The latest Garmin FR235 watch has an optical HR Sensor. The nice thing about this watch is that you can use it with our Group Fitness service since it can rebroadcast the HR signal.
From the DCRainmaker blog post Garmin Forerunner 230 & 235 In-Depth Review:
“Lastly, the FR235 can have its HR signal ‘rebroadcasted’ to other ANT+ capable devices. The unit rebroadcasts the HR over ANT+, identically to that of a heart rate strap. ”
To enable this, you’ll start from the main time page and press down till you see this HR page. Then, you’ll HOLD the up button down for a few seconds, which gives you this little nugget:
