Health education and promotion of #PhysicalActivity on Twitter before and during COVID-19.

Objective: Twitter, a microblogging service, allows users to post short messages (tweets) and link posts through hashtags, creating online communities to enable dissemination of health education. The objective of this descriptive study was to examine Twitter's #PhysicalActivity health education and promotion efforts, including differences in response before (March 2019-February 2020) and during (March 2020-February 2021) the COVID-19 pandemic. Design setting and methods: A codebook was developed to conduct a quantitative content analysis of #PhysicalActivity tweets before and during the COVID-19 pandemic. Twitter's Advanced Search parameters included minimum 1 reply, 25 likes and 5 retweets. Tweets were double-coded for user characteristics, community response, tweet elements (video, photo, link, questions, events, original text, survey/response, journal article, infographic) and intended audience. T-tests examined differences in researcher-generated NET response (replies + retweets + likes) between COVID-19 and comparison years. Results: Data were collected from 400 tweets. Eighty percent of tweets were from personal accounts, with over half indicating the possession of a health professional degree. Twenty-nine percent of tweets gave behavioural recommendations of which 56.8% provided a rationale. Nearly all used at least two components, text and photos most common. The general public was the most intended audience with health professionals second. While the NET response was greater during COVID-19 (M = 139.6, SD = 156.8) than prior to it (M = 116.8, SD = 105.1), the difference was not statistically significant (p = .091). Conclusion: Twitter platform provided an opportunity to disseminate health education, specifically for the promotion of physical activity, while adhering to public health recommendations to #StaySafeStayHome. Our findings provide insights into engaging this online community to inform future physical education and promotion dissemination.

Physical activity moderates the association between school start time and sleep duration in a cross-sectional national sample of adolescents.

Background: Adolescent insufficient sleep is an endemic issue that may result in compromised functioning throughout the course of the day and is associated with increased risk for a variety of adverse outcomes. Early school start time (SST) has been consistently found to be detrimental to adolescents' sleep achievement on school nights. However, there are logistical barriers to changing SST. Evidence supports daily engagement in moderate-to-vigorous intensity physical activity (MVPA) to enhance adolescents' nightly sleep achievement. However, the role of MVPA in the association between SST and sleep duration is unknown. This study examines the potential moderating effect of MVPA in the association between SST and sleep duration on a typical school day among adolescents. Methods: This study examined data (collected in April and October 2014) from a national sample of 1132 adolescents (m age = 14.5 years) living in the United States from the Family Life, Activity, Sun, Health, and Eating study, a cross-sectional, internet-based survey. First, three linear regressions were computed to examine bivariate associations between SST, MVPA, and sleep duration while controlling for participant sex, race and ethnicity, household income, school level, and the presence of a TV in the bedroom. Next, a three-step multiple regression was computed with sleep duration as the dependent variable, and the final step included an interaction term between SST and MVPA. Results: Later SST (b 1 = 0.41, p < 0.001) and increased MVPA (b 1 = 0.39, p < 0.001) were both associated with increased sleep duration, while SST and MVPA were not significantly associated. In the final multiple regression model, which included the interaction term, school day MVPA moderated the positive association between SST and school night sleep duration (b 1 = - 3.7, p < 0.05), such that the greater the MVPA on a typical school day, the weaker the positive association between early SST and sleep duration. In post-hoc analysis, the interaction effect was only significant for females and not males. Conclusions: The significant buffering effect of MVPA on the association between SST and sleep duration suggests that in the absence of SST changes, promoting MVPA among adolescents may be a promising strategy to mitigate insufficient sleep among US adolescents.

Behavioral trade-offs and multitasking by elk in relation to predation risk from Mexican gray wolves.

Predator non-consumptive effects (NCE) can alter prey foraging time and habitat use, potentially reducing fitness. Prey can mitigate NCEs by increasing vigilance, chewing-vigilance synchronization, and spatiotemporal avoidance of predators. We quantified the relationship between Mexican wolf (Canis lupus baileyi) predation risk and elk (Cervus canadensis) behavior. We conducted behavioral observations on adult female elk and developed predation risk indices using GPS collar data from Mexican wolves, locations of elk killed by wolves, and landscape covariates. We compared a priori models to determine the best predictors of adult female behavior and multitasking. Metrics that quantified both spatial and temporal predation risk were the most predictive. Vigilance was positively associated with increased predation risk. The effect of predation risk on foraging and resting differed across diurnal periods. During midday when wolf activity was lower, the probability of foraging increased while resting decreased in high-risk areas. During crepuscular periods when elk and wolves were most active, increased predation risk was associated with increased vigilance and slight decreases in foraging. Our results suggest elk are temporally avoiding predation risk from Mexican wolves by trading resting for foraging, a trade-off often not evaluated in behavioral studies. Probability of multitasking depended on canopy openness and an interaction between maternal period and predation risk; multitasking decreased prior to parturition and increased post parturition in high-risk areas. Openness was inversely related to multitasking. These results suggest adult female elk are altering the type of vigilance used depending on resource availability/quality, current energetic needs, and predation risk. Our results highlight potentially important, but often-excluded behaviors and trade-offs prey species may use to reduce the indirect effects of predation and contribute additional context to our understanding of predator-prey dynamics.

American martens use vigilance and short-term avoidance to navigate a landscape of fear from fishers at artificial scavenging sites.

Where two sympatric species compete for the same resource and one species is dominant, there is potential for the subordinate species to be affected through interference competition or energetic costs of avoiding predation. Fishers (Pekania pennanti) and American martens (Martes americana) often have high niche overlap, but fishers are considered dominant and potentially limiting to martens. We observed presence and vigilance of fishers and martens at winter carcass sites using remote cameras in Michigan, USA, to test the hypothesis that interference competition from fishers creates a landscape of fear for martens. Within winters, fishers co-occupied 78-88% of sites occupied by martens, and martens co-occupied 79-88% of sites occupied by fishers. Fishers displaced martens from carcasses during 21 of 6117 marten visits, while martens displaced fishers during 0 of 1359 fisher visits. Martens did not alter diel activity in response to fisher use of sites. Martens allocated 37% of time to vigilance compared to 23% for fishers, and martens increased vigilance up to 8% at sites previously visited by fishers. Fishers increased vigilance by up to 8% at sites previously visited by martens. Our results indicate that fishers were dominant over martens, and martens had greater baseline perception of risk than fishers. However, fishers appeared to be also affected as the dominant competitor by putting effort into scanning for martens. Both species appeared widespread and common in our study area, but there was no evidence that fishers spatially or temporally excluded martens from scavenging at carcasses other than occasional short-term displacement when a fisher was present. Instead, martens appeared to mitigate risk from fishers by using vigilance and short-term avoidance. Multiple short-term anti-predator behaviors within a landscape of fear may facilitate coexistence among carnivore species.

Soft Tissue Impingement of the Ankle: Pathophysiology, Evaluation, and Arthroscopic Treatment.

Soft tissue impingement (STI) syndrome is one of 3 causes of a larger all-encompassing joint impingement pathologic condition, which also includes bone and neuropathic entrapment. Altered joint biomechanics and friction of joint tissues combine to cause chronic pain and often functional instability. Although the most common form of STI to the ankle is anterolateral in location, posterior and anteromedial impingement is also discussed in this article. Furthermore, a discussion of biomechanical deficiencies and how they may effect location and cause of STI of the ankle is explored along with pathophysiology, clinical and diagnostic evaluation, current treatments, and long-term outcomes.