When fitness bands first came out, they did a great job tracking your steps like a pedometer. If you wanted to track your heart rate, however, you had to wear a cumbersome chest strap. (Hint: not comfortable or sexy). Nowadays, many of the best fitness trackers with a heart rate monitor achieve the same feat by using optical technology to monitor the blood rushing through your veins. This information can then be used to estimate how much blood is pumping through your ticker.
Tons of the best fitness trackers now feature these optical sensors, meaning that if you want to know how fast your heart is beating, you no longer have to wrap an elastic band around your torso and spend your whole workout tugging at it so it doesn't ride up.
But how accurate are fitness trackers with optical heart rate monitors? The jury is divided here; However, most fitness experts agree that while the chest straps are more accurate at high-intensity levels (aka when you’re dripping sweat on the final lap of your half marathon), everyday wrist trackers work just fine the rest of the time.
With optical heart rate monitors being so much more comfortable and user-friendly, it often makes the small sacrifice in accuracy worth it. Optical wrist styles appear in virtually every kind of fitness tracker, from basic budget bands to fancy high-end watches. Whatever type of activity recorder you're after, there's a great option for you, below.