Flexibility AIS, or 'Active Isolated Stretching' gets results. Developed by Aaron Mattes, AIS is designed to improve the general health of muscles, tendons, and ligaments, beyond improving your flexibility. AIS increases oxegenation and nutrition of myofacial structures, promoting growth and repair while stimulating circulation and lymph drainage. Aaron Mattes’ AIS techniques allow your body to repair itself and also to prepare for your daily activities. AIS techniques involve the method of holding each stretch for only two seconds and is known to work with your body's natural physiological makeup to improve circulation and increase the elasticity of muscle joints and fascia.