5. For Those who Know They are Underweight or Want to Build Muscle

You may be underweight for various reasons –maybe you're recovering from illness or accident, maybe you have never really eaten very much, maybe you eat loads but just can't seem to keep on the pounds. Maybe you dieted to lose weight because you don't want the fat, but you now have difficulty making muscle.

Muscle is made from protein, and you need to eat protein to make it. You also need energy to make it, which comes from carbohydrate. But the main thing you need to make it is USE. The body won't make muscle if it thinks you don't need any! So you have to convince it, and that's what exercise is for.

People's main problem with exercise is that it's boring and repetitive. There are so many more interesting things you could be doing, like drinking or watching movies. We also associate exercise with losing weight because of course it burns off fat, so if you're underweight you may feel that exercise is the last thing you need to do!

If you look at how much many weightlifters weigh, this may change your mind. If you want to put on weight, your fastest way there is exercise with an adequate diet –for you this means starting with diet 1 above, and adding extra measures of protein and low GI carbs to every meal.

Swimming is one of the best ways to exercise without being bored, especially if you swim with a friend. Dancing is great –and you can do this alone if you're embarrassed. Martial arts are cool and build confidence and poise as well as muscle. Cycling saves you fuel money and gives you bigger muscles, so you win twice [plus these days, its cool to be green].

Playing with your kids, friends, or making love to your partner all counts as exercise too.

Finally, check section 3 above to make sure you don't have any vitamin or mineral deficiencies that could lead to loss of weight or lack of muscle, joint pains or other physical problems that may put you off exercise. Lack of nutrients will make it difficult for your body to build muscle.

If you really want to look like Arnie, use the next section.