Here is one of those gadgets that you either need to use in a specialized facility or be pretty wealthy to own yourself. The Anti-Gravity treadmill by AlterG allows you to walk, jog or run with an effectively lowered body mass.
Get into the specialized harness, seal it up, and set your target body mass at less than 100%, and get running. The obvious application is rehabilitation for people with lower body injuries, but there are others such as: weight training for older folks, weight loss for heavier individuals so that their weight does not have as much impact on their joints, and of course, aerobic conditioning for athletes and others.
Price: starts at $24,500
(Please note prices are subject to change and the listed price is correct to the best of our knowledge at the time of posting)