JMIR Publications

ABSTRACT

Background:

Physical inactivity remains the largest risk factor for the development of cardiovascular disease world-wide. Wearable devices have become a popular method of measuring activity-based outcomes and facilitating behavior change to increase cardiorespiratory fitness (CRF) or maximal oxygen consumption (VO2max) and reduce weight. However, it is critical to determine their accuracy to measure these variables.

Objective:

Determine the accuracy of using a smart phone and the application Myworkout GO for a submaximal prediction of the VO2max.

Methods:

162 healthy volunteers, 58 women and 104 men (17-73 years) participated in the study. The study consisted of three experimental tests randomized to three separate days. One day VO2max was assessed by Metamax II, walking or running on the treadmill. The two other days the application Myworkout GO used a standardized high aerobic intensity interval training (HIIT) on the treadmill to predict VO2max.

Results:

There were no significant differences between VO2max directly measured (49 ± 14 mL.kg-1.min-1) compared with the Myworkout GO predicted ( 50 ± 14 mL.kg-1.min-1). The direct and the predicted VO2max values were highly correlated with an R2= 0.97, P<.001 and with a standard error of estimate (SEE) equal to 2.2 mLkg-1min-1, with no sex differences.

Conclusions:

Myworkout GO accurately calculate VO2max with a SEE equal to 4.5% in the total group. The submaximal HIIT session (4x4 minutes) incorporated in the application was well tolerated by the subjects. We now present regular people and healthcare providers a more accurate and practical version of health risk estimation. This might increase physical activity and improve exercise habits in the population.