PEN AND INK WORLD The Longest Mission

Deep in space...
A Heart Shield provides protection from Gamma Rays and other dangers.
The crew arrived safely at their destination. The Captain said, "Geez, what a trip, 20,000 miles and stuck in our seats most of the time...I thought we'd never get here! Hey, while the space station is filling up the ship, why don't we go stretch our legs."
Uh-oh, I've got a cramp