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1.
J Sports Med Phys Fitness ; 63(3): 430-435, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35816141

RESUMO

INTRODUCTION: Sitting volleyball is a widely practiced paralympic sport. A correct and standardized physical evaluation helps coaches to plan and manage the training. It is also important to evaluate physical fitness accurately and adopt standardized protocols to compare and normalize the data. The aim of the study was to evaluate physical fitness evaluation methods adopted in sitting volleyball and to eventually propose standard operating procedures. EVIDENCE ACQUISITION: English-written and peer-reviewed original articles were included in this review. The population studied was composed only of athletes practicing sitting volleyball. Articles were searched on the electronic databases PubMed, Web of Science, and Scopus using keywords matched with Boolean operators. Two independent investigators collected and screened the studies against the eligibility criteria. Data were analyzed narratively. EVIDENCE SYNTHESIS: Only 7 studies were eligible and included in this review, but a wide testing methodology exists. There are some tests commonly adopted in the studies included and these are the handgrip test, the agility t-test, the speed, and endurance test. These tests with the 2-site skinfold thickness evaluation, the modified push-ups, the shoulder-stretch test, the chest throw test and the simple reaction time task were included in the standard operating procedure. CONCLUSIONS: The literature on the topic is poor and standardization of the testing procedure to evaluate the physical fitness of people practicing SV has been provided.


Assuntos
Voleibol , Humanos , Força da Mão , Postura Sentada , Aptidão Física , Atletas
2.
Artigo em Inglês | MEDLINE | ID: mdl-35805344

RESUMO

BACKGROUND: Research on biomechanics in rowing has mostly focused on the lumbar spine. However, injuries can also affect other body segments. Thus, the aim of this pilot study was to explore any potential variations in the kinematics of the cervical spine during two different stroke rates on the rowing ergometer in young rowers. METHODS: Twelve young rowers of regional or national level were recruited for the study. The experimental protocol consisted of two separate test sessions (i.e., a sequence of 10 consecutive strokes for each test session) at different stroke rates (i.e., 20 and 30 strokes/min) on an indoor rowing ergometer. Kinematics of the cervical spine was assessed using an inertial sensor capable of measuring joint ROM (angle of flexion, angle of extension, total angle of flexion-extension). RESULTS: Although there were no differences in the flexion and total flexion-extension movements between the test sessions, a significant increase in the extension movement was found at the highest stroke rate (p = 0.04, d = 0.66). CONCLUSION: Young rowers showed changes in cervical ROM according to stroke rate. The lower control of the head during the rowing stroke cycle can lead to a higher compensation resulting in an augmented effort, influencing sports performance, and increasing the risk of injury.


Assuntos
Desempenho Atlético , Esportes Aquáticos , Fenômenos Biomecânicos , Vértebras Cervicais , Ergometria , Vértebras Lombares , Projetos Piloto
3.
Front Physiol ; 13: 828710, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35721540

RESUMO

Purpose: The purpose of this study was to look for a new, simple, and fast method of assessing and monitoring indoor race performance and to assess the relationship between 20 s, 60 s, and 2000 m indoor rowing performances of youth rowers to evaluate their anaerobic profile. Methods: For three consecutive days, 17 young able-bodied male rowers (15.8 ± 2.0 years), performed three tests (20 s, 60 s, and 2000 m) on a rowing ergometer. Mean power (W20, W60, and W2000) and 2000 m time (t2000) were considered for the analysis. In addition, 14 athletes (15-18 years) performed a 20 s, 60 s, and 2000 m tests and used this as a control group. To define the anaerobic profile of the athletes, W20 and W60 were normalized as percentages of W2000. Associations between variables were determined by means of the Pearson correlation coefficient (r). Results: Mean power decreased with increasing test duration (W20 = 525.1 ± 113.7 W; W60 = 476.1 ± 91.0 W; W2000=312.9 ± 56.0 W) and negative correlations emerged between t2000 (418.5 ± 23.1 s) and W20 (r = -0.952, p < 0.0001) and W60 (r = -0.930, p < 0.0001). Conclusion: These findings indicate that W20 and W60 are significant predictors of 2000 m rowing ergometer performances. Furthermore, normalized W20 and W60 can be used to evaluate athletes and as a reference for planning anaerobic training sessions, on a rowing ergometer.

4.
Physiol Rep ; 10(9): e15291, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35510312

RESUMO

There is very little about the impact that sports training has on female football referees. Therefore, we determined the effects of a 40-week physical preparation, including a full football season, on plasma testosterone and cortisol concentrations and physical performance in female football referees. Plasma cortisol and testosterone concentrations were assayed together with fitness tests at the beginning of the training period (T0, in September), after 8 weeks from T0 (T1), at the mid of the season (T2, 24 weeks after T0), and at the end of the season (T3, in June, 40 weeks after T0). Plasma cortisol increased during the first period and up to T2 (from 15.4 ± 4.7 to 28.5 ± 3.9 µg/dl; p < 0.001), and then decreased at the end of the season (T3: 16.0 ± 2.4 µg/dl). Plasma testosterone concentration in T0 was 14.2±0.37 µg/dl and increased in T1 (57.1 ± 3.7 µg/dl) and T2 (47 ± 3.7 µg/dl) and then decreased in T3 (33.5 ± 2.8 µg/dl). Resting testosterone levels in women were very low (14,2 ± 0.37 µg/dl) (Figure 3c). Testosterone increased in T1 (57.1 ± 3.7 µg/dl) and T2 (47 ± 3.7 µg/dl) whilst, at the end of the season, its concentration decreased (33.5 ± 2.8 µg/dl) (Figure 3c). Significant improvements were observed in all physical performances during the observed period (ANOVA, p < 0.05). Finally, testosterone and cortisol concentrations significantly (p < 0.0001 for both) correlated with maximal oxygen consumption. In T1, testosterone concentration was also significantly correlated with running speed test (p < 0.001). In conclusion, training induces endocrine changes in order to maintain body homeostasis in women referees. It is important that coaches and sports scientists regularly observe changes in endocrine function induced by training and matches in female referees, because they can help maximize referees' performance and limit cases of overtraining.


Assuntos
Futebol Americano , Corrida , Exercício Físico , Feminino , Humanos , Hidrocortisona , Testosterona
5.
Artigo em Inglês | MEDLINE | ID: mdl-35409635

RESUMO

BACKGROUND: Although a knee valgus position is related to the increase in injury risk in volleyball players, there is a lack of studies on the relationship between knee valgus and vertical jump (VJ) performance. Hence, the aim of this study was to investigate the effects of a postural exercise program on VJ height in young female volleyball players with knee valgus. METHODS: This pilot study included 19 young female volleyball players divided into the following groups: the Valgus Experimental Group (VEG); the Valgus Control Group (VCG); and the Neutral Control Group (NCG). All three groups carried out the same volleyball training program. In addition, only the VEG underwent a 3-month postural exercise program of 30-45 min/session, twice/week. VJ performance was measured through the Sargent test before (T0), at 6 weeks (T1), and at 12 weeks (T2). RESULTS: A significant effect from T0 to T1 (p = 0.0017) and from T0 to T2 (p = 0.0001) was found in the VEG. No significant differences were found over time in the VCG and in the NCG. CONCLUSION: An integrated postural exercise program might lead to a more balanced muscle efficiency inducing athletes to obtain a higher VJ performance.


Assuntos
Voleibol , Exercício Físico/fisiologia , Terapia por Exercício , Feminino , Humanos , Joelho/fisiologia , Força Muscular/fisiologia , Projetos Piloto , Voleibol/fisiologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-35270434

RESUMO

This prospective cohort study aimed to evaluate whether COVID-19 lockdown caused biological, psychological, and/or physical performance variations in footballers. We compared the 2018/2019 and 2019/2020 seasons evaluating the plasma volume, hematological parameters, iron/ferritin, creatine kinase, vitamin D, cortisol, testosterone, and physiological state of players of the Italian football major league (Serie A). Measurements were performed before the preparatory period (T0), at the beginning (T1) and in the middle (T2) of the championship, and in March (T3) and at the end of season (T4). The results showed that in the 2019/2020 season affected by the lockdown, the weight, BMI, and fat mass percentage were higher than in the previous season. Hematocrit, hemoglobin, red blood cells, and ferritin decreased during both seasons, more significantly than in the regular season. During both seasons, creatine kinase increased from T2 whilst iron concentrations decreased in T3. Testosterone increased in both seasons from T0 to T3 and returned to initial levels at T4; cortisol increased in T2 and T3 during the 2018/2019 season but not during the COVID-19 season. Physical performance tests revealed differences associated with lockdown. Thus, although from a medical point of view, none of the evaluated changes between the two seasons were clinically relevant, training at home during lockdown did not allow the players to maintain the jumping power levels typical of a competitive period.


Assuntos
COVID-19 , Futebol Americano , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Humanos , Desempenho Físico Funcional , Estudos Prospectivos , SARS-CoV-2
7.
Artigo em Inglês | MEDLINE | ID: mdl-33810034

RESUMO

High-level young athletes need to face a wide spectrum of stressors on their journey to élite categories. The aims of the present study are (i) to evaluate session rate of perceived exertion (sRPE) at different training impulse (TRIMP) categories and the correlations between these two variables and, (ii) evaluate the correlations between sRPE, fluid loss, and carbohydrate consumption during exercise. Data on Edward's TRIMP, sRPE, body mass loss pre- and post- exercise (∆), and carbohydrate consumption (CHO/h) during exercise have been acquired from eight male junior cyclists during a competitive season. One-way ANOVA and correlation analysis with linear regression have been performed on acquired data. sRPE resulted in a significant difference in the three TRIMP categories (p < 0.001). sRPE resulted in being very largely positively associated with TRIMP values (p < 0.001; R = 0.71). ∆ as well as CHO/h was largely negatively related with sRPE in all TRIMP categories (p < 0.001). The results confirmed the role of fluid balance and carbohydrate consumption on the perception of fatigue and fatigue accumulation dynamics independently from the training load. Young athletes' training load monitoring and nutritional-hydration support represent important aspects in athlete's exercise-induced fatigue management.


Assuntos
Condicionamento Físico Humano , Esforço Físico , Carboidratos , Fadiga , Frequência Cardíaca , Humanos , Masculino , Percepção
8.
Medicine (Baltimore) ; 100(13): e25289, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33787615

RESUMO

INTRODUCTION: Falls are the leading cause of injury-related mortality and morbidity in the elderly. Physical activity plays a key role in the prevention of falls and stimulates postural control. The aim of this study was to compare a general physical activity program for the elderly with a Pilates program to evaluate the effects on balance and on reducing the risk of falling. MATERIALS AND METHODS: Forty-six subjects were enrolled in this study, but only 41 were included in the study. The subjects were divided into 2 groups: Pilates group (P-G) and a group following a nonspecific program of physical activity (Pa-G). Each subject underwent the hand grip test, Berg balance scale test, and posturographic analysis. RESULTS: Spearman correlation coefficient showed correlations between the following parameters: BBS versus hand grip test (r = 0.68); BBS versus ellipse surface area (r = -0.75). There were significant differences between groups after the exercise program: both groups showed an improvement in performance but the P-G recorded significantly better results than the Pa-G. DISCUSSION AND CONCLUSIONS: This study confirmed that physical activity improves both balance and strength. However, our data show that Pilates has a greater effect on these physical abilities than a general physical activity program.


Assuntos
Acidentes por Quedas/prevenção & controle , Técnicas de Exercício e de Movimento/métodos , Modalidades de Fisioterapia , Idoso , Idoso de 80 Anos ou mais , Exercício Físico , Feminino , Avaliação Geriátrica , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Equilíbrio Postural , Avaliação de Programas e Projetos de Saúde
9.
J Hum Kinet ; 75: 77-83, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33312296

RESUMO

Many studies reported various relationships between 2000-m rowing performance and anthropometric as well as metabolic variables, however, little is known about 60-s mean power in elite youth athletes. The aim of this study was to develop different regression models to predict 2000-m rowing indoor performance time (t2000) using anthropometric variables, maximal oxygen uptake (VO2max) and mean power established during a 60-s all-out test (W60) in national elite youth rowers. Fifteen youth male Italian rowers (age: 15.7 ± 2.0 years; body height: 176.0 ± 8.0 cm; body mass: 71.2 ± 10.0 kg) performed an incremental maximal test, a 60-s all-out test and a 2000-m race simulation using a Concept2 rowing ergometer to assess VO2max, W60 and t2000, respectively. The relationships of all variables with t2000 were investigated through Pearson's correlation. Multiple regression analyses were used to verify the best prediction model of 2000-m indoor rowing performance. The reliability of these models was expressed by R2 and the standard error of estimate. The results showed that t2000 was significantly correlated with all the examined variables, except for VO2max/body mass and age, and exhibited the significantly highest relationship with W60 (r = -0.943). The combination of anthropometric, VO2max and W60 variables was found to be the most reliable equation to predict t2000 (R2 = 0.94, SEE = 6.4). W60 measure should be considered when monitoring the rower's capability to perform high-intensity phases, important during the race's fast start and end. Not requiring expensive equipment and long duration, a 60-s all-out test could be considered a valuable tool for predicting 2000-m performance of elite youth rowers.

10.
Heliyon ; 6(7): e04407, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32715121

RESUMO

BACKGROUND: Goalball is a Paralympic sport for visually impaired athletes. Although it is widely practiced, a great variety of tests are adopted to evaluate athletes' physical fitness. Therefore, the objective was to identify the physical fitness tests adopted in this sport to find the common aspects between them and, eventually, to propose a standard operating procedure. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines were adopted. The studies were extracted from PubMed, Web of Science, and Scopus. A selection process by title, abstract, and full-text, according to the inclusion and exclusion criteria, was performed. The results were discussed with narrative synthesis. RESULTS: A total of 7 papers and 222 participants were included. A wide variety of tests were adopted and the Brockport Physical Fitness Test (BPFT) was the only battery included to evaluate general athletes' well-being. CONCLUSIONS: Although few literature exists on Goalball, the BPFT could be the battery for evaluating Goalball athletes though the test battery should be standardized to the characteristics of this sport.

11.
Artigo em Inglês | MEDLINE | ID: mdl-32635579

RESUMO

BACKGROUND: Congenital hypothyroidism (CH) is an endocrine disease with a precocious significant impairment of growth and neuromotor development. Thyroid hormones are essential for central nervous system development, maturation, and myelination. Furthermore, thyroid hormone deficiency affects the function of several systems, including the musculoskeletal system. The disease has a significant incidence in the general population (1:3000-1:2000 newborns in Italy). The aim of the present study was to evaluate any differences in upper and lower limb strength, body sway, and plantar loading distribution in children with CH compared to healthy children. METHODS: In this study, the case group was composed of children with CH (CHG), while the control group included healthy children (CG). Both groups comprised 19 children (CHG: female = 12; CG: female = 9). The maximum isometric handgrip strength and explosive-elastic lower limb strength were assessed with the handgrip test and the Sargent test, respectively. The stabilometric and baropodometric analyses were used to measure the Center of Pressure displacements and the plantar loading distribution between feet, respectively. The differences between groups were analyzed by a univariate analysis of covariance using as covariates weight and height with the significant level set at < 0.05. RESULTS: We found that CHG children were shorter and thinner than CG ones (p < 0.05). No significant difference in the upper and lower limb strength was found between groups. CHG exhibited a significant greater Sway Path Length (p < 0.01) and Ellipse Surface (p < 0.05) than CG. Moreover, CHG displayed an asymmetric plantar loading distribution with a significant lower percentage in the right than in the left foot (p < 0.05). Moreover, a significant lower plantar loading percentage in the right foot of CHG than in the right foot of CG was observed (p < 0.05). CONCLUSIONS: These findings seem to suggest that CH does not affect muscle strength in early treated children. However, these patients show poor postural control ability and asymmetric plantar loading distribution. Increasing the physical activity in these children could improve their body posture.


Assuntos
Hipotireoidismo Congênito/epidemiologia , Força da Mão/fisiologia , Músculo Esquelético/fisiologia , Equilíbrio Postural , Postura/fisiologia , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Humanos , Itália/epidemiologia , Masculino
12.
Eur J Transl Myol ; 28(1): 7051, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29686813

RESUMO

Relationships between heart rate recovery after exercise (HRR, baseline heart rate variability measures (HRV), and time to perform a 10Km running trial (t10Km) were evaluated in "master" athletes of endurance to assess whether the measured indexes may be useful for monitoring the training status of the athletes. Ten "master" athletes of endurance, aged 40-60 years, were recruited. After baseline measures of HRV, the athletes performed a graded maximal test on treadmill and HRR was measured at 1 and 2 minutes from recovery. Subsequently they performed a 10Km running trial and t10Km was related to HRV and HRR indexes. The time to perform a 10Km running trial was significantly correlated with baseline HRV indexes. No correlation was found between t10Km and HRR. Baseline HRV measures, but not HRR, were significantly correlated with the time of performance on 10km running in "master" athletes. The enhanced parasympathetic function at rest appears to be a condition to a better performance on 10km running. HRV can be simple and useful measurements for monitoring the training stratus of athletes and their physical condition in proximity of a competition.

13.
Medicine (Baltimore) ; 97(14): e0244, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29620637

RESUMO

Balance is a complex process that involves multiple sensory integrations. The auditory, visual, and vestibular systems are the main contributors. Hearing loss or hearing impairment may induce inappropriate postural strategies that could affect balance and therefore increase the risk of falling.The aim of this study was to understand whether hearing loss could influence balance, cervical posture, and muscle activation in the cervical region.Thirteen patients (61 ±â€Š13 years; 161.8 ±â€Š11.0 cm; 70.5 ±â€Š15.9 kg) with moderate hearing loss (Right ear -60 ±â€Š21 dB; Left ear -61 ±â€Š24 dB) underwent: an audiometric examination, a postural examination (with open and closed eyes) through a stabilometric platform, a cervical ROM examination through a head accelerometer, and a sternocleidomastoid electromyography (EMG) examination.A linear regression analysis has shown a regression coefficient (R) 0.76 and 0.69 between hearing loss and the posturographic parameters, on the sagittal sway, with open and closed eyes, respectively. The combination of frontal and sagittal sway is able to explain up to 84% of the variance of the audiometric assessment. No differences were found between right and left hemibody between the audiometric, posturographic, cervical ROM parameters, and in EMG amplitude. ROM and EMG parameters have not shown any significant associations with hearing loss, for both right and left head rotation.Hearing loss is associated to increased posturographic measures, especially the sagittal sway, underlining a reduced postural control in people with hearing impairments. No association was found between the heads posture and neck activation with hearing loss. Hearing loss may be associated with an increased risk of falls.


Assuntos
Perda Auditiva/fisiopatologia , Equilíbrio Postural/fisiologia , Postura/fisiologia , Acelerometria/métodos , Idoso , Audiometria/métodos , Estudos Transversais , Eletromiografia/métodos , Feminino , Cabeça/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço/fisiopatologia
14.
J Sports Med Phys Fitness ; 56(4): 491-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25583232

RESUMO

BACKGROUND: The aim of this study was to assess the influence of the autonomic system on the performance of repeated sprints, involving predominantly neuromuscular power, in young soccer players. METHODS: Twelve young soccer players, selected for the Sicilian Regional Football Representative, mean age 15 years, were recruited. Baseline heart rate variability (HRV) was measured and indices of power spectral analysis (LF, HF, and LF/HF ratio) were calculated to evaluate the sympathovagal balance. The athletes performed 10 maximal 6-second cycling sprints (RS), interspersed with 30 seconds of recovery, to measure the peak power output (PP) represented by the highest power value recorded during a 6-second sprint, and the mean peak power output (MPP) represented by the average of all highest power values recorded within a repeated-sprint bout. RESULTS: PP was negatively correlated with LF (ρ=-0.685, P=0.0141) and LF/HF (ρ=-0.709, P=0.0098), and positively correlated with HF (ρ=0.684, P=0.0142). MPP was negatively correlated with LF (ρ=-0.610, P=0.0350) and LF/HF (ρ=-0.606, P=0.0366), and positively correlated with HF (ρ=0.731, P=0.0070). CONCLUSIONS: Our study shows that a baseline parasympathetic predominance in the autonomic nervous system balance is associated with a better neuromuscular contribution to performance, resulting in higher values of PP and MPP during brief repeated maximal cycling sprints. The assessment of baseline HRV before exercise may be useful for to monitor the physical condition of young soccer players and their readiness status to a higher performance.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Frequência Cardíaca/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Futebol/fisiologia , Adolescente , Atletas , Humanos , Masculino , Força Muscular/fisiologia
15.
J Appl Physiol (1985) ; 113(5): 714-8, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22744971

RESUMO

We previously reported that responsiveness to methacholine (Mch) in the absence of deep inspiration (DI) decreased in healthy subjects after a short course of exercise training. We assessed whether a similar beneficial effect of exercise on airway responsiveness could occur in asthmatics. Nine patients (male/female: 3/6; mean age ± SD: 24 ± 2 yr) with mild untreated asthma [forced expiratory volume in 1 s (FEV(1)): 100 ± 7.4% pred; FEV(1)/vital capacity (VC): 90 ± 6.5%] underwent a series of single-dose Mch bronchoprovocations in the absence of DI in the course of a 10-wk training rowing program (6 h/wk of submaximal and maximal exercise), at baseline (week 0), and at week 5 and 10. The single-dose Mch was established as the dose able to induce ≥ 15% reduction in inspiratory vital capacity (IVC) and was administered to each subject at every challenge occasion. Five asthmatics (male/female: 1/4; mean age ± SD: 26 ± 3 yr) with similar baseline lung function (FEV(1): 102 ± 7.0% predicted; FEV(1)/VC: 83 ± 6.0%; P = 0.57 and P = 0.06, respectively) not participating in the exercise training program served as controls. In the trained group, the Mch-induced reduction in IVC from baseline was 22 ± 10% at week 0, 13 ± 11% at week 5 (P = 0.03), and 11 ± 8% at week 10 (P = 0.028). The Mch-induced reduction in FEV(1) did not change with exercise (P = 0.69). The reduction in responsiveness induced by exercise was of the same magnitude of that previously obtained in healthy subjects (50% with respect to pretraining). Conversely, Mch-induced reduction in IVC in controls remained unchanged after 10 wk (%reduction IVC at baseline: 21 ± 20%; after 10 wk: 29 ± 14%; P = 0.28). This study indicates that a short course of physical training is capable of reducing airway responsiveness in mild asthmatics.


Assuntos
Asma/fisiopatologia , Asma/terapia , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Volume Expiratório Forçado/fisiologia , Adulto , Broncoconstritores/farmacologia , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Capacidade Inspiratória/efeitos dos fármacos , Capacidade Inspiratória/fisiologia , Masculino , Cloreto de Metacolina/farmacologia , Espirometria/métodos , Adulto Jovem
16.
J Appl Physiol (1985) ; 109(2): 288-94, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20538849

RESUMO

Airway responsiveness to methacholine (Mch) in the absence of deep inspirations (DIs) is lower in athletes compared with sedentary individuals. In this prospective study, we tested the hypothesis that a training exercise program reduces the bronchoconstrictive effect of Mch. Ten healthy sedentary subjects (M/F: 3/7; mean + or - SD age: 22 + or - 3 yr) entered a 10-wk indoor rowing exercise program on rowing ergometer and underwent Mch bronchoprovocation in the absence of DIs at baseline, at weeks 5 and 10, as well as 4-6 wk after the training program was completed. Exercise-induced changes on airway cells and markers of airway inflammation were also assessed by sputum induction and venous blood samples. Mean power output during the 1,000 m test was 169 + or - 49 W/stroke at baseline, 174 + or - 49 W/stroke at 5 wk, and 200 + or - 60 W/stroke at 10 wk of training (P < 0.05). The median Mch dose used at baseline was 50 mg/ml (range 25-75 mg/ml) and remained constant per study design. At the pretraining evaluation, the percent reduction in the primary outcome, the inspiratory vital capacity (IVC) after inhalation of Mch in the absence of DIs was 31 +/- 13%; at week 5, the Mch-induced reduction in IVC was 22 + or - 19%, P = 0.01, and it further decreased to 15 + or - 11% at week 10 (P = 0.0008). The percent fall in IVC 4-6 wk after the end of training was 15 + or - 11% (P = 0.87 vs. end of training). Changes in airway cells were not associated with changes in airway responsiveness. Our data show that a course of exercise training can attenuate airway responsiveness against Mch inhaled in the absence of DIs in healthy subjects and suggest that a sedentary lifestyle may favor development of airways hyperresponsiveness.


Assuntos
Broncoconstrição , Exercício Físico , Pulmão/fisiologia , Adulto , Hiper-Reatividade Brônquica/etiologia , Hiper-Reatividade Brônquica/fisiopatologia , Testes de Provocação Brônquica , Broncoconstritores , Volume Expiratório Forçado , Capacidade Residual Funcional , Humanos , Mediadores da Inflamação/sangue , Inalação , Interleucina-8/metabolismo , Pulmão/imunologia , Masculino , Cloreto de Metacolina , Força Muscular , Estudos Prospectivos , Volume Residual , Comportamento Sedentário , Espirometria , Escarro/imunologia , Fatores de Tempo , Capacidade Pulmonar Total , Uteroglobina/sangue , Capacidade Vital , Adulto Jovem
17.
Am J Physiol Regul Integr Comp Physiol ; 289(5): R1496-503, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16020520

RESUMO

Marathon runners show increased circulating CD34+ cell counts and postexercise release of interleukin-6 (IL-6), granulocyte-colony stimulating factor (G-CSF) and flt3-ligand (Bonsignore MR, Morici G, Santoro A, Pegano M, Cascio L, Bonnano A, Abate P, Mirabella F, Profita M, Insalaco G, Gioia M, Vignola AM, Majolino I, Testa U, and Hogg JC. J Appl Physiol 93: 1691-1697, 2002). In the present study we hypothesized that supramaximal ("all-out") exercise may acutely affect circulating progenitors and reticulocytes and investigated possible mechanisms involved. Progenitor release was measured by flow cytometry (n = 20) and clonogenic assays (n = 6) in 20 young competitive rowers (13 M, 7 F, age +/- SD: 17.1 +/- 2.1 yr, peak O2 consumption: 56.5 +/- 11.4 ml.min(-1).kg(-1)) at rest and shortly after 1,000 m "all-out." Release of reticulocytes, cortisol, muscle enzymes, neutrophil elastase, and several cytokines/growth factors was measured. Supramaximal exercise doubled circulating CD34+ cells (rest: 7.6 +/- 3.0, all-out: 16.3 +/- 9.1 cells/mul, P < 0.001), and increased immature reticulocyte fractions; AC133+ cells doubled, suggesting release of angiogenetic precursors. Erythrocyte burst forming units and colony forming units for granulocytes-monocytes and all blood series increased postexercise by 3.4-, 5.5-, and 4.8-fold, respectively (P < 0.01 for all). All-out rowing acutely increased plasma cortisol, neutrophil elastase, flt3-ligand, hepatocyte growth factor, VEGF, and transforming growth factor-beta1, and decreased erythropoietin; K-ligand, stromal-derived factor-1, IL-6, and G-CSF were unchanged. Therefore, all-out exercise is a physiological stimulus for progenitor release in athletes. Release of reticulocytes and proangiogenetic cells and mediators suggests tissue hypoxia as possibly involved in progenitor mobilization.


Assuntos
Exercício Físico/fisiologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Resistência Física/fisiologia , Reticulócitos/citologia , Reticulócitos/fisiologia , Adolescente , Adulto , Ensaio de Unidades Formadoras de Colônias , Citocinas/sangue , Eritropoetina/sangue , Feminino , Fator Estimulador de Colônias de Granulócitos/sangue , Granulócitos/fisiologia , Substâncias de Crescimento/sangue , Humanos , Hidrocortisona/sangue , Elastase de Leucócito/sangue , Masculino , Monócitos/fisiologia
18.
Med Sci Sports Exerc ; 36(10): 1723-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15595293

RESUMO

PURPOSES: This study was designed to assess: a) whether rowing affects airway cell composition, and b) the possible relationship between the degree of ventilation during exercise and airway cells. SUBJECTS AND METHODS: In nine young, nonasthmatic competitive rowers (mean age +/- SD: 16.2 +/- 1.0 yr), induced sputum samples were obtained at rest and shortly after an all-out rowing test over 1000 m (mean duration: 200 +/- 14 s), during which ventilatory and metabolic variables were recorded breath-by-breath (Cosmed K4b, Italy). RESULTS: At rest, induced sputum showed prevalence of neutrophils (60%) over macrophages (40%); after exercise, total cell and bronchial epithelial cell (BEC) counts tended to increase. In the last minute of exercise, mean VE was 158.0 +/- 41.5 L x min(-1), and VO2 x kg(-1) 62 +/- 11 mL x min(-1). Exercise VE correlated directly with postexercise total cell (Spearman rho: 0.75, P < 0.05) an dmacrophage (rho: 0.82, P < 0.05) counts. A similar trend was observed for exercise VE and changes in BEC counts from baseline to postexercise (rho: 0.64, P = 0.11). Exercise VE did not correlate with airway neutrophil counts at rest or after exercise. Expression of adhesion molecules by airway neutrophils, macrophages, and eosinophils decreased after the all-out test. CONCLUSION: Similar to endurance athletes, nonasthmatic competitive rowers showed increased neutrophils in induced sputum compared with values found in sedentary subjects. The trend toward increased BEC postexercise possibly reflected the effects of high airflows on airway epithelium. Airway macrophages postexercise were highest in rowers showing tile most intense exercise hyperpnea, suggesting early involvement of these cells during exercise. However, the low expression of adhesion molecules by all airway cell types suggests that intense short-lived exercise may be associated with a blunted response of airway cells in nonasthmatic well-trained rowers.


Assuntos
Exercício Físico/fisiologia , Descanso/fisiologia , Esportes/fisiologia , Escarro/citologia , Adolescente , Albuminas/análise , Brônquios/citologia , Moléculas de Adesão Celular/metabolismo , Contagem de Células , Células Epiteliais/metabolismo , Feminino , Humanos , Elastase de Leucócito/análise , Macrófagos Alveolares/metabolismo , Masculino , Neutrófilos/metabolismo , Consumo de Oxigênio/fisiologia , Troca Gasosa Pulmonar/fisiologia , Escarro/química
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