Researchers at the University of Wisconsin, Madison compared the heart rate measurements from four brands of wrist-worn activity trackers to an EKG.
At rest, the most accurate device was off by 5 beats per minute.
During exercise, the devices were off from 23 to 41 beats per minute.
Experts say you should know the limits of any fitness device — and if you really need to check your pulse, put your fingers on your neck, or your wrist, and count.
With the weather getting warmer, many people are getting back outside to clean up their yards or garden.
But that may result in sore muscles, back pain or injuries.
Orthopedic doctors say people get hurt when they go from mostly resting to jumping right back into heavy activity with lots of bending and lifting.
They say in the beginning of the season it’s best to start slow. Give your body time to adjust.
Doing a warm-up or stretching can also help prevent problems.
As for today’s tip, here’s how to get enough vitamin D from sunshine without overexposure.
The Vitamin D Council says you only need to expose your skin to about half the time for it takes for it to tan or burn.
People with paler skin may need as little as 10 minutes in the sun.
Darker skin tones will need more sun exposure.
You can also check with your healthcare provider about vitamin D supplements.