Apart from the very obvious changes to your shape during pregnancy, your body undergoes other changes, many of which you should be aware during pregnancy.
Raised hormone levels
Your body experiences numerous hormonal changes, some of which influence the way you exercise; three hormones are most relevant to exercise – relaxin, oestrogen and progesterone.
Relaxin softens the connective tissue in joints and muscles enabling the pelvis to widen for delivery and the abdominals and pelvic floor muscles to stretch.
Oestrogen is the growth hormone. It causes your breasts to enlarge and increases the size and strength of your heart. It also encourages water retention.
Progesterone relaxes the walls of the blood vessels, to enable them to cope with the increased volume of blood. It also increases your body temperature
It is important to take account of these hormonal changes when you work out. Exercises that were previously easy may become inappropriate now that you’re pregnant.
- When your body weight is forward and supported on your hands and knees (kneeling on all fours), you may experience a tingling sensation or a numbness in your fingers; this is due to water retention.You may also get heartburn when in this position, which is due to the effects of progesterone on your digestive system.
- Your ankles may become swollen, which will make it uncomfortable to wear trainers for any length of time. This footwear is recommended for the aerobic section, but can be removed for other sections. Swollen ankles may be due to water retention, but they can also indicate raised blood pressure, so you should check this before continuing.
- Reduced joint stability, due to relaxin may increase the risk of injury. Your pelvis and spine are particularly vulnerable due to the forward pull of your baby and decreased support from your stretched abdominals, so correct posture and good exercise technique are vital. Avoid high-impact or bouncy movements as they increase the stress to your joints, breasts and pelvic floor.
- You will feel warmer quickly because your body temperature is already raised due to progesterone. You should avoid getting too hot and must always exercise in a well-ventilated room
- During the aerobic section, keep your legs moving to assist the return of blood back to the heart. If you stop suddenly you may feel dizzy due to the influence of progesterone dilating the walls of your blood vessels.