You may want to think twice before taking a dip. 

By Brigitt Earley
Updated May 18, 2016
Staying active is a vital part of aging well. The average woman can lose 23 percent of her muscle mass between ages of 30 and 70, says Fabio Comana, a faculty instructor at the National Academy of Sports Medicine. You lose muscle more rapidly as you age, but exercise—resistance workouts in particular—can increase mass and strength, even well into your 90s, says Comana. Staying fit may also reduce age-related memory loss, according to a study published in the journal Frontiers in Aging Neuroscience. Plus, Alzheimer’s disease accounts for approximately 60 to 70 percent of all dementia cases, says Comana, adding that increasing physical activity can decrease this statistic by 25 percent. That’s because exercise strengthens the hippocampus, the region of the brain associated with learning.
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A dip in the pool provides a welcome chill on a hot summer day, but a new study suggests that refreshing water might not be so clean, despite disinfectants like chlorine.

Whether you’re diving into a public swimming pool or a personal hot tub, there will be pathogens present. Disinfectants, such as chlorine, help to kill those pathogens. But the disinfectants also react with sweat, urine, and other substances that swimmers leave behind, according to the study published in the American Chemical Society journal Environmental Science & Technology. These reactions cause compounds scientists call disinfection byproducts.

In lab settings, testing has shown that these byproducts can cause genetic damage to cells. Other studies suggest those who frequently swim or work in and around pools could be more likely to have certain health problems, such as bladder cancer and respiratory issues.

During the study, researchers sampled water from both public and private pools and hot tubs, after both normal and excessive use. More than 100 disinfection byproducts were identified and tested to determine potential damage to cells. Pool samples were 2.4 times more likely to damage cells than the tap water used to fill them. Hot tub samples were 4.1 times more likely to damage cells.

Swimmers can do their part to keep pool and hot tub water cleaner by showering before taking a dip and using toilets when needed. Pool owners and operators can clean facilities and change the water more frequently to reduce the amount of potentially harmful disinfection byproducts in the water. Check out these five smart tips for staying safe in public pools.