Trail running in the Italian Dolomites

The way we currently fuel for energy is to rely on carbohydrates (carbs) to give us energy.  However carbs are not the only fuel source we have as nutrition for endurance athletes, we can also train our bodies to use fat for fuel.  The problem with being an endurance athlete and using carbs as our primary fuel is that we have a very limited storage capacity for carbs.  On average we can store 500g of carbohydrate (as glycogen) or 2000cal. However after about 40-45 minutes of training or racing, you have used the stored glycogen and need to either replenish with gels, or force your body to break down another source for energy.  This becomes inefficient, and the timing of gels is integral to ongoing energy and to prevent hitting the wall or “bonking” in marathon terms.

The other option of nutrition for endurance athletes is to train our bodies to use fat as our primary fuel.   In order to use fat for fuel you must first keto-adapt and essentially force your body to use fat as the fuel source.  Once this adaption has occurred you will use fat efficiently as the primary fuel source for sustained ongoing energy. Therefore you are turning carbohydrate and glycogen into secondary fuels.  Once you make this transition you can then train harder, perform longer and recover faster.

In terms of numbers, even a lean endurance athlete, at say 75kgs, still has about 5.3kg of fat, which in terms of calories is around 47,700cal.  So that is 47,700cal stored as fat compared to 2000cal stored as carbs. This represents a huge fuel capacity in stored fat that can be tapped into and used as the primary fuel source.  In the keto-adapted athlete they are able to utilise this fat source for energy and avoid reliance on the constant supply of carbohydrates from gels. It also allows easy control of ideal body composition and regulation of hunger.

If you are struggling with nutrition to support your training and are interested in what the diet looks like in terms of foods and how to implement it, then please call Waverley Central Chiropractic Clinic on 9545 0278 to book a Dietetics consultation today.