Probably most of us are getting too old for this sort of exercise, but we have children and grandchildren who need to keep fit. A good way of doing this is pushups, which have a spinoff in helping heart health:
https://www.livescience.com/64789-pushups-men-heart-health.html?utm_source=ls-newsletter&utm_medium=email&utm_campaign=20190218-ls
“The ability to do a lot of pushups may be a sign not only of strength, but also of good heart health, a new study suggests. The study tested the stamina of middle-aged male firefighters. It found that those who could do more than 40 pushups in a row had a 96 percent lower risk of being diagnosed with heart disease or experiencing other heart problems over a 10-year period, as compared with those men who could do fewer than 10 push ups. However, because the study looked at only male firefighters, who have very active jobs, it's unclear if the findings apply to average Joes.”
I used to be able to do 50 pushups, in my early 50s, but those days have long passed. Today, I would probably either tear my shoulder, or collapse flat on my face, breaking my nose. My wife just read this and said: “That would be an improvement!”