You spend hours in the gym building stronger muscles, but are you giving your tendons the same attention? Your tendons are the critical link that transfers force from muscle to bone. Stronger, stiffer tendons mean more explosive power and a lower risk of injury.
A new study published in Experimental Physiology investigated a simple way to supercharge your tendon adaptations from training: adding collagen.
The Study: Targeting Tendons in Pro Athletes
Researchers wanted to see if combining high-intensity resistance training with collagen supplementation could improve tendon properties in a group of athletes who need them most: professional female soccer players.
Here’s the setup:
- Who: Professional female soccer players during their 10-week pre-season.
- The Training: A demanding schedule including high-intensity lower-limb resistance training (think split squats at 75-90% of 1-RM), plyometrics, and regular on-pitch soccer practice.
- The Groups: The athletes were split into two groups. Both groups performed the exact same training, but one group consumed a supplement immediately before three training sessions per week.
- Collagen (COL) Group: Drank 30g of hydrolyzed collagen with 500mg of Vitamin C.
- Placebo (PLA) Group: Drank a calorie-matched carbohydrate drink with 500mg of Vitamin C.
The researchers measured the athletes' patellar (kneecap) tendon properties, muscle strength, and muscle size before and after the 10-week intervention.
The Main Event: Collagen Supercharged Tendon Stiffness
The results were striking. While both groups benefited from the tough pre-season training, the collagen group saw significantly better improvements in their tendon quality.
After 10 weeks, the collagen group experienced much greater increases in:
- Tendon Stiffness: +15.4% for the collagen group vs. +4.6% for the placebo group.
- Young's Modulus (a measure of material stiffness): +14.2% for the collagen group vs. +3.4% for the placebo group.
This is the key takeaway. The training itself made tendons stiffer, but adding 30g of collagen beforehand more than tripled the effect. A stiffer tendon can handle greater loads and transmit force more efficiently, which is a huge win for performance and injury resilience.
What About Tendon and Muscle Size?
Interestingly, the study found no significant differences between the groups when it came to muscle or tendon growth.
- Tendon Size: Both groups saw a small increase in patellar tendon cross-sectional area (CSA) from the training, but collagen didn't provide an extra boost.
- Muscle Size & Strength: Neither group saw significant changes in quad muscle thickness or maximal strength.
This isn't surprising. The authors noted that these were already highly trained professional athletes, so their potential for rapid strength and size gains was limited. Furthermore, collagen is primarily composed of amino acids like glycine and proline, which are crucial for connective tissue, but it lacks the full spectrum of essential amino acids needed to maximize muscle protein synthesis.
Your Coaching Takeaways
This study provides a clear, practical protocol for athletes and lifters looking to enhance their connective tissue health.
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Timing is Key: The athletes consumed their supplement immediately before training. This timing is thought to deliver the necessary amino acid building blocks to the tendon right when the training stimulus increases blood flow and synthesis activity.
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The Dose Matters: The study used a 30g dose of hydrolyzed collagen. Previous research has suggested that this dose is more effective for stimulating collagen synthesis than smaller doses like 15g.
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Don't Forget Vitamin C: Vitamin C is a critical cofactor in the process of building new collagen. The study included 500mg of Vitamin C with each supplement.
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Training is the Trigger: Collagen isn't a magic powder. The high-intensity resistance and plyometric training was the non-negotiable stimulus that kicked off the adaptation process. The supplement simply amplified the body's response to that training.
Important Considerations
As with any study, it's important to note the limitations. The final sample size was small (6 in the collagen group, 5 in the placebo group) due to injuries and other withdrawals. However, the researchers performed a power analysis and found their study was sufficiently powered to detect the large effects they observed in tendon stiffness.
These findings are specific to professional female athletes, but they align with other research in different populations, giving us confidence in the results. The takeaway remains the same: if you want to build more resilient tendons, combining targeted training with pre-exercise collagen and vitamin C is a science-backed strategy.
The Bottom Line
For athletes, lifters, and anyone looking to improve their joint and tendon health, this study offers a powerful formula: combine high-intensity training with 30g of hydrolyzed collagen and 500mg of Vitamin C taken just before your session. It won't replace hard work, but it can significantly enhance the quality and resilience of your most important connective tissues.
Reference:
Lee, J., Robshaw, D. C., & Erskine, R. M. (2024). High‐intensity resistance training and collagen supplementation improve patellar tendon adaptations in professional female soccer athletes. Experimental Physiology. https://pubmed.ncbi.nlm.nih.gov/39207908/