At one point or another I've signed up for various email newsletters which mostly get trashed without reading but today I got one that was somewhat interesting so I'm actually posting the tip...
Lie facedown, arms and legs outstretched a few inches above floor, head in line with spine.
Raise left arm and right leg off floor. Lower and repeat with right arm/left leg. Return to start and repeat the series.
Don't lower arms or legs completely until the end of the set. Don't hold your breath.
Muscles Worked: Lower back
Time Involved: 1-2 minutes
Body Benefit: Increase strength and endurance in your lower back, preventing aches and pains.
You should always check with your healthcare provider before doing any exercise program.