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Caffeine improves short-to-moderate distance running performance, but the effect of caffeine on repeated sprints are equivocal. This research determined if caffeine improved exercise tolerance during repeated-sprint exercise. iCV is a running velocity that distinguishes intermittent running velocities (velocities ≤ iCV) that are sustainable from those resulting in a predictable time to exhaustion (velocities > iCV). Seven physically active men (age = 21.6 ± 1.5 years, body mass = 72.8 ± 5.1 kg, VO(2max) = 56.9 ± 9.8 mL/kg/min) ingested caffeine (5 mg/kg) or placebo (crossover design) 60 min prior to an intermittent critical velocity (iCV) test. The treadmill grade and velocity at VO(2max) (vVO(2max)) were used for iCV testing, and consisted of 3 bouts (10 sec running and 10 sec passive rest) at 130, 110 and 120% vVO(2max). Each bout continued until volitional exhaustion and was separated by 20 min of passive rest. Total distance and duration were recorded to determine exercise tolerance using the iCV model. Caffeine ingestion increased running duration at 110% vVO(2max) (p = 0.02), but not at 120 (p = 0.93) and 130% vVO(2max) (p = 0.14). Caffeine did not improve iCV model parameters. A single dose of caffeine consumed 60 min before repeated-sprints can improve performance at 110% vVO(2max), but not at higher velocities.

The study purpose was to determine the relationship of resting heart rate variability (HRV) and testosterone to cortisol (T:C) ratio, along with the diagnostic ability of HRV to assess changes in T:C ratio during a 9-week high-intensity functional training intervention. Eight recreationally-active men (n = 4, age 24.25 ± 1.75 yrs, height 181.25 ± 3.86 cm, weight 79.68 ± 11.66 kg) and women (n = 4, age 26 ± 3.6 yrs, height 164.25 ± 3.3, weight 73.4 ± 8.42) completed daily HRV measurements (HRVdaily) using photoplethysmography via a commercially-available smartphone application along with weekly saliva samples. Saliva samples were analyzed for concentrations of testosterone (T) and cortisol (C) via enzyme-linked immunosorbent assays. Upon study completion 72 data points were available, due to participant compliance and inadequate saliva sample, 67 matched pairs of HRV and T:C ratio were analyzed. A statistically significant negative relationship (n = 67, r = −.315, p < 0.05) was found between HRVdaily and saliva T:C ratio concentrations within aggregate data. Individual participant relationships showed considerable variability (r = −0.101 – 0.665, p = 0.103 to 0.829 The model which best explained the data resulted in AIC = 130.247 with factors HRVdaily (β = −0.218, 95%CI = −0.391, −0.044, t = −2.46, p < 0.05), Sex (β = 0.450, 95%CI = −0.214, 1.114, t = 1.113, p = 0.242), and Group (β = −0.394, 95%CI = −1.089, 0.302, t = −1.11, p = 0.311). Diagnostically, HRVdaily demonstrates excellent sensitivity (95%), but poor specificity (5%) for detecting meaningful changes in T:C ratio. Assessment of HRVdaily may be a clinically valid proxy measure for monitoring hormonal changes throughout a training intervention.

Introduction. A career in law enforcement is physically and mentally demanding, contributing to increased health risks and occupational stress. Physical activity and healthy eating are beneficial for maintaining a healthy weight and preventing many chronic health conditions (e.g. heart disease, cancer). While most police students must pass a fitness exam to enter training and again before becoming sworn police officers, it is unclear whether academy training prepares officers to develop healthy dietary habits for their careers. This study aimed to investigate typical dietary habits of police students at the University of Criminal Investigation and Police Studies, Belgrade, Serbia, and determine ways to improve officer education in healthy eating. Methods. A sample of police students (n = 137, 36.5% female) of average age 20.2 years participated in a survey to evaluate their typical dietary habits. Descriptive statistics were used to describe their nutritional behaviors. Results. Overall, the results suggest that most students make good nutrition decisions. The majority (78.1%) of students reported using alcohol responsibly, and 74.45% drank water between meals, though only 6.6% of students ate enough fruit every day. Almost all (98.5%) understood the importance of diet, but only 11.7% received nutrition-related information from a school source. Conclusion. Results suggest that police student training should include nutritional education and physical preparation for holistic police officer development. This approach could help prevent poor health outcomes for police officers.

Introduction Trails are associated with increased physical activity; however, little is known about the process of building trails by various types of organizations. From 2005 through 2012 the Sunflower Foundation: Health Care for Kansans (Sunflower) funded multiple organizations to construct 70 trails of varying lengths and surfaces in municipalities, schools, and communities across Kansas. The purpose of this study was to assess the process of developing and implementing community trail projects across Kansas with funding from a public foundation. Methods In 2012, we stratified funded organizations by type and conducted proportional random sampling to select 20 key informants from those organizations to participate in structured telephone interviews. Interviews were recorded and transcribed verbatim. Two researchers coded interview transcripts according to issues identified by participants. Results Issues associated with trail-building identified as important were collaboration among groups, unexpected construction costs, champions for the project, and level of difficulty of construction. Participants indicated that trails facilitated physical activity. Trails were integrated into communities through events such as walking events and other promotional efforts; these efforts were thought to increase trail use. The perceived outcomes of building the trails included providing the community with a physical activity resource, inspiring the community to start additional trail projects, and increasing the physical activity of local residents. Conclusion Sunflower’s funding was instrumental in developing trail projects to provide new physical activity resources across Kansas. Public health practitioners seeking to increase physical activity should seek funding from foundations that focus on health.

Background Features of the built environment that influence physical activity behavior characterize Active Community Environments. Context Whether Active Community Environments policies exist in the state of Hawaii's four counties is unknown. The purpose of this study was to provide a baseline assessment of these policies in Hawaii. Methods A survey assessing policies in six domains (i.e., sidewalks, bike lanes, greenways, recreational facilities, commercial buildings, and shared-use paths) was completed by employees of Hawaii planning departments. Consequences Honolulu County had the most policies (n = 13), followed by Maui County (n = 6), Kauai County (n = 2), and Hawaii County (n = 1). Written policies were most prevalent in Honolulu County (n = 15), followed by Kauai County (n = 14), Hawaii County, (n = 4), and Maui County (n = 3). Sidewalk policies were reported for Honolulu County, Maui County (no written policies were found for Maui County), and Kauai County. Bike lane and greenway policies were found for Honolulu County (reported and written) and Kauai County (written). Recreation facility and pedestrian shared-use path policies existed for all counties, although only Honolulu and Kauai counties had written policies for commercial buildings (Maui County reported having policies). Few policies directly addressed physical activity promotion. Interpretation The most populous county, Honolulu, had the most policies in place, although discrepancies existed between reported and written policies. This baseline measure of physical activity–related policies will help focus efforts of county coalitions to increase opportunities for physical activity. Additional policies should be tracked with population behavior surveillance.