Cycling season is in full force. And with a wide range of energy drinks, protein bars, gels and supplements, its hard to know what’s what sometimes.
The best way to understand what sources of energy our bodies need, is to understand how we get energy from food.
The short story:
Digestive enzymes in your stomach will convert your food into fuel for you body to function. We begin breaking down proteins into their building blocks, which are called amino acids. We break down carbohydrates into its smallest subunit, glucose. We take large molecules of fat, and break them into fatty acids and glycerol.
While your digestive enzymes are hard at work breaking down the carbs, your pancreas is put to work. The pancreas is responsible for releasing a hormone we are all familiar with: Insulin. Insulin’s job is to move the glucose out of your blood and into your cells. Insulin will work to keep your level of blood sugar within normal range. Glucose is the main source of fuel for muscles. After you eat, when insulin levels are high, excess glucose will be stored in the liver.
Why we need carbs:
The simplest form of carbohydrate is glucose.
- A universal fuel for most organs and tissues in our bodies.
- The only fuel source for our brains, red blood cells and a growing foetus, and is
- The main source of energy for our muscles during strenuous exercise.
Good carb, bad carb
The production of energy will be related to the type of carbs you are eating. Different types of carbohydrates will have a direct effect on your total energy supply. ENTER: Glycemic Index.
Fact: the effects that different foods have on blood sugar levels VARIES considerably
The Glycemic Index (GI) estimates how much each gram of carbohydrate in a food raises a person’s blood glucose level after eating. We record the glycemic index on a scale of 100. A High GI is classified in the range of 70 or higher, and includes foods such as: white bread, white rice, glucose, and potatoes. A low GI food is in the range of 55 or less, and includes: beans, whole grains such as rye, oat or barley, most vegetables and sweet fruits such as peaches, or strawberries.
The higher the glycemic index, the faster glucose is released into the bloodstream. A lower glycemic index would be linked to slower digestion, and lower insulin demand.
Health benefits of low GI foods:
Evidence and research all support the positive benefits of low GI foods:
- Help to fill you up and keep you feeling satisfied for longer, avoiding over eating or too much snacking.
- Lower your insulin levels which makes fat easier to burn and less likely to be stored.
- Help you to lose body fat and maintain lean muscle tissue.
- Reduce your triglycerides, total and ‘bad’ (LDL) cholesterol.
- Increase your levels of ‘good’ (HDL) cholesterol.
- Reduce your risk of developing type 2 diabetes.
- Help to manage your blood glucose levels and reduce your risk of developing diabetes complications.
- Reduce your risk of developing cardiovascular disease.
- Reduce your risk of developing some cancers
- Reduce your risk of developing certain eye diseases.
- Improve your skin
- Sustain your energy levels longer, improving both mental and physical performance.
When you consume carbohydrates, and what type you are eating will have a significant effect on your exercise performance.
What to do before a ride?
2-3 hours before the ride- Low-mid GI: rye bread or scrambled eggs
30 minutes before- Mid GI: banana
During the ride- Fast delivery of energy: High GI energy drinks, dried fruit such as raisins are great
After the ride- Fast recovery: Try cereal corn flakes or rice crispies (high GI) + milk (contains protein for the muscle recovery). Or try chocolate milk
2-3 hours post ride- Low GI: grilled salmon with steamed vegetables + sweet potato
Summary: A low-GI food will release glucose more slowly and steadily, which helps control blood glucose levels after a meal. A high-GI food leads to a faster increase in blood glucose levels, and is often needed for energy recovery after exercise.
When you are not cycling or working on energy recovery, try to incorporate low GI foods, or “smart carbs” into your meals