Page 51 - Sember, Vedrana, and Shawnda A. Morrison. 2018. The Mind-Body Connection. Koper: University of Primorska Press.
P. 51
Quantifying Physical Activity
the implementation of activities in daily living environment. The
method assesses the energy consumption with an accuracy of 1–3%
depending on the results of calorimetry (Speakman, Nair, & Goran,
1993) and variability of the measurement is between 4–10% (Speak-
man, 1998). DLW is noncalorimetric technique for measuring total
energy expenditure (TEE) using an oral dose of water which con-
tains nonradioactive isotopes of hydrogen (2H) and oxygen (18O).
Derived CO2, as a product of physical activity, and indirect calori-
metry formulas are used to calculate energy expenditure. Physical
activity energy expenditure can be calculated knowing total daily
energy expenditure (TEE) measured by DLW, resting energy ex-
penditure (REE) and thermic effect of consumed food (TEF), meas-
ured by indirect calorimetry (Starling et al., 1999; Plasqui & West-
erterp, 2007). Measurement period normally runs from 1–3 weeks.
Samples isotopes may be sampled from all body fluids, but is the
most commonly used urine (Volmut, 2014).
AEE (kcal/day) = TEE (kcal/day) – REE (kcal/day).
Disadvantage of DLW technique is high cost, because of the relat-
ively high price of the oxygen-18 water, mass spectrometer instru-
mentation and specific technical expertise in sample preparation
and measurement (Starling et al., 1999). Despite being the criterion
for gold standard, DLW does not provide specific information about
daily physical activity, such as activity type, intensity and duration.
Taken into consideration all these limitations, DLW is used in sci-
entific manner to validate other techniques and approaches for the
quantification of free-living energy expenditure (Westerterp, 2009).
Multi-Sensor Devices. Measuring all aspects of physical activity un-
der free-living conditions is complex; the use of multiple methods
of assessing physical activity simultaneously is recommended. Ac-
celerometer and heart-rate monitor together make a powerful tool
for assessing energy expenditure. Accelerometer counts verify that
elevations in heart-rate are because of increased physical activity
or vice versa. Technology has moved on, so new wearable devices
are produced. Actiheart (CamNtech Ltd, Cambridge, UK) com-
bines heart-rate and accelerometry (Zakeri, Adolph, Puyau, Vohra,
49
the implementation of activities in daily living environment. The
method assesses the energy consumption with an accuracy of 1–3%
depending on the results of calorimetry (Speakman, Nair, & Goran,
1993) and variability of the measurement is between 4–10% (Speak-
man, 1998). DLW is noncalorimetric technique for measuring total
energy expenditure (TEE) using an oral dose of water which con-
tains nonradioactive isotopes of hydrogen (2H) and oxygen (18O).
Derived CO2, as a product of physical activity, and indirect calori-
metry formulas are used to calculate energy expenditure. Physical
activity energy expenditure can be calculated knowing total daily
energy expenditure (TEE) measured by DLW, resting energy ex-
penditure (REE) and thermic effect of consumed food (TEF), meas-
ured by indirect calorimetry (Starling et al., 1999; Plasqui & West-
erterp, 2007). Measurement period normally runs from 1–3 weeks.
Samples isotopes may be sampled from all body fluids, but is the
most commonly used urine (Volmut, 2014).
AEE (kcal/day) = TEE (kcal/day) – REE (kcal/day).
Disadvantage of DLW technique is high cost, because of the relat-
ively high price of the oxygen-18 water, mass spectrometer instru-
mentation and specific technical expertise in sample preparation
and measurement (Starling et al., 1999). Despite being the criterion
for gold standard, DLW does not provide specific information about
daily physical activity, such as activity type, intensity and duration.
Taken into consideration all these limitations, DLW is used in sci-
entific manner to validate other techniques and approaches for the
quantification of free-living energy expenditure (Westerterp, 2009).
Multi-Sensor Devices. Measuring all aspects of physical activity un-
der free-living conditions is complex; the use of multiple methods
of assessing physical activity simultaneously is recommended. Ac-
celerometer and heart-rate monitor together make a powerful tool
for assessing energy expenditure. Accelerometer counts verify that
elevations in heart-rate are because of increased physical activity
or vice versa. Technology has moved on, so new wearable devices
are produced. Actiheart (CamNtech Ltd, Cambridge, UK) com-
bines heart-rate and accelerometry (Zakeri, Adolph, Puyau, Vohra,
49
