Summary of a review on effect of protein supplementation and resistance training on fat free mass gains, fat mass, and strength gains.
1387 healthy persons (361 females) aged 46 (±21) years.
Systematic review and meta-analysis of 35 randomized controlled trials.
Trials of at least 6 weeks duration, resistance training performed at least 2 times per week, no calorie restriction.
multi-ingredient protein supplement – "protein supplement with any additional ingredients added (eg, carbohydrate (CHO), Cr, β-hydroxy β-methylbutyrate (HMB), leucine (Leu), calcium, vit D and/or PUFAs)"
- body composition: total body mass, fat free mass, fat mass
- performance: 1-repetition maximum (1RM)
- Multi-ingredient protein supplementation with resistance training increased fat-free mass without increasing fat mass when compared to all the other conditions. Also, multi-ingredient protein supplementation with prolonged resistance training increased the upper body and lower body 1RMs comparing to all the other conditions.
- When multi-ingredient protein supplementation was compared with protein-only supplementation, fat mass increased without changes in total body mass, fat-free mass, upper or lower body 1RMs.
- There was significant heterogeneity in both comparisons for fat-free mass.
- When the differences in outcomes between young or older adults (>45 years) were investigated, the younger population observed no difference in upper body 1RM, and older adults no difference for lower 1RM.
- When trained persons were compared against untrained individuals, trained had no effect on fat-free mass or lower body 1RM, untrained had no difference in lower and upper body 1RMs but increased their fat-free mass.
- Protein supplements containing creatine (4 studies) increased on average fat-free mass by 1 kg, when compared with protein only supplements.
Take home message
O’Bryan KR, Doering TM, Morton RW, Coffey VG, Phillips SM, Cox GR. Do multi-ingredient protein supplements augment resistance training-induced gains in skeletal muscle mass and strength? A systematic review and meta-analysis of 35 trials. British journal of sports medicine. 2020 May 1;54(10):573-81.