Fasting didn't blunt gains from lifting in 11 trials

Intermittent fasting and lifting are frequently stacked together by people trying to lose fat without losing muscle, and the obvious worry is that a compressed eating window undermines the training. Previous reviews mostly examined body composition and metabolic markers, which tells you little about whether the barbell moves. Strength, muscular endurance, muscle size and explosive performance are the outcomes lifters actually train for, and they had not been pooled specifically. This analysis set out to compare fasting plus resistance training against resistance training alone on exactly those adaptations.

The authors searched PubMed, Web of Science and SPORTDiscus to 10 March 2026 for peer-reviewed, English-language randomised parallel-group or crossover trials. Eligible studies compared intermittent fasting plus resistance training with resistance training alone for at least 4 weeks in generally healthy participants. Eleven studies with 303 participants were included, with interventions running from 4 weeks up to 12 months and most using time-restricted eating or feeding. Training programmes were generally matched between arms. Risk of bias was assessed with the Cochrane Risk of Bias 2 tool, and Hedges' g values from between-group change scores were pooled using multilevel random-effects models with cluster-robust variance estimation.

Overall, adding intermittent fasting to resistance training produced adaptations broadly similar to resistance training alone, with a pooled effect of g = 0.09 and a 95% confidence interval from −0.23 to 0.40. No clear differences emerged for maximal strength, local muscular endurance, site-specific hypertrophy-related outcomes or explosive and high-speed performance. Body-region subgroup analyses also showed no clear separation between the two approaches. Participants were mostly young adults with varied training status and body-composition profiles, which the authors flag as a source of variability. The interval spanning zero in both directions means a modest advantage or disadvantage cannot be ruled out.

This extends the fasting literature from body composition and metabolic outcomes into the performance adaptations that matter to people who lift. It is consistent with the view that total nutritional intake and the training stimulus itself dominate, and that meal timing is a smaller lever, but the authors are careful to frame it as an absence of clear harm rather than proof of equivalence. Their conclusion is conditional: it holds when the training programme and nutritional support are reasonably maintained. Whether the picture changes in older lifters, in advanced trainees, or under an aggressive energy deficit remains open.

If a restricted eating window suits your routine, this pooled evidence gives little reason to expect it to sabotage strength or muscle-related outcomes when training and nutrition are otherwise looked after. Equally, there is no sign here that fasting adds anything to the adaptations themselves. With 11 trials and 303 participants, the analysis is explicitly exploratory, and the confidence interval leaves room for small effects in either direction. The practical takeaway is that the eating window looks like a preference question rather than a performance one.