115 research outputs found
Commentary on Olvera et al.’s Article Entitled, “Physical Activity in Latino Children: Research and Its Implications”
The following is a commentary on an article discussing physical activity in Latino children. It is clear that research is needed to determine the causes of inactivity and develop effective strategies for promoting physical activity in this population. Approaches involving numerous community entities (faith-based, businesses) and the implementation of policies that enhance physical activity participation appear very promising
Improving Brain–Machine Interface Performance by Decoding Intended Future Movements
Objective. A brain–machine interface (BMI) records neural signals in real time from a subject\u27s brain, interprets them as motor commands, and reroutes them to a device such as a robotic arm, so as to restore lost motor function. Our objective here is to improve BMI performance by minimizing the deleterious effects of delay in the BMI control loop. We mitigate the effects of delay by decoding the subject\u27s intended movements a short time lead in the future. Approach. We use the decoded, intended future movements of the subject as the control signal that drives the movement of our BMI. This should allow the user\u27s intended trajectory to be implemented more quickly by the BMI, reducing the amount of delay in the system. In our experiment, a monkey (Macaca mulatta) uses a future prediction BMI to control a simulated arm to hit targets on a screen. Main Results. Results from experiments with BMIs possessing different system delays (100, 200 and 300 ms) show that the monkey can make significantly straighter, faster and smoother movements when the decoder predicts the user\u27s future intent. We also characterize how BMI performance changes as a function of delay, and explore offline how the accuracy of future prediction decoders varies at different time leads. Significance. This study is the first to characterize the effects of control delays in a BMI and to show that decoding the user\u27s future intent can compensate for the negative effect of control delay on BMI performance
Small Business Support of Youth Physical Activity
Comparative Medicine - OneHealth and Comparative Medicine Poster SessionBackground: Increasing the number of youth physical activity opportunities (YPAO) (e.g., programs) may be a promising approach for encouraging physically active lifestyles among youth. To do this effectively, we need information on YPAO support systems (e.g., types [financial, in-kind]). Objective: To construct a comprehensive description of YPAO support systems with a focus on the involvement of small businesses. Methods: The first aim was to obtain detailed information about YPAO available to the public including their characteristics (e.g., amenities), operating costs, and the sources of support for the operating costs. The second aim was to describe characteristics related to supporting YPAO. Data from four minority (>70% minority) and four non-minority (<10% minority), inner-city Kansas City neighborhoods was obtained over an eight-month period using quantitative (e.g., surveys, community tours) and qualitative (e.g., key informants) data collection methods. Results: Of the 55 small businesses surveyed, those whose owner was middle-aged (40-50 y), white, with a sports background, and children between 5 and 16 years old were more likely to support YPAO. Only 33% of the business owners surveyed supported YPAO and less than 1% did this to advertise their business. Although YPAO support levels were low, all owners (supporters and non-supporters of YPAO) believed small businesses should support YPAO and how such support can make a difference in the neighborhood. Three main themes emerged regarding the culture of support. First, business owners were more apt to offer support for YPAO if family and friends were involved. Second, business owners tended to be aware of and offer support for broad initiatives focused on neighborhood improvements but experienced barriers to specifically supporting YPAO. For example, information about YPAO needing support was not readily available and few organizations soliciting support for neighborhood initiatives allowed for specific initiatives (e.g., YPAO) to be selected. Third, prominent stakeholders within a neighborhood heavily influenced the culture of giving which suggests they could be used to champion support for YPAO from small businesses. Several barriers to supporting YPAO by small businesses were identified. Small business owners did not track how their support was used and therefore did not receive feedback on the impact of their support. Credit was seldom given to small businesses for their support negating possible returns on their investments (e.g., positive exposure leading to increased business). Owners had little knowledge of who needed help and why they needed help within the neighborhood where their business was located, thus they did not know who or what cause to support. Some owners were not willing to give support because they did not trust the population of the neighborhood where their business was located and did not believe the support would be used for legitimate purposes. This was particularly true for non-minority business owners with a business in a minority neighborhood. Conclusions: Characteristics of small business owners, cultural trends regarding support, and the existence of modifiable barriers to support were identified that may help in the formulation of partnerships to promote youth physical activity
The Effect of Habitual Smoking on VO2max
VO2max is associated with many factors, including age, gender, physical activity, and body composition. It is popularly believed that habitual smoking lowers aerobic fitness. PURPOSE: to determine the effect of habitual smoking on VO2max after controlling for age, gender, activity and BMI. METHODS: 2374 men and 375 women employed at the NASA/Johnson Space Center were measured for VO2max by indirect calorimetry (RER>=1.1), activity by the 11 point (0-10) NASA Physical Activity Status Scale (PASS), BMI and smoking pack-yrs (packs day*y of smoking). Age was recorded in years and gender was coded as M=1, W=0. Pack.y was made a categorical variable consisting of four levels as follows: Never Smoked (0), Light (1-10), Regular (11-20), Heavy (>20). Group differences were verified by ANOVA. A General Linear Models (GLM) was used to develop two models to examine the relationship of smoking behavior on VO2max. GLM #1(without smoking) determined the combined effects of age, gender, PASS and BMI on VO2max. GLM #2 (with smoking) determined the added effects of smoking (pack.y groupings) on VO2max after controlling for age, gender, PASS and BMI. Constant errors (CE) were calculated to compare the accuracy of the two models for estimating the VO2max of the smoking subgroups. RESULTS: ANOVA affirmed the mean VO2max of each pack.y grouping decreased significantly (p<0.01) as the level of smoking exposure increased. GLM #1 showed that age, gender, PASS and BMI were independently related with VO2max (R2 = 0.642, SEE = 4.90, p<0.001). The added pack.y variables in GLM #2 were statistically significant (R2 change = 0.7%, p<0.01). Post hoc analysis showed that compared to Never Smoked, the effects on VO2max from Light and Regular smoking habits were -0.83 and -0.85 ml.kg- 1.min-1 respectively (p<0.05). The effect of Heavy smoking on VO2max was -2.56 ml.kg- 1.min-1 (p<0.001). The CE s of each smoking group in GLM #2 was smaller than the CE s of the smoking group counterparts in GLM #1. CONCLUSIONS: After accounting for the effects of gender, age, PASS and BMI the effect of habitual smoking on reducing VO2max is minimal, about 0.85 ml/kg/min, until the habit exceeds 20 pack.y at which point an additional decrease of 1.71 ml/kg/min is noted. Adding pack.y data improves the accuracy of predicting the VO2max of smokers
Associations between the built environment and physical activity in public housing residents
Background: Environmental factors may influence the particularly low rates of physical activity in African American and low-income adults. This cross-sectional study investigated how measured environmental factors were related to self-reported walking and vigorous physical activity for residents of low-income public housing developments.
Methods: Physical activity data from 452 adult residents residing in 12 low-income housing developments were combined with measured environmental data that examined the neighborhood (800 m radius buffer) around each housing development. Aggregated ecological and multilevel regression models were used for analysis.
Results: Participants were predominately female (72.8%), African American (79.6%) and had a high school education or more (59.0%). Overall, physical activity rates were low, with only 21% of participants meeting moderate physical activity guidelines. Ecological models showed that fewer incivilities and greater street connectivity predicted 83% of the variance in days walked per week, p < 0.001, with both gender and connectivity predicting days walked per week in the multi-level analysis, p < 0.05. Greater connectivity and fewer physical activity resources predicted 90% of the variance in meeting moderate physical activity guidelines, p < 0.001, and gender and connectivity were the multi-level predictors, p < 0.05 and 0.01, respectively. Greater resource accessibility predicted 34% of the variance in days per week of vigorous physical activity in the ecological model, p < 0.05, but the multi-level analysis found no significant predictors.
Conclusion: These results indicate that the physical activity of low-income residents of public housing is related to modifiable aspects of the built environment. Individuals with greater access to more physical activity resources with few incivilities, as well as, greater street connectivity, are more likely to be physically active
Organizational Culture and Implications for Workplace Interventions to Reduce Sitting Time Among Office-Based Workers: A Systematic Review
Background: Time spent in sedentary behaviors is an independent risk factor for several chronic diseases (e.g., cardiometabolic diseases, obesity, type 2 diabetes, and hypertension). Recently, interventions to reduce sitting time at work (a prominent sedentary behavior) have been developed and tested. Organizational culture plays a critical role in the success of workplace interventions. However, there are a limited number of studies that have examined the role of organizational culture in reducing sitting time in the workplace.Objectives: Therefore, in this systematic review, we summarized the empirical literature investigating organizational culture and sedentary behavior in the workplace and identify gaps in the knowledge base.Methods: We described the procedures of our systematic review and included two study flow diagrams that detailed the step by step process. Combinations of several search terms were used; the databases searched were PubMed, Medline, Academic Search Complete, and Google Scholar. We started with thousands of citations. After applying the inclusion and exclusion criteria, eight relevant articles were identified.Results: For each identified article, the data extracted included citation, sample, objective, intervention, assessment of organizational culture and workplace sitting, findings, and implications. Each article was rated for risk of bias by population, intervention, comparator, outcomes, and study design (PICOS) analysis. The classification for each study was either: high-, moderate-, or low-quality evidence. Given the paucity of data, no definitive conclusions were presented; however, positive trends were highlighted.Conclusions: Work place interventions to reduce sitting time at work may benefit from considering elements of organizational culture; however, the evidence to date is sparse and more high-quality studies in this area are needed. To advance the field of workplace health promotion, organizational culture, and interventions to reduce sitting at work, we present 11 recommendations
Dietary Supplements and Sports Performance: Amino Acids
This is the third in a series of six articles to discuss the major classes of dietary supplements (vitamins; minerals; amino acids; herbs or botanicals; metabolites, constituents/extracts, or combinations). The major focus is on efficacy of such dietary supplements to enhance exercise or sport performance
Assessing the influence of the built environment on physical activity for utility and recreation in suburban metro Vancouver
<p>Abstract</p> <p>Background</p> <p>Physical inactivity and associated co-morbidities such as obesity and cardiovascular disease are estimated to have large societal costs. There is increasing interest in examining the role of the built environment in shaping patterns of physical activity. However, few studies have: (1) simultaneously examined physical activity for leisure and utility; (2) selected study areas with a range of built environment characteristics; and (3) assessed the built environment using high-resolution land use data.</p> <p>Methods</p> <p>Data on individuals used for this study are from a survey of 1602 adults in selected sites across suburban Metro Vancouver. Four types of physical activity were assessed: walking to work/school, walking for errands, walking for leisure and moderate physical activity for exercise. The built environment was assessed by constructing one-kilometre road network buffers around each respondent's postal code. Measures of the built environment include terciles of recreational and park land, residential land, institutional land, commercial land and land use mix.</p> <p>Results</p> <p>Logistic regression analyses showed that walking to work/school and moderate physical activity were not associated with any built environment measure. Living in areas with lower land use mix, lower commercial and lower recreational land increased the odds of low levels of walking for errands. Individuals living in the lower third of land use mix and institutional land were more likely to report low levels of walking for leisure.</p> <p>Conclusions</p> <p>These results suggest that walking for errands and leisure have a greater association with the built environment than other dimensions of physical activity.</p
Determinants of the Incidence of Hand, Foot and Mouth Disease in China Using Geographically Weighted Regression Models
Child population density and climate factors are potential determinants of the HFMD incidence in most areas in China. The strength and direction of association between these factors and the incidence of HFDM is spatially heterogeneous at the local geographic level, and child population density has a greater influence on the incidence of HFMD than the climate factors
Motor Adaptation Scaled by the Difficulty of a Secondary Cognitive Task
Background: Motor learning requires evaluating performance in previous movements and modifying future movements. The executive system, generally involved in planning and decision-making, could monitor and modify behavior in response to changes in task difficulty or performance. Here we aim to identify the quantitative cognitive contribution to responsive and adaptive control to identify possible overlap between cognitive and motor processes. Methodology/Principal Findings: We developed a dual-task experiment that varied the trial-by-trial difficulty of a secondary cognitive task while participants performed a motor adaptation task. Subjects performed a difficulty-graded semantic categorization task while making reaching movements that were occasionally subjected to force perturbations. We find that motor adaptation was specifically impaired on the most difficult to categorize trials. Conclusions/Significance: We suggest that the degree of decision-level difficulty of a particular categorization differentially burdens the executive system and subsequently results in a proportional degradation of adaptation. Our results suggest
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