Building Aerobic Endurance Through a Good Diet – For Triathletes and Triathlons

To become an endurance athlete you have to provide high-quality raw materials in your diet and the right training to allow the body to best adapt. Both good health and good fitness come from feeding and exercising the body in the right proportions.

Eat fat, burn fat

To maintain optimal fitness, your diet should contain quality sources of fat, amounting to one-quarter or one-third of calories consumed. However, as fat has over twice the energy per gram compared to carbohydrates or protein, you do not need large amounts. A triathlete consuming 3,000 calories in a day needs just 70-90 grams of fat to be in the optimal zone. Research has shown that athletes who cut fat their intake to very low levels actually reduce their fitness and endurance.

High-carb diets

The high-carbohydrate diet, often recommended for athletes and usually recommending that more than 70 per cent of calories should come from carb-rich foods, is actually too high. This leaves little room for fats and protein (only 30 per cent) and restricts food choice. More than 50 per cent is a better target, so you can enjoy carb-rich meals but include good fat and protein sources. Too many carbohydrates in the diet may actually switch the muscles into using carbohydrates instead of fat and cause the body to store fat. Ironically, slightly more fat than was often thought ideal in the diet allows you to be leaner, use fat better as a fuel and eat a more varied diet.

Stress and eating

Aerobic training at a comfortable pace leads to a more controlled appetite and improved ability to cope with stress. This translates into more control of your diet. You binge less, time your foods to suit your activity better and teach your body to use fat as a fuel. Muscles always have to use a small amount of carbohydrates, even at low training speeds.

Losing body fat

To make your body lose fat, you need to create a deficit of calories, ie less in and more out. If you exercise an additional 300 calories a day, drop your food intake 200 calories and train correctly you can lose over a pound of weight (450 grams) per week. You are not starving yourself: your body taps into stored fats to cover the deficit and you've made only minor activity and diet alterations. Do this and months later you'll be leaner, fitter and healthier.

Did you know?

Less than 25-50 grams of fat is likely to be used in 90 minutes of training if you pace correctly and have a good fitness level. You may use over half your muscle glycogen stores in the same session if the pace is fast or the terrain is hilly. So you always need carbohydrates, even at modest training speeds – while fat stores come down very slowly