Abdominal MusclesMusclesMuscle, SkeletalRectus AbdominisMuscle ContractionMuscle ProteinsRespiratory MusclesElectromyographyMuscle, SmoothDiaphragmMuscle Fibers, SkeletalMuscle, Smooth, VascularMuscle DevelopmentMuscle FatigueIntercostal MusclesIntercostal NervesAbdominal WallPressureRespiratory MechanicsAbdomenMuscle Fibers, Fast-TwitchMuscle DenervationMuscle RelaxationMuscle Fibers, Slow-TwitchPostureRespirationMyocytes, Smooth MuscleMitochondria, MuscleInhalationNephropidaePositive-Pressure Respiration, IntrinsicIsometric ContractionNeck MusclesOculomotor MusclesMuscle, StriatedAbdominal CavityMuscle SpindlesLordosisThoraxMuscle WeaknessPapillary MusclesLaryngeal MusclesQuadriceps MuscleLumbosacral RegionMuscle CellsExhalationBiomechanical PhenomenaHypercapniaElectric StimulationMasseter MuscleFacial MusclesMasticatory MusclesCoughMuscular AtrophyPelvisSatellite Cells, Skeletal MusclePhysical ExertionPulmonary VentilationMovementPectoralis MusclesLung Volume MeasurementsDogsRecruitment, NeurophysiologicalTime FactorsSupine PositionPatient PositioningMuscular DiseasesSpineAstacoideaLow Back PainPhrenic NerveExerciseStomachRats, Sprague-DawleySurgical Flaps