From the NSCA's Performance Training Journal, this article provides evidence behind protein supplementation and its ability to augment gains in lean muscle mass.PTJ_11.6_Cover
Introduction
In today’s society, especially in the sporting world, the latest trend is to improve one’s athletic performance in order to become the biggest, fastest, and strongest, whether it is on the playing field and/or in a gym or weight room. Some individuals using resistance training may go to great lengths to reach their goals, including the illegal use of steroids. A more appropriate solution for increasing strength and lean muscle mass gained through resistance training is protein supplementation.
Appropriate Protein Supplementation
There are many protein supplements on the market, but few contain the proper ingredients necessary to satisfy an athlete’s optimal nutritional needs after resistance training. The highest quality proteins are the milk proteins, casein and whey (14).
Casein is slowly digested in the stomach, which allows a sustained elevation of the amino acids in the blood. Whey is digested much more rapidly than casein, and contains a large portion of the branched-chain amino acids, which are the most abundant amino acids in muscle tissue and critical for muscle building (14). Whey protein sources seem to be the most researched of the two, and there is good reason. There appears to be a positive correlation between increased lean muscle mass and increased muscular strength while performing resistance training with the consumption of whey protein supplements (3,4).
Hydrolyzed whey isolate, another type of whey protein, contains the highest concentration of the essential amino acids, including the branched-chain amino acids. In a study comparing whey isolate to casein during 10 weeks of resistance training, the participants supplementing whey isolate showed a greater increase in lean mass, a decrease in fat mass, along with an increase in strength when compared to those participants supplementing casein (6).
Not only is the type of protein important, but the amount of protein ingested is also important. Many times, individuals taking protein supplements will ingest too many grams causing the nitrogen balance in the body to be thrown off. Subsequently, the excess protein is excreted in the urine. The ingestion of excess protein supplements may place additional stress on the kidneys and liver, and may result in dehydration, calcium loss, and gastrointestinal problems (12). Thus, it is important to follow the guidelines in place for protein intake and supplementation. The average person needs approximately 0.8 g/kg bodyweight/day of protein to maintain muscle mass (3). Protein and amino acid requirements are higher for athletes in training (3). Resistance training athletes need 1.6 – 1.7 g/kg bodyweight/day while endurance athletes need approximately 1.2 – 1.4 g/kg bodyweight/day (5,11).
Therefore, it is important for athletes to be aware of the amount of protein needed by the body and not consume more protein in both dietary and supplemental form than is recommended.
Benefits of Protein Supplement Ingestion during Recovery
Research on resistance training has shown that protein consumption prior to resistance training can be effective. However, research on nutrient timing suggests protein consumption after resistance training may be more effective one hour after (5,13). Thus, the timing of protein supplementation is crucial. For the proper synthesis of protein, supplementation should take place during the recovery period after a bout of resistance training. Although, the body stays in an anabolic state for up to 48 hours after training, the one-hour window is most important for optimal synthesis. Anything after this time period will still be used by the body, but it will not provide the best repair of the muscle tissue and protein synthesis (
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Furthermore, protein intake after resistance training has shown to improve protein balance in the body and reduce muscle damage and delayed onset muscle soreness (DOMS) (1,7,15). The benefits of supplementing protein with resistance training can be an increase in lean body mass as well as strength gains. As shown in a recent study, the strength gains of athletes taking protein supplements were significantly increased as opposed to the strength gains of athletes not consuming protein supplements, which showed little to no significant differences in strength gain (10). In a similar study regarding strength gains with protein supplementation, participants in a 10-week resistance training experiment showed strength adaptations through greater prevention of catabolism and an improved anabolic response. In other words, with protein supplementation, the participants’ bodies were building up proteins (anabolism) in the muscle instead of breaking them down (catabolism) (9).
Conclusion
As based upon published research, protein supplementation, when consumed properly, appears to have a positive impact on strength gains, protein synthesis, lean body mass, and reduce recovery time. Of course, protein supplementation should be used to “supplement” a well-balanced diet already in place, not replace it. While protein supplements may be beneficial, foods can offer the same benefits as long as adequate protein is ingested. Supplementation can be used to help meet the protein demands needed by the body to keep up with a resistance training program, though. As evidenced by research, individuals taking protein supplements can see results in as little as six weeks. It should be noted that currently, there is no published research stating that protein supplementation has a negative long-term effect. When taken in moderation, and by the guidelines specified, protein supplementation can have a positive outcome on performance and health in those individuals involved in resistance training.
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The NSCA's Performance Training Journal is a bimonthly, online-only publication that provides informative strength and conditioning topics based on sound research and practical application. The Performance Training Journal is available to NSCA Members.
About the Author
Russell Abaray is currently working as a graduate assistant with the Lamar University Athletic program in the strength and conditioning area. He is a United States Weightlifting Level 1 Sport Performance Coach, and recently completed his Masters degree in Kinesiology. Abaray has also earned the SCCC credential through the Collegiate Strength and Conditioning Coaches Association. Douglas Boatwright is currently a Professor/Department Chair of Exercise Science in the Department of Health and Kinesiology at Lamar University.
