If your body drops it, you just gotta get it back.
As you get older, your body tends to lose its muscle mass much more quickly, and it becomes more difficult to build it back up. This isn’t a disease or anything, it’s just a fact of getting older, and the reason a lot of older folks tend to be on the skinnier side. Reduced muscle mass can make you much more frail and easy to injure, as well as more easily winded. According to researchers, age-related muscle loss can begin as early as 30 years old, so before you shrivel up, start making up the difference with tweaks to your exercise routine.
Obviously, I’m not telling you to start bench pressing giant weights from age 30 to 80 (unless you’re into that, I guess). Rather, you can keep doing the stuff you already do, just with a few sprinklings of extra impact on top. For example, try adding a couple of seconds to every exercise rep you perform. Just being forced to hold your posture for a little bit longer multiplies your gains in the long term, as well as builds additional resistance in your limbs.
Of course, it’s not just about your limbs. You should also begin incorporating workout moves that work your entire body, including your back, neck, shoulders, thighs, or whatever else you can get at, and preferably all at the same time. You should also incorporate regular strength training into your week if you don’t already, two times a week minimum. Just a few minutes of dumbbells is fine to keep your body strong and robust.
I won’t sugarcoat it for you: this will become progressively more difficult as you get older. But as long as you stick with it, it will get easier, even into your elderly years.