It outperformed the Polar M430 and the Garmin Forerunner 235. We had no problem getting two weeks out of the Forerunner 35 in normal usage mode (i.e., running 2 or 3 times a week for about an hour and using the watch daily with smart notifications) and over 12 hours in activity mode! My battery does not stay charged for very long. Decrease the screen brightness ( Display Settings). Shorten the display timeout ( Display Settings). Decrease the volume ( Adjusting the Volume). Turn off the wi-fi radio when it is not in use ( Wireless Network Settings). Put the device in power saving mode when not in use ( Turning the Device On On this day, we got 10.5 hours of GPS life, which is less than the Garmin claim. And with daily activities averaging 3-4 per week (at least one hour in length), the Forerunner 45S lasted closer to 6 days than the claimed 7. There are some devices at the same price point that boast much longer battery life if that's what you care about most. Garmin Forerunner® 255S, Smaller GPS Running Smartwatch, Advanced Insights, Long-Lasting Battery, Powder Gray , 41 MM $349 Garmin Forerunner 255s / 255s Music GPS Running Smartwatch - 41 mm Garmin Battery Life Expectancy. If maintained correctly, your Garmin device can last several years. However, the battery life of any device reduces over time, and Garmin devices are not exempt. For example, a Garmin Forerunner 235 battery lasts up to 11 hours with GPS tracking and 9 days in SmartWatch mode. How long does the Garmin warranty last, and what does it cover? Consumable parts, like batteries (unless the battery problem is due to a defect or bad workmanship). Garmin quotes the Forerunner 245 Music’s battery to last up to seven days in smartwatch mode or between 6-24 hours in GPS mode depending on whether or not you’re playing music. I’ve found The third major contributor to your sleep score is a personal recovery metric. This element is derived from the same science that powers the all-day stress tracking and Body Battery™ features on your Garmin watch. This means changes in how your heart beats from one moment to the next are analyzed to reveal stress and recovery states occurring RujjbFz.