Exercise affects visceral fat in mice

Brazilian researchers observed changes in visceral fat in obese mice after a seven-day weight training regimen, without any weight loss. The study, conducted by a team from the University of Campinas and published on June 23, 2026, involved making the mice climb a 70-centimeter staircase with a fixed load attached to their tails.

Exercise protocol details

Each session included 20 climbs, interrupted by pauses of 60 to 90 seconds. The load reached 70% of each animal's maximum capacity, and seven sessions were carried out over two weeks. This intense regimen aimed to simulate resistance training in humans.

Visceral fat and its effects

The targeted tissue was visceral fat, the fat that surrounds the intestines. In excess, this visceral fat releases inflammatory substances into the bloodstream and disrupts metabolism. The challenge was to observe its transformations before any weight loss could skew the measurements.

Results of the exercise regimen

At the end of the protocol, the mice subjected to exercise weighed the same as the sedentary ones, but their visceral fat had decreased in volume and their adipocytes had shrunk. This shrinkage usually indicates a healthier metabolic tissue. The signals promoting lipid accumulation were less active in the exercising group.

Molecular changes due to exercise

At the molecular level, exercise altered the activity of several proteins related to lipid metabolism. In sedentary mice, the levels of ABHD5, among other proteins, were different compared to the exercising group. These changes suggest that physical activity can influence metabolic processes independently of weight loss.