title: Skeletal Muscle Pump Drives Control of Cardiovascular and Postural Systems.
abstract: The causal interaction between cardio-postural-musculoskeletal systems is critical in maintaining postural stability under orthostatic challenge. The absence or reduction of such interactions could lead to fainting and falls often experienced by elderly individuals. The causal relationship between systolic blood pressure (SBP), calf electromyography (EMG), and resultant center of pressure (COPr) can quantify the behavior of cardio-postural control loop. Convergent cross mapping (CCM) is a non-linear approach to establish causality, thus, expected to decipher nonlinear causal cardio-postural-musculoskeletal interactions. Data were acquired simultaneously from young participants (25 ± 2 years, n = 18) during a 10-minute sit-to-stand test. In the young population, skeletal muscle pump was found to drive blood pressure control (EMG → SBP) as well as control the postural sway (EMG → COPr) through the significantly higher causal drive in the direction towards SBP and COPr. Furthermore, the effect of aging on muscle pump activation associated with blood pressure regulation was explored. Simultaneous EMG and SBP were acquired from elderly group (69 ± 4 years, n = 14). A significant (p = 0.002) decline in EMG → SBP causality was observed in the elderly group, compared to the young group. The results highlight the potential of causality to detect alteration in blood pressure regulation with age, thus, a potential clinical utility towards detection of fall proneness.
authors.affiliation: Department of Electrical Engineering, University of North Dakota, Grand Forks-58202, USA.
authors.forename: Ajay K
authors.initials: AK
authors.lastname: Verma
authors.affiliation: Department of Engineering Science, Simon Fraser University, Burnaby-V5A 1S6, Canada.
authors.forename: Amanmeet
authors.initials: A
authors.lastname: Garg
authors.affiliation: Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby-V5A 1S6, Canada.
authors.forename: Da
authors.initials: D
authors.lastname: Xu
authors.affiliation: Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby-V5A 1S6, Canada.
authors.forename: Michelle
authors.initials: M
authors.lastname: Bruner
authors.affiliation: Department of Electrical Engineering, University of North Dakota, Grand Forks-58202, USA.
authors.forename: Reza
authors.initials: R
authors.lastname: Fazel-Rezai
authors.affiliation: Department of Electrical Engineering, University of North Dakota, Grand Forks-58202, USA.|Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby-V5A 1S6, Canada.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Blaber
authors.affiliation: Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby-V5A 1S6, Canada.
authors.forename: Kouhyar
authors.initials: K
authors.lastname: Tavakolian
mesh_terms: D000058:Accidental Falls; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D002319:Cardiovascular System / Q000503:physiopathology*; D004576:Electromyography / Q000379:methods; D005260:Female; D006801:Humans; D018482:Muscle, Skeletal / Q000502:physiology*; D004856:Postural Balance / Q000502:physiology; D011187:Posture / Q000502:physiology*; D011312:Pressure