Animal Study: Seven Days of Strength Training Shrank Fat Cells in Mice
Seven strength-training sessions shrank fat cells in the abdominal cavity of obese male mice and partly restarted the disrupted fat breakdown inside those cells, although body weight did not change. The findings suggest that some effects of strength training begin before weight loss becomes visible.
1. What the Research Says
Only male mice and only the fat tissue around the intestines were studied; the researchers measured fat mass, fat-cell size and proteins of fat breakdown, while body weight stayed the same. The work does not show whether seven training sessions have the same effect in humans.
2. How It Fits Earlier Research
In humans, the picture is mixed: a 2012 meta-analysis found no clear reduction in abdominal fat from strength training alone, but did with aerobic training. A larger 2021 meta-analysis of 34 studies, by contrast, found a small but clear reduction in abdominal fat from strength training. The mouse study offers a possible mechanism for this. A systematic review and meta-analysis of the effect of aerobic vs. resistance exercise training on visceral… (2012) · Effect of resistance training with and without caloric restriction on visceral fat: A systemic review and meta-analysis. (2021)
3. Source
ScienceDaily: Just 7 days of strength training started shrinking fat cells in mice (2026-10-08)
Full evidence overview: Strength training
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