Through biofeedback, you can learn to achieve certain behaviors like physical relaxation, tension or relaxation of certain muscles, or even a reduction of negative stress controlled and at will. This happens by influencing your breathing, muscle tension, heartbeat, blood flow, and perspiratory glands - all parts of your body that reflect the current state of certain parts of your nervous system. To measure this, adhesive electrodes that attach fast and comfortably to the skin are used. Sensors measuring tissue blood flow and temperature are attached by velcro fasteners. The sensors and electrodes are small, lightweight, and do not impair the wearer during exercises.