The latest superfood rippling through the sports world isn't derived from an obscure Amazonian berry or a Himalayan tree bark. Instead, it's a holdout from 1970s dinner parties.
Earlier this year, a team of researchers published data suggesting that daily doses of gelatin – the magic ingredient that made Jell-O salads so beguiling – combined with ultrashort bouts of exercise could help strengthen tendons, ligaments, bones and cartilage. While the results remain preliminary, professional athletes looking to speed their rehab from injury have eagerly seized on the findings – and the early buzz is encouraging.
The idea of using gelatin emerged from a long series of studies led by Keith Baar, a Burlington, Ont.-raised scientist who heads the Functional Molecular Biology Lab at the University of California, Davis. Baar and his colleagues developed "engineered ligaments," lab-grown tissues that can be stretched to their breaking point (and beyond) to investigate which factors affect the risk of injury.
For many years, tendons and ligaments were considered to be a mostly inert collection of ropes and elastic bands holding your bones and muscles together. It's now clear, though, that you can help them become stronger and more resilient by manipulating the collagen that forms the backbone of these tissues.
Exercise is one key approach – but connective tissue doesn't respond like muscles, which can benefit from hours of gruelling exercise.
"We've been training for heart and muscles for years," Baar says. "But training bone and ligament is totally different."
Tendons, ligaments and bones get all the stimulus they can handle from five to 10 minutes of exercise; after that, they derive no further benefit until they've had a chance to rest for about six hours.
What you eat can also make a difference. Baar found that a combination of vitamin C and an amino acid called proline helped increase how much collagen was produced in connective tissues. "When I went to the internet to look for proline-rich foods," he recalls, "gelatin was by far the most concentrated source."
Working with Gregory Shaw of the Australian Institute of Sport and other collaborators, Baar put these elements together in a double-blinded trial of eight men, published in the American Journal of Clinical Nutrition. The subjects did six minutes of rope-skipping three times a day for three days, with at least six hours of rest between sessions. An hour before each session, they drank a mix of collagen and vitamin C.
The results showed that simply jumping rope three times a day doubled rates of collagen synthesis. Adding five grams of gelatin before the mini-workouts didn't make much difference, but adding 15 grams doubled collagen synthesis again, for an overall four-fold increase.
These indirect measurements of collagen synthesis were based on blood tests, which mostly revealed activity in the subjects' bones. But, in a vampiric twist, when blood from subjects who had taken gelatin was applied to engineered ligaments in Baar's lab, they too showed increased collagen content compared with ligaments treated with Jell-O-free blood.
It's a remarkable demonstration that supposedly "inert" tissues really can adapt if you understand how to feed and exercise them. But is it ready for real-world use? "We have only anecdotal evidence so far," Baar acknowledges, "mostly on return-to-play."
He cites individual success stories ranging from Australian national-team rugby players making rapid returns from ACL ruptures, to a pro basketball player with a tendon injury in his knee, to his daughter's soccer teammates treating heel pain.
Earlier this month, Baar spent a week in Vancouver huddling with representatives of Canadian Sport Institutes from coast to coast, brainstorming the practical realities of using this approach. One challenge, one of the sports nutritionists pointed out: 15 grams is a lot of gelatin. You'd need about eight servings of standard Jell-O, which would deliver 150 grams of sugar. Instead, you're better off mixing about 1.5 tablespoons of pure gelatin into a drink.
If you're rehabbing from an injury, start very light exercises – five to 10 minutes with at least six hours break – within one to two days of injury, Baar suggests.
The type of exercise should target the tissue you're concerned about. Skipping or hopping stimulates bone growth, so it might be the right choice if you've had stress fractures. If you've got a sore Achilles tendon, stand on the toe with the sore Achilles and hold for 30 seconds, take a 30-second break, then repeat three to five times. If you've got a shoulder problem, work the shoulders.
Not everyone is convinced, Baar notes. Jill Cook, a prominent tendon expert in Australia, worries that the protocol will trigger only superficial collagen growth without addressing damage at the core of the tendon.
Ultimately, it will require careful, well-designed clinical studies to figure out if gelatin plus mini-workouts make a measurable difference to injury rates and rehab time. But for athletes such as Matt Laye, an ultrarunner and exercise scientist at the College of Idaho who is currently recovering from surgery to repair damaged cartilage, the pros of following a promising but unproven plan outweigh the cons.
"I have developed a plan that I think gives me at least a better chance of improving my long-term outcome," he wrote in a recent blog post explaining his use of gelatin. "That placebo alone is worth the trouble of researching and implementing such a plan."
Alex Hutchinson's latest book is Which Comes First, Cardio or Weights? Follow him on Twitter @sweatscience