If your Garmin Vivoactive 4s is not starting, it could be due to a variety of reasons. Some common causes could be a drained battery, a software issue that requires a reset, or physical damage to the device. Try charging the device for a few hours, performing a soft reset by holding the power button for 15 seconds, or contacting Garmin customer support for further assistance. **

The Garmin Vivoactive 3 may not be connecting for a few reasons. First, ensure that the device is fully charged and powered on. If the device is on, try restarting it to see if that resolves the issue. Additionally, check that the Bluetooth on your smartphone is turned on and that the Garmin Connect app is up to date. If the problem persists, try forgetting the device on your smartphone and then re-pairing it. If none of these solutions work, there may be a hardware issue with the device and it may need to be repaired or replaced. **

Intensity minutes on the Garmin Vivoactive HR are measured based on the intensity of your physical activity. The device uses heart rate data to determine the level of intensity during your workouts. It tracks the time spent in different heart rate zones, such as moderate or vigorous, and accumulates intensity minutes accordingly. This feature helps users monitor their activity levels and ensure they are meeting recommended guidelines for physical activity. **

To do interval training with the Garmin Vivoactive, you can use the built-in interval training feature on the device. First, you'll need to create a custom workout on the Garmin Connect app or website, specifying the intervals, rest periods, and number of repetitions. Once the workout is created, you can sync it to your Vivoactive and start the interval training session from the device. During the workout, the Vivoactive will guide you through the intervals with alerts and notifications, making it easy to track and complete your interval training session. **

The VO2max of the Garmin Vivoactive 3 may decrease due to a variety of factors such as changes in fitness level, decreased physical activity, or changes in overall health. VO2max is a measure of the maximum amount of oxygen a person can utilize during intense exercise and is influenced by factors such as age, gender, and genetics. If a person's fitness level decreases or if they become less active, their VO2max may also decrease. Additionally, certain health conditions or medications can also impact VO2max. **

The intensity minutes on the Garmin Vivoactive HR are measured based on the user's heart rate data. The device tracks the time spent in different heart rate zones, such as moderate and vigorous, and accumulates these minutes to calculate the total intensity minutes. This feature helps users monitor and reach their recommended weekly goal of 150 minutes of moderate-intensity exercise or 75 minutes of vigorous-intensity exercise. The Garmin Vivoactive HR uses this data to provide users with insights into their overall activity level and helps them stay on track with their fitness goals. **

If the performance of your Garmin Vivoactive 3 has not improved despite changing the battery, there may be other underlying issues causing the problem. It could be related to software glitches, hardware malfunctions, or even a need for a software update. It is recommended to contact Garmin customer support for further assistance in troubleshooting the device and resolving the performance issues. **

The Garmin Fenix 5 does not burn calories itself, as it is a fitness tracker that monitors your activity and provides you with information on the calories you burn throughout the day. The number of calories burned will vary depending on factors such as your age, weight, height, activity level, and the intensity of your workouts. The Garmin Fenix 5 uses sensors to track your heart rate, steps taken, and other metrics to provide you with an estimate of the calories you have burned. **