Exercise and an active lifestyle have many benefits to health. Conversely, a lack of exercise is detrimental to overall health and is specifically associated with several health problems. People with a history of heart disease or over the age of forty should consult a healthcare professional before starting an exercise program.
Health Problems Associated with a Sedentary Lifestyle
(The following list is comprehensive, although not necessarily exhaustive. Contact your health care professional for more information.)
Aerobic CapacityA sedentary lifestyle reduces the body's aerobic capacity, meaning that less exercise can be tolerated, and only at a lower level of intensity.
Benign Prostatic Hyperplasia (BPH)The prostate is a small gland that surrounds the neck of the bladder and urethra in men. Its major function is to contribute to seminal fluid. If the prostate enlarges or swells, it can put pressure on the urethra, acting like a partial clamp and causing urinary symptoms. This condition is known as benign prostatic hyperplasia (BPH). Men who are physically active have been reported to have a lower risk of BPH; the cause of this relationship is believed due to affects of exercise on parts of the nervous system.1
CancerCancer is a general term for more than 100 diseases that are characterized by uncontrolled, abnormal growth of cells. Cancer is the second leading cause of death in Americans. A sedentary lifestyle has been linked to cancers of the lung,2 colon, breast, and prostate,3 but evidence regarding protection against breast cancer remains somewhat inconsistent.4 Some effects of exercise in reducing cancer risks may be linked to how hormone levels are indirectly altered by physical activity.
Cardiovascular DiseaseCardiovascular disease is the number one cause of death in the United States. A sedentary lifestyle increases the risk of cardiovascular disease, while exercise increases protective HDL cholesterol,5 an effect that occurs even from walking.6 Exercisers have a relatively low risk of heart disease.7 People over forty years of age or who have heart disease should talk with their doctor before starting an exercise program; overdoing it can actually trigger heart attacks.8
Cholesterol (High)Although it is by no means the only major risk factor, elevated serum cholesterol is clearly associated with a high risk of heart disease. Exercise increases protective HDL cholesterol,9 an effect that occurs even from walking.10 Exercisers have a relatively low risk of heart disease.11 People over forty years of age or who have heart disease should talk with their doctor before starting an exercise program; overdoing it can actually trigger heart attacks.12
DiabetesPeople with diabetes cannot properly process glucose, a sugar the body uses for energy. As a result, glucose stays in the blood, causing blood glucose to rise. At the same time, however, the cells of the body can be starved for glucose. Diabetes can lead to poor wound healing, higher risk of infections, and many other problems involving the eyes, kidneys, nerves, and heart.
Exercise helps decrease body fat13 and improves insulin sensitivity.14 Exercisers are less likely to develop type 2, or noninsulin-dependent diabetes mellitus.15 People with type 1, or insulin-dependent diabetes mellitus, who exercise require less insulin.16 However, exercise can induce low blood sugar or even occasionally increased blood sugar.17 Therefore, diabetics should never begin an exercise program without consulting a healthcare professional.
FibromyalgiaFibromyalgia is a complex syndrome with no known cause or predictable cure. Its predominant symptom is severe muscle pain, although other symptoms such as fatigue, chest pain, low-grade fever, swollen lymph nodes, insomnia, frequent abdominal pain, irritable bowel syndrome, and depression, may also exist.18 Low-intensity exercise may improve fibromyalgia symptoms. Patients who exercise regularly have been reported to suffer less severe symptoms than those who remain sedentary.19,20,21
HypertensionHypertension is the medical term for high blood pressure. The cause of most hypertension remains unknown. Daily exercise can lower blood pressure significantly.22 A twelve-week program of Chinese T'ai Chi was reported to be almost as effective as aerobic exercise in lowering blood pressure in sedentary elderly people with high blood pressure.23
Immune FunctionThe immune system is an intricate network of specialized tissues, organs, cells, and chemicals that works to protect the body from invading microorganisms. Moderate exercise improves immune function,24 although excessive exercise has been reported to have a detrimental effect on immune function.25
MenopauseMenopause is the cessation of the monthly female menstrual cycle. Sedentary women are more likely to have moderate or severe hot flashes compared with women who exercise.26,27 In one trial, menopausal symptoms were reduced immediately after aerobic exercise.28
MortalityA clear association exists between a sedentary lifestyle and increased mortality (risk of death).29
ObesityA sedentary lifestyle greatly increases the likelihood of obesity.30
OsteoporosisPeople with osteoporosis have brittle bones, which increases the risk of bone fracture, particularly in the hip, spine, and wrist. Exercise is known to help protect against bone loss.31 The more weight-bearing exercise done by men and postmenopausal women, the greater their bone mass and the lower the risk of osteoporosis. Walking is sometimes considered the perfect weight-bearing exercise. For premenopausal women, exercise is also important, but taken to extreme, it can be overdone. Exercise so excessive that it leads to cessation of the menstrual cycle actually appears to contribute to osteoporosis.32
StrokeStrokes are caused either by a lack of blood supply to the brain or by hemorrhage within the brain. Depending on the area of the brain that is damaged, a stroke can cause coma, reversible or irreversible paralysis, speech problems, and dementia. Regular exercise has been linked to a lower risk of stroke incidence.33
1. Platz EA, Kawachi I, Rimm EB, et al. Physical activity and benign prostatic hyperplasia. Arch Intern Med 1998;158:2349-56.