Reason A: You've never seen anyone at the gym actually use one, so you figure they must not be very effective.
The truth: Climbing machines are mega calorie burners -- moving at a swift rate of 1.5 mph burns an average of 16.2 calories per minute, cites one machine's manual. (For comparison, running at 7.5 mph burns about 14 calories per minute). "That thing will wear you out fast -- it's one of the most intense cardio pieces of equipment there is," says Erin Oprea, certified trainer and owner of Oprea Personal Fitness in Nashville, Tennessee. It's a total-body workout, utilizing your arms, legs and core, and the resistance means you'll get toning benefits in addition to cardio gains. Plus, the climbing motion is gentle on joints, so the risk of injury is minimal, and people with bad knees, ankles or hips should have no problems with it. The one exception: People with shoulder injuries, says Oprea, who may find that the motion aggravates the joint/problem.
Reason B: You think it requires someone more coordinated (or fitter) than you to stay on the thing.
The truth: The machines are definitely challenging, but adjusting the length of your "stride" (or how high you reach your arms and how low the foot pedals go) and opening or narrowing your stance on the pedals allows you to increase or decrease the intensity. Jason Walsh, a personal trainer and the founder of Rise Nation, a Los Angeles fitness studio offering climbing machine group classes (celebrities like Hilary Duff and Minka Kelly are fans), recommends asking a trainer on duty to show you the ropes. Also, rather than attempt to sweat it our for your normal 30-to-45-minute cardio session (as you might do on other pieces of equipment), try shorter bursts of about 10 minutes or hopping on for 1-minute intervals during a circuit workout.
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