TheraBand Professional Latex Resistance Bands are available in 8 color-coded levels of Progressive Resistance color-coded progressive resistance gives at-a-glance documentation of progress from one level to the next and allows the user to progress as they get stronger versatile and convenient It is used for stretching toning and conditioning all major muscle groups increases both strength and flexibility subtly and naturally without weights It can be performed anywhere it is ideal for conditioning and rehabbing muscles as well as specific training for yoga cross fit lower body Pilates rotator cuff strengthening and running as it happens as you grow stronger you can move up to the next color making these bands ideal for strength training and physical therapy programs. It is recognized by professionals in clinics and hospitals as the original system of progressive resistance the best resistance bands for stretching strengthening and rehabilitation.