Optimum Nutrition for Sport

Sports nutritionist Jacky Hems, answers your questions.
Sports nutrition has changed in recent years and the days of carbohydrate-loading for endurance sports and high-protein diets for strength/resistance exercise is being replaced with the recognition of the need for a more balanced approach in both types of exercise. Many of the principles of good health and optimum nutrition can be applied to sports nutrition. The key additional element is adjusting these to achieve maximum performance, regardless of the level you are at when it comes to fitness and exercise. You may find that some of these adjustments conflict with what you have come to understand about healthy eating, particularly around the consumption of carbohydrates and insulin release. However, I will explain why these adjustments are important and help you to achieve the maximum benefits from your exercise programme. The requirements for sports nutrition will vary from person to person depending on the type, intensity and frequency of sport/exercise you do, your personal goals and biochemical individuality. So the following answers to our most frequently asked questions are based on general principles, with some examples to give you more guidance.

When and what to eat before and after exercise.
As well as knowing what and how much to eat, one of the most powerful differences you can make to your training regime is knowing ‘when’ to eat around your programme. Two of the leading authors on this subject are Ivy and Portman and in their book Nutrient Timing: the Future of Sports Nutrition (1) they describe three key nutrient timing phases – the Energy, Anabolic and Growth Phases. These are primarily focused on strength training but with a few adaptations can be applied to endurance training. Understanding the role of some key hormones released during and after exercise is important, as it alters what is best to eat, and when.

The Energy Phase – during a workout
This covers the period of a workout. During this ‘catabolic’ phase, when you are burning a high amount of energy, the main objective is to spare muscle glycogen (which is the muscle’s energy reserve) and protein to help reduce muscle fatigue and damage and enable faster recovery post-workout. If you’re exercising for an hour or more (e.g. intense strength training, marathon, triathlon, cycling), at around 10-20 minutes before you start have a drink/gel consisting of 30-60g high GI carbohydrate (glucose, sucrose or maltodextrin – fructose can cause digestive problems for some people) and add around one third of that amount whey protein (see Benefits of Whey Protein below for alternatives) for strength training. During exercise, for both strength and endurance training, continue with a ratio of around 3:1 carbohydrate to protein per hour of exercise (if you’re exercising for less time than this you shouldn’t need to supplement), with added electrolyte rehydration salts, vitamins C and E and magnesium. The amounts needed vary from person to person depending on the duration of your workout and your caloric needs. The following amounts are recommended by Ivy and Portman (1) High GI carbohydrate 20-26g Whey protein 5-6g Leucine 1g Vitamin C

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