title: Biomechanical and biochemical properties of chicken calcaneal tendon under effect of age and nonforced active exercise.
abstract: This study investigated if nonforced active exercise alters the biomechanical and biochemical properties of calcaneal tendon during maturation. Chickens at 1, 5, and 8 months old were divided into two groups: caged and penned. Intact tendons were used for biomechanical analysis, but they were divided into tensile and compressive regions for quantification of hydroxyproline and glycosaminoglycans. The exercise increased tendon strength after the fifth month, energy absorption in the eighth month, and ultimate tensile stress in the first month. Age increased tendon strength and energy storage and reduced stiffness but did not alter stress. There was an increase in collagen content in the fifth month. Glycosaminoglycans showed a progressive decline in the tensile region. Thus, some biomechanical and biochemical changes depend on the maturation process itself and also are influenced by spontaneous exercise, showing that mechanical stimulation of low intensity may help to improve the quality of the tendon.
authors: Department of Cell Biology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil.
authors: Wilson Romero
authors: WR
authors: Nakagaki
authors: Adriano
authors: A
authors: Biancalana
authors: Gustavo Pereira
authors: GP
authors: Benevides
authors: Laurecir
authors: L
authors: Gomes
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001696:Biomechanical Phenomena; D002111:Calcaneus; D002645:Chickens; D003094:Collagen / Q000378:metabolism*; D004548:Elasticity; D006025:Glycosaminoglycans / Q000378:metabolism*; D006909:Hydroxyproline / Q000378:metabolism*; D005082:Physical Exertion; D013314:Stress, Mechanical; D013710:Tendons / Q000502:physiology*
chemical_list: D006025:Glycosaminoglycans; D003094:Collagen; D006909:Hydroxyproline