Heart Pulse Sensor Amped

The Pulse Sensor Amped is a plug-and-play heart-rate sensor for Arduino. It combines a simple optical heart rate sensor with amplification and noise cancellation circuitry. Simply clip the Pulse Sensor to your earlobe or finger tip and plug it into your 3 or 5 Volt Arduino and you’re ready to read heart rate.

More information is available on the website of Sparkfun.