title: Attenuated maximal muscle strength and peak power in children with sickle cell disease.
abstract: Dominant hand maximal handgrip strength evaluated with a handgrip dynamometer and peak power evaluated with a force plate, adjusted for body size and composition, were compared in African-American children aged 5 to 13 years, with and without type SS sickle cell disease (SCD-SS). Children with SCD-SS (n = 35; age, 9.0 ± 2.0 y) compared with healthy control children (n = 103; age, 8.6 ± 1.8 y) did not differ by age, sex, or pubertal status, yet had significantly lower Z scores for height, weight, body mass index, upper arm muscle area, upper arm fat area, fat mass-for-height and lean mass-for-height. Children with SCD-SS had significantly lower handgrip strength (12.7 ± 3.3 vs. 15.2 ± 5.1 kg, P < 0.008), peak power (882 ± 298 vs. 1167 ± 384 W, P < 0.001), and growth and body composition adjusted Z scores for handgrip strength (0.6 ± 1.3 standard deviations, P < 0.004) and peak power (male children = 1.0 ± 0.8 standard deviations, P < 0.0002; female children = 1.0 ± 1.7 standard deviations, P < 0.006). Maximal muscle strength and peak power are attenuated in children with SCD-SS compared with healthy control children beyond expectation for growth and body composition deficits suggesting that additional factors contribute to attenuation in anaerobic performance.
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, PA 19104, USA. doughertyk@email.chop.edu
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Dougherty
authors.forename: Joan I
authors.initials: JI
authors.lastname: Schall
authors.forename: Alisha J
authors.initials: AJ
authors.lastname: Rovner
authors.forename: Virginia A
authors.initials: VA
authors.lastname: Stallings
authors.forename: Babette S
authors.initials: BS
authors.lastname: Zemel
mesh_terms: D000293:Adolescent; D001741:Black or African American; D000755:Anemia, Sickle Cell / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology*