Try to open three jars in 10 seconds.
WHAT IT MEANS
The ability to open a jar is a simple test of overall muscle strength. If you don't have the muscle strength to do daily tasks like opening a jar, it could be an indicator you are aging too fast.
WHAT TO DO
Improve your strength. Squeeze a rubberized ball for 90 seconds, three times per day. Improving muscle strength by even just a little bit can add years to your life.