The Checkup: Exercise Helps Cells Clean House

A fascinating study may have hit on how, on a cellular level, exercise helps keep you healthy.

• If tenth grade biology taught you anything, it’s that cells are like tiny ecosystems. But did you know that part of that ecosystem is a pretty neat trash-collection mechanism by which cells can remove—and reuse for energy—their own waste? Researchers recently learned that this cell function, called autophagy, gets a boost from exercise, allowing cells to eradicate waste more quickly and efficiently. The finding could provide an underlying reason for why exercise makes you so healthy: you’re able to get rid of the bad stuff more easily than the next guy. And it could offer new avenues for tackling various diseases and age-related conditions. Here’s why, according to the New York Times:

Without [autophagy], cells could become choked with trash and malfunction or die. In recent years, some scientists have begun to suspect that faulty autophagy mechanisms contribute to the development of a range of diseases, including diabetes, muscular dystrophy, Alzheimer’s and cancer. The slowing of autophagy as we reach middle age is also believed to play a role in aging.

Read more here.

• Remember secondhand smoke? Yeah. It’s still a big problem for teens.

• A recent national survey quantifying the bikeability and walkability of major U.S. cities found Philly to have the eighth highest rate of citizens who walk or bike to work, with 1.6 percent arriving to the office on two wheels and 8.4 percent on foot. Philly ranks 14th out of 51 cities on a list of the safest places to bike, and 9th out of 51 for safest cities for walking. And we’re among the top three cities ranked highest for miles of bike lanes per square mile. Read more here.