The Pros and Cons of Protein Supplements for Endurance Athletes

by Chris Carmichael
CEO/Head Coach of CTS

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 1.2-1.6 g/kg for endurance athletes. For Masters age endurance athletes, recommended daily protein intake increases to 1.6-1.8 g/kg. (Desbrow, 2019) 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.

Free Cycling Training Assessment Quiz

Take our free 2-minute quiz to discover how effective your training is and get recommendations for how you can improve.

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.


Desbrow, Ben, et al. “Nutrition for Special Populations: Young, Female, and Masters Athletes.” International Journal of Sport Nutrition and Exercise Metabolism, vol. 29, no. 2, 2019, pp. 220–227., doi:10.1123/ijsnem.2018-0269.

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.

FREE Mini-Course: Learn How to Maximize Your Limited Training Time

Learn step-by-step how to overcome limited training time and get faster. Walk away with a personalized plan to increase your performance.

This field is for validation purposes and should be left unchanged.

Comments 20

  1. Pingback: 6 Top Supplements To Boost Muscle Gain - The Lagos Stylist

  2. Really informative article, people are really prone to have supplements. This is a good article to gain some meaning full and concrete information.

  3. How does this apply to a higher protein recovery drink within 20 minutes of a “Strenuous” workout? Thanks.

  4. As I’ve mentioned before in similar articles, it’s hard to get the recommended amount of protein entirely from whole foods if you are eating a plant-based diet. Despite that Chris says you can.

    I’m a 52 yr old masters athlete and weigh 65kg. My protein target should be 104-117 grams. This would be a ton of protein from whole, plant-based foods. I added up several permutations of meals and I would have to eat way too many calories from whole foods in order to get the recommended protein. This would cause weight gain and I literally couldn’t eat that much anyway.

    I challenge Chris and anyone else who is curious to write up a meal plan for a day that shows how you can get this much protein from whole, plant-based foods without overeating calories. Also it has to be realistic — no one can eat 7-8 cups of tofu or beans per day or something silly like that. Please post your meal plan — seriously, please post one here. I tried this and for me, it just works better to get some of the protein from powder.

    Despite this, my recovery is definitely, noticeably better when I get the recommended amount of protein.

    1. When you say plant based, are you saying vegan or vegetarian? It is true that vegan diets can make it harder to hit your protein goals if you are calorie restricted but it’s definitely not impossible without supplements. Have you tried to make seitan, which is primarily made from vital wheat gluten? I make a simple version and two servings of that is 343 calories with about 48 grams of protein. 300g of Greek yogurt is about 170 calories with about 30g of protein. Greek yogurt doesn’t work if you are sticking to a vegan diet but there are options out there. I routinely eat about 170g of protein a day in a 2k calorie per day diet and I could definitely hit that without eating any meat. I could also do that with seitan and other plant based sources.

  5. How about as a vehicle to deliver amino acids to repair muscle tissue after workout? Any evidence of being able to improve the recovery time of a higher volume athlete?

  6. Pingback: 6 Steps to Ride Strong on Back-to-Back Big Days - CTS

  7. Pingback: Supplements: The Best Way To Get Essential Nutrients Or A Death-Trap? – The Three Step Guide To Looking Your Best

  8. Excellent goods from you, man. I’ve take into account your stuff previous
    to and you’re simply extremely great. I actually like what you’ve obtained here, really like what
    you’re saying and the way through which you are saying it.

    You make it entertaining and you still take care of to
    stay it sensible. I can not wait to learn much more from you.
    That is really a great website.

  9. This is cool – thanks for all this info! I am vegan and supplementing my daily intakes with protein powders now (Vega, and PB Fit for now) but appreciate all the stats on whole foods. The only thing about that chart though is that regular Milk and Skim milk are heavily fortified, have added vitamin D and such, so they can hardly be considered “whole foods” when placed against, for instance, Tempeh (which is not containing artificially added vitamins) but overall this has been so helpful for my understanding more about the protein levels I need and I appreciate the reinforcement, to try to get as much as possible from Whole Foods. Am going to pay much more attention, but still do protein bars and shakes as added reinforcement. Going to add in more flax seeds to my diet, too (what a powerhouse!) Again, thank you!

  10. Pingback: 6 Steps to Ride Stronger Tomorrow - CTS

  11. Pingback: The 7 Worst Post-Workout Habits for Cyclists, Runners, and Triathletes - CTS

  12. That was a great article. Thanks for sharing it. I’m sure each of the readers will interpret it a bit differently around their own circumstances. I was doing challenging 2+ hr endurance workouts/day a year and a half ago and all of a sudden within a few months I had a tear in my groin, tear in my knee and other ailments resulting in 2 surgeries. It was easy to conclude at the time that it was due to overtraining. However, later I realized the most significant contributor was that I did not have enough protein in my diet. I wasn’t even close. It caught up with me. I was using gels and drinks for carbs, using pills to supplement aminos and drinks to help muscle recovery. However, a foundational problem was I was not getting sufficient proteins. I’ll be revisiting my actual protein intakes based on the data in this article. Thanks Chris!

  13. This is why you see so many skinny fat doughy looking endurance athletes walking around. They don’t pay enough attention to macro ratios and generally eat too much. Yes you need about 1g of protein for every pound of body weight but you also need to not overeat and many of the cited protein sources (legumes etc) are also high carb. If your goals are endurance fitness without sacrificing body composition then you probably want to stick with your protein supplement — the cleaner the better.

  14. Randell.. Have you tried any protein powders by JayRobb?? He has Egg and Whey powders w no soy, gluten, non-GMO, etc but to me, tastes great! I’m a 54-year old woman w more muscle than some men and other than ‘real’ food I do supplement w this powder in my morning coffee.. bliss 😊

  15. Still a part of my recovery drink after a long ride or a hard gym session but i have to agree that whole food sources are much better, for all the extra nutrients but especially for the better digestion they provide.. Protein powder, especially in high doses tend to create a lot of gases, if you know what i mean 🙂

  16. Guys, how can we be saying 20 grams per 3 ounce serving. Surely we should stick to either metric or imperial, or else provide both. Constantly having to look for diversion tables is really frustrating.

  17. Great piece. I’m 54, mostly vegan and have just ramped up my cycling to lose weight and to prepare for a significant goal. I eat healthfully but I have benefitted from adding a single scoop of Bob’s Red Mill pea protein powder sweetened with monk fruit – it adds some “muscle” to my morning smoothie (marionberries, spinach, chia flax & hemp, a date, coconut water or kombucha, ginger and an ounce of almonds). I’ve noticed a positive effect in endurance but still need long muscle recovery times. Thanks for the useful info!!!

  18. Thank you. I have wondered about that for awhile. I am a 54 yr old cyclist that is working on loosing body fat and gaining muscle mass. I have had a hard ti.e finding any powders that I can like.

Leave a Reply

Your email address will not be published. Required fields are marked *