Metabolic Efficiency - Unlocking the power of Fat!

Improving your metabolic efficiency (ME) is about training your bodies ability to switch from using carbohydrates as fuel, to fat as fuel, and then back to carbohydrates or any combination of this switching at varying levels of exercise intensity. In effect preserving carbohydrate stores for longer, by burning predominantly fat at ever increasing intensities. 

There will always be a certain point at which your body switches to using carbs.  But through improving ME it should be possible to increase your fat burning capacity when working at higher intensities.  When you consider that most of us have an almost infinite supply of fuel stored as fat and a very limited supply of carbohydrate it stands to reason we should spend some time and effort fine tuning our metabolism to access and utilise fat!

There’s no doubt that the vast majority of endurance athletes could benefit from improved ME, I would say there are a few distinct groups where the benefit is amplified:

  • Those who suffer from gastrointestinal distress during races

  • Those who are participating in the longer endurance events, eg: Half Ironman, Ironman, ultra-marathons or longer distance cycling

  • Those who struggle to lose body fat

There is two sides to improving ME - training and nutrition. Training is not covered in this article but does require spending a lot of time working at the lower end of the intensity scale with plenty of volume in Zone 1&2. This helps facilitate the changes to take place that alter the body’s efficiency in using fats as fuel.  Here are some simple nutrition rules to follow to help improve ME:

  • Reduce your carbohydrate intake during your base phase of training when intensities are generally at the lower end of the spectrum.  Replace with healthy fats.

  • Base meals earlier in the day around fats and proteins.

  • Supplement with Medium Chain Triglycerides.

  • Switch out any processed carbohydrate foods for natural, whole and unprocessed foods like colourful non starchy vegetables and berries, take the majority after training.

  • If you feel hungry eat additional fats or protein.

  • Avoid using nutrition products during training sessions in the base phase.

  • Carbohydrate before training will inhibit fat utilisation and decrease time to exhaustion so reduce use.

  • After an evening training session refrain from taking carbohydrate until after you have trained the next morning.

  • Try an 8-10 hour eating window, as an example finish your last meal at 7pm then have your next meal at 11am the next day.

  • Supplying the the appropriate level of carbohydrates is key.  When you move into your build and competition training phases and are training at higher intensities your requirement will increase.  Increase your carbohydrate intake by introducing more natural, whole and unprocessed carbohydrate sources on the days where you have your hardest or longest sessions.

  • Re-introduce peri training nutrition as needed during the build and competition training phases. If your metabolic efficiency has improved you should find you need less carbohydrate than previous to maintain output.

  • Develop a race plan that reflects your improved ME. You will need some carbohydrate during long races, but it should be less than previous.

By improving your ME you will preserve carbohydrate stores for longer, burn more fat at higher intensities and more than likely get to the finish line faster.

Paul Cadman