Preparing for a Marathon: The Nutrition Factor
Optimum nutritional habits are essential during your marathon training. Fundamental components include hydration status, carbohydrate and protein intake as well as electrolyte repletion, and joint health. To ensure proper muscle recovery post-exercise and to reduce your risk of injury, consider the following points:
Restore electrolytes and water (essential electrolytes being: sodium, potassium, magnesium) in the form of a sports re-hydration drink. Electrolyte repletion is essential as minerals such as sodium, potassium and magnesium promotes post-exercise recovery while ingredients such as citric acid and malic acid are essential factors required for energy production. Drinking plenty of water before during and after your run will prevent dehydration as well as overheating, both of which may lead to nausea and lightheadedness. It is recommended to drink about 150-200 milliliters every 15 minutes during your training but take into consideration the daily temperature and intensity of your run.
Replenish glycogen (glucose stores) rapidly to promote muscle/protein rebuilding; research indicates a 4:1 carbohydrate to protein ratio optimizes glycogen replenishment and enhances aerobic endurance performance by 24%. Carbohydrate is the most efficient source of energy and endurance athletes maintain a high carbohydrate diet. Carbohydrate-rich foods include pasta, rice, bread, crackers and bagels. While carbohydrate loading is great for providing energy for the race, remember to include some protein to provide the building blocks for muscle. Protein sources include fish, chicken, legumes and dairy.
Reduce muscle injury and oxidative stress with antioxidants like Vitamin C. Antioxidants such as vitamin C are essential for both muscle energy and recovery as well as for immune support during physical stress and exercise. In general, endurance athletes are more susceptible to infections especially after heavy or prolonged exercise. This susceptibility is often up to 72 hours after a marathon. Immunity can also be supported by ensuring adequate intake of amino acids like L-glutamine which is the primary source of fuel for the cells in the intestinal tract. Protecting the integrity of this lining is important as components within the intestinal tract make up about 60% of your immune system, known as the mucosal-associated lymphoid tissue (MALT) or the gut-associated lymphoid tissue (GALT).
Last but certainly not least, we must remember to support our musculoskeletal system which includes our bones, muscles, ligaments, tendons and cartilage. Without a healthy musculoskeletal system, endurance athletes are often prone to injury and or debilitating pain. For example, weak tendons and ligaments may contribute to structural instability and spinal misalignment. Nourishing the various tissues with nutritional supplements like glucosamine and chondroitin sulfate as well as zinc, manganese and silica support the ability of these tissues to heal and prolong their vitality. In addition, maintaining a healthy diet with essential fatty acids like fish oil or flax seed oil can not only reduce inflammation but also provide the nourishment for cells to maintain their optimal health status.
In essence, maintaining a healthy balanced diet with adequate rest in between your runs will help prevent injury, reduce muscle recovery time and allow you to meet your marathon goals with confidence.
Best food choices for energy
Carbohydrate (CHO) is the most efficient form of energy and all athletes are recommended to follow a high carbohydrate diet. Carbohydrate-rich foods include bread, crackers and bagels; pasta, noodles, rice and couscous; breakfast cereals; fruit and milk.
The longer you spend training the more carbohydrate you need. The table below will help you calculate your daily carbohydrate needs.
Duration of Training CHO needs
1-2 hours/day – 6-7g CHO/Kg body weight/day
2-4 hours/day – 7-8g CHO/Kg body weight/day
4+ hours/day – 8-10g CHO/Kg body weight/day