title: Effects of static and dynamic training on the stiffness and blood volume of tendon in vivo.
abstract: The purpose of this study was to investigate the effects of static and dynamic training on the stiffness and blood volume of the human tendon in vivo. Ten subjects completed 12 wk (4 days/wk) of a unilateral training program for knee extensors. They performed static training on one side [ST; 70% of maximum voluntary contraction (MVC)] and dynamic training on the other side (DT; 80% of one repetition maximum). Before and after training, MVC, neural activation level (by interpolated twitch), muscle volume (by magnetic resonance imaging), stiffness of tendon-aponeurosis complex and patella tendon (by ultrasonography), and blood volume of patella tendon (by red laser lights) were measured. Both protocols significantly increased MVC (49% for ST, 32% for DT; both P < 0.001), neural activation level (9.5% for ST, 7.6% for DT; both P < 0.01), and muscle volume (4.5% for ST, 5.6% for DT; both P < 0.01). The stiffness of tendon-aponeurosis complex increased significantly after ST (55%; P = 0.003) and DT (30%; P = 0.033), while the stiffness of patella tendon increased significantly after ST (83%; P < 0.001), but not for DT (P = 0.110). The blood volume of patella tendon increased significantly after DT (47%; P = 0.016), but not for ST (P = 0.205). These results implied that the changes in the blood volume of tendon would be related to differences in the effects of resistance training on the tendon properties.
authors.affiliation: Deptartment of Life Science, Sports Sciences Univ. of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan. kubo@idaten.c.u-tokyo.ac.jp
authors.forename: Keitaro
authors.initials: K
authors.lastname: Kubo
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Ikebukuro
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Yaeshima
authors.forename: Hideaki
authors.initials: H
authors.lastname: Yata
authors.forename: Naoya
authors.initials: N
authors.lastname: Tsunoda
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kanehisa
mesh_terms: D001810:Blood Volume; D004548:Elasticity; D004558:Electric Stimulation; D004576:Electromyography; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009119:Muscle Contraction; D053580:Muscle Strength; D009929:Organ Size; D017847:Patellar Ligament / Q000000981:diagnostic imaging / Q000294:innervation / Q000502:physiology*; D052097:Quadriceps Muscle / Q000000981:diagnostic imaging / Q000294:innervation / Q000502:physiology*; D055070:Resistance Training; D014463:Ultrasonography; D055815:Young Adult