Research update: Collagen and soft tissue injuries

Speaking at the Academy of Nutrition and Dietetics (AND) annual Food and Nutrition Conference and Exposition (FNCE), Keith Barr PhD and Dana Lis PhD RD, professors at the University of California at Davis, shared their latest research on Soft Tissue Health: Strategies for Injury Prevention and Recovery. Here are a few highlights from their talk:

Soft tissue injuries (ruptured tendons, torn ligaments, and muscle pulls) can be season-ending injuries. Preventing them from happening in the first place could save a lot of angst. Research suggests strength training (more so than stretching) reduces the incidence of these injuries.
Tendons and ligaments have a collagen-filled matrix. To heal tendon and ligament injuries, loading (stressing) them helps to increase collagen synthesis and make them stronger. For example, the anterior cruciate ligament (ACL) gets thicker (i.e., stronger) during a training season.
Unlike muscles, the tendons and ligaments get nourished without blood flow to provide nutrients. Rather, fluid in connective tissue gets squeezed out when the muscle stretches during exercise; nourishing fluid then gets sucked in when the muscle relaxes. Consuming a collagen supplement 30 to 60 minutes before exercise assures having collagen-building amino acids circulating around the damaged tissue. This has been shown to enhance healing.
Athletes in sports that include explosive movements (basketball, track and field, soccer) might want to take collagen supplements prophylactically, to create tissues that are more injury-resistant. Doing so may also enhance their performance. One study suggested hydrolyzed collagen during training also improved explosive performance compared to a placebo.
While research is limited (and commercial collagen products are exploding), hydrolyzed collagen, collagen peptides, and yes, Knox gelatin all offer the amino acid glycine, needed to heal these tissues. Not all collagen supplements are created equal. Bone broth, for example, has low levels of glycine. Hydrolyzed collagen seems to be absorbed better than gelatin and tends to be more palatable.
Vitamin C is a co-factor needed to repair damaged tissue, so athletes should consume 50 mg vitamin C, such as in orange juice, along with the collagen supplement.
To date, research has not been done to determine if glycine-rich foods (meat, fish, and poultry, or in lessor amounts, soy, nuts and plant-proteins) are as effective as supplements. Would eating pre-exercise chicken + orange juice do the same job? Stay tuned.

Author

Sports Nutritionist Nancy Clark MS RD CSSD has a private practice in the Boston area, where she counsels both fitness exercisers and competitive athletes. She is author of the best-selling Nancy Clark’s Sports Nutrition Guidebook, now in it’s 6^th edition.