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 .
Assessment of energy expenditure in overweight women.
PURPOSE To compare field measures of average daily energy expenditure ( ADEE ) against criterion data by the doubly labeled water method ( DLW ) in overweight women . METHODS The subject were 20 overweight ( BMI 29.9 + a- 3.0 kg.m-2 ) premenopausal women .  Energy expenditure was measured by DLW and by the factorial method ( activity diary , two techniques differing by method to obtain resting energy expenditure , REE ) , heart-rate monitoring ( HR , two techniques differing by the FLEX-point to discriminate sedentary and activity HR ) , accelerometer , and pedometer . RESULTS The ADEE(DLW ) was 10.26 + a- 1.1 MJ.d-1 . The mean bias ( ADEE by the alternative minus ADEE(DLW ) was smallest for the accelerometer ( + 0.08 + a- 1.63 MJ ) and HR-FLEX10 ( + 0.11 + a- 1.67 MJ ) . The HR-FLEX(0 ) technique ( lower FLEX-point ) overestimated ADEE by + 1.18 ( + a- 1.97 MJ ) . However , the r and om error ( SD of bias ) was smaller for both factorial techniques ( REE measured : -0.48 + 2- 0.81 MJ ; REE calculated from the WHO equation : -0.22 + 2- 0.88 MJ ) . CONCLUSION The results show that simple factorial methods may assess ADEE with small r and om errors in population with a rather narrow range of physical activity . The accelerometer and HR with the higher FLEX-point have comparable results with smaller bias but larger r and om error compared with the factorial techniques
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 .