By Sam Challis, Cyclist Magazine, Issue 41 – November 2015
In the land of cycling nutrition, carbohydrate is king. It provides the quick hit of energy required to get riders through the interval sessions that we’re told we need to build power and speed. The result is that we have become loyal subjects to the mighty carbs, and our bodies have become reliant on them for fuelling our rides. But it could be that we are serving the wrong master. Broadly speaking, the average cyclist carries enough glycogen (carbohydrate stored in the muscles) to fuel about 90 minutes of activity – barely enough to get most riders to their first cafe stop. Further, carbohydrate oxidation (ie burning energy) has a strong correlation with lactate production, which limits performance. So to improve, we need to become more metabolically efficient, which is why Cyclist has come to Guru Performance in Mayfair, London, to see Laurent Bannock, a scientist at the forefront of metabolic efficiency training.
All hail fat
‘Metabolic efficiency is the ability of an individual to utilise their most significant on-board fuel supply – body fat – for as much of the exercise duration as possible,’ Bannock says. ‘Fat is the most sustainable energy source for an athlete, and delays the accumulation of lactic acid by sparing glycogen stores. However the situation is complicated by the fact that an athlete must also be metabolically flexible – able to switch rapidly and proficiently between the body’s fuel sources to match the fluctuating intensities of competitive events. Don’t worry, we’ll revisit this later,’ he tells me with a grin, as if sensing my growing incomprehension.
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