If you're looking to add a great cardiovascular exercise to your fitness routine, then ski steps is a solid option. The movement in ski steps simulates cross-country skiing. However, the exercise can be done almost anywhere, and you don't need any ski equipment. And it's not necessary to be anywhere near snow — unless you just want to be.
Stand upright, hands at sides, feet shoulder-width apart.
Jump your right foot forward a step and your left foot back a step (go as far as you feel comfortable) and simultaneously swing your left arm forward and your right arm back behind you.
Reverse the action by jumping your left foot forward and right foot back while simultaneously swinging your right arm forward and left arm back.
Repeat the motions continuously, in alternation, for a set amount of time or number of repetitions.