Take the electrical signal straight from the muscle and put it into your device. Thanks to shrinking amplifier technology, we can now do exactly that!
Measuring muscle activity by detecting its electric potential, referred to as electromyography (EMG), has traditionally been used for medical research. However, with the advent of ever shrinking yet more powerful microcontrollers and integrated circuits, EMG circuits and sensors have found their way into all kinds of control systems.
This sensor will measure the filtered and rectified electrical activity of a muscle; outputting 0-Vs Volts depending the amount of activity in the selected muscle, where Vs signifies the voltage of the power source. It?s that easy: stick on a few electrodes, read the voltage out and flex some muscles!
This kit comes with everything you need to start sensing muscle activity with your Arduino or controller of choice.

Features:

• Small Form Factor
• Specially Designed For Microcontrollers
• Adjustable Gain
• 3.5mm Connector
• Breadboard Compatible
• Power supply voltage: min. +-3.5V

Includes:
1 x Muscle sensor board
1 x Professional EMG cable
3 x disposable surface electrodes