For athletes, the importance of a high protein diet cannot be overstated. After all, the amino acids that make up proteins are fundamental building blocks of lean muscle tissue as well as important signalling molecules that boost protein synthesis, fat loss, satiety (i.e., feeling of fullness after a meal), and overall health. At the end of the day, research has shown that keeping dietary protein high will indisputably aid in muscle building and recovery, while keeping you lean.
Recent work published in The American Journal of Clinical Nutrition illustrates several mechanisms by which a high protein diet maintains muscle mass, while promoting fat loss. We have summarized these mechanisms in the following 5 points:
- High protein meals produce the greatest increase in metabolic rate and thermogenesis (i.e., production of body heat). In general, dietary protein requires 20–30% of its usable energy to be burned for metabolism and/or storage, whereas carbohydrates require 5–10% and dietary fats require 0–3%. If you have ever ate a massive steak and had the “meat sweats” immediately after, then you have experienced the thermic effect of a high protein meal!
- Meals that are protein rich (at least 25-30g per meal) are much more satiating (satisfying/filling) than high fat or high carbohydrate meals. Generally, subjects on high-protein/low calorie diets report greater satiety and overall satisfaction than those on lower-protein diets of the same caloric content. This is important because diet success is dependent on keeping food cravings to a minimum.
- High-protein diets shift the ratio between fat-mass and muscle mass in favor of muscle mass. Research illustrates that high-protein diets promote greater loss of fat-mass while maintaining lean (muscle) mass, even while in caloric deficit.
- Those who achieve their lean physique through high-protein diets tend to maintain fat-loss better than others. This is due to positive alterations in the metabolic profile of those who eat a high protein diet.
ACTION POINT: As outlined in this article, the generally recommended protein requirements are 1.2 to 1.6 g/kg body weight/day. However, for athletes and those who train heavily and frequently, the protein requirements are about 2x the general population. As such, we recommend a protein intake of 2.2 to 3.5 g/kg body weight/day or 1 to 1.5 g/ lb body weight/day (e.g. 200 lb man would take in 200 to 300g of protein per day). The best way to assure you get all the protein you need is to eat high protein meals (30-40g per meal) and use a high quality protein supplement.
Reference: Leidy HJ, Clifton PM, Astrup A, Wycherley TP, Westerterp-Plantenga MS, Luscombe-Marsh ND, Woods SC, Mattes RD. The role of protein in weight loss and maintenance. Am J Clin Nutr. 2015 Apr 29. pii: ajcn084038. [Epub ahead of print]