Jump rope one of the way for cross training.
Tip of the day: JUMP ROPE.
When it comes to cross-training exercises for runners, pool running and elliptical training get the most play. But jumping rope is an excellent activity to add to your training routine – especially if you want to protect against sprains, because it strengthens the muscles and ligaments that support your ankles. Plus, jumping rope is a cardiovascular workout that's easy to do, inexpensive & travels well.