Bosu ball Bosu (which stands for “both sides up”) balls integrate balance with other forms of exercise. Use as a step for a cardio workout; put the platform side up for push-ups; ball side up for squats.
Exercise ball This workout tool travels well. Just pack a deflated ball and a small lightweight pump. You can use an exercise ball to do modified push-ups—by having your legs on the ball rather than on the floor, you’re forced to use more stabilizing muscles than traditional push-ups. Or do ab exercises. For example, lay on the ball so it is in the lower part of your back. Put your hands up to temples with elbows out to sides and tongue lifted to the roof of your mouth (this engages the intrinsic neck stabilizers that support the neck during the exercise). Crunch upward for three sets of 15, making sure to utilize abs in the downward movement as much as in the upward motion.
Exercise band This ultra-portable elastic band can be used for many workouts. Try bicep curls: Stand on one end of the band while grasping the other end in one hand. Start with elbow bent at a 90-degree angle and pull hand up to shoulder. Slowly release. Or do hamstring stretches: Sit on the floor with legs extended in front of the body and put band around feet while holding one end in each hand. While maintaining straight legs, slowly pull the band to bring the toes toward your body. Hold for 15 to 30 seconds.
Jump rope Once you get the hang of it, use a jump rope for ten-minute interval cardio sessions: Do 30 seconds to one minute hard followed by one to two minutes of slower jumping. Continue for ten minutes.
Water weights Want to do your free-weight gym routine at home, work, or on the road? These plastic weights are light and compact, but when you fill them with water they can weigh from 2 to 10 pounds.
Yoga mat Keeping up with your stretching, crunches, and push-ups on the road isn’t nearly so difficult when you don’t have to get down on a dirty floor. Thin, light, and packable travel mats are available at www.matsmatsmats.com.

—D.M.