Impact of Vegan Diets on Resistance Exercise-Mediated Myofibrillar Protein Synthesis in Healthy Young Males and Females: A Randomized Controlled Trial.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 40197715 · doi:10.1249/MSS.0000000000003725
What was done
Forty healthy, physically active adults (28 males, 12 females; aged 25 ± 4 yr; BMI 24.1 ± 2.1 kg·m⁻²) completed a 9-day randomized controlled trial with controlled feeding and resistance training. Participants consumed a weight-maintenance diet providing 1.1–1.2 g·kg⁻¹·d⁻¹ of protein from either an omnivorous (OMN) or vegan (VGN) dietary pattern, with either an unbalanced protein distribution (UB: 10%, 30%, and 60% of daily protein across 3 meals) or a balanced distribution (B: 20% across 5 eating occasions). Participants completed whole-body resistance exercise 3 times during the trial while ingesting deuterated water (D₂O) to assess daily myofibrillar protein synthesis rates.
What was found
Percent kilocalories from carbohydrate was higher in the OMN compared with VGN groups (P = 0.045), but no other dietary intake differences occurred. Daily myofibrillar protein synthesis rates did not differ significantly between groups (all P > 0.05): - OMN-UB: 3.04% ± 1.85%·d⁻¹ - OMN-B: 2.43% ± 1.21%·d⁻¹ - VGN-UB: 2.52% ± 1.77%·d⁻¹ - VGN-B: 2.49% ± 1.56%·d⁻¹
Why it matters
This study demonstrates that an exclusively plant-based vegan diet supports daily myofibrillar protein synthesis rates comparably to an omnivorous diet at moderate protein intakes (1.1–1.2 g·kg⁻¹·d⁻¹). It also indicates that spreading protein evenly across meals does not enhance daily muscle protein synthesis compared to an uneven distribution during short-term training.
Limits
The intervention was short (9 days, 3 training sessions) and measured acute daily synthetic rates rather than long-term muscle hypertrophy or strength outcomes. The sample size (n = 40 total, ~10 per group) showed wide variance across groups, which could obscure small effect sizes. The protein intake investigated (1.1–1.2 g·kg⁻¹·d⁻¹) is lower than typical recommendations for resistance training athletes (1.6–2.2 g·kg⁻¹·d⁻¹).
Cited by
- supports A study by Nicholas Burd comparing vegan and omnivorous diets with even versus uneven protein distribution (10% at breakfast, 30% at lunch, 60% at dinner vs. five even meals) found no difference in daily muscle protein synthesis rates across groups.