Garmin Forerunner 235 GPS Running Watch: Make the most of your workout with this watch, which uses a wrist-based Elevate heart rate monitor to calculate your VO2 max and help you predict race times for various distances. Track your activity levels and receive a nudge when you have been sitting for too long, and monitor your steps taken, calories burned, distance traveled and sleep quality and quantity for an overall picture of your physical fitness.
I love this watch! The best part is not having to wear a chest strap to track my heart rate. I run 3+ times a week and cross train 3 times a week and use my watch to track all of my workouts. You can set it up for interval training and it also has settings for running indoors, biking outdoors and indoors. I use the other setting for cross training. It's very comfortable. I thought it would seem big at first but I have no problem wearing it. It's very light. The gps syncs up really fast and as long as it is tracking your heart rate before you start your workout it is pretty accurate. If you start your workout without your heart rate recognized, it normally won't pick it up. The only issue I've had is that occasionally when I interval train it doesn't track my heart rate accurately. Sometimes it does, sometimes it doesn't. I don't know if I'm moving too much but I'll be totally out of breath and it says my heart rate is 80 or 90 bpm. It will eventually find it, but for a while I know it isn't right.