Physical activity and your diet

Introduction

We are all becoming more aware of the physiological and psychological rewards of being physically active. If you need to lose weight or want to avoid becoming overweight, then the best way is to increase your physical activity levels, and to reduce your dietary fat intake, which can be achieved by increasing your intake of starchy and sugary carbohydrates. Even if you didn’t lose weight, but became fitter, it would help you avoid the many health complications of being overweight and so increase your life quality and expectancy. Furthermore, taking part in regular physical activity also helps reduce your risk of developing heart disease, diabetes, osteoporosis and certain forms of cancer. And, not forgetting the important role that physical activity plays in your mental well-being.

So, the recommendation that everyone should accumulate 30 minutes or more of physical activity over the course of most days of the week is thoroughly justified. But how do we go about becoming more active? If you’re pretty sedentary at the moment, then what you need to do is to modify your lifestyle to build in more physical activity. So start by becoming less sedentary, for example decreasing the time you spend watching television, surfing the net or playing computer games. Next try to be more active, take the stairs instead of the lift, park further away from the supermarket, or get off the bus one stop earlier and walk the rest of the way. Then gradually add some sustained exercise to your daily routine, such as brisk walking, cycling or swimming. Yes, the aim is to be doing at least 30 minutes of continuous exercise five days per week, but gradual is the key, so try three lots of ten minutes to start with, and take it from there. The next question is - how do we fuel these bursts of energy?

Dietary Considerations

The dietary considerations for fuelling a healthy active lifestyle can be found in more detail in the following sections, but here are the basics: As we know, a healthy balanced diet is essential for good health. The key to making our diet healthy and balanced is simply everything in moderation, plus extra carbohydrates if you’re exercising. But why the emphasis on carbohydrates? Well, no matter what type of exercise you do, your body will always use some glucose for energy. Glucose is formed from the breakdown of carbohydrates – the sugars and starches in your diet - and is stored as glycogen. However, the body can only store a limited amount of glycogen, so the stores need to be kept topped-up to avoid fatigue. If you don’t eat enough carbohydrates, but continue to exercise you will soon become sluggish and dizzy and your exercise goals will go right out the window!

The more physical activity you do, the more glucose your body uses, the more carbohydrates you need to consume to replenish your stores. Therefore, physically active people need to consume a diet where more than half of it comes from carbohydrate foods. The bulk of your carbohydrate intake should come from the starchy sources such as bread, rice, potatoes and pasta and the remaining from more sugary sources such as sugar, fruit and juices. However, as most carbohydrate foods, for example pasta or sugars, are eventually broken down into glucose, one type is not necessarily better than the other. But, if you’re exercising regularly you need to eat a lot of carbohydrates, and there is only so much bread and pasta you can eat, so this is where sugary snacks and drinks have a useful role to play, both in providing you with energy before you exercise, and in helping you restock your glucose stores after exercise ready for your next bout of physical activity.

Although you need to allow two to three hours after a large meal before exercising, a high carbohydrate snack within 30 minutes of training has several benefits. Eating 25-50 grams of rapidly absorbed carbohydrate just before exercise will not only improve performance, but will also help maintain your blood sugar levels and so prevent you feeling light-headed. There are plenty of portable high carbohydrate snacks to choose from - bagels, honey or jam sandwiches, cereal bars, bananas, watermelon, dried fruit, Jaffa cakes, jelly beans, Liquorice Allsorts, juice or a sports drink – so find something you fancy.