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1.
Accid Anal Prev ; 163: 106449, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34749268

RESUMO

One of the most critical situations in urban areas is when motorists turn right in an intersection and cyclists cross the road. Many of those crashes result in severe consequences for cyclists. In order to increase the safety of cyclists, especially in the case of conflicts with right-turning vehicles, an online infrastructure-based assistance system may be a promising solution warning drivers and cyclists when a conflict or crash is predicted. By means of automated video traffic detection, the resulting trajectories of road users can be analysed and a warning can be sent to vehicles and cyclists equipped with vehicle-to-anything communication (V2X) when a high risk is estimated. An approach for online risk estimation was developed combining the surrogate measure of safety (SMoS) gap time (GT) with trajectory prediction-based estimates of the time-to-arrival (TTA) or distance to conflict point (DCp) and velocity (v). A decision tree as classifier of risk levels based on the previous named risk features was trained to model the risks perceived by humans. Expert ratings of traffic conflict scenes were used to build a model, apply the model, and improve it in the field. The warning system was evaluated by test drives in real traffic at the urban AIM Research Intersection in Braunschweig, Germany. In general, the system warned reliably. In approximately 67% of the trials, it was assessed as helpful.


Assuntos
Acidentes de Trânsito , Ciclismo , Acidentes de Trânsito/prevenção & controle , Árvores de Decisões , Alemanha , Humanos , Fatores de Risco , Segurança
2.
Artigo em Inglês | MEDLINE | ID: mdl-34769650

RESUMO

Accidents involving electric bicycles, a popular means of transportation in China during peak traffic periods, have increased. However, studies have seldom attempted to detect the unique crash consequences during this period. This study aims to explore the factors influencing injury severity in electric bicyclists during peak traffic periods and provide recommendations to help devise specific management strategies. The random-parameters logit or mixed logit model is used to identify the relationship between different factors and injury severity. The injury severity is divided into four categories. The analysis uses automobile and electric bicycle crash data of Xi'an, China, between 2014 and 2019. During the peak traffic periods, the impact of low visibility significantly varies with factors such as areas with traffic control or without streetlights. Furthermore, compared with traveling in a straight line, three different turnings before the crash reduce the likelihood of severe injuries. Roadside protection trees are the most crucial measure guaranteeing riders' safety during peak traffic periods. This study reveals the direction, magnitude, and randomness of factors that contribute to electric bicycle crashes. The results can help safety authorities devise targeted transportation safety management and planning strategies for peak traffic periods.


Assuntos
Traumatismos por Eletricidade , Ferimentos e Lesões , Acidentes de Trânsito , Automóveis , Ciclismo , Humanos , Modelos Logísticos
3.
Artigo em Inglês | MEDLINE | ID: mdl-34769699

RESUMO

The aims of this study were to describe patterns of active commuting to school (ACS) of preschool children, and to analyse the relationship between ACS and family socio-economic factors. A total of 2636 families of preschoolers (3-to-5 years old) were asked to complete a questionnaire at home about the mode of commuting to school of their children and marital status, educational level, and profession of both father and mother. Chi-square analyses were applied to compare ACS between school grades and gender of the children. To analyse the association of ACS with socio-economic factors, logistic regression analyses were performed. Almost 50% of participants reported ACS of their offspring, with a higher rate in 3rd preprimary grade (5 years old) than in 1st and 2nd preprimary grades (3- and 4-years old. All, p < 0.05). Those preschool children who had parents with lower educational level and no managerial work had higher odds to ACS than those who had parents with higher educational level and managerial work (all, p ≤ 0.001). Around half of the Spanish preschool children included in this study commuted actively to school and families with lower educational levels or worse employment situation were related to active commuting to school.


Assuntos
Fatores Econômicos , Caminhada , Ciclismo , Pré-Escolar , Estudos Transversais , Humanos , Instituições Acadêmicas , Fatores Socioeconômicos , Inquéritos e Questionários , Transportes
4.
Sensors (Basel) ; 21(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34640864

RESUMO

The traffic accident occurrence rate is increasing relative to the increase in the number of people using personal mobility device (PM). This paper proposes an airbag system with a more efficient algorithm to decide the deployment of a wearable bike airbag in case of an accident. The existing wearable airbags are operated by judging the accident situations using the thresholds of sensors. However, in this case, the judgment accuracy can drop against various motions. This study used the long short-term memory (LSTM) model using the sensor values of the inertial measurement unit (IMU) as input values to judge accident occurrences, which obtains data in real time from the three acceleration-axis and three angular velocity-axis sensors on the driver motion states and judges whether or not an accident has occurred using the obtained data. The existing neural network (NN) or convolutional neural network (CNN) model judges only the input data. This study confirmed that this model has a higher judgment accuracy than the existing NN or CNN by giving strong points even in "past information" through LSTM by regarding the driver motion as time-series data.


Assuntos
Air Bags , Dispositivos Eletrônicos Vestíveis , Acidentes de Trânsito , Ciclismo , Humanos , Redes Neurais de Computação
6.
Medicine (Baltimore) ; 100(42): e27406, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34678867

RESUMO

ABSTRACT: The transtheoretical model (TTM) is a promising approach to the promotion of behavior change, but it remains to be established whether there is an association between the TTM approach and intradialytic exercise among patients on hemodialysis (HD) with low motivation to exercise in a real-world setting.This retrospective cohort study, conducted in a regional hospital in Japan, included adult outpatients receiving HD 3 times per week who had never participated in intradialytic pedaling exercise despite the encouragement of the HD personnel. Patients were divided into 2 groups according to HD weekday. Patients undergoing HD on Tuesday, Thursday, and Saturday were encouraged by the HD unit team to exercise during HD based on the TTM (exposure group) and those receiving HD on Monday, Wednesday, and Friday were encouraged to exercise as usual (control group). The primary outcome was sustained intradialytic exercise using a leg ergometer, defined as a total of 72 sessions of 30-minute pedaling exercise (duration of at least 6 months).Overall, 85 patients were included in the analysis (mean age: 67.1 ±â€Š11.9 years, 22% female). Of 33 patients in the exposure group, 10 (30%) maintained intradialytic exercise, compared with 2 of 52 patients (4%) in the control group. Log-binomial regression models with stabilized inverse probability of treatment weighting showed a significant association between the TTM approach and sustained intradialytic exercise (adjusted risk ratio 9.23 [95% confidence interval 2.13-40.00]). There were no exercise-related cardiovascular events.Among patients with low motivation to exercise during HD, use of the TTM approach in clinical practice was associated with sustained intradialytic exercise compared with usual care.


Assuntos
Ciclismo/fisiologia , Aconselhamento/métodos , Falência Renal Crônica/terapia , Diálise Renal/métodos , Modelo Transteórico , Idoso , Idoso de 80 Anos ou mais , Ciclismo/psicologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Estilo de Vida Saudável , Humanos , Japão , Falência Renal Crônica/psicologia , Masculino , Pessoa de Meia-Idade , Motivação , Estudos Retrospectivos
7.
Cogn Res Princ Implic ; 6(1): 66, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34674059

RESUMO

While attention has consistently been shown to be biased toward threatening objects in experimental settings, our understanding of how attention is modulated when the observer is in an anxious or aroused state and how this ultimately affects behavior is limited. In real-world environments, automobile drivers can sometimes carry negative perceptions toward bicyclists that share the road. It is unclear whether bicyclist encounters on a roadway lead to physiological changes and attentional biases that ultimately influence driving behavior. Here, we examined whether participants in a high-fidelity driving simulator exhibited an arousal response in the presence of a bicyclist and how this modulated eye movements and driving behavior. We hypothesized that bicyclists would evoke a robust arousal and orienting response, the strength of which would be associated with safer driving behavior. The results revealed that encountering a bicyclist evoked negative arousal by both self-report and physiological measures. Physiological and eye-tracking measures were themselves unrelated, however, being independently associated with safer driving behavior. Our findings offer a real-world demonstration of how arousal and attentional prioritization can lead to adaptive behavior.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Acidentes de Trânsito/prevenção & controle , Nível de Alerta , Ciclismo , Movimentos Oculares , Humanos
8.
Nutrients ; 13(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34684480

RESUMO

This study aimed to analyze the effects of live high-train low method (LH-TL) and intermittent hypoxic training (IHT) with a controlled mixed diet on lipid profile in cyclists. Thirty trained male cyclists at a national level with at least six years of training experience participated in the study. The LH-TL group was exposed to hypoxia (FiO2 = 16.5%) for 11-12 h a day and trained under normoxia for 3 weeks. In the IHT group, participants followed the IHT routine three times a week under hypoxia (FiO2 = 16.5%) at lactate threshold intensity. The control group (N) lived and trained under normoxia. The results showed that the 3-week LH-TL method significantly improved all lipid profile variables. The LH-TL group showed a significant increase in HDL-C by 9.0% and a decrease in total cholesterol (TC) by 9.2%, LDL-C by 18.2%, and triglycerides (TG) by 27.6%. There were no significant changes in lipid profiles in the IHT and N groups. ∆TG and ∆TC were significantly higher in the LH-TL group compared to the N group. In conclusion, hypoxic conditions combined with a mixed diet can induce beneficial changes in lipid profile even in highly trained athletes. The effectiveness of the hypoxic stimulus is closely related to the hypoxic training method.


Assuntos
Ciclismo , Dieta , Hipóxia/sangue , Lipídeos/sangue , Aterosclerose/sangue , Composição Corporal , Peso Corporal , Humanos , Masculino , Adulto Jovem
9.
Nutrients ; 13(10)2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34684557

RESUMO

The main aim of this study was to evaluate the effects of six days of tri-sodium phosphate (SP) supplementation on the cardiorespiratory system and gross efficiency (GE) during exercise under hypoxia in cyclists. Twenty trained male cyclists received SP (50 mg·kg-1 of fat-free mass/day) or placebo for six days in a randomized, cross-over study, with a three-week washout period between supplementation phases. Before and after each supplementation phase, the subjects performed an incremental exercise test to exhaustion under normobaric hypoxia (FiO2 = 16%, ~2500 m). It was observed that short-term SP supplementation led to a decrease in heart rate, an increase in stroke volume, and an improvement in oxygen pulse (VO2/HR) during low and moderate-intensity exercise under hypoxia. These changes were accompanied by an increase in the serum inorganic phosphate level by 8.7% (p < 0.05). No significant changes were observed in serum calcium levels. GE at a given workload did not change significantly after SP supplementation. These results indicated that SP promotes improvements in the efficiency of the cardiorespiratory system during exercise in a hypoxic environment. Thus, SP supplementation may be beneficial for endurance exercise in hypoxia.


Assuntos
Ciclismo/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Suplementos Nutricionais , Hipóxia/fisiopatologia , Fosfatos/farmacologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Teste de Esforço , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipóxia/terapia , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Fosfatos/sangue , Resistência Física/efeitos dos fármacos , Volume Sistólico/efeitos dos fármacos
10.
BMC Geriatr ; 21(1): 603, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702189

RESUMO

BACKGROUND: South Korea has a rapidly ageing population. This study aimed to provide epidemiologic data and to identify the characteristics of the patterns and clinical outcomes of two-wheeled vehicle-related injuries (bicycle and motorcycle) in elderly riders. METHODS: This study retrospectively analyzed data from the National Emergency Department Information System from 2016 to 2018. Adult patients (≥ 20 years old) who were injured while using two-wheeled vehicles were included. Elderly patients were defined as being 65 years and older. The analysis was performed for 65,648 bicycle-related injuries (15,272 elderly patients) and 87,855 motorcycles-related injuries (17,292 elderly patients). RESULTS: In emergency departments (EDs), the average injury severity score (ISS) for motorcycle-related accidents was 9.8 ± 11.2 in the younger group and 14.1 ± 14.7 in the elderly group (p = 0.001). In addition, the average ISS of bicycle-related accidents was 7.1 ± 8.9 in the younger group and 10.5 ± 12.3 in the elderly group (p = 0.001). Two-wheeled vehicle accident mortality rates of elderly riders (0.9% for bicycle and 1.8% for motorcycle in the ED; 4.1% for bicycle and 3.8% for motorcycle in the hospital) were more than twice those of younger riders. The elderly stayed in the hospital longer than younger patients (485.2 ± 543.0 h vs 336.8 ± 385.5 h, p = 0.001) for bicycle-related injuries. They also stayed longer for motorcycle-related injuries (529 ± 598.6 h vs 452.0 ± 543.55 h, p = 0.001). The logistic regression analysis showed that age ≥ 65 years was an independent factor associated with severe trauma (ISS ≥ 16) for both bicycle-related injuries (adjusted odds ratio [OR] 2.185 [95% Confidence Interval (CI) 2.072-2.303]) and motorcycle-related injuries (adjusted OR 1.220 [95% CI 1.137-1.287]). CONCLUSION: Two-wheeled vehicle-related injuries in the elderly were associated with higher ISS, length of hospital stay, and mortality than in younger riders. Analysing the characteristics of two-wheeled vehicle-related injuries in the elderly can be the basis for planning to reduce and prevent injuries in elderly riders.


Assuntos
Motocicletas , Ferimentos e Lesões , Acidentes de Trânsito , Idoso , Ciclismo , Humanos , República da Coreia/epidemiologia , Estudos Retrospectivos , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/epidemiologia
11.
Head Face Med ; 17(1): 36, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470621

RESUMO

BACKGROUND: Electric bikes (E-bikes) and powered scooters (P-scooters) have become increasingly popular modes of public transportation, but they have been associated with injuries of all kinds, including dental trauma. Helmet use is promoted as a means of reducing injuries in accidents involving motorized and unmotorized vehicles. The aim of the study was to evaluate the impact of helmet use on the number and severity of oral and maxillofacial injuries caused by E-bikes and P-scooters. METHODS: A retrospective cross-sectional study design was used. The cohort included all patients referred to the emergency department of a tertiary medical center in 2014-2020 with oral and maxillofacial injuries involving E-bikes or P-scooters. Data were collected from the medical files on demographics, types of injuries, circumstances of occurrence, work-up, treatment, and outcome. Use of a helmet was recorded in each case. RESULTS: Of the total 1417 patients referred to the emergency department for E-bike and P-scooter-related trauma, 62 had oral and maxillofacial injuries, including 57 riders and 5 pedestrians. All had hard- or soft-tissue injuries; 20 (32.2%) had head injuries and 22 (35.5%) had dentoalveolar injuries. Eleven riders had worn a helmet at the time of injury (17.7%). Helmet use was associated with time of injury (weekday/weekend, daytime/night-time), type of motorized vehicle (E-bike or P-scooter), head injury, and number of bone fractures. Head injuries occurred more often on the weekend (57.9%) than during the week (20.9%) and were more likely to occur in riders who were not protected by a helmet (37.3% vs 18.2%). Patients who used helmets also had a lower rate of fractured bones (18.2%) and dentoalveolar injuries (23.7%) than patients who did not (68.8 and 37.3%, respectively). Interestingly, helmet use had no protective effect on soft-tissue injuries. CONCLUSIONS: Helmet use by E-bike and P-scooter riders decreased the probability of head injury and of hard tissue and dentoalveolar injuries. These results may provide guidance for effective legislation and regulation of helmet use and improved treatment protocols for general and dental physicians.


Assuntos
Dispositivos de Proteção da Cabeça , Traumatismos Maxilofaciais , Acidentes de Trânsito , Ciclismo , Estudos Transversais , Humanos , Traumatismos Maxilofaciais/epidemiologia , Traumatismos Maxilofaciais/etiologia , Traumatismos Maxilofaciais/prevenção & controle , Estudos Retrospectivos
12.
Sensors (Basel) ; 21(17)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34502704

RESUMO

During the last decade, bicycles equipped with sensors became an essential tool for research, particularly for studies analyzing the lateral passing distance between motorized vehicles and bicycles. The objective of this article is to describe a low-cost open-source sensor called one metre plus (1m+) capable of measuring lateral passing distance, registering the geographical position of the cyclist, and video-recording the trip. The plans, codes, and schematic design are open and therefore easily accessible for the scientific community. This study describes in detail the conceptualization process, the characteristics of the device, and the materials from which they are made. The study also provides an evaluation of the product and describes the sensor's functionalities and its field of application. The objective of this project is to democratize research and develop a platform/participative project that offers tools to researchers worldwide, in order to standardize knowledge sharing and facilitate the comparability of results in various contexts.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Ciclismo , Objetivos , Gravação em Vídeo
13.
Sensors (Basel) ; 21(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34502790

RESUMO

Appropriate cycling cleat adjustment could improve triathlon performance in both cycling and running. Prior recommendations regarding cleat adjustment have comprised aligning the first metatarsal head above the pedal spindle or somewhat forward. However, contemporary research has questioned this approach in triathlons due to the need to run immediately after cycling. Subsequently, moving the pedal cleat posteriorly could be more appropriate. This study evaluated the effectiveness of a triaxial accelerometer to determine acceleration magnitudes of the trunk in outdoor cycling in two different bicycle cleat positions and the consequential impact on trunk acceleration during running. Seven recreational triathletes performed a 20 km cycle and a 5 km run using their own triathlon bicycle complete with aerodynamic bars and gearing. Interpretation of data was evaluated based on cadence changes whilst triathletes cycled in an aerodynamic position in two cleat positions immediately followed by a self-paced overground run. The evaluation of accelerometer-derived data within a characteristic overground setting suggests a significant increase in total trunk acceleration magnitude during cycling with a posterior cleat with significant increases to longitudinal acceleration (p = 0.04) despite a small effect (d = 0.2) to the ratings of perceived exertion (RPE). Cycling with a posterior cleat significantly reduced longitudinal trunk acceleration in running and overall acceleration magnitudes (p < 0.0001) with a large effect size (d = 0.9) and a significant reduction in RPE (p = 0.02). In addition, running after cycling in a posterior cleat was faster compared to running after cycling in a standard cleat location. Practically, the magnitude of trunk acceleration during cycling in a posterior cleat position as well as running after posterior cleat cycling differed from that when cycling in the fore-aft position followed by running. Therefore, the notion that running varies after cycling is not merely an individual athlete's perception, but a valid observation that can be modified when cleat position is altered. Training specifically with a posterior cleat in cycling might improve running performance when trunk accelerations are analysed.


Assuntos
Ciclismo , Corrida , Aceleração , Humanos
14.
Trials ; 22(1): 621, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526100

RESUMO

BACKGROUND: Colorectal cancer is associated with secondary sarcopenia (muscle loss) and myosteatosis (fatty infiltration of muscle) and patients who exhibit these host characteristics have poorer outcomes following surgery. Furthermore, patients, who undergo curative advanced rectal cancer surgery such as pelvic exenteration, are at risk of skeletal muscle loss due to immobility, malnutrition and a post-surgical catabolic state. Neuromuscular electrical stimulation (NMES) may be a feasible adjunctive treatment to help ameliorate these adverse side-effects. Hence, the purpose of this study is to investigate NMES as an adjunctive pre- and post-operative treatment for rectal cancer patients in the radical pelvic surgery setting and to provide early indicative evidence of efficacy in relation to key health outcomes. METHOD: In a phase II, double-blind, randomised controlled study, 58 patients will be recruited and randomised (1:1) to either a treatment (NMES plus standard care) or placebo (sham-NMES plus standard care) group. The intervention will begin 2 weeks pre-operatively and continue for 8 weeks after exenterative surgery. The primary outcome will be change in mean skeletal muscle attenuation, a surrogate marker of myosteatosis. Sarcopenia, quality of life, inflammatory status and cancer specific outcomes will also be assessed. DISCUSSION: This phase II randomised controlled trial will provide important preliminary evidence of the potential for this adjunctive treatment. It will provide guidance on subsequent development of phase 3 studies on the clinical benefit of NMES for rectal cancer patients in the radical pelvic surgery setting. TRIAL REGISTRATION: Protocol version 6.0; 05/06/20. ClinicalTrials.gov NCT04065984 . Registered on 22 August 2019; recruiting.


Assuntos
Terapia por Estimulação Elétrica , Neoplasias Retais , Sarcopenia , Ciclismo , Estimulação Elétrica , Terapia por Estimulação Elétrica/efeitos adversos , Humanos , Qualidade de Vida , Neoplasias Retais/complicações , Neoplasias Retais/cirurgia , Sarcopenia/diagnóstico , Sarcopenia/etiologia , Sarcopenia/terapia
15.
Medicina (Kaunas) ; 57(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34577846

RESUMO

Background and objective: Existing research shows that the sex differences in distance-limited ultra-cycling races decreased with both increasing race distance and increasing age. It is unknown, however, whether the sex differences in time-limited ultra-cycling races will equally decrease with increasing race distance and age. This study aimed to examine the sex differences regarding performance for time-limited ultra-cycling races (6, 12, and 24 h). Methods: Data were obtained from the online database of the Ultra-Cycling Marathon Association (UMCA) of time-limited ultra-cycling races (6, 12, and 24 h) from the years 1983-2019. A total of 18,241 race results were analyzed to compare cycling speed between men and women by calendar year, age group (<29; 30-39; 40-49; 50-59; 60-69; >70 years), and race duration. Results: The participation of both men (85.1%) and women (14.9%) increased between 1983 and 2019. The age of peak performance was between 40 and 59 years for men and between 30 and 59 years for women. Between 2000 and 2019, more men (63.1% of male participants and 52.2% of female participants) competed in 24 h races. In the 24 h races, the sex difference decreased significantly in all age groups. Men cycled 9.6% faster than women in the 12 h races and 4% faster in the 24 h races. Both women and men improved their performance significantly across the decades. Between 2000 and 2019, the improvement in the 24 h races were 15.6% for men and 21.9% for women. Conclusion: The sex differences in cycling speed decreased between men and women with increasing duration of ultra-cycling races and with increasing age. Women showed a greater performance improvement than men in the last 20 years. The average cycling speed of men and women started to converge in the 24 h races.


Assuntos
Desempenho Atlético , Caracteres Sexuais , Adulto , Idoso , Ciclismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resistência Física , Fatores Sexuais
16.
Accid Anal Prev ; 161: 106387, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34492561

RESUMO

INTRODUCTION: Mental fatigue has been shown to negatively affect motor and sport performance. To date, however, no research focused on assessing the effects of mental fatigue on hazard perception in young cyclists who are highly vulnerable in traffic, especially after school. Therefore, the purpose of this study was to examine the influence of induced mental fatigue on hazard perception and anticipation in young cyclists using a novel Virtual Reality bicycle simulator. METHODS: In this randomised, counterbalanced, cross-over investigation, forty-eight young cyclists cycled through a Virtual Environment (VE) in which they were confronted with eight simple and six complex traffic situations. Simple traffic situations are considered events including only one other actor can cause a dangerous situation while complex traffic situations include multiple actors than contribute to the dangerous situation. Half of the children were mentally fatigued using the Stroop colour-word task while the other half immediately started the VR hazard perception test. On the second test occasion, one month later, the other half of the group was mentally fatigued. RESULTS: The results demonstrate that mentally fatigued cyclists fixated the relevant areas of interest (AOIs) in the simple and complex later and showed delayed response times for the complex hazards. Mental fatigue, however, did not alter the speed with which participants cycled through the virtual environment and did not change the hazard perception score. CONCLUSION: To our knowledge, this was the first study to investigate the effect of mental fatigue in young cyclists with an innovative VR hazard perception simulator. Due to increased mental fatigue, young cyclists might have experienced more episodes of fatigue-related mind-wandering and a deterioration of selective attention for the task at hand. This resulted in a less thorough visual inspection of the scene and delayed braking responses.


Assuntos
Realidade Virtual , Acidentes de Trânsito , Ciclismo , Criança , Humanos , Fadiga Mental , Negociação
17.
Sensors (Basel) ; 21(18)2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34577323

RESUMO

The purpose of this study was to evaluate the validity and reliability of a tire pressure sensor (TPS) cycling power meter against a gold standard (SRM) during indoor cycling. Twelve recreationally active participants completed eight trials of 90 s of cycling at different pedaling and gearing combinations on an indoor hybrid roller. Power output (PO) was simultaneously calculated via TPS and SRM. The analysis compared the paired 1 s PO and 1 min average PO per trial between devices. Agreement was assessed by correlation, linear regression, inferential statistics, effect size, and Bland-Altman LoA. Reliability was assessed by ICC and CV comparison. TPS showed near-perfect correlation with SRM in 1 s (rs = 0.97, p < 0.001) and 1-min data (rs = 0.99, p < 0.001). Differences in paired 1 s data were statistically significant (p = 0.04), but of a trivial magnitude (d = 0.05). There was no significant main effect for device (F(1,9) = 0.05, p = 0.83, ηp2 = 0.97) in 1 min data and no statistical differences between devices by trial in post hoc analysis (p < 0.01-0.98; d < 0.01-0.93). Bias and LoA were -0.21 ± 16.77 W for the 1 min data. Mean TPS bias ranged from 3.37% to 7.81% of the measured SRM mean PO per trial. Linear regression SEE was 7.55 W for 1 min TPS prediction of SRM. ICC3,1 across trials was 0.96. No statistical difference (p = 0.09-0.11) in TPS CV (3.6-5.0%) and SRM CV (4.3-4.7%). The TPS is a valid and reliable power meter for estimating average indoor PO for time periods equal to or greater than 1 min and may have acceptable sensitivity to detect changes under less stringent criteria (±5%).


Assuntos
Ciclismo , Teste de Esforço , Humanos , Modelos Lineares , Reprodutibilidade dos Testes
18.
Int J Equity Health ; 20(1): 208, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526041

RESUMO

BACKGROUND: Cycling for transport provides many health and social benefits - including physical activity and independent access to jobs, education, social opportunities, health care and other services (accessibility). However, some population groups have less opportunity to reach everyday destinations, and public transport stops, by bicycle - owing in part to their greater aversion to riding amongst motor vehicle traffic. Health equity can therefore be improved by providing separated cycleway networks that give more people the opportunity to access places by bicycle using traffic-free routes. The aim of this study was to assess the health equity benefits of two bicycle infrastructure development scenarios - a single cycleway, and a complete network of cycleways - by examining the distributions of physical activity and accessibility benefits across gender, age and income groups. METHODS: Travel survey data collected from residents in Sydney (Australia) were used to train a predictive transport mode choice model, which was then used to forecast the impact of the two intervention scenarios on transport mode choice, physical activity and accessibility. The latter was measured using a utility-based measure derived from the mode choice model. The distributions of the forecast physical activity and accessibility benefits were then calculated across gender, age and income groups. RESULTS: The modelled physical activity and accessibility measures improve in both intervention scenarios. However, in the single cycleway scenario, the benefits are greatest for the male, high-income and older age groups. In the complete network scenario, the benefits are more equally distributed. Forecast increases in cycling time are largely offset by decreases in walking time - though the latter is typically low-intensity physical activity, which confers a lesser health benefit than moderate-intensity cycling. CONCLUSIONS: Separated cycleway infrastructure can be used to improve health equity by providing greater opportunities for transport cycling in population groups more averse to riding amongst motor vehicle traffic. Disparities in the opportunity to access services and economic/social activities by bicycle - and incorporate more physical activity into everyday travel - could be addressed with connected, traffic-free cycleway networks that cater to people of all genders, ages and incomes.


Assuntos
Ciclismo , Planejamento Ambiental , Exercício Físico , Equidade em Saúde , Adolescente , Adulto , Austrália , Planejamento Ambiental/estatística & dados numéricos , Feminino , Humanos , Renda/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Ir Med J ; 114(7): 412, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34520647

RESUMO

Introduction The Sars-CoV-2 pandemic led to a national lockdown in Ireland from March 12th to June 7th, 2020. The present study aimed to assess the change in the pattern of cycling attendances to an Irish ED during a pandemic. Methods This is a retrospective before-and-after study carried out at a university hospital ED. We compared cycling attendances during Lockdown (LD) (13th March-7th June 2020) with Pre-Lockdown (PLD) (January 1st-March 12th, 2020). Furthermore, we also compared lockdown to an historical control period during the equivalent dates in 2019 (i.e. March 13th-June 7th, 2019) Results There were 151 cycling attendances during LD, 122 in PLD and 164 during the control period. The number of cyclists presenting during "rush hour traffic" in the LD period was 30 (19.9%) versus 42 (34.4%) during PLD (p<0.05) and 51 (31.1%) during the control period (p<0.05). During LD, 8 (5.3%) collisions involved a motor vehicle compared to 26 (21.3%) in PLD (p<0.05) and 43 (26.2%) during the control period (p<0.05). Conclusion Lockdown did not result in increased cycling attendances to this ED. The patients who did sustain a cycling-related injury during lockdown were less likely to have collided with a motor vehicle compared to the control period. The reduction in motor vehicle collisions could be attributed to less traffic congestion and highlights the potential benefits of road-user segregation.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Ciclismo/lesões , COVID-19/epidemiologia , Controle de Doenças Transmissíveis/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Adulto , Feminino , Humanos , Irlanda , Masculino , Estudos Retrospectivos , Fatores de Risco , Segurança
20.
Am J Physiol Regul Integr Comp Physiol ; 321(5): R687-R698, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34549627

RESUMO

Recently it was documented that fatiguing, high-intensity exercise resulted in a significant attenuation in maximal skeletal muscle mitochondrial respiratory capacity, potentially due to the intramuscular metabolic perturbation elicited by such intense exercise. With the utilization of intrathecal fentanyl to attenuate afferent feedback from group III/IV muscle afferents, permitting increased muscle activation and greater intramuscular metabolic disturbance, this study aimed to better elucidate the role of metabolic perturbation on mitochondrial respiratory function. Eight young, healthy males performed high-intensity cycle exercise in control (CTRL) and fentanyl-treated (FENT) conditions. Liquid chromatography-mass spectrometry and high-resolution respirometry were used to assess metabolites and mitochondrial respiratory function, respectively, pre- and postexercise in muscle biopsies from the vastus lateralis. Compared with CTRL, FENT yielded a significantly greater exercise-induced metabolic perturbation (PCr: -67% vs. -82%, Pi: 353% vs. 534%, pH: -0.22 vs. -0.31, lactate: 820% vs. 1,160%). Somewhat surprisingly, despite this greater metabolic perturbation in FENT compared with CTRL, with the only exception of respiratory control ratio (RCR) (-3% and -36%) for which the impact of FENT was significantly greater, the degree of attenuated mitochondrial respiratory capacity postexercise was not different between CTRL and FENT, respectively, as assessed by maximal respiratory flux through complex I (-15% and -33%), complex II (-36% and -23%), complex I + II (-31% and -20%), and state 3CI+CII control ratio (-24% and -39%). Although a basement effect cannot be ruled out, this failure of an augmented metabolic perturbation to extensively further attenuate mitochondrial function questions the direct role of high-intensity exercise-induced metabolite accumulation in this postexercise response.


Assuntos
Metabolismo Energético , Exercício Físico , Mitocôndrias Musculares/metabolismo , Contração Muscular , Músculo Quadríceps/metabolismo , Adulto , Analgésicos Opioides/administração & dosagem , Ciclismo , Respiração Celular , Fentanila/administração & dosagem , Voluntários Saudáveis , Humanos , Injeções Espinhais , Masculino , Neurônios Aferentes/efeitos dos fármacos , Neurônios Aferentes/fisiologia , Músculo Quadríceps/inervação , Distribuição Aleatória , Adulto Jovem
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