Functional reserve in functionally independent elderly persons: a calculation of gait speed and physiological cost

Abstract

Aim: To analyze the behavior of functional reserve percentage (%FR) by gender in functional elderly persons, considering speed and the physiological cost of gait. Methods: A total of 53 self-reliant elderly persons, 40 of whom were women (age 69.4±4.7 years old; BMI 31.2±4.3 kg/m 2 ) and 13 of whom were men (age 70.8±7.2 years old; BMI 28.7±3.5 kg/m 2 ) participated in an observational and cross-sectional study. Participants were requested to walk at comfortable (CG) and maximum gait (MG). Both modalities were performed on a 70-meter elliptical circuit over three minutes. Distance and working heart rate were recorded for the corresponding calculation of average gait speed (AGS), physiological cost index (PCI) and used working heart rate percentage (% uWHR). With this information the FR% was determined by the percentage ratio with AGS, PCI and %uWHR under comfortable versus maximum demand walk conditions. Results: The association between %FR and AGS was significantly higher in males (p=0.017), reaching values of +-20% in most subjects. The physiological %FR for PCI was ≈30% in both men and women (p=0.156), while for % uWHR was ≈40% in females and ≈45% in males (p=0.131). Conclusion: AGS is a critical threshold functionality indicator to determine FR in functionally independent Chilean elderly persons.

Functional reserve: The residual variance in instrumental activities of daily living not explained by brain structure, cognition, and demographics.

“…The term 'functional reserve' has been used to describe individual differences in reserve capacities of other aspects of everyday functioning in the context of aging. For instance, in studies of physical fitness, functional reserve has been separately operationalized to capture interindividual differences in one's capacity to mitigate cardiovascular health and musculoskeletal system deterioration (Goldspink, 2005) and to maintain physical fitness (González, Cofré, & Cabello, 2016). Functional reserve has also been operationalized as a variable to determine person-specific oxygen uptake values (Arnett, Laity, Agrawal, & Cress, 2008).…”

Comparison of distance covered, physiological cost, and perceived exertion in four six-minute walk test protocols

“…The differences in WD may be due to constant accelerations and decelerations in gait not occurring on the elliptical track, which are present on a straight track with a delimited length. In this respect, Medina et al (2016) proposed that gait be assessed in older adults on an elliptical track because this track would allow a gait pattern that would better resemble natural conditions, as opposed to a straight unidirectional track, where the displacement would be conditioned by turns. In this sense, Pinochet et al Indicate that the changes in direction that the subject undergoes during the turns on the one-way track cause the walking speed to decrease.…”

Composición Corporal y Capacidad Física en Pacientes con COVID-19 Hospitalizados en una Unidad de Cuidados Intensivos

“…Por otra parte, existió una relación entre la VelPC6m-MLG y la VelPC6m-MM de los miembros inferiores izquierdo y derecho. El análisis de la marcha basado en el estudio de las aceleraciones del cuerpo, entrega información sobre el grado de funcionalidad de los pacientes (Correia de Faria Santarém et al, 2015;Medina-González et al, 2016). De manera natural, el cuerpo desarrolla una disminución de la fuerza muscular que repercute en las distintas fases de la marcha.…”

“…Al respecto, una consecuencia de la estadía prolongada en la UCI y el uso de VM en pacientes con COVID-19, es el desarrollo de debilidad muscular (Gonzalez et al, 2020). Esta debilidad se desarrolla tanto en musculatura respiratoria como de los miembros apendiculares y su incidencia es de aproximadamente el 80 % en pacientes de la UCI y se asocia con una mayor duración en VM, hecho que deteriora la funcional de los sobrevivientes (Gonzalez et al, 2020;Medina-González et al, 2016). Además de esto, se ha observado en sujetos jóvenes sometidos a 4 semanas de suspensión unilateral de miembros inferiores un aumento significativo de la acumulación de grasa intramuscular y una disminución de los volúmenes musculares (Manini et al, 2007).…”

“…Se llevó a cabo en un pasillo de 30 metros de largo, libre de tráfico. Se instruyó a los pacientes a recorrer la mayor cantidad de metros posibles durante los seis minutos correspondiente (Medina-González et al, 2016). La oximetría de pulso y la frecuencia cardiaca fueron medidos al inicio y al final de la prueba por un oxímetro marca (Ohmeda Biox 3740®) (Muñoz-Cofré et al, 2016).…”