Lee Rodwell reports on the importance of fitness before and during pregnancy
If you are thinking of having a baby you need to get in good shape - both physically and mentally. This means making time for exercise and learning how to relax.

The fitter you are, the better placed you will be to cope with the demands of pregnancy and childbirth - and to get back into shape after your baby is born.

However, learning to relax quickly and effectively is equally important. Not only will it help you cope with the stresses that can come with pregnancy, it can help you conserve energy during labour and relieve any stress and anxiety that might slow the birth down.

As part of your pre-pregnancy planning you should be aiming to build up to half an hour of moderate intensity physical exercise on five days of the week. Research indicates that this is the level of activity which significantly improves health.

Once you are pregnant, you can keep up your normal daily physical activity and continue most sports and exercise routines as long as you feel comfortable, you are in good health and have no previous history of miscarriage or premature labour.

If you were not very active before your pregnancy, don't suddenly take up any strenuous exercise. If you are not sure whether it is wise to do something or not, check with your doctor or midwife.

Swimming may be the perfect form of exercise for you in pregnancy. Not only is it one of the best all-round types of exercise, but the water helps to support your increasing weight.

Even if you can't swim, you can sign up for water exercise classes for pregnant women. Water exercise can gently tone your muscles, help improve flexibility and build up your strength.

Relaxation techniques are usually taught at antenatal classes, but a simple method is suggested below on the left.

Before you get pregnant

Make changes gradually. Aim to be a little more active every week as your strength and stamina increase.

t Small lifestyle changes can increase your fitness as part of your everyday routine: use the stairs instead of the lift; walk up escalators; walk to the next bus stop; leave the car at home.

t Take up a new interest: swimming, tennis, cycling, dancing. Choose something you enjoy and which fits into your lifestyle - that way you will be more likely to stick to it.

t If you do go to classes, make sure the instructor is properly qualified.

t Don't overdo it - women who exercise excessively often find that their periods stop altogether.

t Everyday activities can be a good way of keeping fit so keep up your gardening or household routines.

Once you are pregnant

t Try to keep active every day. If you can't manage that, any amount is better than nothing.

t Whatever form of exercise you choose, start gradually and slow down comfortably. Never go on until you feel exhausted and always stop if you feel any pain.

t Make sure you drink plenty of fluids.

t Avoid any strenuous exercise in hot weather.

t If you go to any kind of exercise classes, check your teacher is properly qualified and knows about your pregnancy?

After the birth

t In the early weeks, rest and relaxation are as vital as exercise, so be sensible to start with.

t Keep up the postnatal exercises you were shown in hospital or by your midwife or physiotherapist.

t Do your abdominal exercises to strengthen, firm and flatten your tummy three-or-four times a day.

t Do your pelvic floor exercises religiously.

t Try to fit in a walk in the fresh air with your baby.

t Never exercise until you are exhausted or in pain. Stop if you feel dizzy, sick or faint.

Pelvic floor exercises

The pelvic floor muscles support everything within the pelvic cavity, including the uterus, the bladder and the rectum. During pregnancy, the pelvic floor is under extra stress so it is important to exercise these muscles before, during and after pregnancy, several times a day.

Basic exercise: Tighten your back passage and then draw in your vagina as if you were gripping a tampon, and your urethra as if you were trying to stop a flow of urine.

Hold briefly, then relax. Then repeat this quick movement more slowly.

Now start mentally counting as you squeeze and lift. Then go on squeezing and lifting, only harder (still counting), then again. Then relax.

If you can't manage this to a count of 10, do it for as long as you can. Try to do five-to-10 slow pull-ups, followed by five-to-10 fast ones, as a set several times a day.