"Talking on cell phones or reading while exercising can cause nerve strain in the head and neck.
"There is evidence that some activities, such as singing or exercising, can make mood-lifting hormones," explains clinical psychologist Dr Polly Fitch.
"Following a healthy diet and keeping your weight down and exercising can have major benefits," said Dr. Judith E. Fradkin, director of the division of diabetes, endocrinology and metabolic diseases at the National Institutes of Health.
For patients like Dr. Kreindel, the treadmill test, measuring how quickly his heart rate falls after he stops exercising, can help answer the question, to treat or not to treat?
As Mary T. Bassett, a New York City deputy health commissioner, said to me, public health campaigns that tell people to "just say no" to smoking, or to change their diets and start exercising, can be cruel if they are indifferent to neighborhood circumstances.
It's no secret that exercising can help you age gracefully by keeping you fit.
Advice on exercising can appear confusing - one recent report suggested that intensive training may be as bad as not jogging at all.
But other studies suggest that making healthful life changes, such as reducing stress and exercising, can slow down the rate of telomere loss.
Fitness experts and dietitians say what you eat directly before exercising can have a huge impact on your performance and your ability to endure a challenging session.
We know that exercising can make us uncomfortable.
Besides helping with your looks, exercising can help with creativity, cognition, your longevity, and much more.
