Accelerometer-based physical activity: total volume per day and standardized measures.

摘要: The use of accelerometers in physical activity (PA) research has increased exponentially over the past 20 yr. first commercially available accelerometer for assessing PA, Caltrac, was worn on waist and estimated PA energy expenditure kilocalories. Around 1995, emphasis shifted to measuring minutes moderate-to-vigorous (MVPA), especially bouts 10 min or longer. Recent studies, however, show that light-intensity intermittent (nonbout) MVPA also have important health benefits. total volume performed is an variable because it takes frequency, intensity, duration condenses them down into a single metric. appropriate many applications can enhance comparisons between studies. In future, machine learning algorithms will provide improved accuracy type recognition estimation expenditure. However, current landscape objectively measured counts per day (TAC/d) proxy PA. TAC/d percentiles age- gender-specific groups been developed from National Health Nutrition Examination Survey ActiGraph data (2003-2006), providing novel way assess standardized units acceleration could harmonize across should be viewed as additional metric, not intended replace other metrics (e.g., sedentary time, moderate vigorous PA) may related health. As future refinements wearable monitors occur, researchers continue consider reflect addition existing metrics.