Researchers looked at 78 different studies involving nearly 5,000 people to figure out which protein supplements work best when combined with strength training. They tested 13 different types of protein supplements to see which ones helped people build muscle strength and muscle mass. The big winner? Collagen came out on top for both building strength and muscle mass, followed by whey protein. Surprisingly, most other protein supplements didn’t show any real advantage over a placebo (a fake supplement). This research gives people who lift weights a clear answer about which supplements are actually worth their money.

The Quick Take

  • What they studied: Which types of protein supplements help people build muscle strength and muscle mass when they do resistance training (like lifting weights)?
  • Who participated: Nearly 5,000 healthy adults from 78 different research studies who were doing strength training exercises. The studies tested 13 different protein supplements plus placebo and control groups.
  • Key finding: Collagen was the most effective supplement for building both strength and muscle mass, followed by whey protein. All other supplements tested didn’t show meaningful benefits compared to placebo.
  • What it means for you: If you’re doing strength training and considering protein supplements, collagen and whey protein appear to be your best choices. However, this doesn’t mean you need supplements—proper training and regular diet matter most. Talk to your doctor before starting any supplement.

The Research Details

This was a network meta-analysis, which is like a super-study that combines results from many smaller studies to find patterns. Researchers searched three major scientific databases (PubMed, Scopus, and Embase) for all studies published up to May 2024 that tested protein supplements combined with strength training. They included 78 studies with nearly 5,000 total participants.

The researchers looked at two main outcomes: how much strength people gained and how much muscle mass (fat-free mass) they built. They compared 13 different types of protein supplements against placebo (fake supplement) and control groups (no supplement). This approach is powerful because it lets researchers compare many different supplements at once, even if no single study tested all of them head-to-head.

Instead of relying on one or two studies, this approach combines evidence from many studies to give a clearer picture of what actually works. This is especially important for supplements because individual studies can have different results based on how they’re designed. By looking at all the evidence together, researchers can identify which supplements truly make a difference and which ones don’t.

This study is a systematic review and network meta-analysis, which is considered high-quality evidence. The researchers searched multiple databases and included 78 studies, which is a large number. They looked at randomized controlled trials, which are the gold standard for testing supplements. However, the quality depends on the individual studies included—some may have been better designed than others. The fact that most supplements showed no benefit suggests the researchers weren’t biased toward finding positive results.

What the Results Show

For muscle strength, collagen was clearly the winner. People taking collagen with strength training showed significantly better strength gains compared to those taking a placebo. The effect was moderate in size. Whey protein came in second place, also showing real benefits for strength, though smaller than collagen.

For building muscle mass (fat-free mass), the results were similar. Collagen again showed the strongest effect, with whey protein in second place. Interestingly, collagen’s benefit for muscle mass was even more impressive than its benefit for strength.

All the other supplements tested—including casein, soy, pea, hemp, and several others—did not show any statistically significant advantage over placebo. This means the differences could have been due to chance rather than the supplements actually working.

The research also revealed that collagen’s advantage over whey protein was consistent across both outcomes measured. This suggests collagen may have unique properties that make it particularly effective for strength training. The researchers ranked all supplements using a scoring system (SUCRA), which showed collagen at 88% confidence for strength and 60% for muscle mass, while whey protein was at 64% and 60% respectively.

Previous research has generally supported the idea that protein supplements help with strength training, but this is the first comprehensive comparison of so many different types. Earlier studies often focused on just whey protein or casein. This research confirms that whey protein works, but it also introduces collagen as a potentially superior option—something that hasn’t been as thoroughly studied before. The finding that most other supplements don’t work better than placebo contradicts some marketing claims in the supplement industry.

The study has several important limitations. First, the quality of the 78 included studies likely varied—some were probably better designed than others. Second, the studies may have used different doses of supplements, different training programs, and different ways of measuring results, which could affect the findings. Third, most studies were relatively short-term, so we don’t know if these benefits continue over months or years. Fourth, the studies mostly included healthy young adults, so results might be different for older people or those with health conditions. Finally, the research doesn’t explain why collagen works better than other supplements—just that it does.

The Bottom Line

If you’re doing strength training and want to use a protein supplement, collagen or whey protein appear to be your best choices based on current evidence (moderate confidence). However, remember that supplements work best when combined with proper training and good nutrition. You don’t need supplements to build muscle—consistent training and adequate protein from food (like chicken, eggs, beans, or yogurt) can work just fine. If you do choose to supplement, start with a reasonable dose and give it at least 8-12 weeks to see results.

This research is most relevant for healthy adults doing regular strength training who are considering protein supplements. If you’re already getting enough protein from food, supplements may not add much benefit. People with kidney disease, liver disease, or certain allergies should talk to their doctor before taking any supplement. Pregnant or breastfeeding women should also consult their healthcare provider. If you’re taking medications, check with your doctor about potential interactions.

Most of the studies included in this analysis lasted 8-12 weeks. You should expect to see noticeable strength and muscle gains within 4-8 weeks if the supplement is going to work for you, but give it at least 12 weeks for full effects. Remember that genetics, training consistency, sleep, and overall diet matter just as much as supplements.

Want to Apply This Research?

  • Track weekly strength gains (weight lifted or reps completed) and monthly body composition changes (muscle mass percentage if available, or how clothes fit). Log supplement intake daily to correlate with performance improvements.
  • If using a protein supplement, set a daily reminder to take it at the same time each day (ideally within 2 hours after strength training). Log your workout performance metrics weekly to see if you’re making progress.
  • Create a monthly check-in to review strength progress and any changes in how you feel or look. Track consistency with both supplement use and training. After 12 weeks, assess whether the supplement is worth continuing based on your actual results versus your goals.

This research summary is for educational purposes only and should not replace professional medical advice. Before starting any new supplement, especially if you have existing health conditions, take medications, or are pregnant or breastfeeding, consult with your doctor or a registered dietitian. Supplements are not regulated the same way as medications, and individual results vary. This analysis represents current evidence but new research may change these findings. Always combine supplements with proper training, adequate sleep, and a balanced diet for best results.