Nutrition on multi-day ultramarathons: Why I’m packing protein!

As I pack for tomorrow’s race start – I’m setting off on Costa Rica’s 6-day Coastal Challenge staged ultramarathon – I’m thinking very carefully what I’m going to be eating this next week. Nutrition is a much more important factor in race management on multi-day races than it is on one-day ultramarathons. You’re not just eating to get you through the next couple of hours. You’re fueling your body for the coming days, as well. And that’s why I’m packing lots of protein.

LIMG_1957I used to do a lot more carbs, but over the last two years I’ve been switching to less carbs, and upping my fat and protein. (The high-fat versus high-carb thing will be the subject of a future article or five). But what I’m going to talk about right now is protein, while racing – and an interesting study that was published last month about how a higher-protein diet helps endurance athletes to actually put on muscle – even while operating at a daily calorie deficit.

Hmm, I thought. That sounds like pretty important stuff for multi-day staged ultramarathon runners to know about.

This study was undertaken by a group of researchers from McMaster University, in Hamilton, Ontario, Canada. The abstract is available right now – and the full paper will be publicly available in March.

What these researchers did was to randomly assign a group of young men to either a low-protein group (1.2 g protein per kg of body weight) or a high-protein group (2.4 g protein per kg of body weight). (It’s important to note that even the “low-protein” group was getting 50% more protein than what the general recommended daily allowance is). Both groups ate controlled portions which had them in calorie deficit by about 40% (in other words, they were permanently hungry for the four weeks of the study!). The amount of calories each group received (per body weight) was the same, but the balance of macronutrients was different: carbs were held roughly constant, so the ones on the lower-protein diet made up the difference in fat.

The researchers also had members of both groups (all men who were generally fit and in-shape, although not considered “in training” for a specific event) undertake the same fairly rigorous exercise program, which included resistance training and HIIT (high-intensity interval training), six days a week for the four weeks.

Conclusion? They all lost weight. (Well, duh).

But guess what? The ones on the higher-protein diet actually put on muscle. (Well, strictly speaking, they increased their “lean body mass” – but most of that would be muscle). So the high-protein men gained muscle and lost a lot of fat. The low-protein men lost roughly the same amount of weight in total, but their balance was that they only maintained their muscle mass (which is still pretty astonishing, considering they were functioning at a 40% daily calorie deficit!) and lost less fat than the other group.

We all know that exercise does, generally, increase muscle mass. But functioning at a calorie deficit can counteract that – it can actually break down and consume muscle. What this study appears to show is, that by increasing the protein you eat, you can protect your muscles from breaking down by pushing your body to consume your body fat. You become leaner and stronger!

And what does that mean for me? Well, that study was undertaken over four weeks, and my race is only six days. However, I think many of those same principles, about how to preserve muscle mass while undertaking endurance activities, still apply.

On The Coastal Challenge, our breakfasts and dinners are provided by the race organization. So at those meals I will make sure to eat lots of meat and eggs, and of course black beans (this is Costa Rica!) And on the trail, I’m ditching a lot of the carbs I used to eat, and going for a better balance, mixing a fair bit of protein along with some carbs and fat. Sure, I’ll bring a couple of bars and a gel or two to get me through the final hours of some of the long days. But for the most part, along the trails I will be munching on meat jerky, nuts, and nut butters (and opening those smoked oysters as soon as I get into camp).