title: Absolute vs. relative machine strength as predictors of function in older adults.
abstract: This study examined the relationship between absolute and relative (1 repetition maximum/LBM) strength vs. 13 different functional measurements in 143 older adults (mean = 70.28, standard deviation = 7.90 years). Strength for 11 machine lifts was determined using a predicted 1-repetition maximal strength measurement. Zero-order correlation results between absolute and relative strength vs. function measures demonstrated very weak to moderate correlations in the range of 0.02-0.57 and 0.01-0.44, respectively, with the lowest correlations present between strength and balance measures and the highest correlations present between strength and the carrying task (p </= 0.05). Stepwise multiple regression results also confirmed the low predictability of functional tasks using strength measures, with absolute and relative strength measures accounting for only 3-38% and 3-33% of the various functional measures, respectively. This study identified specific strength measurements that contribute to the variance in a functional task but also clearly indicated that strength alone cannot serve as a predictor of function in older adults.
authors.affiliation: Department of Physical Education, Health, and Recreation, Western Washington University, Bellingham, Washington 98225, USA. kathy.knutzen@wwu.edu
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Knutzen
authors.forename: Lorraine
authors.initials: L
authors.lastname: Brilla
authors.forename: Dennis
authors.initials: D
authors.lastname: Caine
authors.forename: Gordon
authors.initials: G
authors.lastname: Chalmers
authors.forename: Kathy
authors.initials: K
authors.lastname: Gunter
authors.forename: Philip
authors.initials: P
authors.lastname: Schot
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D008875:Middle Aged; D018908:Muscle Weakness; D018482:Muscle, Skeletal / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology*; D004856:Postural Balance; D011237:Predictive Value of Tests; D011336:Probability; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012737:Sex Factors; D013647:Task Performance and Analysis; D014891:Weight Lifting / Q000502:physiology*