Fitness trackers are a great place to start when it comes to maintaining a healthy lifestyle. Most of these devices present us with a healthy dose of fitness information and insights.

However, all of these metrics may not be equally important. And with so many data points available, it can be difficult to know which ones will actually help you improve your wellness. These are the key health data points you should be monitoring to help you get the most out of your fitness tracker.

1. Heart Rate

Your heart rate (HR), or pulse, is a vital metric that indicates the number of times your heart beats per minute (BPM). A good fitness tracker should warn you if your heart rate has gone above or below a certain threshold.

For adults, a resting heart rate (RHR) of 60–100 beats per minute is usually considered normal, according to the American Heart Association (AHA). The AHA advises that it's also important not to go over the recommended maximum heart rate, as this could lead to unnecessary exertion and cause heart conditions down the line.

Resting heart rate on fitness tracker

You should monitor your pulse actively during high-intensity training or workouts—it tells you whether you should push yourself harder, or slow down. This can help you manage your workout routines and energy levels better.

Most fitness trackers that monitor your heart rate come with proper tracking capabilities with built-in accelerometers or optical sensors, or use a technology known as PPG (Photoplethysmography)—but they can work effectively only if you've set up an appropriate profile for yourself first.

2. Sleep Quality

Sleep quality depends on a variety of factors and can be further influenced by depression, insomnia, or other conditions. This metric is critical for people who want to improve overall sleep patterns and for those who wish to track the quality of their sleep based on individual factors such as snoring, light patterns, and heart rate.

With advanced sleep quality and snore detection capabilities offered by Apple, Samsung, and Fitbit devices, you can keep track of the overall duration of sleep as well as time actually spent in REM sleep. When used over longer periods of time, this metric can provide more accurate insights.

3. Body Composition

Body composition isn't just about your weight; it's an important metric that helps you determine fat percentage relative to lean muscle or body mass.

Smartwatches such as the Samsung Galaxy Watch 4 can measure this with bio-impedance technology (BIA). This sends a small electric current through your body and measures the resistance that it encounters. It's particularly important if you're trying to lose weight or trying to build muscle.

Tracking body composition in your fitness tracker

The American Council on Exercise (ACE) recommends essential fat levels between 2–5 percent for men and 10–13 percent for women. While too much body fat can be a risk factor for heart disease, diabetes, and other health problems, too little can also be an issue. Further, this may also indicate a lack of protein in your diet which makes it harder for your body to repair and rebuild itself after exercise.

4. Active Minutes

This is a somewhat vague metric that takes into account just about any physical activity during the day. However, it's still useful because it lets you understand the level of physical activity you're involved in compared to time spent sitting around with no exercise.

Tracking active minutes on fitness tracker

If you aren't getting enough activity, your body may start to feel sluggish and out-of-sorts. You can use your fitness tracker to help you keep track of the moderate-intensity activity (like walking) or vigorous activity (like running) you get each day.

The more active you are, the better. In fact, the Center for Disease Control and Prevention (CDC) recommends 150 minutes of moderate-intensity activity for adults each week. That's about 21 minutes per day, or 30 minutes if you only exercise on weekdays.

5. Menstrual Health

Tracking your menstrual cycle can be useful for managing your reproductive health. Devices such as Fitbit wearables help you log symptoms and enter relevant information that can help you monitor your cycles and other symptoms. Other fitness trackers might be able to sync with period tracking apps for this purpose.

You may want to do so for a number of reasons—for instance, irregular cycles can be an indication of stress or other health conditions in the long run.

6. Cadence (for Runners)

If you're an athlete or sports enthusiast, you might want to closely monitor more specific metrics that are important to your sport, such as cadence, VO2 max, and calories burned. As you run, your cadence refers to the number of steps you take per minute. A higher cadence means taking shorter strides and using less energy.

Tracking cadence and running metrics on a smartwatch

Cadence is important for runners and athletes who're looking to improve their technique, footwork, and efficiency. Understanding this can help them burn more calories and improve cardiovascular health. A study in Medicine and Science in Sports and Exercise found that increasing cadence helps reduce impacts on lower body joints.

7. VO2 Max (for Endurance Training)

VO2 max is a measure of cardio-respiratory fitness, and it's one of the best metrics for monitoring overall health, endurance, and aerobic capacity. The VO2 max test involves measuring the amount of oxygen you consume during a given time. Also known as maximal oxygen uptake, VO2 max can be interpreted differently for people of varying age groups and is influenced by gender and fitness levels, according to an article by Garmin.

A good score means that you'll be able to work harder for longer periods, which is helpful when running longer distances or cycling in difficult terrain. The VO2 Max feature is available on select Apple or Garmin devices (and a few others)—such as the Apple Watch Series 7 GPS Smartwatch or the Garmin Fenix 5 Multisport GPS Smartwatch.

Essentially, this will give you an idea of how hard your body is working at different levels of activity so that you can adjust your fitness goals and customize your workouts using websites or other tools accordingly. If you're trying to build endurance or strength, this is a great way to measure progress.

8. Calories Burned for Overall Fitness

Person monitoring fitness metrics

Fitbit wearables offer a calorie burn counter that will give you a good starting point, and other devices have similar features. Accuracy may vary slightly across devices—more so when tracking workouts like cycling and swimming, where the number of calories you burn depends on technique, intensity, and duration too.

However, you can easily calculate your basal metabolic rate (BMR) with calorie-burn estimates. This can help you make more informed decisions about your food intake and exercise habits.

Keep an Eye On Your Health Data

When it comes to your fitness tracker, there's no shortage of health insights. Use this guide to focus on the key metrics that will have the biggest effects on your wellness. Once you're in the habit of monitoring your fitness information regularly, you'll have a much better idea of where you stand. Then, you can start to dive into more specific health data points and fitness routines.