Chest Tightness with Cycling Turned Out To Be Pneumomediastinum.

BACKGROUND Pneumomediastinum, or mediastinal emphysema, means air present inside the mediastinum. It usually presents with symptoms of chest pain and shortness of breath. Examination can be significant for crepitus along the neck area. There are many risk factors associated with pneumomediastinum, including asthma and COVID-19. Most cases of pneumomediastinum improve with conservative management, and surgery (mediastinotomy) is reserved for complicated cases with tension pneumomediastinum. CASE REPORT This is the case of a 23-year-old man who presented with chest tightness after 3.5 h of cycling. The patient did have a prior history of clinically stable asthma, with no recent exacerbation, and denied any other associative factors. Imaging was significant for pneumomediastinum. The patient was admitted for observation in the hospital and treated with supportive care, without any surgical intervention. The patient had appropriate improvement in his symptoms in 24 h. Repeat imaging showed improvement in the pneumomediastinum, and the patient was discharged to outpatient follow-up. CONCLUSIONS Our case presents a unique link between cycling and pneumomediastinum. Prolonged cycling may emerge as a risk factor for this complication. People with a previous history of pneumomediastinum should be careful to review other risk factors prior to planning long-distance bicycling. Physicians need to keep this differential diagnosis in mind when encountering a patient with similar symptoms so that a timely diagnosis is made.

The Impact of the COVID-19 Pandemic on Pediatric Bicycle Injury.

Bicycling is a common childhood activity that is associated with significant injury risk. This study's aim was to assess pediatric bicycle injury epidemiology and impacts of the COVID-19 pandemic. We conducted a cross-sectional evaluation of patients age < 18 years presenting with bicycle injury to a pediatric trauma center. A pre-pandemic period (1 March 2015-29 February 2020) was compared to the pandemic period (1 March 2020-28 February 2021). A total of 611 injury events for children < 18 years were included (471 pre-pandemic events and 140 pandemic events). The relative frequency of pandemic injuries was greater than pre-pandemic injuries (p < 0.001), resulting in a 48% increase in pandemic period injuries versus the pre-pandemic average (141 pandemic vs. 94.4/year pre-pandemic). Individuals of female sex represented a larger proportion of injuries in the pandemic period compared to the pre-pandemic period (37% pandemic vs. 28% pre-pandemic, p = 0.035). Injuries were more common on weekends versus weekdays (p = 0.01). Time series analysis showed a summer seasonality trend. Localizing injury events to ZIP codes showed regional injury density patterns. During COVID-19, there was an increase in bicycle injury frequency and proportional shift toward more injuries involving individuals of female sex. Otherwise, injury patterns were largely unchanged. These results demonstrate the necessity of safety interventions tailored to community needs.

When crisis hits: Bike-Sharing platforms amid the Covid-19 pandemic.

In this work, we examine the changes in demand for bike-sharing platforms with the onset of the Covid-19 pandemic. Using the fixed-effects regression formulation of difference-in-differences, we evaluate how the demand for bike-sharing platforms changed after the first cases of Covid were discovered and after the first executive orders were implemented. Accounting for weather conditions, socio-economic characteristics, time trends, and fixed effects across cities, our findings indicate that there is an increase in daily bike-sharing trips by 22% on average after the first Covid-19 case diagnosis, and a decrease of 30% after the first executive order implementation in each municipality, using the data up to August 2020. Moreover, we observe a 22% increase in weekday-specific trip frequency after the first Covid-19 case diagnosis and a 28% decrease in weekend-specific trip frequency after the first executive order implementation. Finally, we find that there is an increase in the frequency of trips on bike-sharing platforms in more bike-friendly, transit-friendly, and pedestrian-friendly cities upon both the first Covid-19 case diagnosis and the first executive order implementation.

[Dooring Bicycle Accidents with Severe Injury Patterns: 10-Year Study of a Level 1 Trauma Center]. / Dooring-Fahrradunfälle mit schweren Verletzungsmustern: 10-Jahres-Studie eines Level-1-Traumazentrums.

Dooring Bicycle Accidents with Severe Injury Patterns: 10-Year Study of a Level 1 Trauma Center Abstract. Studies in Switzerland, Germany and Austria have shown that, contrary to popular belief, dooring accidents are among the most common bicycle accidents. The resulting injuries are often serious and often lead to hospital admission. All dooring accidents of the Inselspital Emergency Department in Bern between 2012 and 2021 were identified and evaluated retrospectively. The data were generated from the database of the management system (Ecare) of the University Hospital Bern by means of a search query with the German keywords: "Autotüre", "Autotuere", "Dooring" and were anonymised. Most patients were female and on average 34 years old; most injuries occurred to the head and the extremities. Treatment was mostly done on an outpatient basis. The ISS (Injury Severity Score) was an average of 3.5. One of the patients needed emergency surgery. This is the first Swiss study to systematically record and evaluate dooring accidents. Since cycling is a trend, especially in urban areas, and consequently the number of cyclists is constantly increasing, it can be assumed that the number of dooring injuries will also increase and corresponding prevention measures will have to be taken. The current COVID-19 pandemic tends to aggravate the problem, as in the context of infection control the number of cyclists and, consequently, accidents is increasing, especially in urban areas, in the context of infection control. This said, it is crucial to gain more information about the time slots of the accidents and the casualties through appropriate studies in order to take adequate preventive and protective measures.

CYCLING AND PANDEMICS: relationships between the socioeconomic profile of cyclists in Goiânia/GO and actions during ride bike to prevent contagion by SARS-CoV-2 (COVID 19) / Ciclismo e pandemia: relações entre o perfil socioeconômico de ciclistas de Goiânia/GO e ações durante o pedal para prevenir o contágio pelo SARS-CoV-2 (COVID 19) / CICLISMO Y PANDEMIA: relaciones entre el perfil socioeconómico de ciclistas de Goiânia/GO y acciones durante el pedaleo para prevenir el contagio por el SARS-CoV-2 (COVID 19

Este estudo articulou relações entre o perfil de ciclistas de lazer e mudanças em seus hábitos de pedalar em função da pandemia provocada pelo SARS-CoV-2 (COVID 19). Os dados foram obtidos por formulário eletrônico e tratados em plataforma específica. O total de ciclistas respondentes foi de 87. Em perfil, obteve-se: idade, renda, nível de escolaridade e fontes de informação/notícias. Sobre como pedalam em função da pandemia, tivemos: pedala só ou em grupo e com ou sem máscara. Os resultados mostram que os ciclistas têm, predominantemente, idade acima de 30 anos, escolaridade universitária e renda acima de R$2.500. As mídias virtuais são a principal fonte de informação. A ação mais destacada para prevenir o contágio foi o uso de máscara; todavia, não houve relações significativas entre o perfil e novas formas de pedalar (AU).

This study articulated relationships between the profile of leisure cyclists and changes because of the pandemic caused by SARS-CoV-2 (COVID 19). Data were obtained by electronic form and processed in a specific platform. 87 was the total number of cyclists responding. In profile, obtained: age, monthly income, education level and sources of information/news; on the behavior in the practice of cycling we had pedal alone or in groups and with or without mask. The results show that cyclists are predominantly aged over 30 years old, have a university education and an income above R$2,500. Virtual media are the main source of information. The most prominent behavioral change was the use of a mask; however, there were no significant relationships between the profile and behavioral changes (AU).

Esta investigación articuló relaciones entre el perfil de ciclistas de ocio y cambios en la acción de pedalear en función de la pandemia por el SARS-CoV-2 (COVID 19). Los datos se obtuvieron por cuestionario electrónico, con 87 sujetos y tratados en plataforma específica. Los datos fueron: edad, niveles de renda y escolaridad y donde uno se informa; y sobre cambios se preguntó se pedalea solo o en grupo y si utiliza o no la máscara. Los resultados apuntan que la mayoría de los ciclistas tienen más de 30 años, nivel universitario y renda por arriba de R$2.500 e se informan por las medias virtuales. El principal cambio ha sido el uso de mascara. No se ha encontrado relaciones significativas entre el perfil y los cambios (AU).

Safer cycling in older age (SiFAr): effects of a multi-component cycle training. a randomized controlled trial.

BACKGROUND: The risk of older adults being injured or killed in a bicycle accident increases significantly due to the age-related decline of physical function. Therefore, targeted interventions for older adults to improve safe cycling competence (CC) are urgently needed. METHODS: The "Safer Cycling in Older Age" (SiFAr) randomized controlled trial investigated if a progressive multi-component training program related to cycling improves CC of older adults. Between June 2020 and May 2022, 127 community-dwelling persons living in the area Nürnberg-Fürth-Erlangen, Germany aged 65 years and older were recruited, who are either (1) beginners with the e-bike or (2) feeling self-reported unsteadiness when cycling or (3) uptaking cycling after a longer break. Participants were either randomized 1:1 to an intervention group (IG; cycling exercise program, 8 sessions within 3 months) or an active control group (aCG; health recommendations). The CC as primary outcome was tested not blinded in a standardized cycle course prior and after the intervention period and after 6-9 months, which consists of variant tasks requiring skills related to daily traffic situations. Regression analyses with difference of errors in the cycling course as dependent variable and group as independent variable adjusted for covariates (gender, number of errors at baseline, bicycle type, age and cycled distance) were performed. RESULTS: 96 participants (73.4 ± 5.1 years; 59.4% female) were analyzed for primary outcome. Compared to the aCG (n = 49), the IG (n = 47) made an average of 2.37 fewer errors in the cycle course after the 3 months intervention period (p = 0.004). People with more errors at baseline had higher potential for improvement (B=-0.38; p < 0.001). Women on average made 2.31 (p = 0.016) more errors than men, even after intervention. All other confounders had no significant effect on the difference in errors. The intervention effect was very stable until 6-9 months after the intervention (B=-3.07, p = 0.003), but decreased with a higher age at baseline in the adjusted model (B = 0.21, p = 0.0499). CONCLUSION: The SiFAr program increases cycling skills among older adults with self-perceived needs for improvement in CC and could easily be made available to a broad public due to its standardized structure and a train-the-trainer approach. TRIAL REGISTRATION: This study was registered with clinicaltrials.gov: NCT04362514 (27/04/2020), https://clinicaltrials.gov/ct2/show/NCT04362514 .

Practical approaches of PULSE Racing in training their athlete for the Cybathlon Global Edition Functional Electrical Stimulation bike race: a case report.

During the Cybathlon Global Edition 2020, athletes compete in a Functional Electrical Stimulation (FES) bike race. In this event, athletes with a spinal cord injury cover a distance of 1200 m on an adapted bike by using electrostimulation to activate their leg muscles in order to evoke a pedalling movement. This report reviews the training regimen, as designed by the PULSE Racing team, and the experience of one athlete in preparation for the Cybathlon Global Edition 2020. The training plan was designed to vary exercise modes in order to optimize physiological adaptations and minimize monotony for the athlete. Additional constraints due to coronavirus pandemic, e.g., postponement of the Cybathon Global Edition and modification from a live cycling track to a virtual stationary race, along with the health concerns of the athlete, e.g. unwanted effects from the FES and bladder infection, required creativity to ensure an effective and safe training protocol. The individual needs of the athlete and task requirements for the FES bike race made the design of a suitable training programme challenging, emphasizing the importance of monitoring. Several objective and subjective measures to assess the athlete's health and progress are presented, all with their own advantages and disadvantages. Despite these limitations, the athlete achieved a gold medal in the FES bike race Cybathlon Global Edition 2020 through discipline, team collaboration and the athlete's own motivation.

Estimating Mode of Transport in Daily Mobility during the COVID-19 Pandemic Using a Multinomial Logistic Regression Model.

At the beginning of 2020 there was a spinning point in the travel behavior of people around the world because of the pandemic and its consequences. This paper analyzes the specific behavior of travelers commuting to work or school during the COVID-19 pandemic based on a sample of 2000 respondents from two countries. We obtained data from an online survey, applying multinomial regression analysis. The results demonstrate the multinomial model with an accuracy of almost 70% that estimates the most used modes of transport (walking, public transport, car) based on independent variables. The respondents preferred the car as the most frequently used means of transport. However, commuters without car prefer public transport to walking. This prediction model could be a tool for planning and creating transport policy, especially in exceptional cases such as the limitation of public transport activities. Therefore, predicting travel behavior is essential for policymaking based on people's travel needs.

Factors associated with bicycle helmet use and proper fit: a cross-sectional survey of Montreal cyclists during the COVID-19 pandemic.

OBJECTIVES: With increased bicycle use during the COVID-19 pandemic and growing availability of bicycle-sharing programs in Montreal, we hypothesize helmet use has decreased. The aim of this study was to evaluate helmet use and proper fit among Montreal cyclists during the pandemic relative to historical data. METHODS: Nine observers collected data on bike type, gender, helmet use, and ethnicity using the iHelmet© app at 18 locations across the island of Montreal from June to September 2021. Proper helmet wear was assessed at one busy location. Multiple logistic regression was used to identify factors associated with helmet wear and results were compared to a historical study. RESULTS: Of the 2200 cyclists observed, 1109 (50.4%) wore a helmet. Males (OR = 0.78, 95%CI = 0.65-0.95), young adults (OR = 0.65, 95%CI = 0.51-0.84), visible minorities (OR = 0.38, 95%CI = 0.28-0.53), and bike-share users (OR = 0.21, 95%CI = 0.15-0.28) were less likely to be wearing a helmet, whereas children (OR = 3.92, 95%CI = 2.17-7.08) and cyclists using racing bicycles (OR = 3.84, 95%CI = 2.62-5.62) were more likely to be wearing a helmet. The majority (139/213; 65.3%) of assessed cyclists wore properly fitting helmets. Children had the lowest odds of having a properly fitted helmet (OR = 0.13, 95%CI = 0.04-0.41). Compared to 2011, helmet use during the pandemic increased significantly (1109/2200 (50.4%) vs. 2192/4789 (45.8%); p = 0.032). CONCLUSION: Helmet use among Montreal cyclists was associated with age, gender, ethnicity, and type of bicycle. Children were least likely to have a properly fitted helmet. The recent increase in popularity of cycling and expansion of bicycle-sharing programs reinforce the need for bicycle helmet awareness initiatives, legislation, and funding prioritization.

RéSUMé: OBJECTIF: Avec la popularité grandissante du vélo durant la pandémie COVID-19 et l'expansion du vélopartage à Montréal, nous croyons que le port du casque a diminué. L'objectif de cette étude était d'évaluer l'utilisation du casque et le port adéquat parmi les cyclistes montréalais et de comparer nos résultats avec des données historiques. MéTHODE: Neuf observateurs, stationnés à 18 emplacements, ont recueilli les informations suivantes en utilisant l'application mobile iHelmet© : type de vélo, sexe, origine ethnique et port du casque. Le port adéquat du casque a été observé à un endroit. L'association de chaque variable avec le port et le port adéquat a été fait par régression multivariable et comparé à des données historiques. RéSULTATS: Des 2 200 cyclistes observés, 1 109 (50,4 %) portaient un casque. Les enfants (OR = 3,92, IC95% = 2,17­7,08) et les cyclistes de performance (OR = 3,84, IC95% = 2,62­5,62) portaient le casque plus fréquemment tandis que les hommes (OR = 0,78, IC95% = 0,65­0,95), les jeunes adultes (OR = 0,65, IC95% = 0,51­0,84), les minorités visibles (OR = 0,38, IC95% = 0,28­0,53), et les utilisateurs de vélopartage (OR = 0,21, IC95% = 0,15­0,28) le portaient moins. La majorité (139/213; 65,3 %) des casques étaient portés adéquatement. Les enfants étaient plus à risque de porter un casque mal ajusté (OR = 0,13, IC95% = 0,04­0,41). L'utilisation d'un casque chez les cyclistes montréalais a augmenté significativement depuis 2011 (1 109/2 200 (50,4 %) c. 2 192/4 789 (45,8 %); p = 0,032). CONCLUSION: Le port du casque à vélo à Montréal est associé à l'âge, le sexe, l'origine ethnique et le type de vélo. Les enfants sont plus à risque de mal porter un casque. Des stratégies de promotion ainsi que la législation peuvent favoriser des comportements sécuritaires à vélo.

A data-driven approach to the "Everesting" cycling challenge.

The "Everesting" challenge is a cycling activity in which a cyclist repeats a hill until accumulating an elevation gain equal to the elevation of Mount Everest in a single ride. The challenge experienced a surge in interest during the COVID-19 pandemic and the cancelation of cycling races around the world that prompted cyclists to pursue alternative, individual activities. The time to complete the Everesting challenge depends on the fitness and talent of the cyclist, but also on the length and gradient of the hill, among other parameters. Hence, preparing an Everesting attempt requires understanding the relationship between the Everesting parameters and the time to complete the challenge. We use web-scraping to compile a database of publicly available Everesting attempts, and we quantify and rank the parameters that determine the time to complete the challenge. We also use unsupervised machine learning algorithms to segment cyclists into distinct groups according to their characteristics and performance. We conclude that the power per unit body mass of the cyclist and the tradeoff between the gradient of the hill and the distance are the most important considerations when attempting the Everesting challenge. As such, elite cyclists best select a hill with gradient > 12%, whereas amateur and recreational cyclists best select a hill with gradient < 10% to minimize the time to complete the Everesting challenge.

Intended cycling frequency and the role of happiness and environmental friendliness after COVID-19.

Although the COVID-19 pandemic has contributed to an increase in cycling in many countries worldwide, it is not yet known whether this increase becomes a long-lasting change in mobility. The current study explores this increase by analyzing data collected in a U.S. nationwide longitudinal survey. Using a total of 7421 observations, a mixed logit model with heterogeneity in the means of random parameters was estimated. In the resulting sample, nearly 14 percent of the respondents stated that they were planning to cycle more while only 4 percent of the respondents stated that they were planning to cycle less post COVID-19 pandemic. The estimation results provide insights into socio-demographic and psychological factors that play a role in planned cycling behavior post COVID-19. The study also establishes that age, race, employment status, gender, and household size impact intended cycling frequency. The model estimation results further indicate that workers (full time and part time), individuals with a high degree of life satisfaction, and individuals who are environmentally friendly all have higher cycling-frequency probabilities relative to others. The findings can be used to support policies that target sustainable mobility and further our understanding of the transportation, psychology, and well-being relationships.

National incidence and trends of bicycle injury.

Bicycle utilization continues to increase annually, and this trend was recently accelerated by the coronavirus disease of 2019 pandemic. There is limited epidemiologic data, however, regarding the prevalence and nature of bicycle-related injuries. Therefore, the purpose of this study is to characterize trends in bicycle-related injuries. The National Electronic Injury Surveillance System was queried for bicycle-related injuries from 2012 to 2021. Patient demographic and injury data were collected and analyzed to describe trends in incidence, patient demographics, and injury patterns associated with an emergency department encounter for a bicycle-related injury. There were an estimated 4,666,491 (95% confidence interval: 4,661,472-4,671,510) bicycle-related injuries from 2012 to 2021. The incidence of these injuries has significantly decreased over time (R = -0.983, R2 = 0.967, p < 0.001). However, the rate of injury in elderly patients increased over time. Injuries occurred most often during summer months (36%) and on weekend days (31.9%). Males and younger patients were more commonly injured. Head injuries were the most commonly affected body part among all age groups. Fractures were the most common injury type overall. Upper extremity injuries were more common than the lower extremity. Despite increased public bicycle utilization, there is a significant downtrend in bicycle-related injuries over the last decade. Injuries among elderly patients are becoming more common, who demonstrate a high rate of fracture and head injury. Fractures and head injuries were the most common injuries among all age groups, highlighting the importance of bicycle safety initiatives and helmet-wearing regardless of age.

The Canadian Bikeway Comfort and Safety metrics (Can-BICS): National measures of the bicycling environment for use in research and policy.

Background: The lack of consistent measures of the cycling environment across communities hampers cycling research and policy action. Our goal was to develop the first national dataset in Canada for metrics of the cycling environment at the dissemination area (DA) level - the Canadian Bikeway Comfort and Safety (Can-BICS) metrics. Data and methods: The Can-BICS metrics are area-level metrics based on the quantity of cycling infrastructure within a 1 km buffer of the population-weighted centroid of DAs. The base data are a national cycling network dataset derived from OpenStreetMap (OSM) (extracted January 25, 2022) and classified by high-, medium- and low-comfort facilities. A Can-BICS continuous metric (sum of cycling infrastructure per square kilometre weighted by comfort class) and Can-BICS categorical metric were derived and mapped for all 56,589 DAs in Canada. The Can-BICS metrics were correlated with other national datasets (2016 Canadian Active Living Environments [Can-ALE] and 2016 Census journey-to-work data) to test for associations between Can-BICS and related measures. Additionally, city staff were engaged to provide feedback on metrics during the development phase. Results: One-third (34%) of neighbourhoods in Canada have no cycling infrastructure. According to the categorical measure, 5% of all DAs were assigned as the highest category of Can-BICS (corresponding to 6% of the population) and were nearly all within metro areas. The Can-BICS continuous metric had low correlation with bike-to-work rates (R = 0.29) and was more strongly correlated with sustainable-transportation-to-work rates (R = 0.56) and the Can-ALE metrics (R=0.62). These correlations were variable across cities. Interpretation: The Can-BICS metrics provide national research- and practice-ready measures of cycling infrastructure. The metrics complement existing measures of walking and transit environments (Can-ALE), collectively providing a cohesive set of active living measures. The datasets and code are publicly available, facilitating updates as new infrastructure is built.

Risky business: Comparing the riding behaviours of food delivery and private bicycle riders.

The growth in the gig economy and a preference for home delivery of meals due to COVID-19 have led to huge growth in the food delivery business internationally and consequent road safety concerns. There is increasing evidence that delivery riding is an occupation with significant road safety risks because work pressures encourage risky behaviours. However, there is little or no research that directly compares delivery and private riders. Thus, the aim of this study was to examine the impact of riding for work by comparing the observable riding behaviours of food delivery and private bicycle riders. Specifically, this investigation used decision trees to analyse the prevalence and patterns of risky riding behaviours of 2274 bicycle food delivery riders (BFDRs) and 1127 private bicycle riders observed in the inner suburbs of Brisbane, Australia. The results showed that helmet use was higher for BFDRs than private riders (99.8% versus 93.4%) but varied by company and for some companies, female BFDRs had lower wearing rates. Male BFDRs on electric bikes were more likely to wear helmets than those on standard bikes (99.7% versus 94.9%). Using a handheld mobile phone or having a mobile phone in a cradle was less common for one company (0.6%) than for the others (3.0%) or among private riders (1.8%). Among riders from the Other Companies, using a handheld mobile phone was more common on standard bikes and differed by time of day. Female BFDRs were more likely to be observed using handheld mobile phones. Overall, 24.0% of riders facing a red traffic or pedestrian signal ("red light") did not stop. This was more common among riders who rode on the footpath (Australian term for sidewalk), and particularly those who moved between the footpath and the road on electric bikes (49.5%) and among those who rode in the wrong direction in the traffic lane (55.0%). Whether the rider was a BFDR or private rider had little influence on red light running. The results suggest that BFDRs are not more likely to perform the risky behaviours examined, but that other factors such as bicycle type, gender, time of day and infrastructure appear to be more important determinants. However, the differences among companies suggest that organisational factors deserve further investigation.

Everesting: cycling the elevation of the tallest mountain on Earth.

PURPOSE: With few cycling races on the calendar in 2020 due to COVID-19, Everesting became a popular challenge: you select one hill and cycle up and down it until you reach the accumulated elevation of Mt. Everest (8,848 m or 29,029ft). With an almost infinite number of different hills across the world, the question arises what the optimal hill for Everesting would be. Here, we address the biomechanics and energetics of up- and downhill cycling to determine the characteristics of this optimal hill. METHODS: During uphill cycling, the mechanical power output equals the power necessary to overcome air resistance, rolling resistance, and work against gravity, and for a fast Everesting time, one should maximize this latter term. To determine the optimal section length (i.e., number of repetitions), we applied the critical power concept and assumed that the U-turn associated with an additional repetition comes with a 6 s time penalty. RESULTS: To use most mechanical power to overcoming gravity, slopes of at least 12% are most suitable, especially since gross efficiency seems only minimally diminished on steeper slopes. Next, we found 24 repetitions to be optimal, yet this number slightly depends on the assumptions made. Finally, we discuss other factors (fueling, altitude, fatigue) not incorporated in the model but also affecting Everesting performances. CONCLUSION: For a fast Everesting time, our model suggests to select a hill climb which preferably starts at (or close to) sea level, with a slope of 12-20% and length of 2-3 km.

A Demand-Centric Repositioning Strategy for Bike-Sharing Systems.

Transport-sharing systems are eco-friendly and the most promising services in smart urban environments, where the booming Internet of things (IoT) technologies play an important role in the smart infrastructure. Due to the imbalanced bike distribution, bikes and stalls in the docking stations could be unavailable when needed, leading to bad customer experiences. We develop a dynamic repositioning strategy for the management of bikes in this paper, which supports dispatchers to keep stations in service. Two open datasets are examined, and the exploratory data analysis presents that there is a significant difference of travel patterns between working and non-working days, where the former has an excess demand at rush hours and the latter is usually at a low demand. To evaluate the effect when the demand outstrips a station's capacity, we propose a non-linear scaling technique to transform demand patterns and perform the clustering analysis for each of five categories obtained from the sophisticated analysis of the dataset. Our repositioning strategy is developed according to the transformed demands. Compared with the previous work, numerical simulations reveal that our strategy has a better performance for high-demand stations, and thus can substantially reduce the repositioning cost, which brings benefit to bike-sharing operators for managing the city bike system.

Impacts of the COVID-19 pandemic on the spatio-temporal characteristics of a bicycle-sharing system: A case study of Pun Pun, Bangkok, Thailand.

The COVID-19 pandemic is found to be one of the external stimuli that greatly affects mobility of people, leading to a shift of transportation modes towards private individual ones. To properly explain the change in people's transport behavior, especially in pre- and post- pandemic periods, a tensor-based framework is herein proposed and applied to Pun Pun-the only public bicycle-sharing system in Bangkok, Thailand-where multidimensional trip data of Pun Pun are decomposed into four different modes related to their spatial and temporal dimensions by a non-negative Tucker decomposition approach. According to our computational results, the first pandemic wave has a sizable influence not only on Pun Pun but also on other modes of transportation. Nonetheless, Pun Pun is relatively more resilient, as it recovers more quickly than other public transportation modes. In terms of trip patterns, we find that, prior to the pandemic, trips made during weekdays are dominated by business trips with two peak periods (morning and evening peaks), while those made during weekends are more related to leisure activities as they involve stations nearby a public park. However, after the first pandemic wave ends, the patterns of weekday trips have been drastically changed, as the number of business trips sharply drops, while that of educational trips connecting metro/subway stations with a major educational institute in the region significantly rises. These findings may be regarded as a reflection of the ever-changing transport behavior of people seeking a sustainable mode of private transport, with a more positive outlook on the use of bicycle-sharing system in Bangkok, Thailand.

Effects of air pollution exposure on inflammatory and endurance performance in recreationally trained cyclists adapted to traffic-related air pollution.

The aim of the present study was to analyze the effects of traffic-related air pollution (TRAP) on markers of inflammatory, neuroplasticity, and endurance performance-related parameters in recreationally trained cyclists who were adapted to TRAP during a 50-km cycling time trial (50-km cycling TT). Ten male cyclists performed a 50-km cycling TT inside an environmental chamber located in downtown Sao Paulo (Brazil), under TRAP or filtered air conditions. Blood samples were obtained before and after the 50-km cycling TT to measure markers of inflammatory [interleukin-6 (IL-6), C-reactive protein (CRP), interleukin-10 (IL-10), intercellular adhesion molecule-1 (ICAM-1)] and neuroplasticity [brain-derived neurotrophic factor (BDNF)]. Rating of perceived exertion (RPE), heart rate (HR), and power output (PO) were measured throughout the 50-km cycling TT. There were no significant differences between experimental conditions for responses of IL-6, CRP, and IL-10 (P > 0.05). When compared with exercise-induced changes in filtered air condition, TRAP provoked greater exercise-induced increase in BDNF levels (TRAP = 3.3 ± 2.4-fold change; Filtered = 1.3 ± 0.5-fold change; P = 0.04) and lower exercise-induced increase in ICAM-1 (Filtered = 1.1 ± 0.1-fold change; TRAP = 1.0 ± 0.1-fold change; P = 0.01). The endurance performance-related parameters (RPE, HR, PO, and time to complete the 50-km cycling TT) were not different between TRAP and filtered air conditions (P > 0.05). These findings suggest that the potential negative impacts of exposure to pollution on inflammatory, neuroplasticity, and performance-related parameters do not occur in recreationally trained cyclists who are adapted to TRAP.

Cardiac cycle: an observational/interventional study protocol to characterise cardiopulmonary function and evaluate a home-based cycling program in children and adolescents born extremely preterm.

INTRODUCTION: Extremely preterm (EP)/extremely low birthweight (ELBW) individuals may have an increased risk for adverse cardiovascular outcomes. Compared with term-born controls, these individuals have poorer lung function and reduced exercise capacity. Exercise interventions play an important role in reducing cardiopulmonary risk, however their use in EP/ELBW cohorts is unknown. This study, cardiac cycle, aims to characterise the cardiopulmonary system of children and adolescents who were born EP compared with those born at term, following acute and chronic exercise bouts. METHODS AND ANALYSIS: The single-centre study comprises a home-based exercise intervention, with physiological characterisation at baseline and after completion of the intervention. Fifty-eight children and adolescents aged 10-18 years who were born EP and/or with ELBW will be recruited. Cardiopulmonary function assessed via measures of blood pressure, arterial stiffness, capillary density, peak oxygen consumption, lung clearance indexes and ventricular structure/function, will be compared with 58 age-matched and sex-matched term-born controls at baseline and post intervention. The intervention will consist of a 10-week stationary cycling programme, utilising Zwift technology. ETHICS AND DISSEMINATION: The study is approved by the Ethics Committee of the Royal Children's Hospital Melbourne under HREC2019.053. Results will be disseminated via peer-reviewed journal regardless of outcome. TRIAL REGISTRATION NUMBER: 12619000539134, ANZCTR.

Effects of Face Masks on Physiological Parameters and Voice Production during Cycling Activity.

This study investigates the effects of face masks on physiological and voice parameters, focusing on cyclists that perform incremental sports activity. Three healthy male subjects were monitored in a climatic chamber wearing three types of masks with different acoustic properties, breathing resistance, and air filtration performance. Masks A and B were surgical masks made of hydrophobic fabric and three layers of non-woven fabric of 100% polypropylene, respectively. Mask S was a multilayer cloth mask designed for sports activity. Mask B and Mask S behave similarly and show lower sound attenuation and sound transmission loss and lower breathing resistance than Mask A, although Mask A exhibits slightly higher filtration efficiency. Similar cheek temperatures were observed for Masks A and B, while a significantly higher temperature was measured with Mask S at incremental physical activity. No differences were found between the masks and the no-mask condition for voice monitoring. Overall, Mask B and Mask S are suitable for sports activities without adverse effects on voice production while ensuring good breathing resistance and filtration efficiency. These outcomes support choosing appropriate masks for sports activities, showing the best trade-off between breathing resistance and filtration efficiency, sound attenuation, and sound transmission loss.