High Protein Diet for High-Quality Weight Loss in Elite Athletes

High Protein Diet for High-Quality Weight Loss in Elite Athletes

A Retrospective Review by Andrea Zerbe, CSCS

04/13/2021

Weight loss is a tricky topic, especially tricky when it comes to elite and professional athletes. Between the high prevalence of eating disorders, obesity, and fad diets it feels impossible to decipher what is safe, healthy, and effective when it comes to weight loss. Luckily, there may finally be some scientifically based answers. Numerous studies are revealing that a high protein diet and resistance training while lowering caloric intake could be a very effective tool at achieving high-quality weight loss for elite athletes. This article is a retrospective review that dives into high protein diets as a means of high-quality weight loss.

Firstly, to define what high-quality weight loss is. High-quality weight loss (HQWL) is the decrease in fat mass with the maintenance or increase in lean body mass. This is the optimal form of weight loss especially for athletes due to the retention and or increase in lean body mass. Lean body mass retention and muscle protein synthesis, in other words muscle mass retention and muscle growth, is imperative for athletes to continue optimal athletic performance.

Secondly, it’s important to look at what lowering caloric intake means. A lower caloric intake or energy deficit means that caloric intake is less than caloric expenditure. Less coming in than going out. This is a balancing act. If the scales are tipped too much, as in not enough deficit, then weight loss may not happen. But, if there is too much deficit, negative performance and health outcomes can ensue. Actually, if caloric deficit becomes too great and is not supplemented with protein, athletes risk losing up to 25% of lean body mass. This lean body mass loss could result in huge decrements in athletic performance. It is generally recommended for safe weight loss that the energy deficit is no more than ~500kcal (Calories) per day.

Lastly, a few disclaimers. This is not a recommendation or prescription, but a report on current scientific findings written in digestible language. Secondly, the scientific findings in the studies sighted are not all conducted on athletes but on obese adults, these findings are proposed to be translatable to athletes. Lastly, eating disorders and performance enhancer abuse are legitimate problems in all sports. Please consult a professional if you feel like you may be suffering.

The next five sections will explore scientific findings on the recommended quantity of protein, the timing/dosage and quality of protein, protein supplements, the effects of a high protein diet on health and performance, and weight loss supplements all of which related to HQWL for athletes.

Quantity of Protein

It has been well established that the recommended dietary allowance (RDA) of protein is 0.8g protein/kg body weight/day. This is the recommendation to meet the needs of most people which does not include athletes, much less athletes on a high protein diet. This being said, studies have revealed that individuals trying to achieve HQWL do require a much higher daily protein intake. It was found that a protein intake of 1.6-2.4 g protein/kg body weight/day was most effective at promoting lean body mass retention and fat loss during energy deficit when combined with resistance training. This increased amount of protein is still well within AMDR recommendations. Where an individual falls in this range is dependent on training and the size of the energy deficit. As training and or the energy deficit increases, protein intake should also increase to preserve lean body mass for HQWL. It should be noted that intakes above 2.4 g protein/kg body weight/day do not result in significant lean body mass retention or gain.

Timing, Dosage, and Quality of Protein

Now that it’s been discussed how much protein an individual needs daily, there are three other variables scientists have looked at when using high protein diets as a means for HQWL: timing, dosage, and quality of the protein. Primarily, timing and dosage of protein intake have been sighted to help lean body mass retention and muscle protein synthesis during energy deficit. Timing and dosage refer to the frequency, time of day, and amount of protein consumed in a sitting. In one study the frequency of protein consumption has been demonstrated to be more effective if more protein is consumed less often as compared to less protein more often. Another study looked at the difference between a balanced protein dosage (same amount of protein at each meal) and a daily consistent rise in protein dosage (breakfast has the least amount of protein, lunch more, and dinner with the most). The study found that the balanced protein regimen was better for muscle protein synthesis than the daily consistent rise in protein dosage. Finally, a study proposed that pre sleep protein could be another effective strategy for lean body mass retention during energy deficit. As for the quality of protein, studies have found that it can also have significant effects on lean body mass retention and muscle protein synthesis. Protein quality refers to not only the amount of protein in a protein source, but the number of essential amino acids, amount of branched chain amino acids, and the absorption rate of the protein. Both the number of essential amino acids and branched chain amino acids in a protein source have effects on muscle protein synthesis. As the amount of both essential amino acids and branched chain amino acids consumed increases, the more that muscle protein synthesis is stimulated. Animal proteins are much higher in essential amino acids and branched chain amino acids as compared to plant sources of protein including the complete protein soy. Animal sources of protein also have a better absorption rate than plant sources, meaning that your body is able to use more of the protein ingested from animal sources than plant. All in all, the timing, dosage, and quality of the protein ingested has effects on lean body mass retention and muscle protein synthesis during energy deficit, which should be noted for athletes trying to achieve HQWL.

Protein Derived Supplements

Protein supplements are a commonly used supplement among athletes, and for good reason. Protein supplements are an easy way to get a lot of protein without a lot of calories. Not to mention, the effectiveness of protein supplements is overwhelmingly promising. In a study that examines the protein supplement whey, it found that whey could be a very useful tool for lean body mass retention during energy deficit when combined with resistance training. Other protein supplements such as isolated branched chain amino acids have been examined and found to be equally as effective as whey. Overall, protein supplements appear to be a very useful addition to a high protein diet when attempting HQWL.

High Protein Diet Effects on Health and Performance

A big concern for high protein diets is its effects on health and performance. Luckily there has been no evidence that a high protein diet results in any decrements in health or performance. A high protein diet is safe and does not affect the functioning of the kidneys, liver, blood lipid levels, and or bone health. And for some athletes may even increase performance ability due to increased power to mass ratio. It should be noted that the leaner the athlete prior to a high protein diet, the more susceptible they are to lean body mass loss. Although a high protein diet is safe, when it is paired with rapid weight loss it can have devastating effects on health and performance. Rapid weight loss is the consumption of less than 30kcal/kg fat free mass/day which is roughly equivalent to an individual’s resting metabolic rate. The severe energy deficit can cause lean body mass loss, fatigue, hormonal imbalances, physiological issues, and decreased performance. Therefore, while a high protein diet is safe for the health and performance of athletes, rapid weight loss can be extremely dangerous and should be avoided.

Weight Loss Supplements

Weight loss supplements include all supplements aimed at “weight loss” that are beyond protein and amino acid derived supplements. These supplements have contradictory results with dangerous side effects. Not to mention that some of these supplements, such as Ephedra, are banned in many countries and all sports. If athletes partake in these supplements they risk getting caught for doping in sport. These supplements should not be used for safety and ethical reasons.

Summary

Overall high protein diets paired with resistance training can be a safe and effective way for achieving high-quality weight loss (HQWL). The quantity, timing, dosage, and quality of the protein can have effects on muscle protein synthesis and lean body mass retention. Protein supplements can be another safe and effective means to get protein into the diet for HQWL. While high protein diets are safe, rapid weight loss and weight loss supplements should be avoided for safety and ethical reasons. (1)

Resources

1) Hector, A. J., & Phillips, S. M. (2018). Protein Recommendations for Weight Loss in Elite Athletes: A Focus on Body Composition and Performance, International Journal of Sport Nutrition and Exercise Metabolism, 28(2), 170-177. Retrieved Apr 1, 2021, from http://journals.humankinetics.com/view/journals/ijsnem/28/2/article-p170.xml