The Pros and Cons of Protein Powder for Endurance Athletes
Does it work for you?
Initially, this article was going to be about all the reasons endurance athletes don’t need protein shakes, but that wouldn’t really be fair or accurate. There are some very good reasons for cyclists, runners, and triathletes to consume protein shakes, but they are also often overused, used for the wrong reasons, or used in place of better alternatives. If you use protein powder or are considering using it to boost protein intake, consider the following pros and cons.
Pro: Older athletes benefit from increased protein intake
Growing evidence supports the notion that older adults (50+), particularly older athletes, benefit from increased protein intake. The recommended daily allowance (RDA) for protein is .8 g/kg (about .5g/pound), and increases to 1.2-1.7 g/kg for endurance athletes. Athletes proactively working to gain muscle mass, and athletes in high-power, high-intensity training (e.g. sprinting) may benefit from consuming up to 2g/kg/day, but there is little evidence that consuming above 2g/kg/day adds much additional benefit.
As athletes get older, maintaining muscle mass becomes more of a challenge. In a small 2016 study by Doering et al, older triathletes (avg 53 years old) and younger triathletes (avg 27 years old) were fed the same controlled diet and endured the same high-intensity downhill running workouts for three days. They consumed 20g of isolated protein immediately after the workouts and their controlled diet provided 1.6g/kg of protein per day. Researchers found that, despite protein intake 2x the RDA, the older triathletes had significantly lower muscle protein synthesis compared to the younger triathletes.
The Doering study represents a very high training load (3 days with deliberately muscle-damaging workouts), but it suggests older athletes would most likely benefit from protein consumption at the higher end of the range (1.6-2.0g/kg/day).
So, if older athletes need more protein, then protein powders make it easier to consume more, except that…
Con: You don’t need supplements to get enough protein
Even close to the high end of the recommended consumption of protein (1.8g/kg of bodyweight per day) it’s not that difficult for 70-85 kg (154-187 pound) athlete to consume 126-153 grams of protein in a day. Athletes with mixed diets who eat meat, fish, and dairy have an easier time of it, but nutrition-conscious vegetarians and vegans generally have no problem eating enough protein. Here’s a list of high protein foods (including animal and plant sources) for reference:
Meat (beef, pork, poultry): 20-24 grams per 3 ounce serving
Fish: 21-25 grams per 3 ounce serving
Eggs: 6 grams per egg
Greek yogurt: 23 grams per 8 ounce serving
Cottage cheese: 14 grams per half cup
Lentils – 9 grams per half cup
Tofu – 10 grams of protein per cup
Tempeh – 12 grams per cup
Hemp Seeds – 13 grams in 3 TBSP
Black Beans – 8 grams per half cup
Chickpeas (or hummus) – 8 grams per half cup
Almonds – 7 grams per cup
Quinoa – 8 grams per cup
Soy Milk – 8 grams per cup
Peas – 8 grams per cup
Peanut Butter – 8 grams per 2 TBSP
Black Eyed Peas – 8 grams per half cup
Edamame – 8.5 grams per half cup
Pro: They’re convenient
For a lot of busy athletes who are training hard, a shake made with protein powder sure is convenient.
Con: Protein powders don’t deliver whole foods’ range of nutrients
Perhaps my biggest problem with protein powder is that it often displaces real food in an athlete’s diet, which means athletes miss out on all the other great nutrients those foods would have delivered. The table below is just one example to illustrate the point, from 2018 study by van Vliet:
Of course, there are other protein isolates (whey, casein, etc.) not included in the table, and there are many protein powders fortified with additional (and sometimes massive) amounts of vitamins and minerals. However, when athletes turn to and put their faith in supplements they pay less attention to the quality and variety of their food choices, which is always detrimental in the long run.
Con: Many protein isolates contain a lot of sugar and other additives
Most protein isolates taste awful unless you add flavoring and sweetener to them. In some cases, that means adding as much sugar per serving as a candy bar, soda, or big slice of birthday cake. Or, if you’d rather go sugar-free you can have your fill of artificial sweetener, which isn’t a great option either. And then there’s the vitamin and mineral additions, and more importantly, the ergogenic aids that many manufacturers add to the mix. Some of the ergogenic aids are effective and legal (caffeine) and some are neither. And there’s little way of knowing exactly what’s in that powder at all, because of the Food and Drug Administration’s loose regulations on dietary supplements. In 2017, the Clean Label Project published information suggesting 50% of the protein powders they tested contained unsafe levels of contaminants, including heavy metals. There’s been scientific debate since about their findings, but even if they overstated the extent of the problem, contamination in protein powders is, unfortunately, nothing new.
Pro: Protein powder is a concentrated protein source for athletes looking to lose weight
One of the reasons bodybuilders consume a lot of protein powder – in addition to lots of protein-rich foods – is that eating a lot of whole food protein sources means eating a lot of total calories and large volume of food. Cyclists, triathletes, and runners often consume concentrated sources of carbohydrate (gels, chews, bars, sports drinks) during workouts and events precisely because they deliver carbohydrate without all the other stuff (protein, fat, fiber). Athletes who are training hard and trying to maintain muscle mass and training quality while dropping bodyweight may benefit from consuming concentrated protein sources. It is also important, however, for these athletes to consume adequate total energy to support their training, as well as adequate carbohydrate to fuel high-intensity training efforts.
My recommendation to the athletes I work with – especially the athletes over 50 years old – is to focus on consuming the protein they need through whole foods, and make adjustments to their food choices to increase protein intake if necessary. In my view, protein powders are a last resort and there is almost always a better way to fulfill an athlete’s requirement for protein.
Chris Carmichael CEO/Head Coach of CTS
Doering, Thomas M., et al. “Lower Integrated Muscle Protein Synthesis in Masters Compared with Younger Athletes.” Medicine & Science in Sports & Exercise, vol. 48, no. 8, 2016, pp. 1613–1618., doi:10.1249/mss.0000000000000935.
van Vliet, Stephan & Beals, Joseph & Martinez, Isabel & Skinner, Sarah & Burd, Nicholas. (2018). Achieving Optimal Post-Exercise Muscle Protein Remodeling in Physically Active Adults through Whole Food Consumption. Nutrients. 10. 224. 10.3390/nu10020224.