Association of Changes in Missouri Firearm Laws With Adolescent and Young Adult Suicides by Firearms.

Importance: Suicide by firearm is a major cause of mortality in young Missouri residents. Changes in statewide firearm policy may have contributed to changes in suicide rates. Objective: To evaluate if changes in Missouri permit-to-purchase (PTP) and concealed carry firearm laws were associated with changes in rates of suicide by firearms in young Missouri residents. Design, Settings, and Participants: This cross-sectional study examined rates of suicide by firearm in Missouri among adolescents (ages 14-18 years) and young adults (ages 19-24 years) from January 1999 to December 2018, following changes to state PTP and concealed carry law, in comparison with a donor state pool with existing firearm laws (13 states in PTP pool; 42 states in concealed carry pool) that did not make changes during this period. This study used a quasiexperimental, synthetic control design at the state level that defined Missouri as the treated state and treatment as changes in firearm laws. Exposures: Legislative changes to Missouri's PTP and concealed carry firearm laws. Main Outcomes and Measures: Age-adjusted annual rates of firearm-related suicide mortality per 100 000 people for adolescents (aged 14-18 years) and young adults (aged 19-24 years). Results: Repeal of the PTP law was associated with a 21.8% increase in firearm suicide rates in young adults aged 19 to 24 years in Missouri. Lowering the minimum age of concealed carry to 19 years in Missouri was associated with a 32.0% increase in firearm suicide rates and a 29.7% increase in nonfirearm suicide rates in adolescents aged 14 to 18 years, and a 7.2% increase in firearm suicide rates in young adults aged 19 to 24 years. Conclusions and Relevance: Increases in rates of suicide by firearms in adolescents and young adults were seen following repeal of Missouri's PTP law and lowering of the minimum age for concealed carry in 2014. Changes in Missouri's firearm policies may be an important contributor to rates of suicide by firearm in young Missouri residents.

A Retrospective Analysis of Collegiate Athlete Blood Biomarkers at Moderate Altitude.

Morris, KL, Widstrom, L, Goodrich, J, Poddar, S, Rueda, M, Holliday, M, San Millian, I, and Byrnes, WC. A retrospective analysis of collegiate athlete blood biomarkers at moderate altitude. J Strength Cond Res 33(11): 2913-2919, 2019-Blood biomarkers are used to assess overall health and determine positive/negative adaptations to training/environmental stimuli. This study aimed to describe the changes in blood biomarkers in collegiate football (FB) (n = 31) and cross-country (XC) (n = 29; 16 women [FXC], 13 men [MXC]) athletes across a competitive season while training and living at a moderate altitude (1,655 m). This study used a database of previously collected hematological (complete blood count and serum ferritin) and muscle damage (lactate dehydrogenase and creatine kinase) blood biomarkers. Data were analyzed both within and between groups using linear mixed-model and variance component analyses, alpha = 0.05. All 3 groups had significant but different patterns of change in the measured biomarkers. Hematological blood biomarkers increased at different time points but remained within the normal reference ranges with greater between-subject vs. within-subject variability, suggesting no significant decrements to oxygen-carrying capacity across the season for FB, MXC, or FXC. Muscle damage biomarkers increased over time and exceeded the normal reference ranges, indicating cell damage pathology. However, it is also possible that the demands of training and competition might alter baseline values in these athletes, although this cannot be confirmed with the current experimental design. The patterns of change in the hematological and muscle damage biomarkers varied by sport discipline, suggesting that the training/competitive environments of these athletes influence these changes. Further studies should assess how much training, altitude, and nutrition influence these changes by using a more comprehensive set of biomarkers and related performance parameters.

Cardiometabolic Effects of a Workplace Cycling Intervention.

BACKGROUND: In laboratory settings, cycling workstations improve cardiometabolic risk factors. Our purpose was to quantify risk factors following a cycling intervention in the workplace. METHODS: Twenty-one office workers who sat at work ≥6 hours per day underwent baseline physiological measurements (resting blood pressure, blood lipid profile, maximum oxygen consumption [V˙O2max], body composition, and 2-h oral glucose tolerance test). Participants were randomly assigned to a 4-week intervention only group (n = 12) or a delayed intervention group (n = 9) that involved a 4-week control condition before beginning the intervention. During the intervention, participants were instructed to use the cycling device a minimum of 15 minutes per hour, which would result in a total use of ≥2 hours per day during the workday. Following the intervention, physiological measurements were repeated. RESULTS: Participants averaged 1.77 (0.48) hours per day of cycling during the intervention with no changes in actigraphy-monitored noncycling physical activity. Four weeks of the workplace intervention increased V˙O2max (2.07 [0.44] to 2.17 [0.44] L·min-1, P < .01); end of V˙O2max test power output (166.3 [42.2] to 176.6 [46.1] W, P < .01); and high-density lipoprotein cholesterol (1.09 [0.17] to 1.17 [0.24] mmol·L-1, P = .04). CONCLUSIONS: A stationary cycling device incorporated into a sedentary workplace for 4 weeks improves some cardiometabolic risk factors with no compensatory decrease in noncycling physical activity.

Pedelecs as a physically active transportation mode.

INTRODUCTION: Pedelecs are bicycles that provide electric assistance only when a rider is pedaling and have become increasingly popular. PURPOSE: Our purpose was to quantify usage patterns over 4 weeks of real-world commuting with a pedelec and to determine if pedelec use would improve cardiometabolic risk factors. METHODS: Twenty sedentary commuters visited the laboratory for baseline physiological measurements [body composition, maximum oxygen consumption ([Formula: see text]), mean arterial blood pressure (MAP), blood lipid profile, and 2-h oral glucose tolerance test (OGTT)]. The following 4 weeks, participants were instructed to commute using a pedelec at least 3 days week(-1) for 40 min day(-1) while wearing a heart rate monitor and a GPS device. Metabolic equivalents (METS) were estimated from heart rate data. Following the intervention, we repeated the physiological measurements. RESULTS: Average total distance and time were 317.9 ± 113.8 km and 15.9 ± 3.4 h, respectively. Participants averaged 4.9 ± 1.2 METS when riding. Four weeks of pedelec commuting significantly improved 2-h post-OGTT glucose (5.53 ± 1.18-5.03 ± 0.91 mmol L(-1), p < 0.05), [Formula: see text] (2.21 ± 0.48-2.39 ± 0.52 L min(-1), p < 0.05), and end of [Formula: see text] test power output (165.1 ± 37.1-189.3 ± 38.2 W, p < 0.05). There were trends for improvements in MAP (84.6 ± 10.5-83.2 ± 9.4 mmHg, p = 0.15) and fat mass (28.6 ± 11.3-28.2 ± 11.4 kg, p = 0.07). CONCLUSION: Participants rode a pedelec in the real world at a self-selected moderate intensity, which helped them meet physical activity recommendations. Pedelec commuting also resulted in significant improvements in 2-h post-OGTT glucose, [Formula: see text], and power output. Pedelecs are an effective form of active transportation that can improve some cardiometabolic risk factors within only 4 weeks.