You can keep strength while cutting
Medium confidence
Eating at a calorie deficit (a cut) slows how fast muscle grows. Strength holds up better: in pooled trials, strength gains during a deficit were not clearly smaller than at energy balance. Keep training hard and you can usually maintain strength while cutting, and many people still get stronger.
Why it works
A lot of strength comes from neuromuscular learning: your nervous system getting better at firing the muscle you already have. That skill grows with practice, not extra food, so a calorie deficit slows it far less than it slows building new muscle.
What it means in practice
If you're cutting, strength training is still worth doing. Getting weaker is not a given. Keep your loads heavy and your form clean, and expect muscle size to stall rather than grow. That stall is normal, not a sign the work is wasted.
The evidence
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Lifting in an energy deficit blunted lean-mass gains compared with lifting in energy balance, yet strength gains held up about the same in both conditions. The meta-regression put the tipping point near 500 kcal/day: past that, lean mass stopped growing. If you're trying to add muscle, skip long stretches in a large deficit. If you're preserving muscle while losing weight, keep the deficit below roughly 500 kcal/day.
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Pooling 30 randomized trials and 1,416 adults with overweight or obesity, resistance training produced large strength gains (SMD 1.39, 95% CI 1.05-1.73) and moderate gains in physical function (SMD 0.67, 95% CI 0.25-1.08). Effects on muscle power stayed uncertain. Concurrent caloric restriction did not reduce the strength gains, though it may attenuate the physical-function gains.
n=1416
Why we call confidence medium
A meta-analysis of randomized trials (Murphy 2021) found energy deficits impaired lean-mass gains (ES -0.57) while strength gains were not significantly different from energy balance (ES -0.31, p = 0.28), and a deficit of about 500 kcal a day was enough to block lean-mass gains. A meta-analysis of 30 trials in overweight and obese adults (Orange 2020) found calorie restriction did not change strength gains from resistance training. Neither study tested protein intake, and data on athletes specifically are thinner, which is why this sits at medium confidence.
Where it applies
Adults doing resistance training during a moderate calorie deficit (about 500 kcal a day or less). Evidence comes from general and overweight or obese adults, not runners specifically.
Does not apply to: severe or prolonged deficits, where strength and performance do decline; deficits above about 500 kcal a day when the goal is keeping lean mass.
Last reviewed Oct 14, 2026. See how we score.