Activity tracking devices may not improve health, help reduce weight

Activity trackers seem like the god-sent device for people trying to lose a few pounds or get back into shape, but without additional incentives, do these devices actually provide positive results?

Fitbits, Jawbones and other activity trackers have become ubiquitous due to claims that tracking your steps and diet will help their wearers become healthier. The strange thing is, even though these devices promise results, little tangible evidence exists showing that they actually improve health. In a study published in The Lancet, researchers, led by Eric Finkelstein, PhD, looked to see if using fitness trackers, by themselves or along with cash incentives or charitable donations, can increase physical activity and improve the health.

The study enrolled 800 participants ages 21 to 65, assigning them to three groups: the control group received no tracker or incentive, a second group received a Fitbit Zip and a third received the tracker and either cash or charity incentives. The incentives were dependent on the number of step achieved weekly and moderate-to-vigorous physical activity (MVPA) sessions per week, both of which recorded from a sealed accelerometer. These measures were recorded six months after the start of the study and then again after 12 months. The study also included measures for total steps, participants reaching 70,000 steps a week, weight loss, blood pressure and quality of life.

The results were split into the findings at six and 12 months.

Six months

• Compared to the control group, the cash incentive group logged an additional 29 MVPA bout min per week.
• The charity incentive group logged an additional 21 MVPA bout min per week.
• The results between the Fitbit-only and control group were not significant.
• Average MVPA bout min per week in both incentive groups was not significantly greater than the Fitbit-only group.

12 months

• The Fitbit-only group logged an additional 37 MVPA bout min per week.
• The charity group logged 32 MVPA bout min per week more than the control group.
• The difference in MVPA between the cash and charity control groups was not significant.
• Physical activity fell by 23 MVPA bout min per week when comparing the cash incentive group to the Fitbit-only group.

Overall, there was no overall improvements of weight, blood pressure or quality of life in any groups. While the cash incentive group showed the most promise in increasing physical activity at six months, this rate was not maintained afterward. After the 12-month period the activity trackers, even when paired to incentives, were effective in maintaining the rate of exercise performed, but they failed to improve any of the health outcomes measured.

“Although other incentive strategies might generate greater increases in step activity and improvements in health outcomes, incentives would probably need to be in place long-term to avoid any potential decrease in physical activity resulting from discontinuation,” wrote Finkelstein et al.