Does a Fitbit Improve Your Health?: Studying the Benefits of Fitness Trackers
Since 2009, when the first Fitbit came onto the scene, the rise of the wearable fitness tracker has been swift. Now dozens of companies like Jawbone, Apple, Garmin and Misfit produce complex, ever-more-advanced trackers that tell us how far we walk, how many calories we burn and how long we spent at 90% of our maximum heart rate.
Tracking fitness and quantifying health is not a new thing. Some historians say that the first mechanism to track steps was invented by Leonardo DaVinci in the 1400s. There are letters from Thomas Jefferson detailing his creation of an early pedometer to track steps in the late 1700s. These pre-digital “wearables” didn’t gain much traction in the US until the 1930s, with the popularization of a pedometer: the “Hike-o-Meter.” It was distributed in cereal boxes and was targeted mostly to long-distance walkers. Since then, an interest in recording and analyzing movement data has been on a slow-but-sure rise.
But can wearing a tracker help you meet your health goals? We looked at the science and here’s what we learned about the benefits of fitness trackers:
Fitness trackers improve accountability
Using a tracker to quantify your fitness goals can be more effective when you do it alongside friends. Because it’s tricky to refute hard data, devices that incorporate a social function (like team challenges or sharing your step count publicly) can increase the likelihood of being active, especially if a specific goal has been established. A 2015 study showed that participating in a social sharing system around exercise, including sharing your movement stats for the week, can improve adherence to a fitness program. Users benefited from the emotional support and encouragement received from other participants and people in their community.
If you are motivated by competition, trackers that incorporate that element and share your ongoing progress with friends may also be beneficial.
Fitness trackers can improve your motivation (especially if you’re already active)
Great news if you’re already working out regularly: wearing a fitness tracker can maintain and improve your motivation to workout. Less great news if you’re not active: wearing a fitness tracker will not improve the likelihood of getting more activity in the long run. In one study, trackers encouraged about 16 extra minutes of movement each week, and those 16 minutes are still more likely for someone who is already active.
If you’re already exercising consistently, seeing your daily score on a screen – for exertion, calories burned and steps taken – can motivate you to beat your personal best or to be more active than you were the day before. For folks not regularly working out, they may interpret scores negatively and be less motivated to keep trying. Personal interpretation of results affects how you behave in the future, whether it’s later that same day or next week. In this case, they can function more as facilitator (for existing habits) rather than a motivator (for new habits).
Fitness trackers can improve your target heart rate and maximum exertion
High-intensity workouts that increase heart rate to 80% of your max or greater have been shown to increase metabolic rate during and after workouts, while low-intensity steady-state activity, where your heart rate stays around 65% of your maximum, can increase endurance and promote fat burn. Both are beneficial, since humans tend to overestimate how hard they’re working when asked to self-report without data.
Using a fitness trackers can be a great way to test your endurance and your peak performance levels. Many measure heart rate within 95% accuracy, which can help gauge progress and assist in maximum exertion-focused workouts.
Keep in mind that while many of these heart rate trackers will also claim to tell you how many calories you burned in a workout, many often incorrectly report energy expenditure due to the volume of factors impacting how much we burn.
Fitness trackers don’t necessarily lead to weight loss
Many people begin wearing a tracker to encourage movement for the purpose of finding a healthy body weight. In a study completed in 2014, designed to test if using technology would improve weight loss success, subjects were put on reduced-calorie diets, provided with group counseling and encouraged to increase physical activity. After six months, one group was given trackers to continue to monitor their food intake and activity. The control group was asked to continue to self-monitor their intake and activity.
Turns out: the group that wore trackers lost less weight than the group who did not. There are a few possible reasons for this, including that the tracker can incorrectly report calories burned (leading to increased food consumption) and negative interpretation of one’s progress can be demotivating for some users.
Fitness trackers can have a trickle-down effect
When feedback from wearing a fitness tracker is interpreted positively – “I walked 12000 steps today. I did pretty well!” – behavior changes in other areas of personal wellness can also improve, including getting more sleep, improving eating habits and increasing hydration.
A number of trackers on the market will also measure stress, based on a reading of heart rate variability, which essentially tells you how quickly your body responds to and recovers from pressure-filled situations. Seeing the difference between a stress response and a relaxation response in hard numbers can encourage building a practice to de-stress. Some trackers also include built-in meditation programs.