Health Smart Watchh

Let's be honest: most of us stay healthy to look and feel good. This is very good! But fortunately for runners, walkers and other sports enthusiasts, physical activity can also offer some well-known long-term benefits, including a longer life span, a stronger heart and a lower risk of type 2 diabetes."Physical activity contributes to overall health and longevity," said Dr. Alpa Patel, a cancer epidemiologist and director of the American Cancer Society's Cancer Prevention Research-3 strategy. "Doing something from scratch is where we see the biggest benefits. The more you can do, the better."

Still don't like to work out? Here are three deep reasons why exercise comes first.

1. Strengthen your memory

The benefits of high-intensity interval training (HIIT) are growing. A new study from Master University found that HIIT training three times a week for 20 minutes each time for six weeks resulted in significant improvements in high-interference memory among study participants. That memory could help you find your car in a crowded parking lot, according to Jennifer Hayes, PhD, lead author of the study and assistant professor in the department of kinesiology at McMaster University.

While researchers aren't entirely sure why high-intensity exercise helps boost memory, they suspect that the rush of adrenaline during HIIT helps the brain focus. High-intensity exercise also produces more brain-derived neurotrophic factor (BDNF), which supports the growth of new brain cells.

Nervous about an all-out workout? Haizi points out that high-intensity exercise doesn't have to be painful to be effective. Participants in the study cycled intensely for one minute, followed by an easy one-minute ride 10 times.

2. Reduce your risk of cancer

Here's the good news for those who are overweight: Even if you don't lose weight, physical activity can significantly reduce your risk of breast, colon and endometrial cancers, Patel says. "Achieving an optimal weight is a very difficult task for many people," Dr. Patel said. "But the good news about physical activity is that there are some serious health benefits even without weight loss."

To reap these benefits, the American Cancer Society recommends that you exercise at least 30 minutes a day, five days a week. Moderate intensity was defined as 3 miles per hour, or 20 minutes per mile.

3. Help protect your eyesight

"More is better" was also the result of a UCLA study on the role of exercise in preventing glaucoma. Glaucoma is one of the leading causes of blindness in the United States.

In the study, researchers examined the relationship between daily walking speed and number of steps and glaucoma risk and found that the most active adults were 73 percent less likely than the least active to develop the visually impaired disease.

"Our study suggests that not only exercise behavior may be associated with reduced glaucoma risk, but that people who move at a faster pace, take more steps or run may even reduce their glaucoma risk even further compared to people who move at a slower pace and take fewer steps," said Dr. Victoria L. Zeng, the lead author of the study.