Heart-rate monitors
Vigorous exercise can lead to even more extensive health benefits, and a heart-rate monitor can help you track the intensity of your workout. Most include a chest strap and a wristwatch, but two were wristwatches only, and one was a ring that measures your pulse.
Pedometers
Even moderate activities such as walking briskly can help you stay healthy. Use a pedometer to monitor your activity. The step-and-distance type detects movement to count your strides. Most attach to the user's waistband, though some can be worn in a pocket. The speed-and-distance monitors we tested are worn on the wrist and use GPS monitoring to calculate total speed and distance.
