Doctors often recommend walking as the safest form of aerobic exercise for pregnant women. Women who are habitual walkers are usually urged to continue walking during their pregnancy. Those who have been sedentary are often advised to start a walking program.
And those who are accustomed to running may be advised to switch to walking during their pregnancy, to avoid excessive fatigue, breathlessness, and additional stress on the bones and joints. (Hormonal changes in pregnancy tend to loosen ligaments all over the body in preparation for childbirth. As a result, the joints become more susceptible to injury.)
While weight reduction should not be attempted during pregnancy, walking can help to prevent excessive weight gain. By increasing circulation, walking can also help guard against the development of varicose veins and edema (swelling in the legs and ankles). And walking may help alleviate the sway-backed posture (called lordosis) that pregnant women can sometimes develop.
With her doctor's okay, a new mother can resume her walking routine within a few days after delivery.
One of the biggest problems with strenuous, fitness-boosting exercise is the risk of injury. Although the injury itself may heal in a fairly short time, the damage it does to your motivation and enthusiasm can be longlasting. Fortunately, a walking program can help you increase your fitness with a relatively small risk of injury.
By definition, walking means keeping one foot on the ground at all times. Therefore, compared to jogging, which involves a free-flight phase, walking poses much less danger of falling. And according to Kevin Campbell, Ph.D., a staff scientist at the Cleveland Clinic
Foundation, during walking, each foot hits the ground with a force of only one-and-a-quarter times the weight of the body. In contrast, each running stride lands with a force of up to four times the body weight.
Such high forces on the feet carry stress up the body to the ankle, knee, and hip joints. One study used an artificial hip implant to measure the internal pressure placed on the hip joints during exercise. The stress associated with jogging was one-and-a-half times greater than that found with walking.
This explains why so many runners suffer injuries to these joints. In contrast, the lack of these injuries is considered one main reason why walkers are better able to stick with their exercise programs.
In the 1980s, Dr. Pollock discovered that 22 70-year-old people were able to gradually work up to a program of brisk walking with no adverse consequences to either their hearts or their joints. However, when 18 of the subjects then graduated to a program of jogging and jog/walking, 60 percent of them suffered significant injuries. "It was not a cardiovascular limitation, but an orthopedic problem," he stresses.
A regular walking program may even help older adults avoid injury -- by keeping them on their feet. For adults over 70 years old, the incidence of injury linked to falls is higher than for any other age group. The neuromuscular changes that occur in aging tend to disturb the sense of balance, which in turn raises the risk of falling and of injury. (Other factors, including medication and osteoporosis, also play a role in the high incidence of injury.)
However, participation in a walking program has been shown to improve balance, thereby reducing the risk of falling among older adults.
A well-designed walking program can help anyone achieve higher levels of fitness. Walking can help improve body composition by increasing your body's ratio of muscle to fat. It can help you boost your endurance and increase the strength of the muscles in your lower body. A walking program that includes plenty of stretching exercises can help you maintain flexibility.
And, perhaps most importantly, walking can help you increase your aerobic capacity and build a better heart.
To learn more about walking, see:
Peggy Norwood Keating, MA, Contributing consultant
Rebecca Hughes, Contributing writer