The Forerunner 255S is smaller in size but big on battery life - up to 12 days in smartwatch mode and 26 hours in GPS mode for a complete picture of your health from rest to activity. With the Morning Report you get a quick rundown of your sleep, heart rate variability, and suggested daily workout all in one place as you start your day. Daily suggested workouts for the whole week are available and they adjust after each run to match how your body is performing and recovering. The watch tracks heart rate variability while you sleep for better understanding of your well-being and how your training is going. Get free training plans from Garmin Coach for a 5K, 10K, and half-marathon, or create your own with the Garmin Connect app. Your training status is evaluated to show if you're pushing too hard, and you get extra performance insight and recovery time after your workouts. Multi-band satellite tracking for accurate GPS even in challenging conditions.