Quiz: How Healthy Is Your Resting Heart Rate?

Bradycardia, or a heart rate below 60 bpm (in nonathletes), can be caused by conditions like sleep apnea, an underactive thyroid, heart inflammation or congenital heart defects.

Your maximum heart rate is estimated by subtracting your age from 220. This number helps determine target heart rate zones for moderate-intensity (50 to 70 percent) and vigorous-intensity (70 to 85 percent) exercise.

While some studies have found certain trackers (like the Apple Watch or Fitbit) to be more than 90 percent accurate, others — especially in people with A-fib — showed that readings could be inaccurate. Trackers are useful for spotting trends, but they shouldn’t replace clinical tools like EKGs.

Drinking enough water helps maintain proper blood volume and circulation. When you’re dehydrated, your blood thickens and your heart has to work harder, which can raise your resting heart rate. Other recommended habits include reducing caffeine and alcohol intake, quitting smoking and managing stress.