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1.
J Sports Sci ; 36(17): 2018-2024, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29369014

RESUMO

Sampling bias is an issue for research involving cyclists. The heterogeneity of cyclist populations, on the basis of skill level and riding purpose, can generate incorrect inferences about one specific segment of the population of interest. In addition, a more accurate categorization would be helpful when physiological parameters are not available. This study proposes using self-reported data to categorize amateur cyclist types by varying skill levels and riding purposes, therefore improving sample selection in experimental studies. A total of 986 cyclists completed an online questionnaire between February and October 2016. Two-step cluster analyses were performed to generate distinct groups, and dependent variables of these groups were compared (demographics and characteristics of cycling practice). The cluster analysis relied on 4 descriptors (cycling weekly volume, average cycling speed, riding purpose, and cycling discipline) and yielded five distinct groups: competitive road, recreational road, competitive mountain bike (MTB), recreational MTB and competitive triathlon. Among these groups, averages and distributions for age, height, body mass, body mass index, training volume and intensity, and years of experience varied. This categorization can potentially help researchers recruit specific groups of cyclists based upon self-reported data and therefore better align the sample characteristic with the research aims.


Assuntos
Ciclismo/classificação , Sujeitos da Pesquisa , Antropometria , Análise por Conglomerados , Humanos , Destreza Motora , Projetos de Pesquisa , Estudos Retrospectivos , Viés de Seleção , Autorrelato , Inquéritos e Questionários
2.
J Aging Phys Act ; 24(1): 72-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25880874

RESUMO

A crossover experiment was performed to determine whether age and sex, or their interaction, affect the impact of acute aerobic exercise on vigor-activity (VA). We also tested whether changes in VA mediated exercise effects on performance on various cognitive tasks. Sixty-eight physically inactive volunteers participated in exercise and TV-watching control conditions. They completed the VA subscale of the Profile of Mood States immediately before and 2 min after the intervention in each condition. They also performed the Trail Making Test 3 min after the intervention in each condition. Statistical analyses produced a condition . age . sex interaction characterized by a higher mean VA gain value in the exercise condition (compared with the VA gain value in the TV-watching condition) for young female participants only. In addition, the mediational analyses revealed that changes in VA fully mediated the effects of exercise on TMT-Part A performance.


Assuntos
Afeto/fisiologia , Cognição/fisiologia , Exercício Físico/fisiologia , Adulto , Fatores Etários , Idoso , Estudos Cross-Over , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Fatores Sexuais , Teste de Sequência Alfanumérica
3.
J Sports Sci ; 31(14): 1606-13, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23713547

RESUMO

Aerodynamic and rolling resistances are the two major resistances that affect road cyclists on level ground. Because of reduced speeds and markedly different tyre-ground interactions, rolling resistance could be more influential in mountain biking than road cycling. The aims of this study were to quantify 1) aerodynamic resistance of mountain-bike cyclists in the seated position and 2) rolling resistances of two types of mountain-bike tyre (smooth and knobby) in three field surfaces (road, sand and grass) with two pressure inflations (200 and 400 kPa). Mountain-bike cyclists have an effective frontal area (product of projected frontal area and drag coefficient) of 0.357 ± 0.023 m², with the mean aerodynamic resistance representing 8-35% of the total resistance to cyclists' motion depending on the magnitude of the rolling resistance. The smooth tyre had 21 ± 15% less rolling resistance than the knobby tyre. Field surface and inflation pressure also affected rolling resistance. These results indicate that aerodynamic resistance influences mountain-biking performance, even with lower speeds than road cycling. Rolling resistance is increased in mountain biking by factors such as tyre type, surface condition and inflation pressure that may also alter performance.


Assuntos
Desempenho Atlético , Ciclismo , Fenômenos Físicos , Adolescente , Adulto , Humanos , Masculino , Equipamentos Esportivos , Propriedades de Superfície , Adulto Jovem
4.
J Appl Biomech ; 28(6): 636-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22694978

RESUMO

This study was designed to examine the biomechanical and physiological responses between cycling on the Axiom stationary ergometer (Axiom, Elite, Fontaniva, Italy) vs. field conditions for both uphill and level ground cycling. Nine cyclists performed cycling bouts in the laboratory on an Axiom stationary ergometer and on their personal road bikes in actual road cycling conditions in the field with three pedaling cadences during uphill and level cycling. Gross efficiency and cycling economy were lower (-10%) for the Axiom stationary ergometer compared with the field. The preferred pedaling cadence was higher for the Axiom stationary ergometer conditions compared with the field conditions only for uphill cycling. Our data suggests that simulated cycling using the Axiom stationary ergometer differs from actual cycling in the field. These results should be taken into account notably for improving the precision of the model of cycling performance, and when it is necessary to compare two cycling test conditions (field/laboratory, using different ergometers).


Assuntos
Ciclismo/fisiologia , Ergometria/instrumentação , Ergometria/métodos , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Análise e Desempenho de Tarefas , Adulto , Humanos , Masculino
5.
PLoS One ; 14(1): e0211197, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30682136

RESUMO

Although cycling has been associated with overuse/fatigue and acute injuries, there is lack of information regarding associated risk factors and prevention factors. The objective of the study was to determine the factors associated with injury, and perceptions of discomfort and pain in cyclists. A total of 739 cyclists completed an online questionnaire between February and October 2016. The questionnaire acquired information on participant demographics, characteristics related to cycling profile and fitness training, bike components and cycling posture, self-reported perceptions of comfort and pain, and injuries sustained in the last 12 months. Logistic regression models estimated odds ratios (OR) and 95% confidence intervals (95%CI) that examined factors associated with reporting overuse/fatigue injury, acute injury, body discomfort, saddle discomfort, and pain while cycling. Odds of reporting an overuse/fatigue injury increased when the cyclists complemented training with running (OR = 1.74; 95%CI = 1.03-2.91) or swimming (OR = 2.17; 95%CI = 1.19-3.88), and with reported pain while cycling (OR = 1.17; 95%CI = 1.05-3.69) and not cycling (OR = 1.76; 95%CI = 1.07-2.90). Odds of reporting an acute injury increased when biking to work (OR = 1.79; 95%CI = 1.07-2.86), and decreased with increased average cycling speed (1-km/h decrease OR = 0.93; 95%CI = 0.88-0.97), and compared to low-end bike, with the use of mid-range (OR = 0.25; 95%CI = 0.09-0.72) and high-end bike (OR = 0.34; 95%CI = 0.13-0.96). Although body discomfort was only associated with saddle discomfort and the presence of pain during cycling, saddle discomfort was also associated with biking to work (OR = 0.46; 95%CI = 0.22-0.88). Finally, pain perception was associated with a number of factors such as ride to work, core training, cycling experience, saddle discomfort, pain while not cycling. Numerous factors are associated with injury, and perceptions of discomfort and pain in cyclists. Such factors should be considered when developing training routines, bicycle maintenance best practices, and injury prevention programs.


Assuntos
Ciclismo/lesões , Dor/psicologia , Adulto , Ciclismo/psicologia , Estudos Transversais , Europa (Continente) , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Percepção da Dor , Estudos Retrospectivos , Fatores de Risco , Autorrelato , América do Sul , Inquéritos e Questionários
6.
7.
Eur J Sport Sci ; 15(2): 161-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25131146

RESUMO

The present study was performed as an evaluation of the relationships between changes in facial temperature and self-reported pleasure-displeasure during an acute aerobic exercise bout. Ninety-two students performed a 10-minute long session of cycle ergometry at 80-85% of age-predicted maximal heart rate. Using infrared thermography and a single-item measure of pleasure-displeasure (the Feeling Scale, FS), facial temperature and the FS score were sampled at the beginning (Min1:00) and at the end of the exercise session (Min9:00). Statistical analyses revealed that cheek (but not forehead) temperature was higher at the end of the exercise bout compared to Min1:00 (it increased by about 5%). Change in cheek temperature was negatively related to end-exercise affect (ß = -0.28, P < 0.001) and to during-exercise affective changes (ß = -0.35, P < 0.001). No significant relationship with forehead temperature was found. Some of the possible reasons for this differential effect as well as theoretical and practical implications of our findings are discussed.


Assuntos
Afeto , Temperatura Corporal , Exercício Físico , Face , Prazer , Temperatura , Adolescente , Adulto , Ciclismo , Bochecha , Exercício Físico/fisiologia , Exercício Físico/psicologia , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Termografia , Adulto Jovem
8.
Res Q Exerc Sport ; 86(3): 252-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26115364

RESUMO

PURPOSE: Increased core (brain or body) temperature that accompanies exercise has been posited to play an influential role in affective responses to exercise. However, findings in support of this hypothesis have been equivocal, and most of the performed studies have been done in relation to anxiety. The aim of the present study was to investigate the effects of tympanic temperature on basic affect (i.e., pleasure-displeasure) in the course of a high-intensity exercise session. METHOD: One hundred seventy students performed a 10-min cycling exercise at an intensity of 80% to 85% of maximal heart rate. Heart rate, tympanic temperature, and self-reported pleasure (using the Feeling Scale [FS]) were measured twice during exercise at the end of the first minute (Min 1:00) and beginning of the last minute (Min 9:00). RESULTS: Small increases in tympanic temperature were noted from Min 1:00 to Min 9:00 (mean change value = +0.2°C). Meanwhile, the FS scores changed in the opposite direction (mean change value = - 0.2 units). However, changes in temperature only poorly predicted changes in pleasure-displeasure (R(2) = .05 for the linear regression, R(2) = .08 for the curvilinear regression). CONCLUSIONS: Slight elevated tympanic temperature occurred during the 10-min cycling exercise, but it had a negligible effect on changes in pleasure ratings. The possibility that tympanic temperature is not a valid indicator of core temperature during exercise is discussed.


Assuntos
Afeto/fisiologia , Temperatura Corporal , Exercício Físico/fisiologia , Exercício Físico/psicologia , Prazer/fisiologia , Membrana Timpânica/fisiologia , Feminino , Frequência Cardíaca , Humanos , Masculino , Autorrelato , Fatores Sexuais , Adulto Jovem
9.
Acta Bioeng Biomech ; 17(1): 87-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25951821

RESUMO

PURPOSE: The purpose of this study was to investigate the effect of whole body vibration in oxygen uptake during intense squatting exercise with an added weight and whole body vibration compared with the same exercise without vibration. METHODS: Nine male sub- jects performed three trials of dynamic squatting with an additional load of 50% of their body weight during 3 min. One trial without vibration, one trial with the frequency of 40 Hz and amplitude of 2 mm and one trial with the frequency of 40 Hz and amplitude of 4 mm. RESULTS: The results showed no difference between the three experimental trials in relative and absolute oxygen uptake. However, the metabolic power and energy expended in whole body vibration (2 mm) were significantly different from exercise without vibration. The data analysis also showed a significant difference in rating of perceived exertion with whole body vibration (4 mm) compared with the exercise without vibration. Results showed that the addition of vibration stimulus has an increase in the energy expenditure particularly with 40 Hz and 2 mm amplitude, suggesting that the high metabolic power during heavy resistance training could be increased by the addition of vibration stimulation. CONCLUSIONS: Involuntary contractions generated by the vibration can be used by coaches to increase the intensity of heavy resistance training or to increase the energy expended during the workouts if the goal is a decrease of body mass.


Assuntos
Metabolismo Energético , Treinamento Resistido , Adulto , Humanos , Masculino , Contração Muscular , Consumo de Oxigênio , Esforço Físico/fisiologia , Postura/fisiologia , Troca Gasosa Pulmonar , Respiração , Vibração , Adulto Jovem
10.
J Sports Sci ; 27(10): 1059-67, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19847689

RESUMO

In this paper, we examine the hypothesis that telic dominance is one of the psychological variables that may influence the exercise-affect relationship according to the dual-mode model of exercise and affect (Ekkekakis, 2003). Thirty-three participants with high or low telic dominance rated their affect at 3-min intervals as they ran on a treadmill while the speed was adjusted to maintain their respiratory exchange ratio at a target value of 1.00 +/- 0.02 for a period of 10 min. Compared with baseline scores (which were not statistically different between the two groups), the mean decline in pleasure at the end of the run was twofold greater in participants with high telic dominance. This was observed after having controlled for individual differences in aerobic fitness (as measured by [Vdot]O(2max)). We also detected an earlier onset of decreases in pleasure in high telic dominant participants. Our data extend the burgeoning research on variables influencing one's ability to continue exercising at an imposed intensity that can produce pain or discomfort (i.e. tolerance of exercise intensity). Additionally, results from this study support continued promotion of tailor-made prescriptions for maximizing positive affective outcomes during exercise, which ultimately may lead to increased adherence to an exercise programme.


Assuntos
Afeto , Inventário de Personalidade , Corrida/fisiologia , Corrida/psicologia , Adolescente , Adulto , Análise de Variância , Teste de Esforço , Feminino , Humanos , Masculino , Fatores de Tempo
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