Jumping rope is a great way to maintain fitness on board a ship or in confined spaces. It can provide a high intensity, cardio respiratory workout if done long enough and fast enough. If the pace is fast, it is equivalent to running in terms of energy expenditure.  Jumping rope does not have to be boring, especially if you use different types of jumps. See examples below the names and an explanation for alternatives to the basic jump.

Type of Jump & Description
 
BOXER’s DANCE - With both feet together, shift weight from right to left with each jump.
RUN – Jump to the left while lifting left knew, then switch.
SHUFFLE – Start with right foot forward and left foot back, then switch each jump landing on both feet at same time.
KNEE-Toe – Tap right toe on the floor, then jump from your left foot to your right; at the same time lifting left knee as high as possible. Switch legs.
DOUBLE ROTATION – Twirl the rope around twice between each jump.
JUMPING JACK – Jump two times with feet together, then do a jumping jack every third time.

In terms of gear, many different types of rope are available, and rope jumping can be limited by the quality of the rope. Most experts recommend lightweight leather ropes. Believe it or not, many books have been written about jumping rope is a great activity, especially if you are in a confined environment.

Article Ref:
The Navy SEAL Physical Fitness Guide