Although sleeping is an instinctive activity, there are some sleep positions that are more helpful than others. If you're resting in an improper position for six to eight hours each night, you may not be getting the quality of sleep you need. A good sleep position can help you awake feeling more refreshed, energetic, and ready to face the activities of the day.

There are four general sleep positions: sleeping on your back, sleeping on your stomach, sleeping on your right side, and sleeping on your left side. Most people tend to favor one position over the others, but it's common to change sleep positions several times throughout the night. Forcing yourself to adapt a different sleep position can be tricky, but the task is often easier if you use a series of pillows to prop your body up into the correct position before bedtime.

If you suffer from back pain, the best sleeping position is on your side in the fetal position. Keep your knees bent and place a pillow between your legs to take the stress off your back. Avoid sleeping on your stomach, since this position can cause strain by exaggerating the arch at the base of your spine. If you must sleep on your back, use a pillow to prop your legs up slightly and help align your spine.

For pregnant women, the best sleep posture is lying on the left side. This position will increase the amount of blood and nutrients reaching the placenta. Pregnant women should avoid sleeping on their backs or stomachs, since these sleep positions can aggravate back pain, heartburn, and shortness of breath.

While research indicates sleeping on your stomach is the least popular sleep position, it can be beneficial in certain cases. For example, people suffering from degenerative disc disease often find sleeping on their stomach helps to reduce pressure on the disc space. This position works best on a firm mattress, however.

To reduce the risk of Sudden Infant Death Syndrome (SIDS), infants should always be placed on their backs to sleep. Experts aren't exactly sure why stomach sleeping leads to an increase in SIDS, but some possible reasons include increases in body heat, the obstruction of the child's airway by bedding, or a buildup in carbon dioxide. However, once your baby is able to roll over and lift his/her head up, the risk of SIDS is greatly reduced regardless of what sleep position your baby uses.