While you could spend money on a fitness trainer and a fancy gym, this effective workout is absolutely free, it takes just 42 minutes, and you can do it anywhere as long as you have a pair of dumbbells.
Equipment needed: Only one pair of light- to medium-weight dumbbells is necessary (three to 15 pounds), but you may prefer to keep two sets on hand just in case you want to go lighter or heavier, depending on the exercise.
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