Monday, June 24, 2013

Is Rice the New Whey to Go? Study Shows, Rice and Whey Protein Equally Support Mass & Strength Gains + Fat Loss in Resistance Trained College Aged Men

Is rice the new whey to go? Or just something for the average vegan who realizes that he cannot go without protein?
While I personally considered the study on phosphatidic acid (yesterday's news) most interesting, there were many other presentations on the ISSN conference that are worth mentioning (note: my buddy Sean Casey is about to write a summary of his stay there, I'll let you know on Facebook, when he is done). The full-text papers are however only available for one of the studies, which has likewise been conducted by Joy et el. (see PA study). The fulltext just appeared on the website of the Nutrition Journal (Joy. 2013) and is also the topic of today's SuppVersity article that revolves - once again - around the question, whether whey really is the whey (all typos intended) to go.

Is there any other way than whey?

The study was conducted with 24 college-aged, resistance trained males (21.3 ± 1.9 years, 76.08 ± 5.6 kg, 177.8 ± 12.3 cm) who had trained at least three times per week for the past 6 months. The guys were randomly and equally divided into two groups, consuming either 48 g of rice or whey protein
isolate (isocaloric and isonitrogenous)
right after the workout.
Figure 1: Amino acid profile of the rice and whey protein isolate (Joy. 2013)
"The program  was designed to train all major muscle groups using mostly compound movements for the  upper and lower body. The programmed, non-linear training split was divided into  hypertrophy days consisting of 8–12 RM loads for 3 sets, with 60–120 seconds rest and  strength days consisting of 2 to 5 RM loads for 3 sets for all exercises except the leg press  and bench press which received 5 total sets. Weights were progressively increased by 2–5%  when the prescribed repetitions could be completed. All training sessions were closely monitored by the researchers to ensure effort and intensity were maximal each training session." (Joy. 2013)
The subjects s trained 3 days per week for 8 weeks as a part of a daily undulating periodized resistance-training program (see quotation. above). Ratings of perceived recovery, soreness, and readiness to train were recorded prior to and following the first training session. The changes muscle thickness was determined by ultrasonography and DEXA scans were used to assess the body composition.

Put your prejudices aside, results are the only thing that counts

Moreover bench press and leg press for upper and lower body strength were recorded during weeks 0, 4, and 8 and statistically analyzed, when the study was over.
Figure 2: Bench pres, leg press strength and peak power before, during  and after the study (Joy. 2013)
As you can see the strength increases did not differs significantly when you compare the rice to the whey protein. Against that background it is actually not very surprising to see that the same was the case for the change in body composition, I plotted in figure 3.
Figure 3: Baseline and post study body composition and muscle size (Joy. 2013)
If we take another look at the amino acid profile in figure 1, it does yet become evident that the effects could have been different, if the subjects stuck to only 50% of the amount of protein they ingested in the study at hand.
Figure 4: Theoretical model for protein dose and the anabolic response (adapted from Joy. 2013)
"In the present study, the combined muscle thickness of the VI and VL increased in both the rice protein (0.2 cm) and whey protein (0.5 cm) conditions. Lean body mass increased in the rice protein condition by 2.5 kg, and it also increased in the whey protein condition by 3.2 kg. Combined bench press and leg press 1-RM strength increased in the rice protein condition by 76.4 kg and in the whey protein condition by 89.5 kg. However, no significant differences were observed between the two conditions for any measure. The collective findings of our study and others suggests that as the amount of protein consumed increases, the importance of the relative leucine content of the protein diminishes" (see figure 4; Joy. 2013).
Overall, the study at hand does therefore provide reliable evidence that people with dairy intolerance fair pretty well with a rice protein - as long as they make up for the 30% lower leucine content.

Rice protein can be a valuable replacement for whey. Just remember, you cannot live on rice alone, because you would be running the risk of not getting adequate lysine, which would heavily compromise the nitrogen balance increase anxiety, impaired catecholamine release, etc. (cf. Albanese. 1941; Smriga. 2000, 2002, 2003). As part of a regular diet, rice proteins do yet in fact appear to be a viable (yet higher to dose) alternative to whey protein, which has be the way been shown to help with blood lipid management, only recently (Yang. 2013).

  • Albanese, Holt LE, Brum-Back JE, Hayes M, Kajdi C, Wangerin DM. Nitrogen Balance in Experimental Lysine Deficiency in Man. Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, NY). Royal Society of Medicine. 1941; 48(3): 728-730. 
  • Joy JM, Lowery RP, Wilson JM, Purpura M, De Souza EO, Wilson SM, Kalman DS, Dudeck JE, Jäger R. The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance. Nutr J. 2013 Jun 20;12(1):86.
  • Smriga M, Mori M, Torii K. Circadian release of hypothalamic norepinephrine in rats in vivo is depressed during early L-lysine deficiency. J Nutr. 2000 Jun;130(6):1641-3. 
  • Smriga M, Kameishi M, Uneyama H, Torii K. Dietary L-lysine deficiency increases stress-induced anxiety and fecal excretion in rats. J Nutr. 2002 Dec;132(12):3744-6.
  • Smriga M, Torii K. L-Lysine acts like a partial serotonin receptor 4 antagonist and inhibits serotonin-mediated intestinal pathologies and anxiety in rats. Proc Natl Acad Sci U S A. 2003 Dec 23;100(26):15370-5.
  • Yang L, Han G, Liu QH, Wu Q, He HJ, Cheng CZ, Duan YJ. Rice protein exerts a hypocholesterolemic effect through regulating cholesterol metabolism-related gene expression and enzyme activity in adult rats fed a cholesterol-enriched diet. Int J Food Sci Nutr. 2013 Jun 14.