title: Muscle contractile properties as an explanation of the higher mean power output in marmosets than humans during jumping.
abstract: The muscle mass-specific mean power output (PMMS,mean) during push-off in jumping in marmosets (Callithrix jacchus) is more than twice that in humans. In the present study it was tested whether this is attributable to differences in muscle contractile properties. In biopsies of marmoset m. vastus lateralis (VL) and m. gastrocnemius medialis (GM) (N=4), fibre-type distribution was assessed using fluorescent immunohistochemistry. In single fibres from four marmoset and nine human VL biopsies, the force-velocity characteristics were determined. Marmoset VL contained almost exclusively fast muscle fibres (>99.0%), of which 63% were type IIB and 37% were hybrid fibres, fibres containing multiple myosin heavy chains. GM contained 9% type I fibres, 44% type IIB and 47% hybrid muscle fibres. The proportions of fast muscle fibres in marmoset VL and GM were substantially larger than those reported in the corresponding human muscles. The curvature of the force-velocity relationships of marmoset type IIB and hybrid fibres was substantially flatter than that of human type I, IIA, IIX and hybrid fibres, resulting in substantially higher muscle fibre mass-specific peak power (PFMS,peak). Muscle mass-specific peak power output (PMMS,peak) values of marmoset whole VL and GM, estimated from their fibre-type distributions and force-velocity characteristics, were more than twice the estimates for the corresponding human muscles. As the relative difference in estimated PMMS,peak between marmosets and humans is similar to that of PMMS,mean during push-off in jumping, it is likely that the difference in in vivo mechanical output between humans and marmosets is attributable to differences in muscle contractile properties.
authors.affiliation: MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorstraat 9, Amsterdam NL-1081 BT, The Netherlands School of Healthcare Science, Cognitive Motor Function Research Group, School of Healthcare Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
authors.forename: Rogier L C
authors.initials: RL
authors.lastname: Plas
authors.affiliation: School of Healthcare Science, Cognitive Motor Function Research Group, School of Healthcare Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
authors.forename: Hans
authors.initials: H
authors.lastname: Degens
authors.affiliation: MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorstraat 9, Amsterdam NL-1081 BT, The Netherlands School of Healthcare Science, Cognitive Motor Function Research Group, School of Healthcare Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
authors.forename: J Peter
authors.initials: JP
authors.lastname: Meijer
authors.affiliation: MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorstraat 9, Amsterdam NL-1081 BT, The Netherlands.
authors.forename: Gerard M J
authors.initials: GM
authors.lastname: de Wit
authors.affiliation: Department of Immunobiology, Division Neuropathology, Biomedical Primate Research Centre, Rijswijk, The Netherlands.
authors.forename: Ingrid H C H M
authors.initials: IH
authors.lastname: Philippens
authors.affiliation: MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorstraat 9, Amsterdam NL-1081 BT, The Netherlands.
authors.forename: Maarten F
authors.initials: MF
authors.lastname: Bobbert
authors.affiliation: MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorstraat 9, Amsterdam NL-1081 BT, The Netherlands r.t.jaspers@vu.nl.
authors.forename: Richard T
authors.initials: RT
authors.lastname: Jaspers
mesh_terms: D000328:Adult; D000818:Animals; D001696:Biomechanical Phenomena; D002144:Callithrix / Q000502:physiology*; D005260:Female; D006801:Humans; D008124:Locomotion; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018485:Muscle Fibers, Skeletal / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000502:physiology*; D018995:Myosin Heavy Chains / Q000378:metabolism
chemical_list: D018995:Myosin Heavy Chains
keywords: Comparative physiology; Force–velocity relationship; Immunohistochemistry; Muscle fibre-type distribution; Muscle mass-specific power; Myosin heavy chain; Primate; Single muscle fibre; Skinned muscle fibre