Activity monitoring devices provide reliable records of activity

Whilst Fitbit-Flex is one of the most popular wearable devices currently available to measure physical activity, very little research has been conducted on its accuracy. The use of such devices also offers significant promise to researchers and clinicians working in cardiac rehabilitation program to evaluate, monitor and encourage physical activity that is integral to recovery. As the researchers from the Charles Perkins Centre at the University of Sydney explain:

"Accurate activity tracking devices offer researchers and clinicians the potential to influence physical activity behavior change, make a direct and real-time impact on self-management of physical activity and offer clinicians real world assessments of their patients' daily activity patterns."

In order to ascertain the reliability of Fitbit devices and evaluate their effectiveness for monitoring the physical activity of cardiac patients, the researchers evaluated 48 patients and family members participating in community-based exercise programmes. The 48 participants wore the device over four days to monitor daily step counts and minutes of moderate to vigorous physical activity (MVPA). The researchers discovered that:

"Fitbit-Flex is a valid and reliable device for activity monitoring specific to predicted attainment of physical activity guideline recommendations (i.e. step counts and minutes of MVPA). It is also useful for monitoring physical activity in cardiac patients and for comparison among individuals. However, caution must be taken when using Fitbit-Flex for research purposes as it slightly over-estimates step counts and MVPA. Nonetheless, Fitbit-Flex is capable of continuously monitoring free-living conditions and for providing valuable physical activity data for clinicians, individuals and researchers to track physical activity levels."