Those of you who regularly follow my blog, know that I often post images of my daily calorie burn rates as tracked by the activity app of my Apple Watch. But, what you may not know is that I actually have a love-hate relationship with activity trackers and monitors.

While these devices can serve as great motivational tools, overestimating your daily calorie expenditures by way of activity trackers and monitors might actually hinder your continued progress.

So, before you get overly excited about how many calories you burn each day, consider these facts.

Your daily calorie expenditure is highly contingent on your metabolic rate. Whether you use an activity tracking device or those generic calorie counters on exercise machines, you initially have to plug in specific information about your age, height and weight, which is used to estimate your metabolic rate.

Your daily calorie expenditure is highly contingent upon the metabolic rate.

The metabolic rate (or metabolism) is the amount of calories your body uses to fuel all vital functions including breathing, blood pressure and brain activity. The higher your metabolism, the more calories you’ll burn on a day-to-day basis.

Related Article: The Important Role of Metabolism in Weight Loss

In addition to your age and physical characteristics, your daily levels of physical activity largely affect your metabolic rate. In fact, if you’re regularly physically active, your metabolic rate will naturally adapt to a higher level allowing you to burn more calories, which is indeed a plus.

However, the downside here is that the more you engage in any given type of activity, the fewer calories your body actually burns performing it.

Due to the adaptive nature of the metabolic rate, no single activity tracking device or calorie counter is 100% accurate when it comes to measuring calories.

Your metabolic rate naturally becomes sluggish and may decrease if your physical activity patterns or general exercise routine doesn’t change. As such, if you’ve been counting 500-600 calories burned with an hour of treadmill jogging or elliptical training for the past three months this is likely an overestimate due to your body’s general familiarization with this activity.

This is a point that’s extremely important to understand, especially if your fitness goals are centered on weight loss.

Due to the adaptive nature of the metabolic rate, no single activity tracking device or calorie counter is 100% accurate when it comes to measuring calories.

Related Article: Why You Need to Change Your Exercise Routine Regularly

There are 3,500 calories in one pound of fat; therefore, if you want to lose weight, you must create a 3,500-calorie deficit by either burning 500 calories per day or restricting 500 calories per day by eating less.

But, solely depending on an estimate of 500-600 calories burned during exercise, as described above, may hinder weight loss and, in some instances, even lead to weight gain, particularly if you’re consuming too many calories.

I’ve seen this time and time again with clients who tout calorie expenditures in excess of 1,000 per day from the same ole routine without so much as a pound of fat lost.

Facts like these prompted me to write my book Leaving Your Fat Behind. My goal with this book, and in everything I do, is to teach people the tricks of the trade when it comes to successfully losing weight and maintaining that loss over time.

Interestingly enough, by adding a little variety to your exercise program your body will remain physically challenged and thereby burn more calories.

Even the perfect exercise routine can become stale after a while. If you’ve been treading on the elliptical trainer for three or more months it’s time to switch it up, as you’re not burning the calories you think you’re burning. In addition to switching up your routine, it’s important to use the calorie outputs depicted on activity tracking devices and calorie counters as estimates not absolutes.

A good rule of thumb is to underestimate the amount of calories you burn and make an effort to move more and more throughout the day.

By adding a little variety to your exercise program your body will remain physically challenged and thereby burn more calories.

For weight loss, it’s also a good practice to overestimate the amount of calories you consume to ensure that you’re not eating too much.

Personally, I use activity trackers to gauge the overall intensity of my workouts. In addition, I especially love their motivational features, which essentially encourage me to get up and move whenever I’m inactive. When it’s all said and done, despite obvious inaccuracies in estimating daily calorie expenditure, activity tracking devices remain to be excellent tools for motivating people to move more.

It’s just best not to rely on them as sole indicators of your daily calorie burn rates.