Sandra C. Dorman

Examining school-based pedometer step counts among children in grades 3 to 6 using different timetables.

BACKGROUND Advocates for the implementation of the Balanced School Day (BSD) schedule argue that this schedule will increase opportunities for physical activity. However, the relationship between this scheduling change and its impact on physical activity has not been examined. Thus, this study assessed levels of physical activity in students attending 2 different schools: 1 using the BSD and the other using the Traditional School Day (TSD) schedule. METHODS Participation of students between grades 3 and 6 was sought. Data were collected over 4 school days using pedometers. Independent Sample t tests and 1-way analysis of variance (ANOVA) were performed. RESUTLS A total of 117 students participated. Overall, average daily step counts for boys (6972 ± 1952) were significantly higher than girls (5742 ± 1495; p < .001). These average step counts represent 47% and 48% of the recommended amount of steps needed for health benefits for children between the ages of 6 and 12. The average daily step count for students using the BSD schedule was 6017 (±1666), while the average daily step count for students using the TSD schedule was 6788 (±1987). The difference in steps (771) was statistically significant (p = .03). CONCLUSIONS These results do not support claims that the BSD offers increased physical activity. In fact, these results suggest that students enrolled in schools using the BSD schedule may have reduced daily physical activity. In addition, these results demonstrate that overall school-based physical activity is less than half of the recommended level; independent of school scheduling.

Smoke Exposure Has Transient Pulmonary and Systemic Effects in Wildland Firefighters

Respiratory exposure to air pollutants is associated with cardiovascular morbidity and mortality and firefighters have been shown to be at an increased risk of work-related cardiovascular events. Wildland firefighters experience intermittent, intense exposure to biomass smoke. The aim of this study was to characterize the respiratory and systemic effects of smoke exposure in wildland firefighters. Seventeen seasonal firefighters from a northeastern Ontario community were recruited at the beginning of the fire season and baseline measurements obtained; postexposure measurements were made at various times within 16 d of firefighting. Spirometric measurements showed a transient decline in forced vital capacity within 7 d of fire exposure, not evident by 8–16 d. Induced sputum showed a significant increase in macrophages and epithelial cells within 7 d, with evidence that macrophages had internalized particles; such changes were not evident in the second week following exposure. Likewise, peripheral blood analysis revealed significant increases in erythrocytes, hemoglobin, monocytes, and platelets within the first week after fire exposure, which were diminished 8–16 d in postexposure group. We conclude that acute exposure to forest-fire smoke elicits transient inflammatory responses, both in the airways and systemically. Whether these changes contribute to the observed increased risk of cardiovascular events requires further study.

Photographic Examination of Student Lunches in Schools Using the Balanced School Day Versus Traditional School Day Schedules

Background. Canadian schools have broadly adopted a schedule where school days are divided into 3 blocks with 2 breaks. Given childhood obesity rates, changes affecting diet should be examined. The...

Alcohol fixation of induced sputum samples for applications in rural communities.

BACKGROUND Sputum induction is a tool recommended for the assessment of airway inflammation and disease management. Currently, its use is limited because samples need to be processed within 3 h of induction (ie, while cells are viable); therefore, this procedure is unavailable to most clinicians. OBJECTIVE To develop a fixation method for induced sputum samples that allows for a delay in processing while maintaining sample integrity and not altering the standard processing method. METHODS Sputum samples were collected and split into three portions: a fresh sample processed using the routine method (within 3 h, using dithiothreitol); fixation in alcohol followed by delayed processing using the routine method (within 48 h to 72 h, using dithiothreitol); and fixation in formaldehyde followed by delayed processing using an alternative method (within 48 h to 72 h, using proteolysis). For each method, cytospins were prepared and differential cell counts were performed. RESULTS Fixation in alcohol provides accurate measures of eosinophils and macrophages, but not neutrophils. Formaldehyde fixation provides accurate measures of neutrophils and macrophages, but not eosinophils. DISCUSSION Alcohol fixation is a superior method for eosinophil quantification. It requires alteration of standardized methods for sputum sample processing and should be recommended for monitoring eosinophilic airway disease in settings where immediate processing of a sputum sample is not possible.

Novel Tools in Determining the Physiological Demands and Nutritional Practices of Ontario FireRangers during Fire Deployments

Introduction The seasonal profession of wildland fire fighting in Canada requires individuals to work in harsh environmental conditions that are physically demanding. The purpose of this study was to use novel technologies to evaluate the physiological demands and nutritional practices of Canadian FireRangers during fire deployments. Methods Participants (n = 21) from a northern Ontario Fire Base volunteered for this study and data collection occurred during the 2014 fire season and included Initial Attack (IA), Project Fire (P), and Fire Base (B) deployments. Deployment-specific energy demands and physiological responses were measured using heart-rate variability (HRV) monitoring devices (Zephyr BioHarness3 units). Food consumption behaviour and nutrient quantity and quality were captured using audio-video food logs on iPod Touches and analyzed by NutriBase Pro 11 software. Results Insufficient kilocalories were consumed relative to expenditure for all deployment types. Average daily kilocalories consumed: IA: 3758 (80% consumption rate); P: 2945±888.8; B: 2433±570.8. Average daily kilocalorie expenditure: IA: 4538±106.3; P: 4012±1164.8; B: 2842±649.9. The Average Macronutrient Distribution Range (AMDR) for protein was acceptable: 22–25% (across deployment types). Whereas the AMDR for fat and carbohydrates were high: 40–50%; and low: 27–37% respectively, across deployment types. Conclusions This study is the first to use the described methodology to simultaneously evaluate energy expenditures and nutritional practices in an occupational setting. The results support the use of HRV monitoring and video-food capture, in occupational field settings, to assess job demands. FireRangers expended the most energy during IA, and the least during B deployments. These results indicate the need to develop strategies centered on maintaining physical fitness and improving food practices.

Expression profile of plakin cross-linking proteins in short-term denervated mouse hindlimb skeletal muscle

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