If 50 is the new 30, then who’s to say 70 isn’t the new 50?

Some older adults live that out every day. Go to any marathon on the weekend and you’ll see men and women in their 70s and 80s crossing the finish line. They’re playing golf with friends, gardening, volunteering at the local animal shelter or caring for grandchildren.

Staying in touch with friends through social media can aid cancer treatment.

Others, though, have a hard time just getting to the grocery store. Maybe the effects of illness or medications slow them down.

But does it matter whether older adults go out with friends or stay in, alone? It matters a lot.

Activity and socializing aren’t just a reflection of age and health — they affect health, too. Ask Arti Hurria, M.D., director of City of Hope’s Cancer and Aging Research Program. She’s studying the factors that contribute to how well older Americans can tolerate cancer-killing chemotherapy.

Among other factors, older men and women who stay socially active — as well as continue their regular activities — tend to go through cancer treatment better.

Of course, a critical part of staying healthy is making sure to get medical checkups and taking medications appropriately. But there other common-sense, daily steps men and women can take, too.

After making sure with your doctor that it’s OK to start an exercise routine, says Hurria, “One important thing to do is just to get out the door and do something. It doesn’t have to be a marathon. It can be regular walks, whether you walk in your neighborhood or on a trail to get out into nature and see something different.”

Nurse Peggy S. Burhenn, M.S., C.N.S., A.O.C.N.S., a professional practice leader in geriatric oncology, stresses the impact of staying connected to friends and family and making new friendships. Seniors with social support think more clearly, stay more independent and have better quality of life.

Some ways of staying connected include volunteering for a charity, going back to work part-time or helping in a community service organization.

“If your network is distant, then writing letters or emails, or getting onto Facebook and talking with friends that way, can help you stay in touch with people,” says Burhenn.

For those already struggling to get around, Hurria and Burhenn suggest turning to their geriatric doctor or nurse for options and ideas on how to get more active. And local senior centers often offer exercise classes customized for men and women with varying abilities. They can be a great place to meet others and learn about outings.

And for all seniors, the National Institute on Aging has a helpful program online called Go4Life that provides ideas, tips and easy-to-follow exercise instructions to encourage strength, balance and flexibility.

“You don’t have to have the energy you did at age 20 to keep active and engaged,” says Hurria. “No one expects a 70-year-old to be like a 20-year-old, or even a 50-year-old. But there is so much that seniors can do to stay healthy, and today is a good time to start.”