Carbohydrates (sugars and starches) constitute a vital source of energy during any workout. One of the most important elements
of nutrition and exercise is learning how to control your blood sugar to optimise energy levels. The body has the ability to turn
carbohydrate, protein and fat into energy, but the easiest food to convert is carbohydrate.
Some carbohydrates are converted into energy more easily and effectively than others. How can you tell whether your favourite
sports drink will give you the best energy boost before your workout, and whether pasta is the best pre-race meal?
The Glycaemic Index (GI) provides a way to rank carbohydrate-rich foods according to the glucose levels in the blood after intake.
Blood sugar levels fluctuate throughout the day and we need to stabilise them to achieve optimal performance.
- Fast-releasing energy or high-GI foods will cause the blood sugar to rise sharply, triggering the release of insulin,
followed some time later by an energy lull.
- Slow releasing energy or low-GI foods maintain a more consistent energy supply.
The trick is to combine low-GI carbohydrates with fibre-rich foods such as fruits and vegetables and a little protein, which
slows down energy release, to maintain a consistent level of energy. Consumption of low-GI carbohydrate-rich foods such as
mixed-grain bread, oats, brown rice, carrots, pasta, baked beans, lentils, apples, better regulates metabolism, making more
energy available for exercise. Food and drinks that are moderate-GI such as bananas, soft drinks and rice to high-GI such as
sports drinks, baked potatoes, honey and white rice enhance glycogen storage after exercise, compared with lower-GI foods. In essence:
- Eat low-GI foods or drinks before exercise
- Eat high to moderate GI foods during and immediately following exercise.
Athletes have individual preferences and you will need to discover what works best for you, based on the principles above.