How is jumping rope to build fitness? Can you recommend a regimen?

Jumping rope is a great cardiovascular exercise. It's one of the foundations of a boxer's conditioning program, and you've got to be in shape to box. The tennis champ Jimmy Connors used to skip rope as part of his conditioning routine.

Wear supportive cross-trainers, tennis or basketball shoes while skipping rope. Running shoes won't give you enough forefoot support and are not intended for bouncing on the balls of your feet. Avoid jumping on concrete, floors laid over concrete, and other hard surfaces like tile. If you don't have a springy wooden or carpeted floor, place a thin exercise mat on whatever surface you do have and jump on that.

Jumping rope is strenuous and may be hard to sustain for the 30 minutes that you need for a good aerobic workout. Try this routine, used in boxing classes:

• Skip rope for three minutes. (A round in boxing is three minutes long.)
• Take a minute off, and do as many crunches as you can.
• Skip rope for another three minutes.
• During the next minute between rounds, do as many push-ups as you can.
• Back to skipping for three minutes
• Do crunches for another minute. Repeat.

You can alternate rounds of skipping with crunches and push-ups until you've completed 30 minutes or more of exercise. After the second or third round of skipping, your heart rate wonít drop that much during the crunches and push-ups.

You might not be able to do more than a few intervals of push-ups. Use any exercise you want during the minute between rounds. Try doing squats and lunges (with or without weights) to give your larger leg muscles added work. Do upper-body exercises with dumbbells during that minute. (Use proper form. Don't rush.) One more thing: Skipping rope emphasizes your calves, so be diligent about stretching them.

Another advantage of skipping rope is that you can take one anywhere. If you're traveling and the place you're staying doesn't have a gym, you can bring your own.

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