Although it looks like a walker, the "Rack" all-in-one gym is actually a workout machine, or more precisely, a workout frame. The solid steel frame folds into three different configurations -- flat, standing and bench -- to facilitate a variety of body weight-resistance exercises. The Rack weighs 30 lbs., which is heavy enough to use as a weight for some arm exercises but still light enough to carry around. Its can support body weight up to 300 lbs.
Place the rack in its standing configuration and you can use the uppermost handles to perform full dips, pressing yourself up and down with the force of your arms alone. If you're not ready to do dips with your full body weight yet, lay the rack flat in its bench configuration and do bench dips off the horizontal bars.
In its bench configuration, the Rack doubles as elevated pushup bars for working your chest, triceps and shoulders. Doing push ups on a bar instead of on the floor may reduce wrist discomfort, but the Rack's elevated positioning also makes the exercise a little easier, because you're lifting less of your body weight.
Stand the rack up and you can do modified pullups off the horizontal "dip" bars. Position your body beneath the bars, facing out, and pull yourself up. This is a less-than-ideal exercise, because it works only partial range of motion. Because your feet still rest on the floor, you only lift a portion of your body weight.
Fold the Rack's sides in and lay it flat on the floor. Small wheels mounted on the frame allow you to roll the Rock back and forth. Plant your knees on the floor, grab the rack and roll it forward and back, or kneel on the rack, plant both hands on the floor, and slide your lower body forward and back. Both exercises work your abs.
Lifting the Rack is about the same as lifting two 15-lbs. dumbbells. This is enough resistance to challenge beginning and intermediate exercisers with shoulder presses. Grasp the Rack in both hands and press it straight overhead. Lower the rack until your elbows are roughly level with your shoulders, then press up again.
You can also use the Rack for light curls. Grasp it with your palms up to work your biceps, or use a palms-in hammer-curl grip to primarily work your brachioradialis, a pulling muscle that crosses from your upper arm into your forearm.
Drape the Rack over your back and shoulders as if it were a backpack, placing your arms through the frame to keep it secure. Carrying the Rack provides an extra 30 lbs. of resistance as you perform body weight leg exercises like squats and lunges.