3 Exercises to Cure Your Knee Pain :: "Bad knees" aren't sidelining your workout; your hips may be the guilty party. According to a review of 28 years' worth of research on common exercise injuries, hip strength is the biggest predictor of knee pain.
Triple Threat: Three-Machine Cardio Circuit - Instead of spending your whole workout on a single piece of equipment, start machine-hopping around the gym. This triple-threat workout has you on the stationary bike for 15 minutes, then the elliptical, and finally ending on a powerful note with the treadmill. By keeping you on your toes, it leaves little chance of getting bored, but you can expect to build up some serious sweat.