Results of the study indicated that rice protein isolate administration post resistance exercise decreases fat-mass and increases lean body mass, skeletal muscle hypertrophy, power and strength comparable to whey protein isolate.
The study’s findings have been submitted to Nutrition & Metabolism and were presented recently by Dr Ralf Jaeger from Wisconsin-based Increnovo LLC, who collaborated on the research with Dr. Jacob Wilson from The University of Tampa.
The rice protein the researchers chose for the study was Growing Naturals’ Organic Rice Protein made with Axiom Food’s Oryzatein.
David Janow, Axiom’s CEO and President, and owner of Growing Naturals, told NutraIngredients-USA: “The effects were not just similar between rice and whey, they were identical.”
The amino acid profile for rice protein and whey protein is very similar, he said, with differences of 1-3% in some of the amino acids. Rice protein is even better for arginine and glutamine, he noted, while whey is better for the branched chain amino acids (BCAA).
Dr Jaeger added: "From the amino acid analysis you can see that rice protein isolate is not a 'complete' protein (Lysine content is too low) and that THE sports amino acid leucine is lower in rice protein isolate compared to whey protein isolate (8% vs. 11.5%). However, in combination with resistance training at 48g both show the absolute identical results on recovery, body composition (lean body mass, fat free mass, muscle hypertrophy), and ultimately on strength and power (that's the only real thing athletes care about). Both resulted in massive gains."
“There is a high correlation to whey and I knew that from a long time ago," Janow told us. "What the new study showed was that the difference in amino acid values is not enough to change the effects, compared to whey.”
“This is a groundbreaking study. Having clinical trial support behind us gives us credibility.”
Dr Jaeger and Dr Wilson recruited 24 healthy, college-aged, resistance-trained participants with an average age of 21 to participate in their double-blind, placebo-controlled clinical trial.
The participants were randomly assigned to receive either 48g of rice or whey protein isolate immediately following training on training days only for eight weeks.
Results showed that the rice protein isolate (RPI) was comparable to whey for fat-mass reduction, and increases in lean body mass, skeletal muscle hypertrophy, power, and strength.
“In the past, studies have shown that the combination of resistance exercise with consumption of animal-derived protein (such as whey, casein, eggs, meat) has had a different effect on muscle growth than when resistance exercise was paired with plant-based protein such soy,” said Dr. Jaeger.
“We found that rice protein isolate administration post resistance exercise decreases fat-mass and increases lean body mass, skeletal muscle hypertrophy, power and strength comparable to whey protein isolate.”
Sharing the top spot on the sports nutrition podium
Whey dominates the sports nutrition category, and the results of the new study mean that rice protein isolate is “not taking whey’s trophy away”, said Janow, “but we now share that trophy”.
The rice protein isolate is currently only used in Growing Naturals’ Organic Rice Protein, and Janow is now expecting significant interest from the industry. Price is also a very addition to the situation: Axiom’s rice protein isolate currently costs $7-9/kg, so is between 25 and 33% less expensive than whey protein isolate, he noted.
Janow said that protein works for everyone, but it works for sports nutrition “really, really well”.
The company has experience triple digit growth for the last three years, he said. “The company did about $24 last year, and this year we’re set to do $50-60 million. We’re not dabbling in this.”
While protein blends are gaining traction in the sports nutrition category, Janow said he was “not into blends, but more into a focused one-off product”.
The company has just filed a patent for the application of whole grain brown rice protein for sports nutrition, he added.
Dr Jaeger will also present these results at the 36th Annual National Conference of the National Strength and Conditioning Association (NSCA), July 10-13, 2013 in Las Vegas, NV, and at the 10th Annual Conference and Expo of the International Society of Sports Nutrition (ISSN) in Colorado Springs, CO, June 14-15, 2013