Rest days are important to any workout routine – allowing the body to recuperate. But the antidote to doing too much is not doing nothing, cautions Mark P. Cote, a physical therapist and sports medicine and clinical outcomes research facilitator at the University of Connecticut Health Center in Farmington, Conn. "Doing nothing, regardless of what type of arthritis you have is going to make your arthritis worse," says Cote.

On rest days, he recommends gentle exercises that increase flexibility for arthritis joints. If you usually walk two miles, you might walk just to the corner and back, or try walking in the pool to take advantage of the water's buoyancy.

Try these low-impact exercises to keep joints flexible between workout days.

For the neck:

• Look straight ahead.

• Tilt head gently sideways toward shoulder.

• Hold 3 seconds.

• Repeat to other side.

For the shoulders:

• Stand at the bottom of stairs with your hand on the banister and slide your hand up and down the banister.

• Move to other side of the stairs and repeat with the other arm.

For the arms:

• Hold arms at sides, palms forward and elbows straight.

• Raise arms out to sides and up as if clapping hands above your head.

• Lower arms slowly and repeat.