Triathlon Training: What’s Really Required When It Comes to Protein?

Protein is a hot topic among triathletes these days. Hearsay and the wrong advice often flood the triathlon marketplace of ideas. Amidst the confusion, several questions regarding this subject demand answers. How much should I consume daily? Should I be consuming protein before my workout? During? After? What’s really required when it comes to protein?

Let’s take one step back first. What exactly is protein anyway?

Protein is one of the three macronutrients and is essential for building muscle mass. The other two macronutrients are carbohydrates and fat. Carbs provide the energy for our muscles. Fat does the same as a reserve along with protecting our overall body with much needed insulation. What’s been trending for the past decade or so is that carbs and fat are bad, thus leading to the rise of the high protein diet. This isn’t particularly true but that’s a subject for another day.

Generally, however, most triathletes know that they need carbs and good fats for a healthy endurance lifestyle. Still, this leaves protein and the mystery of how much is enough. Sometimes you’ll hear nutritionists talk about a 60/20/20 ratio of the macronutrients. This means 60% of your diet is carbohydrates, 20% from fat, and the last 20% from protein. That may work for the typical person but what about the athlete? And is this ratio even accurate in the first place?

Asker Jeukendrup, Ph.D., an exercise physiologist at the University of Birmingham in England and one of the world’s leading experts on the subject relative to endurance performance, says that the ratios are pretty much meaningless anyway. So don’t worry about it!

“Percentages are meaningless, because it is the absolute amount of carbohydrate and protein that matters. How much you need depends on your goals and the amount of training you do.”

What Jeukendrup means: stop trying to proportion the three macronutrients in relation to each other. Instead, simply find out how much carbs, fat, and protein you need based on the type of activity you’re doing and stick to that intake.

Unfortunately, this is where the water gets muddy. How much protein you need to consume will depend on your body weight and how many hours and what intensity you’re putting into your triathlon training. So then the question becomes how many grams of protein per kilogram of body weight is ideal for you?

Kim Mueller, MS, RD, CSSD, a registered dietitian and board certified specialist in sports dietetics, wrote in IRONMAN, “The Academy of Nutrition and Dietetics and American College of Sports Medicine recommend 1.2-1.4 grams of protein per kilogram of body weight for endurance athletes.” Of course, the more extreme you get the more protein you’ll need.

Mueller recommends that the longer and harder you train, the more your protein intake should vary:

  • On rest days, target 0.8-1.0 grams/kg/day
  • If you train <1 hour, target 1.0-1.2 grams/kg/day
  • If you train 1-2 hours, target 1.2-1.4 grams/kg/day
  • If you train 2-4 hours, target 1.4-1.7 grams/kg/day
  • If you train 4+ hours, target 1.7-2.0 grams/kg/day

Jeukendrup has even gone as far to say that 3 grams per kg per day could help the most elite athlete. He studied that this amount improved the performance of a group of elite cyclists under an intense load of training.

Now while the amount of protein does factor into your overall triathlon performance, even more important is the timing. The studies have shown that consuming protein before, during, and after workouts helps to prevent muscle protein breakdown.

The key takeaway from this, however, is that you don’t need a lot. Mueller suggests that 20 grams of protein one hour before, 20 grams spread throughout a workout lasting over an hour or more, and 20-25 grams immediately after exercise all help to boost the rate of muscle protein synthesis.  

This means faster muscle repair, better response to triathlon training, and an overall faster recovery.

Remember that our bodies don’t have the ability to store protein, so be sure to spread your consumption evenly throughout meals. In other words, don’t try to consume your daily protein demand all at dinnertime. Plan ahead and stay disciplined.



Protein consumption when triathlon training isn’t part of a ratio. Consume the total amount you need each day and be sure to get protein before, during, and after heavy workouts.


How do you consume your protein? What’s your favorite protein shake?

JARED MILAM is a professional triathlete, TriDot coach, and member of the Tri4Him Pro Team. He has 16 years of competitive running experience and 11 years of competitive triathlon experience with a half Iron PR of 3:59 and a full Iron PR of 8:30. Coaching under the TriDot system since 2011, Jared loves working with aspiring triathletes of all ages and performance levels.


Fitzgerald, Matt. “What is the Right Balance of Carbs, Fat and Protein?” Triathlete. Competitor Group, Inc., 13 May 2015. Web. 20 May 2016.

Mueller, Kim. “The Triathlete’s Guide to Protein.” IRONMAN. World Triathlon Corporation, 19 Jan 2016. Web. 20 May 2016.

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