TRX Fitness Strap
Credit: Photograph by Michael Pirrocco

The TRX is not only the most compact and economical home gym money can buy but also introduces all-important instability to almost any basic exercise, like a push-up or a row. "For those exercises alone, it's worth the price," says Boyle. "It gets the whole body working as a unit and is fully adjustable, so you can make it hard or easy. Plus, the rotating handles are shoulder-friendly."

Try: TRX Push-Up
With both feet suspended in the loops, an arm's length above the ground so your body is parallel to the floor, perform a push-up as described previously. (Or try rows, as described before.)