Sticking to a diet you’ve downloaded from the internet without actually knowing how food behaves in your body is like running up a mountain with a blindfold on. To truly get the most from your training, you should know how each macronutrient works and why you need them.

Carbohydrates

Carbohydrates have always been a runner’s best friend. As a fuel source, carbs help your body replace the glycogen that is depleted during your training and events. Whether it’s a quick burst of refined carbohydrate through an energy gel during the race or a night of fuelling up on wholegrains, carbs are your ally. Carbs can’t be stored in large amounts in the body (we only store one or two days’ worth) so are burned as fuel – making them the most readily accessed fuel source.

When to take carbs: your carb intake should be upped on days when you’re training heavily or during the day before a race. Try to avoid fibrous wholegrains the day of a race though, as they are quicker to digest and can cause stomach problems mid-run. Carbs will be your main source of fuel as a trail runner, so get to know which types agree with you and which don’t.

Fats

Fats provide roughly half your body’s energy needs. The fat from food sources is broken down into fatty acids which feed your cells. However, excess fats are stored away in fat cells called triglycerides. Excess carbohydrates that aren’t used as fuel can be converted to fat and stored in this way. The body is good at storing fat, which is why it’s fairly easy to pile weight on when you’re living a sedentary lifestyle.

Not all fats are bad, however, as your body needs fat to function. For instance, monosaturated fats keep your LDL levels in check (bad cholesterol) and increase your HDL (good cholesterol.) Fortunately, this type of fat is found in avocados, oils and nuts like cashews, almonds and hazelnuts – so break out the trail mix.

Fats help act as shock absorbers for the bones and also ensure the normal function of cells. For an athlete, 50-60% of energy expenditure used during exercise comes from fatty acids – specifically during periods of low intensity, high duration bouts like distance jogs.

When to take fats: ‘good’ fats should be a part of your daily meal plan as a runner — a constant source to help keep your levels in check.

Protein

Whether you’re guzzling down protein shakes or sitting down to a steak dinner post-race, protein is the food source responsible for muscle maintenance and recovery. Protein in food is broken into amino acids and these are used to build new proteins that facilitate the anabolic process of the body that are responsible for new cell growth.

Protein can also be used as a source of energy when there is a shortage of fats or carbs. However, when it comes to recovery, protein is a must. Runners may be pleased to know that an intake of protein following a hard run can help your body recover. Aside from post-run, steady consumption of protein is essential for fuelling muscle maintenance. Don’t be afraid to suddenly bulk up – protein intake alone won’t increase mass.

When to take protein: ideally you’ll be consuming around 1.6-2g of protein per kilo of bodyweight throughout a day – but the key moment to take protein is within 30 minutes of finishing a run. Consume no more than 30g at a time, as excess protein is expelled as waste.