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Objective: This study was undertaken in order to provide new insight into sensorimotor control of posture when wearing high-shaft (HS) boots as ski boots. Background: Previous studies into the effects of HS boots on postural control have produced controversial results. Some studies reported postural control impairments with ski boots in bipedal postural tasks due to ankle movement restrictions without quantifying the actual restrictive effect of these boots and specifying the adaptations of the postural control system. Method: Eighteen young healthy subjects took part in the experiment. Bilateral postural control was assessed on stable and unstable surfaces, while standing barefoot or wearing ski boots. Center of pressure (COP) parameters, ankle, knee, and hip joints movements were calculated and EMG activity from main postural muscles was recorded. Results: Ski boots did not restrict the amplitude of ankle angular movements and largely impacted COP parameters and EMG activity on stable ground. In conditions of mediolateral instability, COP data illustrated an enhanced postural control in the frontal plane when wearing ski boots. Conclusions: Ski boots do not affect bipedal postural balance by restricting the ankle angular motions but induce complex adaptations of the postural control system which combine factors of a mechanical, motor, and sensorial nature. They impede postural control mainly when standing on stable ground without producing similar deleterious effects on unstable surfaces. Application: Our results show that HS boots as ski boots can improve lateral balance on unstable surfaces, which can contribute to prevent fall risk and ankle sprain.

Despesa energètica; Telèfon intel·ligent; Lesió de la medul·la espinal ; Gasto energético; Teléfono inteligente; Lesión de la médula espinal ; Energy expenditure; Smartphone; Spinal cord injury ; This study aimed to investigate the validity of using built-in smartphone accelerometers to estimate the active energy expenditures of full-time manual wheelchair users with spinal cord injury (SCI). Twenty participants with complete SCI completed 10 5-min daily activities that involved the upper limbs, during which their oxygen consumption and upper limb activity were registered using a portable gas analyzer and a smartphone (placed on the non-dominant arm), respectively. Time series of 1-min averaged oxygen consumption and 55 accelerometer variables (13 variables for each of the four axes and three additional variables for the correlations between axes) were used to estimate three multiple linear models, using a 10-fold cross-validation method. The results showed that models that included either all variables and models or that only included the linear variables showed comparable performance, with a correlation of 0.72. Slightly worse general performance was demonstrated by the model that only included non-linear variables, although it proved to be more accurate at estimating the energy expenditures (EE) during specific tasks. These results suggest that smartphones could be a promising low-cost alternative to laboratory-grade accelerometers to estimate the energy expenditure of wheelchair users with spinal cord injury during daily activities. ; This work was supported by Fundació la Marató de la TV3, under Projects 201720-10 and 201701-10, and European Union through the Operational Program of the European Regional Development Fund (ERDF) of the Valencian Community 2014-2020 (IDIFEDER/2018/029).

[EN] This study aimed to investigate the validity of using built-in smartphone accelerometers to estimate the active energy expenditures of full-time manual wheelchair users with spinal cord injury (SCI). Twenty participants with complete SCI completed 10 5-min daily activities that involved the upper limbs, during which their oxygen consumption and upper limb activity were registered using a portable gas analyzer and a smartphone (placed on the non-dominant arm), respectively. Time series of 1-min averaged oxygen consumption and 55 accelerometer variables (13 variables for each of the four axes and three additional variables for the correlations between axes) were used to estimate three multiple linear models, using a 10-fold cross-validation method. The results showed that models that included either all variables and models or that only included the linear variables showed comparable performance, with a correlation of 0.72. Slightly worse general performance was demonstrated by the model that only included non-linear variables, although it proved to be more accurate at estimating the energy expenditures (EE) during specific tasks. These results suggest that smartphones could be a promising low-cost alternative to laboratory-grade accelerometers to estimate the energy expenditure of wheelchair users with spinal cord injury during daily activities. ; This work was supported by Fundacio la Marato de la TV3, under Projects 201720-10 and 201701-10, and European Union through the Operational Program of the European Regional Development Fund (ERDF) of the Valencian Community 2014-2020 (IDIFEDER/2018/029) ; Marco-Ahulló, A.; Montesinos-Magraner, L.; Gonzalez, L.; Llorens Rodríguez, R.; Segura-Navarro, X.; García-Massó, X. (2021). Validation of Using Smartphone Built-In Accelerometers to Estimate the Active Energy Expenditures of Full-Time Manual Wheelchair Users with Spinal Cord Injury. Sensors. 21(4):1-9. https://doi.org/10.3390/s21041498 ; S ; 1 ; 9 ; 21 ; 4

This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness and the European Regional Development Fund [grant no. DEP2016-75598-R, MINECO/FEDER, UE]. Additionally, this study takes place thanks to the funding from the University of Granada Plan Propio de Investigacion 2016 -Excellence actions: Unit of Excellence on Exercise and Health (UCEES) -and the Junta de Andalucia, Consejeria de Conocimiento, Investigacion y Universidades, European Regional Development Fund [grant no. SOMM17/6107/UGR]. The funding body had no role in the study design or collection, analysis, or interpretation of the data or in writing the manuscript. ; Background Literature focusing on youth has reported limited evidence and non-conclusive associations between neighborhood walkability measures and active commuting to and from school (ACS). Moreover, there is a lack of studies evaluating both macro- and micro-scale environmental factors of the neighborhood when ACS is analyzed. Likewise, most studies on built environment attributes and ACS focus on urban areas, whereas there is a lack of studies analyzing rural residential locations. Moreover, the relationship between built environment attributes and ACS may differ in children and adolescents. Hence, this study aimed to develop walkability indexes in relation to ACS for urban and rural children and adolescents, including both macro- and micro-scale school-neighborhood factors. Methods A cross-sectional study of 4593 participants from Spain with a mean age of 12.2 (SD 3.6) years was carried out. Macro-scale environmental factors were evaluated using geographic information system data, and micro-scale factors were measured using observational procedures. Socio-demographic characteristics and ACS were assessed with a questionnaire. Several linear regression models were conducted, including all the possible combinations of six or less built environment factors in order to find the best walkability index. Results Analyses showed that intersection density, number of four-way intersections, and residential density were positively related to ACS in urban participants, but negatively in rural participants. In rural children, positive streetscape characteristics, number of regulated crossings, traffic calming features, traffic lanes, and parking street buffers were also negatively related to ACS. In urban participants, other different factors were positively related to ACS: number of regulated crossings, positive streetscape characteristics, or crossing quality. Land use mix acted as a positive predictor only in urban adolescents. Distance to the school was a negative predictor on all the walkability indexes. However, aesthetic and social characteristics were not included in any of the indexes. Conclusions Interventions focusing on improving built environments to increase ACS behavior need to have a better understanding of the walkability components that are specifically relevant to urban or rural samples. ; Spanish Ministry of Economy, Industry and Competitiveness ; European Union (EU) DEP2016-75598-R ; University of Granada Plan Propio de Investigacion 2016 -Excellence actions: Unit of Excellence on Exercise and Health (UCEES) ; Junta de Andalucia, Consejeria de Conocimiento, Investigacion y Universidades, European Regional Development Fund SOMM17/6107/UGR