Another interesting study on protein
Protein timing is a popular dietary strategy designed to optimize the adaptive response to exercise. The strategy involves consuming protein in and around a training session in an effort to facilitate muscular repair and remodeling, and thereby ...
pmc.ncbi.nlm.nih.gov
The study titled "The effect of protein timing on muscle strength and hypertrophy: a meta-analysis" (PMCID: PMC3879660, PMID: 24299050), published in the *Journal of the International Society of Sports Nutrition* on December 3, 2013, investigated whether consuming protein around exercise sessions (protein timing) enhances muscle strength and hypertrophy compared to consuming protein at other times. The researchers, Brad Jon Schoenfeld, Alan Albert Aragon, and James W. Krieger, conducted a meta-analysis of randomized controlled trials to assess this popular dietary strategy.
### Key Findings:
1. **Muscle Hypertrophy**: The meta-analysis found no significant effect of protein timing on muscle hypertrophy. When protein was consumed close to resistance exercise sessions (within about an hour before or after), there was no statistically meaningful increase in muscle growth compared to consuming protein at other times of the day. The effect size was small and not significant (p = 0.74).
2. **Muscle Strength**: For muscle strength, the results showed a small, statistically significant benefit of protein timing (p = 0.05). However, this effect was modest and primarily observed in lower-body strength outcomes (e.g., leg press). Upper-body strength (e.g., bench press) showed no significant difference based on timing.
3. **Study Characteristics**: The analysis included 23 studies with a total of 525 participants. The studies varied in terms of training status (trained vs. untrained individuals), duration (ranging from 4 to 14 weeks), and protein intake (both total daily protein and supplemental protein doses). Most studies used whey protein supplements.
4. **Limitations**: The researchers noted several limitations:
- The small number of studies and participants limited the statistical power.
- Heterogeneity in study designs (e.g., timing windows, protein doses, and training protocols) made it challenging to draw definitive conclusions.
- Many studies had methodological flaws, such as lack of dietary control or small sample sizes.
5. **Practical Implications**: The findings suggest that protein timing may have a minor impact on strength gains but does not significantly affect muscle hypertrophy. The authors emphasized that total daily protein intake and consistent resistance training are likely more critical for optimizing muscle adaptations than the specific timing of protein consumption around workouts.
### Conclusion:
The meta-analysis concluded that while protein timing might offer a slight edge for strength improvements, particularly in the lower body, it does not appear to be a major factor in muscle hypertrophy. The practical significance of timing seems limited, and individuals aiming to maximize muscle gains should prioritize overall protein intake and training consistency over strict timing protocols. Further research with larger, well-controlled studies was recommended to clarify these effects.
pubmed.ncbi.nlm.nih.gov
