Put stretching at the top of your fitness to-do list.
A good rule of thumb: If you’re under the age of 40, hold your stretches for 30 seconds; if you’re over 40, hold them for 60 seconds.
As you age, your muscles become less flexible, so upping your stretching time will help keep them strong and limber.
Want to really maximize your muscles?
Stretch several times during the day (once an hour, if you can) to keep your body loose and your muscles feeling and looking good.