Misconceptions about Carb Loading in Triathlon

TriDot Triathlon Training Misconceptions about Carb Loading

At some point over the past four decades or so athletes created a picture in their mind of what carb loading looks like. And that image became a big bowl of pasta the night before a race. In reality, effective carb loading for any endurance event, much less triathlon, is much more involved than this.

First of all, why do we “load” carbs prior to a race?

The reason is because of glycogen. Glycogen is the most accessible store of energy in the body. Glycogen is what you’ll be burning as fuel during a triathlon.

When you eat something like pizza, most of the carbohydrates from that pizza get stored as glycogen in your body. Thus, eat pizza the day before your race and have more glycogen, right?

Except glycogen is not all of what you use during a triathlon. You also burn fat. The downside is fat is not as easily utilized and there’s much less of it.

This brings us to our first misconception. For triathletes aware of the importance of glycogen, they oftentimes believe that this is the only store of energy that can be utilized during training and racing. However with the right kind of nutrition, you can actually teach your body to use fat as a fuel more effectively.

Replenishing glycogen requires a certain type of food and drink, which typically spikes your blood sugar. Think pasta and gels and Gatorade. Destabilized blood sugar means highs and lows. What goes up must come down. A body that is inefficient in handling blood sugar spikes will crash easier.

But if you can be more efficient by burning glycogen and fat as fuel, you’ll require less carbs and, therefore, stabilize blood sugar much more efficiently. This means that not only will you be more efficient on the triathlon race course, but you’ll also be able to carb load easier because you’ll need less of it.

If you want to learn more about how to teach your body to burn fat as fuel, check out Generation UCAN or read, "Triathlon Nutrition: Metabolic Efficiency."

Now, back to the original question. If you want to carb load just eat a bowl of pasta the night before your race, right?

Not so fast. When we train, we deplete muscle glycogen stores. When we eat and rest, we replenish glycogen. Then when we go back to training, it gets depleted again. And the cycle repeats itself.

When you’re preparing for a triathlon, hopefully you’re tapering. This means a potentially drastic reduction in glycogen depletion. At this stage, your body is ripe for increasing glycogen muscle stores. But like all good things, it doesn’t happen overnight. One meal isn’t going to fill up your glycogen stores.

Depending on your fitness and ability to burn fat for fuel, carbohydrate loading, according to sports dietitian and IRONMAN U contributor, Monique Ryan, may require anywhere from four to five grams of carbs per pound of body weight per day for around three to four days. Ryan says that the experts have found a 1-2% improvement in IRONMAN triathlon events when athletes have carb loaded in advance. That’s well more than enough for a personal best with all other things being equal.

Four to five grams of carbs per pound of body weight is a lot of carbs. For a 165 lb. triathlete that’s around 3,000 calories of pure carbs each day! Therefore, you might be wondering with the lack of training and the high consumption of carbs if you’re going to get fat in a short amount of time right before your big day.

Ryan assures us that carb loading shouldn’t increase body fat levels. However, you will gain some weight. The added muscle glycogen and retained water during taper time may cause you to gain about three or four pounds. But remember that this is weight you’re going to use during the race. So it’s not something that’s going to slow you down.

But of course, not all carbs are created equal. The type of carbs might make a difference, especially for those who struggle with gastrointestinal issues. Be sure to consume less carbs with fiber and more compact sources like bagels and, yes, pasta.

In fact, you can even reasonably consume some foods that you might not consider super healthy right before your triathlon. The goal is to simply load carbs and deviating from your strict diet for just this short period of time won’t break the bank. But as already stated, be reasonable and only eat foods you know you can trust.


TRIDOT TAKEAWAY: There are a lot of misconceptions about carb loading before a triathlon. It becomes an easier task when your body can burn fat for fuel, it doesn’t happen overnight, and it won’t make you fat. So be sure to smartly carb load before your next triathlon and get that PR just on preparation alone!


TALK WITH TRIDOT: How do you carb load before a triathlon race? What foods do you trust?


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.