This small-size replacement elastic strap for your Garmin heart rate monitor is ideal for runners and riders with a smaller frame. Training with a wireless heart rate monitor helps you get more from your workout with a Garmin Edge bike computer or Forerunner sportswatch. The digital monitor continuously tracks heart beats per minute to help you improve your fitness level or compare your pace and heart rate to previous workouts. Garmin’s ANT+ technology seamlessly pairs the heart rate monitor to your sportswatch avoiding crosstalk with other equipment or other people’s monitors. Training with heart rate is a vital indicator for whether you’re working your body too hard or not hard enough. Relying on pace or speed data won’t give you the same accuracy – your heart rate is a better indicator of how hard your body is working. Your exertion level can vary depending on factors such as level of fitness, environmental elements like weather and temperature and your general wellbeing. Stress, fatigue and sickness can elevate your heart rate so a workout on these days may still feel difficult even if you reduce the speed or distance. Train in your optimal zone for current, average, highest, lowest, max and 5x zones. Once you’ve determined your max, key it into your Garmin Forerunner or Edge and it will calculate your zones and handle the workout for you.