Just 7 Days of Exercise Begins to Shrink Fat Cells in Mice

Author / Editor: Barış Özdemir•12 October 2026

✓ Editorially Verified

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 studying the effects of diet, exercise, or other factors to separate these weight loss effects from what they are trying to measure. The researchers wanted to clarify the effects of strength training on fat cells before mice began to lose weight by looking at the visceral (inner) fat around the organs of the mice before they lost weight. link

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

In addition to the benefits described above, the team also 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 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, along 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).