails climb a 70-centimeter (27.6-inch) ladder. The sessions consisted of a total of seven, with 20 climbs, 60-90 seconds of rest periods, and the mice working at 70% of their maximum capacity.

“We calculated the weight that each mouse could carry while climbing the ladder,” explains Moura. “Of course, it is not possible to reproduce the full strength training exercises that a person would do; however, we stimulated a similar effort in the body, with more intense contractions, in a way that mimics a strength training session specific to humans.”

Then, samples of fat tissue taken from the mice that had done the strength training were compared with the tissues of obese mice that had not done any exercise.

In addition to the benefits described above, the team looked at two proteins, ABHD5 and ATGL. ABHD5, one of the proteins that directs the breakdown of fats, was reduced in obese and sedentary mice, while in the strength training group, ABHD5 levels were normal and interactions with ATGL, an enzyme that breaks down fats, were also increased. When the suppression of the Scd1 gene, which plays a role in fat production, was added in mice that exercised, the researchers say they have evidence that strength training, combined with aerobic exercise, can work to promote weight loss.

The research has been published. This article was verified by Fiona MacDonald (link) and edited by MacDonald (link). We are proud of our process, but we are only human; if you spot an error, please let us know (link).