title: Muscle-power quality: does sex or race affect movement velocity in older adults?
abstract: To determine sex and race differences in muscle power per unit of muscle contraction, knee-extensor muscle power normalized for knee-extensor muscle volume was measured in 79 middle-aged and older adults (30 men and 49 women, age range 50-85 years). Results revealed that women displayed a 38% faster peak movement velocity than men and African Americans had a 14% lower peak movement velocity than Whites of a similar age when expressed per unit of involved muscle (p < .001). As expected, men exhibited greater knee-extensor strength and peak power per unit of muscle than women, but women had a faster knee- extension movement velocity per unit of muscle than men at the same relative strength level. Moreover, African Americans had greater knee-extensor muscle volume than Whites but exhibited lower knee-extensor strength and lower movement velocity per unit of muscle when tested at the same relative strength levels.
authors.affiliation: Dept. of Kinesiology, University of Maryland, College Park, MD, USA.
authors.forename: Neil A
authors.initials: NA
authors.lastname: Doldo
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Delmonico
authors.forename: Jason A
authors.initials: JA
authors.lastname: Bailey
authors.forename: Brian D
authors.initials: BD
authors.lastname: Hand
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Kostek
authors.forename: Karma M
authors.initials: KM
authors.lastname: Rabon-Stith
authors.forename: Kalapurakkal S
authors.initials: KS
authors.lastname: Menon
authors.forename: Joan M
authors.initials: JM
authors.lastname: Conway
authors.forename: Craig R
authors.initials: CR
authors.lastname: Carignan
authors.forename: Ben F
authors.initials: BF
authors.lastname: Hurley
mesh_terms: D001741:Black or African American; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D005260:Female; D006801:Humans; D007717:Knee / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000502:physiology*; D012737:Sex Factors; D044465:White People