title: Echo intensity is associated with skeletal muscle power and cardiovascular performance in elderly men.
abstract: The purpose of the present study was to investigate the relationship between echo intensity, neuromuscular and cardiorespiratory performances in the elderly. Thirty-one healthy elderly men (65.5±5.0) participated in this study. Echo intensity of rectus femoris and quadriceps femoris muscle thicknesses was determined by ultrasound images. Lower-body isometric and isokinetic peak torques (60, 180 and 360°(.s-1)), as well as rate of force development were evaluated as strength parameters. In addition, torque per unit of muscle mass was evaluated by the quotient between isometric peak torque of the knee extensors and the quadriceps femoris muscle thickness. The peak oxygen uptake (VO(2peak)), maximum aerobic workload (W(máx)), absolute (VT(1) and VT(2)) ventilatory thresholds, as well as workloads at VT(1) and VT(2) (W(VT1) and W(VT2)) were evaluated during a maximal incremental test on a cycle ergometer. There were significant negative correlations between the individual values of echo intensity with the corresponding individual values of isometric and isokinetic peak torques (60, 180 and 360°(.s-1)) (r=-0.48 to r=-0.64; P<0.05), as well as with W(VT1) (r=-0.46) and W(VT2) (r=-0.50) (P<0.05). In addition, significant positive correlations were observed between torque per unit of muscle mass and cardiovascular parameters (r=0.52 to r=0.60; P<0.001). The present results suggest that the echo intensity analysis using computer-aided gray-scale analysis is a low cost, easily accessible, and a safe method to evaluate the muscle quality, and may contribute to the research of neuromuscular and cardiovascular performances in the elderly.
authors.affiliation: Exercise Research Laboratory, Physical Education School, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil. edcadore@yahoo.com.br
authors.forename: Eduardo Lusa
authors.initials: EL
authors.lastname: Cadore
authors.forename: Mikel
authors.initials: M
authors.lastname: Izquierdo
authors.forename: Matheus
authors.initials: M
authors.lastname: Conceição
authors.forename: Régis
authors.initials: R
authors.lastname: Radaelli
authors.forename: Ronei Silveira
authors.initials: RS
authors.lastname: Pinto
authors.forename: Bruno Manfredini
authors.initials: BM
authors.lastname: Baroni
authors.forename: Marco Aurélio
authors.initials: MA
authors.lastname: Vaz
authors.forename: Cristine Lima
authors.initials: CL
authors.lastname: Alberton
authors.forename: Stephanie Santana
authors.initials: SS
authors.lastname: Pinto
authors.forename: Giovani
authors.initials: G
authors.lastname: Cunha
authors.forename: Martim
authors.initials: M
authors.lastname: Bottaro
authors.forename: Luiz Fernando Martins
authors.initials: LF
authors.lastname: Kruel
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007719:Knee Joint / Q000502:physiology; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology; D055070:Resistance Training; D019415:Torque; D014463:Ultrasonography