Have you tried TRX yet? The best thing about this type of training is the unavoidable balance training that comes along with each movement. Since the cable itself is unstable, you must be the one to stabilize your body. That way, even if you’re doing a TRX row that focuses on your back and biceps, you are also using your core, shoulders and more to keep your body stable.
The TRX strap is such a versatile piece of equipment you can even do your entire workout with it. You can get a total-body workout and avoid the crowds. Here’s what I did the other night, entirely on the TRX: Close Grip Rows + Reverse Flys + Push Ups (If you find it hard to balance on the TRX, just do them on the floor.) + Bicep Curls + Triceps Presses + Reverse Lunges + One Leg Squats + Suspended Crunches.