The Forerunner 245 Music smartwatch has tools to help keep tabs on your overall well-being and the sleep4 you’re getting at night. These tools provide crucial insight you can use to maximize your training. For example, it’s our first running watch to include a Pulse Ox sensor5. This wrist-based sensor estimates your body’s blood oxygen saturation, which can help gauge how your body is absorbing oxygen — especially while you sleep. And to give you an idea of how you’re sleeping, Forerunner 245 Music tracks your light, deep and REM stages of sleep, along with movement throughout the night. It also features all-day stress monitoring for wellness tracking during the day. If your stress level starts to climb, use the relaxation breathing timer for a few minutes of guided breathing, which can help calm your mind and body. And to help you optimize your body’s energy, Body Battery™ energy monitoring uses collected data to gauge your energy reserves at any moment, so you can plan your day to optimize times for activity and rest.