Become a GI Joe(e)
Just what exactly is the glycaemic index anyway? We take a look at what it means and how you can use it to better fuel your cycling.
What is GI?
The glycaemic index –GI – is a measure of the effect carbohydrates in food have on your blood sugar levels. All values are compared to pure carbohydrate in the form of glucose, which scores 100. Everything else will be lower than this but the higher the score, the quicker the release of sugar into the blood.
Foods are classified as low GI, moderate GI and high GI. They all have a role in your diet depending on the type and intensity of activity you’re doing. As a rule, foods with a value of 70 or over are high GI, 56-69 medium and 55 or less are low.
Guidelines suggest that before a long ride it is best to eat meals containing both low and moderate GI foods. Good examples for breakfast include porridge (low) with honey (moderate). This will ensure a gradual release of energy so you can maintain exercise intensity for longer. Alternatives are beans on wholemeal toast or a granary bagel with honey, jam or marmalade. If the ride is later on in the day or it’s an all-day event, eat a low/moderate GI meal for lunch, such as wholemeal pasta with tomato sauce, lean protein sandwiches on wholegrain or granary bread or wholewheat wraps, or jacket potatoes with low fat fillings like tuna.
If correct carb loading is done and your glycogen stores are full prior to exercise, this will be enough to sustain you for 60-90 minutes. After this you will need extra carbohydrate, best met by eating high GI foods that can release energy quickly. Sports gels and energy bars are the obvious choice, or you could use this as a licence to indulge in chocolate brownies, cereal bars, jelly babies, dried fruit, and white bread jam or Marmite sandwiches.
High GI foods are also useful immediately after a long ride or race in order to enhance muscle recovery. This can be further improved by adding protein. Flavoured milk is an ideal choice as it combines all these elements. This should then be followed up with some low GI foods to steadily replenish your glycogen stores. Peanut butter on wholegrain bagel, oatcakes with hummus, chicken stir-fry with buckwheat noodles or salmon with baked sweet potato all make great post-ride low GI meals.