Is Exercise the Magic Pill?
December 04 2011
This was the title of the presentation I gave a week back. If you know anyone who doesn't exercise, send this to them please. Everyone kind of vaguely knows that exercise is important, but they got no clue about the breadth and depth of the benefits we are talking about.
Heart Disease: Heart disease is the leading cause of death in United States. Almost 300,000 people die of heart disease every year. In short, 1 out of 3 people would die of heart disease.
Exercise Beneifts: Number of observational studies have shown exercise to cut the risk of heart disease and the risk of deaths from heart disease by almsot 50%. Exercise capacity has shown to be a stronger predictor of death than established risk factors such as hypertension, smoking, and diabetes. As shown in the graph, it is now clear that as your physical fitness (exercise capacity) increases, the risk of dying decreases in a dose-response manner in both healthy and people with heart problems(1,2).
Cancer: Cancer is the second leading cause of death in USA. 1 out of 4 people would die of Cancer. 1 out of 8 women will be diagnosed with breast cancer.
Exercise Benefits: There is strong evidence to show that exercise may decrease the risk of colon cancer by almost 50% and breast cancer by about 30% from observational studies. Colon cancer is the most common form cancer in both men & women. And there some evidence to suggest that exercise lowers the risk of endometrial, lung and prostate cancer. Exercise has shown to lowers the risk of cancer recurrence or death in colon, prostate and breast cancer survivors too. It also improves the quality of life and lowers fatigue in cancer patients(3).
Diabetes: Diabetes is the 7th leading cause of death in the states. 1 out of 13 people would die of diabetes. Diabetes is the leading cause of amputations in the country.
Exercise Benefits: Number of observational studies & experimental studies have shown to cut the risk of diabetes by almost 60%. Exercise is also beneficial for treating diabetes. The famous study - Diabetes Prevention Trial - showed that exercise and diet cuts the risk of diabetes by almost 60% compared to the most popular diabetic drug- Metformin, whiich showed a 30% reduction(4).
Osteoporosis: Osteoporosis is the loss of bone density which can lead to bone fractures. 1 out 5 women over the age of 50 will develop osteoporosis. 1 In 5 women over the age of 75 who sustains a hip fracture will die within the next 2 years. Half of the survivors will end up dependent on others.
Exercise Benefits: Exercise, especially weight bearing exercises can be beneficial to prevent and treat osteoporosis bone density. It seems like we need more high quality studies to quantify the effect of exercise on osteoporosis.
Cognition: Cognition is just a big word for mental processes like memory, learning, attention and so forth. Recently, there has been an intense interest in the benefits of exercise on brain cognition.
- Children: There is a growing body of studies that show a positive relationship between exercise and cognition and children. Exercise has shown to have a positive relation to cognition in 8 cognitive measurement categories (math test, verbal test, memory, academic readiness, perceptual skills, IQ and achievement) except for memory for all age groups.
- Exercise has also shown to improve academic performance. A few studies have shown no change in academic performance with exercise. But none of the studies have shown a decline in academic performance by increasing the time allotted to exercise. The below graph shows a significant improvement in academic scores with exercise in elementary school children after 3 years compared to a control group. This is ironical considering physcial education is the first to be cut from the curriculum owing to financial constraints.
- Older Adults: Now there is an overwhelming number of studies to show that exercise is important for maintaining brain functions with age and also in lowering risk for cognitive decline and dementia.The greatest improvement is seen with executive cognition function which involves tasks such as planning, scheduling, inhibition, and working memory. In fact, executive cognitive processes suffer the most with ageing (5,6,7).
Depression: 1in 10 adults are affected by depression. Women are almost 70% more likely than men to suffer depression. Half of the deaths due to suicides is attributed to depression.
Exercise Benefits:There are 2 studies which show that exercise is as effective as anti-depressant drugs in reducing depression in people with mild to severe depression. The study also showed that exercise reduces the chances of the depression returning. After 6 months, only 8% in the exercise group relapsed compared to 30% in the drug group. It is safe to say that evidence is only suggestive and we need better quality studies to show a conclusive evidence of exercise for depression (8,9).
Side Effects: The side effects of exercise are almost zero, if done properly and gradually. It is typical for doctors to carefully evaluate to see if the side effects of the drug exceed the benefits of the drug. Just like exercise, aspirin works well to prevent heart attacks, but the side effect is cerebral bleeding.
I didn't really talk about the effects of exercise on obesity, treating pain, and preventing the loss of muscle mass since most people are aware of it. I also talked a bit about the minimum exercise required for achieving these benefits. Exercise research is still in its infancy; there will be more and more studies looking at the effect of exercise on other health conditions in the coming years.
Conclusion
Is there any pill out there which can prevent and/or treat so many major diseases, improve quality of life, has almost zero side effects, and costs almost nothing?
One hand went up in the crowd. A bit perplexed, I asked, “which drug is that?”
She said, 'exercise' - with a smile.
Reference 1 | Reference 2 | Reference 3 | Reference 4 | Reference 5
Reference 6 | Reference 7 | Reference 8 | Reference 9
