The Spring Resistance Knee Strengthening Sleeve

Only available from Hammacher Schlemmer, this is the wearable knee exerciser that strengthens the knee using patented resistance springs that increase muscle activity by 40% while walking and 200% while running. Developed in collaboration with biomedical researchers and tested on British professional athletes, the knee exerciser builds and bolsters muscle around the knee through resistance tension bands and kinetic compression. It is versatile for routine activities like walking and jogging or for more strenuous activities, such as cycling, skiing, and tennis. Advanced technology lets the sleeve breathe and respond to high and low temperatures for wearing comfort. Comes fitted with the lowest level of resistance and a set of yellow and black bands for additional resistance to suit your needs. Resistance (white bands, 7 3/4 lbs.); (yellow bands, 11 lbs.); (black bands, 16 1/2 lbs.). One sleeve fits either knee.