title: Physical activity level and physical functionality in nonagenarians compared to individuals aged 60-74 years.
abstract: BACKGROUND
  Functional dependence and the risks of disability increase with age. The loss of independence is thought to be partially due to a decrease in physical activity. However, in populations, accurate measurement of physical activity is challenging and may not provide information on functional impairment.
  
  
  METHODS
  This study therefore assessed physical functionality and physical activity level in a group of nonagenarians (11 men/11 women; 93+/-1 years, 66.6+/-2.4 kg, body mass index [BMI]=24+/-1 kg/m2) and a group of participants aged 60-74 years (17 men/15 women; 70+/-1 years, 83.3+/-3.0 kg, BMI=29+/-1 kg/m2) from the Louisiana Healthy Aging Study. Physical activity level was calculated from total energy expenditure (TEE) and resting metabolic rate (RMR). Physical functionality was assessed using the Reduced Continuous Scale Physical Functional Performance Test (CS-PFP10).
  
  
  RESULTS
  Nonagenarians had lower absolute (p<.001) and adjusted (p<.007) TEE compared to participants aged 60-74 years which was attributed to a reduction in both RMR and physical activity level. Nonagenarians also had reduced functional performance (p<.001) which was correlated with activity level (r=0.68, p<.001).
  
  
  CONCLUSIONS
  When compared to individuals aged 60-74 years, 73% of the reduction in TEE in nonagenarians can be attributed to a reduction in physical activity level, the remaining being accounted for by a reduction in RMR. The reduced physical activity in nonagenarians is associated with less physical functionality. This study provides the first objective comparison of physical functionality and actual levels of physical activity in older individuals.
authors.affiliation: Pennington Biomedical Research Center, and Louisiana State University, Baton Rouge, LA 70808, USA.
authors.forename: Madlyn I
authors.initials: MI
authors.lastname: Frisard
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Fabre
authors.forename: Ryan D
authors.initials: RD
authors.lastname: Russell
authors.forename: Christina M
authors.initials: CM
authors.lastname: King
authors.forename: James P
authors.initials: JP
authors.lastname: DeLany
authors.forename: Robert H
authors.initials: RH
authors.lastname: Wood
authors.forename: Eric
authors.initials: E
authors.lastname: Ravussin
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D001481:Basal Metabolism; D001823:Body Composition; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D008145:Louisiana; D008297:Male; D008875:Middle Aged; D009043:Motor Activity