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1.
Sensors (Basel) ; 22(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35009945

RESUMO

A large number of power meters have become commercially available during the last decades to provide power output (PO) measurement. Some of these power meters were evaluated for validity in the literature. This study aimed to perform a review of the available literature on the validity of cycling power meters. PubMed, SPORTDiscus, and Google Scholar have been explored with PRISMA methodology. A total of 74 studies have been extracted for the reviewing process. Validity is a general quality of the measurement determined by the assessment of different metrological properties: Accuracy, sensitivity, repeatability, reproducibility, and robustness. Accuracy was most often studied from the metrological property (74 studies). Reproducibility was the second most studied (40 studies) property. Finally, repeatability, sensitivity, and robustness were considerably less studied with only 7, 5, and 5 studies, respectively. The SRM power meter is the most used as a gold standard in the studies. Moreover, the number of participants was very different among them, from 0 (when using a calibration rig) to 56 participants. The PO tested was up to 1700 W, whereas the pedalling cadence ranged between 40 and 180 rpm, including submaximal and maximal exercises. Other exercise conditions were tested, such as torque, position, temperature, and vibrations. This review provides some caveats and recommendations when testing the validity of a cycling power meter, including all of the metrological properties (accuracy, sensitivity, repeatability, reproducibility, and robustness) and some exercise conditions (PO range, sprint, pedalling cadence, torque, position, participant, temperature, vibration, and field test).


Assuntos
Ciclismo , Teste de Esforço , Exercício Físico , Humanos , Reprodutibilidade dos Testes , Torque
2.
Nutrients ; 14(1)2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35011078

RESUMO

BACKGROUND: Men and women with valvular heart disease have different risk profiles for clinical endpoints. Non-esterified fatty acids (NEFA) are possibly involved in cardio-metabolic disease. However, it is unclear whether NEFA concentrations are associated with physical performance in patients undergoing transcatheter aortic valve implantation (TAVI) and whether there are sex-specific effects. METHODS: To test the hypothesis that NEFA concentration is associated with sex-specific physical performance, we prospectively analysed data from one hundred adult patients undergoing TAVI. NEFA concentrations, physical performance and anthropometric parameters were measured before and 6 and 12 months after TAVI. Physical performance was determined by a six-minute walking test (6-MWT) and self-reported weekly bicycle riding time. RESULTS: Before TAVI, NEFA concentrations were higher in patients (44 women, 56 men) compared to the normal population. Median NEFA concentrations at 6 and 12 months after TAVI were within the reference range reported in the normal population in men but not women. Men but not women presented with an increased performance in the 6-MWT over time (p = 0.026, p = 0.142, respectively). Additionally, men showed an increased ability to ride a bicycle after TAVI compared to before TAVI (p = 0.034). NEFA concentrations before TAVI correlated with the 6-MWT before TAVI in women (Spearman's rho -0.552; p = 0.001) but not in men (Spearman's rho -0.007; p = 0.964). No association was found between NEFA concentrations and physical performance 6 and 12 months after TAVI. CONCLUSIONS: NEFA concentrations improved into the reference range in men but not women after TAVI. Men but not women have an increased physical performance after TAVI. No association between NEFA and physical performance was observed in men and women after TAVI.


Assuntos
Biomarcadores/sangue , Ácidos Graxos não Esterificados/sangue , Desempenho Físico Funcional , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/cirurgia , Ciclismo , Índice de Massa Corporal , Feminino , Humanos , Masculino , Estudos Prospectivos , Valores de Referência , Fatores de Risco , Fatores Sexuais , Resultado do Tratamento , Caminhada
3.
Ann Otol Rhinol Laryngol ; 131(1): 52-58, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33840222

RESUMO

OBJECTIVES: The popularity of mountain biking (MTB) in the United States has risen in recent years. We sought to identify the prevalence and distribution of MTB associated head and neck injuries presenting to emergency departments across the U.S. and identify risk factors for hospital admission in this patient population. METHODS: The National Electronic Injury Surveillance System (NEISS) was queried for MTB related injuries of the head and neck from 2009 to 2018, with analysis for incidence, age, gender, anatomic site, and diagnoses. RESULTS: A total of 486 cases were identified, corresponding to an estimated 18 952 head and neck MTB related ED visits. Patients were predominantly male (80.7%) and white (69.8%) with a median age of 35 years (interquartile range, 21-46 years). A majority (88.4%) of patients were released from the ED, but a significant proportion of patients were admitted (9.2%) or transferred (1.2%). The most common facial fractures were facial/not specified (35%), nasal bone (29%), mandible (15%), orbit (12%), and zygomaxillary complex (9%). The greatest predictors of hospital admission/transfer were injury to the mouth or neck and avulsion-type injury (P < .001). CONCLUSIONS: MTB results in a significant number of traumatic head and neck injuries nationwide. Patients are primarily adult, white males. The majority of injuries result in discharge from the ED, however a small amount of these patients experience significant morbidity necessitating hospital admission. Understanding the distribution of MTB head and neck injuries may aid in the clinical evaluation of these patients. LEVEL OF EVIDENCE: 4.


Assuntos
Ciclismo/lesões , Traumatismos Craniocerebrais/epidemiologia , Lesões do Pescoço/epidemiologia , Adulto , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia , Adulto Jovem
4.
Accid Anal Prev ; 165: 106510, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34896906

RESUMO

While cycling is promoted as a clean, energy-efficient mode of transport generating physical activity, the number of injured cyclists must decrease to achieve traffic safety goals. The extent of the single bicycle crashes (SBCs) and crash causes are rather well studied. This study expands this knowledge by focusing on differences in injury severity. The aim of the study is to investigate the relationship between injury severity and characteristics of the crash and the cyclist with focus on SBCs. Furthermore, injury risk is calculated for different age classes and sexes, as well as for different purposes of the trip. The results are based on injured cyclists in Sweden (N = 105,836) registered in STRADA, 2010-2019, by both the police and accident and emergency departments (A&Es), with a special focus on injury severity reported by the A&Es. Binary logistic regression was applied to analyse how the odds of being severely injured differed for different cyclists and situations. Results from of the National Travel Survey, 2011-2016, were used to study differences in distance travelled with respect to sex, age group and purpose of the trip. Given that the cyclist is injured in an SBC, the results show a higher probability of being severely injured (maximal AIS 3 or more) for cyclists 45 years or older compared to younger cyclists, for males compared to females and for cyclists not wearing a helmet compared to cyclists wearing a helmet. A higher probability for severe injury was also found for crashes occurring during leisure trips compared to work/school trips, crashes occurring during weekdays compared to weekends and crashes at intersections and road stretches compared to pedestrian and cycle paths. Furthermore, the risk of being severely injured in an SBC per km travelled was higher for cyclists aged 45 and older and during a leisure trip.


Assuntos
Acidentes de Trânsito , Ciclismo , Serviço Hospitalar de Emergência , Feminino , Humanos , Modelos Logísticos , Masculino , Suécia/epidemiologia
5.
J Sci Med Sport ; 25(1): 70-74, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34446367

RESUMO

OBJECTIVES: To investigate the impact of fast-start, steady or slow-start strategies of the running fraction in sprint triathlon on oxygen consumption, perception of fatigue and blood lactate. DESIGN: Thirteen male triathletes (age; 36.4 ±â€¯10.8 yy, height 174.8 ±â€¯7.9 cm, body mass 70.6 ±â€¯11.1 kg; V'O2max 62.4 ±â€¯8.9 ml min-1 kg-1; mean ±â€¯SD) attended the laboratory five times in order to complete two incremental tests and three subsequent cycle-run sessions. METHODS: Three experimental randomized sessions with different effort distribution were compared. The intensities of the 1st running kilometer were set at 95%, 100% and 105% of the second ventilatory threshold for slow, continuous and fast start protocol respectively. Measurement of ventilatory variables, blood lactate and ratings of perceived exertion were collected throughout all sessions. RESULTS: A meaningful difference was found between the slow versus fast start protocol in V'O2 (SE = 0.58, P = 0.0005), BLa- (SE = 0.21, P = 0.0097), HR (SE = 1.23, P = 0.0011) and RPE (SE = 2.83, P = 0.0047) values. No differences in-between protocols were found at the end of the running bout whatever the condition. CONCLUSIONS: Differences in physiological parameters were found between protocols during the first kilometer, not at the end of exercise. The fast start appears to be more correct and useful for performance in racing setting and may be used as a strategy without impacting the remaining running bout in ecological setting.


Assuntos
Ciclismo , Natação , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Testes de Função Respiratória
6.
Sci Total Environ ; 806(Pt 2): 150627, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34592271

RESUMO

Measures promoting active mobility - walking or cycling - are often seen as an effective strategy to meet multiple urban objectives. The advantages of such behavioural changes cover multiple dimensions at public and individual level, including positive impacts on health, safety, climate, economy, environment and air quality. However, there is still a considerable potential for increasing the uptake of active mobility in urban areas. This paper explores the determinants of active mobility choice and compares the demographic, socio-economic and cultural factors that influence it. The methodology combines extensive survey data, an EU-wide transport model and detailed indicators of external costs of transport with a Gradient Boosting Machine Learning approach. The model based scenarios quantify the benefit in terms of external costs savings from increasing active mobility shares. Such savings - at EU level, can reach the amount of 15 billion euro per year for a shift of 10% of trips to active mobility modes.


Assuntos
Poluição do Ar , Ciclismo , Clima , Renda , Transportes , Caminhada
7.
Accid Anal Prev ; 164: 106470, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34768116

RESUMO

Most research concerned with cyclists' safety has been focused on the crash risk (i.e. their objective safety). However, there has been a growing interest in the perceived level of this risk (i.e. the subjective safety of cyclists). Crash risk and subjective risk perception in urban cycling appear to be mostly well aligned. For example, reduced speed limits have been found to reduce both objective and subjective risks (although there is also evidence for some incongruences). This absolute number of incidents could be misleading, as it does not account for potential differences in cycling volume (i.e. cyclists are likely to prefer streets with reduced speed limits). Thus, it may be important to adjust the absolute number of incidents relative number to the local cycling volume. In this research, we investigate the relation of cycling crashes and subjective risk perception (operationalized through reports from a crowd-sourcing project) for different types of cycling infrastructure and different speed limits, while accounting for the local cycling volume. We find that the absolute number of VGI reports and crashes can be misleading: whereas the absolute incident numbers, for example, suggest few benefits of cycling lanes and tracks, adjusting for the cycling volume reveals an increase of both objective and subjective safety as compared to streets without cycling infrastructure. We also identify situations where cyclists apparently underestimate the crash risk (i.e. on cycleways opposing the cars' traveling direction, and at streets with a speed limit of 30 km/h intersecting streets with higher speed limits). Additional research is required to understand the sources of these discrepancies, and how to make cyclists aware of them.


Assuntos
Acidentes de Trânsito , Ciclismo , Automóveis , Conscientização , Humanos , Percepção
8.
Accid Anal Prev ; 164: 106471, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34773873

RESUMO

Cyclists are vulnerable road users and face disproportionately high rates of road trauma, especially in low- and middle-income countries. Behaviour of road users is a system outcome, and thus studying cyclist behaviours can identify problems in the whole road transport system and assist in generating long-lasting, cost-effective solutions to promote cyclist safety. This study aims to investigate the similarities and disparities of cycling behaviour among countries with different income levels and cycling prevalence, and the relationships among cyclist demographic characteristics, behaviours and crash involvement. It applies the Cycling Behaviour Questionnaire (CBQ) to measure the behaviour of cyclists in three countries: Australia (high-income, emerging cycling country), China (mid-income, traditional cycling country) and Colombia (low-income, emerging cycling country). A total of 1094 cyclists (Australia 347, China 368, and Colombia 379) with a mean age of 31.8 years completed the online questionnaire. Confirmatory Factor Analysis was used to examine the factorial structure of the CBQ. The results showed that the three-factor CBQ (i.e., Traffic Violations, Errors and Positive Behaviours) had a stable and uniform factorial structure across all three countries. Cyclists reported more frequent positive behaviours than risky behaviours across all three countries. The Australian cyclists reported more positive behaviours and fewer violations than cyclists from the other countries, which is likely to reflect the road environment, policy and enforcement differences. Male cyclists tended to engage in more risky riding than females and reported more crash involvement. Older cyclists reported less risky riding and less involvement in crashes than younger cyclists. Cyclists who rode more often reported more frequent risky riding. The study helps understand the prevalence of risky/positive cyclist behaviours among countries and provides insights for developing systematic countermeasures to improve cycling environment and cyclist safety.


Assuntos
Acidentes de Trânsito , Ciclismo , Adulto , Austrália , Colômbia , Feminino , Humanos , Masculino , Inquéritos e Questionários
9.
Accid Anal Prev ; 164: 106475, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34798566

RESUMO

Bicycles gained significant popularity among Americans in 2020. Greater investment in adequate bicycle safety facilities will be needed. Crash data from police will undoubtedly play a role in decision-making. This research evaluated the data quality of text narratives in police reports on bicycle crashes. The aims were to identify situations in which police officers wrote more detail in the narrative text, investigate if longer reports translate to more in-depth crash descriptions, examine the extent to which narrative texts cover details useful for those charged with bicycle safety. This is a 4-year retrospective cohort study of vehicle-vs-bicycle crashes that occurred between January 1, 2009, and December 31, 2012, in Boston, Massachusetts (USA). Police reports were matched with the Pedestrian and Bicycle Crash Analysis Tool (PBCAT) to measure how much information was captured and when reports were more likely to capture more information. Police reports only captured most information in one area of the standardized form (Crash Typing), with average total missingness of over 75%. Longer reports did reduce the amount of missingness, and officers were more likely to write longer reports when they were on the crash site, when there was an injury, when the crash involved an extended car door, and during the day. A 100% increase in the report's words was associated with a four-percentage point reduction in PBCAT missingness. While longer reports result in less missingness when measured against the standardized crash form, the average report still misses most of the information that the form would capture. We recommend that police departments adopt a standardized form to facilitate information capture at the scene of bicycle-vehicle crashes.


Assuntos
Pedestres , Polícia , Acidentes de Trânsito/prevenção & controle , Ciclismo , Humanos , Estudos Retrospectivos
10.
Accid Anal Prev ; 164: 106476, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34844065

RESUMO

Car-electric bicycle (e-bike) accidents have been the subject of strong attention due to the widespread usage of e-bikes and a high casualty rate for their riders. Manually conducted accident reconstruction is based on the trial-and-error method with a limited number of parameter combinations, which makes it time-consuming and subjective. This paper aims to develop an intelligent method for accurate, high-efficient reconstruction of accidents involving cars and e-bikes. First, an automatic operation framework, which can drive the MADYMO program and perform results analysis automatically, was built with four multi-objective optimization algorithms available - NSGA-Ⅱ, NCGA, AMGA, and MOPS; The optimization condition was controlled with 12 design variables, 5 objective functions, and 3 constraints. Then, a real e-bike accident with surveillance video was reconstructed through the proposed framework to verify its validity using comparisons of simulated and actual rest positions, initial variables, kinematic response, and head injury. Lastly, the simulation data were used to study the effects of the initial variables on objectives with a multiple linear regression model. The results showed that it took only about 24 h in total for optimization with 480 automatic operations. Optimal conditions were searched at run numbers of 469, 430, 323, and 474 for NSGA-Ⅱ, NCGA, AMGA, and MOPS, respectively. NSGA-Ⅱ had the best performance for e-bike accident reconstruction with average errors of objectives below 5%; Good consistencies for the rider's kinematic response in three stages after collision were observed between simulations and screenshots from the surveillance video, as well as for velocities between the simulation and those estimated from the surveillance video and for head injury between the simulation and the medical report. In contrast to the subjective trial-and-error method that highly depends on the analyst's intuition and experience, this intelligent method is based on multi-objective optimization theory, with which results can be optimized in terms of the automatic change of initial variables. All the above comparisons demonstrate that the method is valid for effectively improving efficiency without simultaneously compromising accuracy. This intelligent method, coupling automatic simulation and multi-objective optimization, can also be applied to other accident reconstructions, and the significant order of initial variables' effects on objectives can provide recommendations for further reconstructions.


Assuntos
Ciclismo , Traumatismos Craniocerebrais , Acidentes de Trânsito , Automóveis , Simulação por Computador , Humanos
11.
Comput Intell Neurosci ; 2021: 5486328, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912446

RESUMO

The demand forecast of shared bicycles directly determines the utilization rate of vehicles and projects operation benefits. Accurate prediction based on the existing operating data can reduce unnecessary delivery. Since the use of shared bicycles is susceptible to time dependence and external factors, most of the existing works only consider some of the attributes of shared bicycles, resulting in insufficient modeling and unsatisfactory prediction performance. In order to address the aforementioned limitations, this paper establishes a novelty prediction model based on convolutional recurrent neural network with the attention mechanism named as CNN-GRU-AM. There are four parts in the proposed CNN-GRU-AM model. First, a convolutional neural network (CNN) with two layers is used to extract local features from the multiple sources data. Second, the gated recurrent unit (GRU) is employed to capture the time-series relationships of the output data of CNN. Third, the attention mechanism (AM) is introduced to mining the potential relationships of the series features, in which different weights will be assigned to the corresponding features according to their importance. At last, a fully connected layer with three layers is added to learn features and output the prediction results. To evaluate the performance of the proposed method, we conducted massive experiments on two datasets including a real mobile bicycle data and a public shared bicycle data. The experimental results show that the prediction performance of the proposed model is better than other prediction models, indicating the significance of the social benefits.


Assuntos
Ciclismo , Redes Neurais de Computação , Previsões
12.
BMC Musculoskelet Disord ; 22(1): 1044, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34911507

RESUMO

BACKGROUND: Stationary cycling is commonly used for postoperative rehabilitation of physical disabilities; however, few studies have focused on the three-dimensional (3D) kinematics of rehabilitation. This study aimed to elucidate the three-dimensional lower limb kinematics of people with healthy musculoskeletal function and the effect of sex and age on kinematics using a controlled bicycle configuration. METHODS: Thirty-one healthy adults participated in the study. The position of the stationary cycle was standardized using the LeMond method by setting the saddle height to 85.5% of the participant's inseam. The participants maintained a pedaling rate of 10-12 km/h, and the average value of three successive cycles of the right leg was used for analysis. The pelvis, hip, knee, and ankle joint motions during cycling were evaluated in the sagittal, coronal, and transverse planes. Kinematic data were normalized to 0-100% of the cycling cycle. The Kolmogorov-Smirnov test, Mann-Whitney U test, Kruskal-Wallis test, and k-fold cross-validation were used to analyze the data. RESULTS: In the sagittal plane, the cycling ranges of motion (ROMs) were 1.6° (pelvis), 43.9° (hip), 75.2° (knee), and 26.9° (ankle). The coronal plane movement was observed in all joints, and the specific ROMs were 6.6° (knee) and 5.8° (ankle). There was significant internal and external rotation of the hip (ROM: 11.6°), knee (ROM: 6.6°), and ankle (ROM: 10.3°) during cycling. There was no difference in kinematic data of the pelvis, hip, knee, and ankle between the sexes (p = 0.12 to 0.95) and between different age groups (p = 0.11 to 0.96) in all anatomical planes. CONCLUSIONS: The kinematic results support the view that cycling is highly beneficial for comprehensive musculoskeletal rehabilitation. These results might help clinicians set a target of recovery ROM based on healthy and non-elite individuals and issue suitable guidelines to patients.


Assuntos
Ciclismo , Articulação do Quadril , Adulto , Fenômenos Biomecânicos , Humanos , Articulação do Joelho , Amplitude de Movimento Articular
13.
Artigo em Inglês | MEDLINE | ID: mdl-34948581

RESUMO

BACKGROUND: The extent to which mountain biking impacts upon the environment is largely determined by rider behaviours. The purpose of this study was to gain a better understanding of how mountain bikers interact with the natural environment and explore their attitudes towards sustainability. METHODS: 3780 European mountain bikers completed an online cross-sectional survey. RESULTS: Connection to nature was an important source of motivation and the use of mountain bike trails has increased rider's appreciation of and willingness to protect nature, with a large majority having taken direct action to do so. Mountain bikers are prepared to contribute towards trail maintenance through the provision of labour or financially. Although most mountain bikers make use of wet trails and illegal trails, incidence of conflict is relatively low. A range of characteristics were identified as being fundamental elements of sustainable trails, both in relation to the sustainability of the trail itself and in terms of wider environmental sustainability. CONCLUSIONS: European mountain bikers care about the sustainability of the natural environment. Self-reported attitudes and behaviours suggest a willingness to reduce environmental impact and actively protect nature.


Assuntos
Ciclismo , Motivação , Atitude , Estudos Transversais , Meio Ambiente , Humanos
14.
Artigo em Inglês | MEDLINE | ID: mdl-34948735

RESUMO

Excessive school bag weight may be a modifiable barrier to active transport to school. This study examined correlates of school bag weight and adolescents' perceptions of excessive school bag weight for walking and cycling to school among New Zealand adolescents living in diverse settlement types. Adolescents (n = 1512; 15.0 ± 1.3 years) completed a questionnaire and had their bag weight (n = 1190) and body weight (n = 1038) measured. Adolescents using active transport and rural adolescents had lighter school bags compared to their counterparts. One-third of adolescents reported excessive school bag weight for walking (31.2%) and cycling (37.2%) to school. Positive correlates of relative school bag weight were female gender (regression coefficient (95% CI): 0.53 (0.13, 0.93)), and underweight (2.21 (1.39, 3.02)), whereas negative correlates were Maori ethnicity (-0.87 (-1.41, -0.32)), overweight (-1.84 (-2.35, -1.34)) and obesity (-3.57 (-4.26, -2.87)), and school location in small urban areas (-2.10 (-4.19, -0.01)), and rural settlements (-3.58 (-5.66, -1.49)). Older adolescents, females, those with greater relative school bag weight, and those experiencing school bag-related pain symptoms and/or fatigue were more likely to report excessive school bag weight for both walking and cycling to school. Future initiatives should target reducing excessive school bag weight, particularly in female and urban adolescents.


Assuntos
Instituições Acadêmicas , Caminhada , Adolescente , Ciclismo , Feminino , Humanos , Nova Zelândia , População Rural
15.
Artigo em Inglês | MEDLINE | ID: mdl-34948984

RESUMO

This study wants to give a contribution for the investigation of sustainable mobility with positive consequences on public health implementing policies starting from cyclists' perceptions. Data were collected by interviewing cyclists along three bike lanes of an urban area of southern Italy through a face-to-face survey. The survey was conducted in Autumn 2019, interviewing a sample of 129 cyclists. In order to identify the critical aspects of the bike paths, both an importance-performance analysis (IPA) and a gap-IPA were performed. The average values of the cyclists' perceptions of each aspect have been considered as performance values. The importance values have been obtained by performing a principal component analysis (PCA), which was helpful also for better defining the service quality phenomenon. From the PCA, six latent constructs can be identified as: "Physical Nuisance"; "Non-physical Nuisance"; "Physical Comfort"; "Non-physical Comfort"; "Protection"; and "Ambience". The results of Gap-IPA confirmed that the criticalities of the bike paths relate to the degree of protection in relation to accidents, and to the degree of nuisance caused by pollution and opposing pedestrians along the path. Based on the conducted analyses, sustainable tourism implementing policies should be oriented in solving the emerged criticalities of the existing bike paths. The results of Gap-IPA are very intuitive and can certainly be helpful for identifying the most convenient strategies.


Assuntos
Ciclismo , Pedestres , Acidentes de Trânsito , Humanos , Itália , Turismo
16.
Nutrients ; 13(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34959861

RESUMO

The current study compared mouth swills containing carbohydrate (CHO), menthol (MEN) or a combination (BOTH) on 40 km cycling time trial (TT) performance in the heat (32 °C, 40% humidity, 1000 W radiant load) and investigates associated physiological (rectal temperature (Trec), heart rate (HR)) and subjective measures (thermal comfort (TC), thermal sensation (TS), thirst, oral cooling (OC) and RPE (legs and lungs)). Eight recreationally trained male cyclists (32 ± 9 y; height: 180.9 ± 7.0 cm; weight: 76.3 ± 10.4 kg) completed familiarisation and three experimental trials, swilling either MEN, CHO or BOTH at 10 km intervals (5, 15, 25, 35 km). The 40 km TT performance did not differ significantly between conditions (F2,14 = 0.343; p = 0.715; η2 = 0.047), yet post-hoc testing indicated small differences between MEN and CHO (d = 0.225) and MEN and BOTH (d = 0.275). Subjective measures (TC, TS, RPE) were significantly affected by distance but showed no significant differences between solutions. Within-subject analysis found significant interactions between solution and location upon OC intensity (F28,196 = 2.577; p < 0.001; η2 = 0.269). While solutions containing MEN resulted in a greater sensation of OC, solutions containing CHO experienced small improvements in TT performance. Stimulation of central CHO pathways during self-paced cycling TT in the heat may be of more importance to performance than perceptual cooling interventions. However, no detrimental effects are seen when interventions are combined.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Carboidratos da Dieta/administração & dosagem , Mentol/administração & dosagem , Antissépticos Bucais/administração & dosagem , Adulto , Temperatura Corporal/efeitos dos fármacos , Regulação da Temperatura Corporal/efeitos dos fármacos , Método Duplo-Cego , Frequência Cardíaca/efeitos dos fármacos , Temperatura Alta/efeitos adversos , Humanos , Umidade , Masculino , Boca , Antissépticos Bucais/química , Sensação Térmica/efeitos dos fármacos , Sede/efeitos dos fármacos
17.
Nutrients ; 13(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34959874

RESUMO

BACKGROUND: Long hyperglycemic episodes trigger complications in type 2 diabetes mellitus (T2DM) patients. Postprandial glucose excursions can be reduced by acute physical activity. However, it is not yet clear which type of exercise has the best effect on postprandial glucose levels. METHODS: Six T2DM patients participated in three 20-min moderate-intensity exercise sessions after breakfast in a randomized order: resistance exercise with whole-body electromyostimulation (WB-EMS), resistance exercise without electromyostimulation (RES) and cycling endurance exercise (END). A continuous glucose monitoring system recorded glucose dynamics. RESULTS: Postprandially-increased glucose levels decreased in all cases. Time to baseline (initial value prior to meal intake) was quite similar for WB-EMS, RES and END. Neither glucose area under the curve (AUC), nor time in range from the start of the experiment to its end (8 h later) differed significantly. A Friedman analysis of variance, however, revealed an overall significant difference for AUC in the post-exercise recovery phase (END seems to have superior effects, but post-hoc tests failed statistical significance). CONCLUSIONS: There are no notable differences between the effects of the different types of exercise on glucose levels, especially when comparing values over a longer period of time.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Estimulação Elétrica , Exercício Físico/fisiologia , Período Pós-Prandial/fisiologia , Análise de Variância , Área Sob a Curva , Ciclismo/fisiologia , Automonitorização da Glicemia , Desjejum , Estudos Cross-Over , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/terapia , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resistência Física/fisiologia , Treinamento de Força , Fatores de Tempo
18.
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
19.
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
20.
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
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