For total EE , correlation coefficients were statistically significantly lower in uniaxial compared to multisensor devices .
For active EE , correlations were slightly but not significantly lower in uniaxial compared to triaxial and multisensor devices .
The high level of heterogeneity in the validation studies is only partly explained by the type of activity monitor and the activity monitor outcome .
Triaxial and multisensor devices tend to be more valid monitors .
The assessment of physical activity in healthy population s and in those with chronic diseases is challenging .
The aim of this systematic review was to identify whether available activity monitors ( AM ) have been appropriately vali date d for use in assessing physical activity in these groups .
Daily physical activity assessment: comparison between movement registration and doubly labeled water.
The use of movement registration for daily physical activity assessment was evaluated during a 7-day period in 30 free-living subjects . Body movement was registered with a Tracmor motion sensor consisting of a triaxial accelerometer and a data unit for on-line processing of accelerometer output over 1-min intervals . Average Tracmor output was correlated against four different energy estimates : 1 ) average daily metabolic rate ( ADMR ) , determined with doubly labeled water ; 2 ) ADMR-sleeping metabolic rate ( SMR ; determined in a respiration chamber ) ; 3 ) ( ADMR-SMR ) per kilogram of body mass ; and 4 ) the overall physical activity level ( PAL = ADMR/SMR ) . The highest correlation was found for the relationship between Tracmor output and PAL ( r = 0.58 ) . After correction for Tracmor values arising from vibrations produced by transportation means , this correlation was improved to 0.73 . There was no difference between Tracmor output and PAL in discriminating between overall activity levels with " low " ( PAL < 1.60 ) , " moderate " ( 1.60 < or = PAL < or = 1.85 ) , and " high " ( PAL > 1.85 ) intensity . It is concluded that the Tracmor can be used in free-living subjects to distinguish among interindividual as well as intraindividual levels of daily physical activity
For total EE , correlation coefficients were statistically significantly lower in uniaxial compared to multisensor devices .
For active EE , correlations were slightly but not significantly lower in uniaxial compared to triaxial and multisensor devices .
The high level of heterogeneity in the validation studies is only partly explained by the type of activity monitor and the activity monitor outcome .
Triaxial and multisensor devices tend to be more valid monitors .
The assessment of physical activity in healthy population s and in those with chronic diseases is challenging .
The aim of this systematic review was to identify whether available activity monitors ( AM ) have been appropriately vali date d for use in assessing physical activity in these groups .