This sport watch gives you several functions to keep track of different key metrics during the workout. Use the built-in heart rate monitor to keep track of your training progress.
From Amazon
Garmin Forerunner 255 Easy to Use Lightweight GPS Running Smartwatch, Music Storage, Advanced Training and Recovery Insights, Safety and Tracking Features, Up to 14 days Battery Life, Black
RunningXpert
Garmin Forerunner® 255 Music White ONESIZE
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