EXERCISE FOR PEOPLE OVER 60
With a 5-lb potato sack in each hand, extend your arms straight out from your sides and hold them there as long as you can.
Try to reach a full minute, and then relax.
Each day you'll find that you can hold this position for just a bit longer.
Then try 50-lb potato sacks and then eventually try to get to where you can lift a 100-lb potato sack in each hand and hold your arms straight for more than a full minute. (I'm at this level.)
Thanks to Matt for this exercise program.