Caloric Expenditure Assessment Among

Older Adults Sarah T Stahl, and Salvatore P Insana

University of Pittsburgh, Pittsburgh, PA West Virginia University, Morgantown, WV

Caitlin Heffley Clinical Nutrition Student

Physical Activity !  Associated with

successful aging

!  Reduces the likelihood of chronic diseases

!  Increases functional health

!  Promotes social engagement

!  Better psychological health

Meisner et al.

The Issue ! What duration and intensity is

needed to produce a desired effect?

!  Need valid measurement tools

!  Difficulty with self report

!  CHAMPS Questionniare

!  Accelerometers

Purpose ! To examine the

validity of a new accelerometry device (Fitbit), by comparing the Fitbit-calculated kcal to subjective estimations of kcal using CHAMPS among a sample of healthy, older adults.

Hypothesis ! FitBit is a more accurate estimate of

kcal expenditure as a result of physical activity in older adults than CHAMPS.

Subjects !  Subjects recruited via email and word of mouth

from West Virginia University faculty and staff

!  16 adults volunteered to participate !  1 declined due to time constraints

!  2 lost the FitBit !  3 failed to transmit FitBit data to a computer

!  Disrupted data collection among 33% of the total sample

!  Received $25 for study compensation

Sample

!  Sample size: 10 adults !  60-68 years old (M=63.8, SD= 3.17 ) !  Men, married, employed at a University (educated)

!  Caucasian Health status !  BMI of 24.5 (SD= 4.17)

!  Health conditions include arthritis (50%), sleeping problems (50%), and hypertension (40%)

!  Scale of 1 (very good) to 6 (very poor) rated health as “good)

Methods Subjective measurement

!  CHAMPS !  Frequency and duration of 40 physical activities !  Each task assigned a MET (metabolic equivalent)

value !  BMR calculated using Harris-Benedict equation !  Total kcal/day measured

Methods (Objective)

!  FitBit !  Measures body movement !  Age, sex, height, weight

entered !  Wore device all waking

hours for 10 days

!  Kcal values averaged across 10 day period to obtain total kcal/day

Results !  CHAMPS data

!  Subjects engaged in 3.3 activities (SD=0.98) daily !  1.8 (SD=0.85) were moderate-intensity activities

!  Common activities: Light housework (80%) Walking to do errands (60%)

Walking leisurely for exercise/pleasure (60%) Walking hiking uphill (80%)

Heavy strength training (50%)

Results !  BMR= 1545.97 (SD = 272.66) kcal/day

!  Self-reported expending 708.12 (SD = 430.83) kcal/day in physical activities

!  Averaged total daily caloric expenditure (CHAMPS) was 2254.08 (SD = 574.53) kcal/day.

!  Averaged accelerometry-measured (FitBit) caloric expenditure was 2059.10 (SD = 315.35) kcal/day.

!  The Fitbit underestimated kcal/day by an average of 194.99 (SD = 459.21) kcal.

Discussion !  Fitbit

!  underestimated kcal/day among 70% of participants !  Overestimated kcal/day among 30% of participants

!  Future research needed with more diverse samples of older adult populations

Limitations:

!  Small homogenous sample, 33% lost to error

!  30% of data greater than 1 SD over mean the mean difference between measurement methods !  FitBit not specifically designed for older adults

Limitations !  Small homogenous sample, 33% lost to error !  30% of data greater than 1 SD over mean

!  FitBit not specifically designed for older adults !  Comparative validity studies needed

Questions