Exercise ‘as good as medicines’ in treating heart disease
Exercise may be just as good as medication to treat heart disease and should be included as a comparison when new drugs are being developed and tested, scientists said on Wednesday.
In a large review published in the British Medical Journal, researchers from Britain’s London School of Economics and Harvard and Stanford universities in the United States found no statistically detectable differences between exercise and drugs for patients with coronary heart disease or prediabetes, when a person shows symptoms that may develop into full-blown diabetes.
For patients recovering from stroke, the review - which analyzed the results of 305 studies covering almost 340,000 participants - found that exercise was more effective than drug treatment.
Cardiovascular disease is the world’s number one killer, leading to at least 17 million deaths a year.
“In cases where drug options provide only modest benefit, patients deserve to understand the relative impact that physical activity might have on their condition,” the researchers wrote.
The review also said the amount of trial evidence on the health benefits of exercise is considerably smaller than that on drugs, which the scientists said may have had an impact on their results.
What Type of Exercise Is Best?
Exercise can be divided into three basic types:
Stretching or the slow lengthening of the muscles. Stretching the arms and legs before and after exercising helps prepare the muscles for activity and helps prevent injury and muscle strain. Regular stretching also increases your range of motion and flexibility.
Cardiovascular or aerobic is steady physical activity using large muscle groups. This type of exercise strengthens the heart and lungs and improves the body’s ability to use oxygen. Aerobic exercise has the most benefits for your heart. Over time, aerobic exercise can help decrease your heart rate and blood pressure and improve your breathing (since your heart won’t have to work as hard during exercise).
Strengthening exercises are repeated muscle contractions (tightening) until the muscle becomes tired. For people with heart failure, many strengthening exercises are not recommended (see below).
They argued that this “blind spot” over exercise in scientific evidence “prevents prescribers and their patients from understanding the clinical circumstances where drugs might provide only modest improvement but exercise could yield more profound or sustainable gains”.
The review adds to a large body of evidence showing that regular exercise is key to human health.
According to the Geneva-based World Health Organization (WHO), physical inactivity is the fourth leading risk factor for global mortality, causing an estimated 3.2 million deaths around the world each year.
Over the past 4 decades, numerous scientific reports have examined the relationships between physical activity, physical fitness, and cardiovascular health. Expert panels, convened by organizations such as the Centers for Disease Control and Prevention (CDC), the American College of Sports Medicine (ACSM), and the American Heart Association (AHA), along with the 1996 US Surgeon General’s Report on Physical Activity and Health, reinforced scientific evidence linking regular physical activity to various measures of cardiovascular health. The prevailing view in these reports is that more active or fit individuals tend to develop less coronary heart disease (CHD) than their sedentary counterparts. If CHD develops in active or fit individuals, it occurs at a later age and tends to be less severe.
As many as 250 000 deaths per year in the United States are attributable to a lack of regular physical activity. In addition, studies that followed large groups of individuals for many years have documented the protective effects of physical activity for a number of noncardiovascular chronic diseases, such as non–insulin-dependent diabetes, hypertension, osteoporosis, and colon cancer. In contrast, we see a higher rate of cardiovascular events and a higher death rate in those individuals with low levels of physical fitness. Even midlife increases in physical activity, through change in occupation or recreational activities, are associated with a decrease in mortality. Despite this evidence, however, the vast majority of adults in the United States remains effectively sedentary; less than one-third of Americans meets the minimal recommendations for activity as outlined by the CDC, ACSM, and AHA expert panels.
The WHO says regular moderate intensity physical activity - such as walking, cycling or participating in sports - can reduce the risk of cardiovascular diseases, diabetes, colon and breast cancer, and depression, as well as cutting the risk of bone fractures and helping to control body weight.
In the United States, where health experts estimate half of adults will be obese by 2030 unless lifestyle habits change, the Centers for Disease Control and Prevention says less than 48 percent of adults exercise enough to improve their health.
Benefits of Regular Exercise on Cardiovascular Risk Factors
Increase in exercise tolerance
Reduction in body weight
Reduction in blood pressure
Reduction in bad (LDL and total) cholesterol
Increase in good (HDL) cholesterol
Increase in insulin sensitivity
There are a number of physiological benefits of exercise; 2 examples are improvements in muscular function and strength and improvement in the body’s ability to take in and use oxygen (maximal oxygen consumption or aerobic capacity). As one’s ability to transport and use oxygen improves, regular daily activities can be performed with less fatigue. This is particularly important for patients with cardiovascular disease, whose exercise capacity is typically lower than that of healthy individuals. There is also evidence that exercise training improves the capacity of the blood vessels to dilate in response to exercise or hormones, consistent with better vascular wall function and an improved ability to provide oxygen to the muscles during exercise. Studies measuring muscular strength and flexibility before and after exercise programs suggest that there are improvements in bone health and ability to perform daily activities, as well as a lower likelihood of developing back pain and of disability, particularly in older age groups.
Patients with newly diagnosed heart disease who participate in an exercise program report an earlier return to work and improvements in other measures of quality of life, such as more self-confidence, lower stress, and less anxiety. Importantly, by combining controlled studies, researchers have found that for heart attack patients who participated in a formal exercise program, the death rate is reduced by 20% to 25%. This is strong evidence in support of physical activity for patients with heart disease. Although the benefits of exercise are unquestionable, it should be noted that exercise programs alone for patients with heart disease have not convincingly shown improvement in the heart’s pumping ability or the diameter of the coronary vessels that supply oxygen to the heart muscle.
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By Kate Kelland