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1.
Phys Ther Sport ; 65: 122-129, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38159445

RESUMO

BACKGROUND/OBJECTIVE: The purpose of this study was to compare finger flexor strength (FS), finger flexor muscle recovery (FR), and forearm circumference (FC) across three different climbing classes in male lead sport climbers. METHODS: A total of 37 male lead sport climbers were classified into low (LC), intermediate (IC), and advanced classes (AC) categories according to the International Rock Climbing Research Association (IRCRA) Scale. All participants measured FS three times for both open grip (OG) and crimp grip (CG). Following FS measurement, the FR was observed immediately after the all-out training. The FC was measured twice using an inelastic tape. RESULTS: The FS differed significantly across climbing classes for both grip styles and hands, regardless of dominant hand, with the higher classes showing greater FS (all, p ≤ 0.001). FR was significantly higher in AC compared to IC and LC at 5 min (all, p ≤ 0.001), 10 min (all, p ≤ 0.005) and 15 min (all, p ≤ 0.005). The FC showed significant differences with climbing classes for both forearms. CONCLUSION: Climbing classes are associated with differences in FS, with higher class corresponding to greater FS. Similarly, climbing classes are linked to FR and FC, with higher classes being associated with faster recovery and larger FC.


Assuntos
Montanhismo , Esportes , Humanos , Masculino , Montanhismo/fisiologia , Esportes/fisiologia , Dedos/fisiologia , Músculo Esquelético/fisiologia , Antebraço/fisiologia , Força da Mão/fisiologia
2.
Int J Biometeorol ; 68(2): 351-366, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38114844

RESUMO

The majority of research dealing with the impacts of the Himalayan climate on human physiology focuses on low air temperature, high wind speed, and low air pressure and oxygen content, potentially leading to hypothermia and hypoxia. Only a few studies describe the influence of the weather conditions in the Himalayas on the body's ability to maintain thermal balance. The aim of the present research is to trace the heat exchange between humans and their surroundings during a typical, 6-day summit attempt of Mount Everest in the spring and winter seasons. Additionally, an emergency night outdoors without tent protection is considered. Daily variation of the heat balance components were calculated by the MENEX_HA model using meteorological data collected at automatic weather stations installed during a National Geographic expedition in 2019-2020. The data represent the hourly values of the measured meteorological parameters. The research shows that in spite of extreme environmental conditions in the sub-summit zone of Mount Everest during the spring weather window, it is possible to keep heat equilibrium of the climbers' body. This can be achieved by the use of appropriate clothing and by regulating activity level. In winter, extreme environmental conditions in the sub-summit zone make it impossible to maintain heat equilibrium and lead to hypothermia. The emergency night in the sub-peak zone leads to gradual cooling of the body which in winter can cause severe hypothermia of the climber's body. At altitudes < 7000 m, climbers should consider using clothing that allows variation of insulation and active regulation of their fit around the body.


Assuntos
Hipotermia , Montanhismo , Humanos , Montanhismo/fisiologia , Estações do Ano , Hipotermia/etiologia , Temperatura Alta , Altitude
3.
PeerJ ; 11: e15886, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780381

RESUMO

This study explored the capabilities of sport climbers to pull up with arms. The methodology aimed at assessing (i) concentric capabilities of arm muscles, (ii) body coordination skills (iii) characteristics of energy storage and (iv) capabilities to resist fatigue. Twenty-eight climbers were tested and the force exerted was recorded during three pull-up exercises: jump tests (with or without coordination, or preceded by an eccentric phase), incrementally weighted pull-ups and maximum number of pull-ups. Force, velocity, muscle power and muscle work were analysed using ANOVA with post-hoc tests and principal component analysis. Correlations with climbing level were also studied. Overall, jump test results showed that body coordination and stretch-shortening cycle phenomena contributed significantly to performance but only the body coordination was related to the climber's grade level. Muscle work and maximum number of pull-ups are correlated with climbing level which showed that the capacity to resist fatigue is another crucial capability of climbers arms. The development of force capacities appeared crucial for performing whereas the velocity capabilities seemed to originate from the climber's own characteristics/style without correlating with climbing performance. Our study provides the basis for evaluating these parameters in order to help trainers in the diagnosis process and training follow-up.


Assuntos
Montanhismo , Esportes , Montanhismo/fisiologia , Esportes/fisiologia , Extremidade Superior/fisiologia , Braço/fisiologia
4.
Sensors (Basel) ; 23(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37299807

RESUMO

Rock climbing has evolved from a method for alpine mountaineering into a popular recreational activity and competitive sport. Advances in safety equipment and the rapid growth of indoor climbing facilities has enabled climbers to focus on the physical and technical movements needed to elevate performance. Through improved training methods, climbers can now achieve ascents of extreme difficulty. A critical aspect to further improve performance is the ability to continuously measure body movement and physiologic responses while ascending the climbing wall. However, traditional measurement devices (e.g., dynamometer) limit data collection during climbing. Advances in wearable and non-invasive sensor technologies have enabled new applications for climbing. This paper presents an overview and critical analysis of the scientific literature on sensors used during climbing. We focus on the several highlighted sensors with the ability to provide continuous measurements during climbing. These selected sensors consist of five main types (body movement, respiration, heart activity, eye gazing, skeletal muscle characterization) that demonstrate their capabilities and potential climbing applications. This review will facilitate the selection of these types of sensors in support of climbing training and strategies.


Assuntos
Montanhismo , Esportes , Dispositivos Eletrônicos Vestíveis , Montanhismo/fisiologia , Músculo Esquelético/fisiologia , Coleta de Dados
5.
J Sports Med Phys Fitness ; 63(7): 819-827, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37154536

RESUMO

BACKGROUND: Forearm muscle strength and endurance are essential determinants of sports climbing success. This study aimed to investigate whether delayed rates of muscle oxygen saturation and total hemoglobin correlate to sustained contraction performance of youth climbers. METHODS: Twelve recreational and competitive youth sport climbers (six females, six males) participated in the study. Variables included finger flexors muscle maximal voluntary contraction, sustained contraction test (SCT), muscle oxygen dynamics (SmO2), and blood volume (tHb) parameters. Pearson's correlation coefficients were calculated to determine the correlation between physiological and performance variables. RESULTS: SCT had a significant positive relationship to SmO2 delayed rate (r=0.728, P=0.007), and a significant negative relationship to tHb delayed rate (r=-0.690, P=0.013). SmO2 delayed rate and tHb delayed rate also had a significant negative correlation (r=-0.760, P=0.004). CONCLUSIONS: According to the results of this study, it can be suggested that delayed rates of SmO2 and tHb could be used in determining and predicting sustainable finger flexors performance in youth climbers. However, future studies investigating delayed rates of SmO2 and tHb in climbers of different ability levels are warranted to investigate this issue in more detail.


Assuntos
Montanhismo , Esportes Juvenis , Masculino , Feminino , Humanos , Adolescente , Antebraço/fisiologia , Força da Mão/fisiologia , Resistência Física/fisiologia , Músculo Esquelético/fisiologia , Contração Muscular/fisiologia , Volume Sanguíneo , Montanhismo/fisiologia
6.
J Strength Cond Res ; 37(6): 1339-1348, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36930882

RESUMO

ABSTRACT: Ginszt, M, Saito, M, Zieba, E, Majcher, P, and Kikuchi, N. Body composition, anthropometric parameters, and strength-endurance characteristics of sport climbers: a systematic review. J Strength Cond Res 37(6): 1339-1348, 2023-Sport climbing was selected to be part of the Summer Olympic Games in Tokyo 2021 with 3 subdisciplines: lead climbing, speed climbing, and bouldering. The nature of physical effort while speed climbing, lead climbing, and bouldering performance is different. This literature review aimed to describe differences between body composition, anthropometric parameters, and upper-limb strength-endurance variables between sport climbers with different ability levels and nonclimbers. The following databases were searched: PubMed and Scopus. The following keywords were used: "sport climbing," "rock climbing," "lead climbing," and "bouldering." Articles were considered from January 2000 to October 2021 if they concerned at least one of the following parameters: body composition (mass, body mass index, body fat, lean muscle mass, bone mineral density), anthropometric parameters (height, ape index), muscle strength (MVC finger strength in half-crimp grip, MVC finger strength to body mass, handgrip strength), and muscle endurance (force time integral, pull-ups). A review shows that body mass and body fat content were lower in the sport climbers compared with controls and in elite sport climbers compared with those less advanced. Sport climbers presented higher values of MVC finger strength in half-crimp grip, MVC finger strength to body mass, handgrip strength, and force time integral parameter than control subjects. Significantly higher MVC values in half-crimp grip were observed in elite sport climbers than in advanced athletes. None of the analyzed work showed differences between sport climber groups in the ape index. The abovementioned parameters may be a key factor in elite sport climbing performance.


Assuntos
Hominidae , Montanhismo , Esportes , Humanos , Animais , Força da Mão/fisiologia , Montanhismo/fisiologia , Esportes/fisiologia , Composição Corporal , Dedos/fisiologia
7.
Scand J Med Sci Sports ; 33(8): 1360-1372, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36920047

RESUMO

The aim of the present cross-sectional study was to determine if chronic rock climbing and climbing-specific resistance training (RT) would modify the reticulospinal tract (RST) efficacy. Sixteen healthy, elite level climbers (CL; n = 16, 5 F; 29.8 ± 6.7 years) with 12 ± 7 years of climbing and climbing-specific RT experience and 15 healthy recreationally active participants (CON; n = 15, 4 F; 24.6 ± 5.9 years), volunteered for the study. We quantified RST efficacy by comparing the effects of a startle stimulus over reaction time (Rtime ) and measured rate of force development (RFD) and surface electromyography (sEMG) in representative muscles during powerful hand grip contractions. Both groups performed two Rtime tasks while performing rapid, powerful gripping with the right hand (Task 1) or during 3-s-long maximal voluntary right hand grip contractions in response to an imperative visual signal alone (V), or combined with a auditory-non startle stimulus (A) or/and startling auditory stimulus (S). We also tested the reproducibility of these responses on two separate days in CON. Intersession reliability ranged from 0.34 to 0.96 for all variables. The CL versus CON was 37% stronger (p = 0.003). The S stimulus decreased Rtime and increased RFD and sEMG in both groups during both tasks (all p < 0.001). Rtime was similar between groups in all conditions. However, CL had a greater RFD from 50 to 100 ms compared with CON only after the S stimulus in both tasks (p < 0.05, d = 0.85-0.96). The data tentatively suggest that chronic rock climbing and climbing-specific RT might improve RST efficacy, by increasing RST input to the α-motoneurons.


Assuntos
Força da Mão , Montanhismo , Humanos , Reprodutibilidade dos Testes , Força da Mão/fisiologia , Músculo Esquelético/fisiologia , Dedos/fisiologia , Estudos Transversais , Montanhismo/fisiologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-36833880

RESUMO

This report aims to summarise the scientific knowledge around hydration, nutrition, and metabolism at high altitudes and to transfer it into the practical context of extreme altitude alpinism, which, as far as we know, has never been considered before in the literature. Maintaining energy balance during alpine expeditions is difficult for several reasons and requires a deep understanding of human physiology and the biological basis for altitude acclimation. However, in these harsh conditions it is difficult to reconcile our current scientific knowledge in sports nutrition or even for mountaineering to high-altitude alpinism: extreme hypoxia, cold, and the logistical difficulties intrinsic to these kinds of expeditions are not considered in the current literature. Requirements for the different stages of an expedition vary dramatically with increasing altitude, so recommendations must differentiate whether the alpinist is at base camp, at high-altitude camps, or attempting the summit. This paper highlights nutritional recommendations regarding prioritising carbohydrates as a source of energy and trying to maintain a protein balance with a practical contextualisation in the extreme altitude environment in the different stages of an alpine expedition. More research is needed regarding specific macro and micronutrient requirements as well as the adequacy of nutritional supplementations at high altitudes.


Assuntos
Doença da Altitude , Montanhismo , Humanos , Altitude , Montanhismo/fisiologia , Hipóxia , Aclimatação/fisiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-35564444

RESUMO

Meaningful, positive, emotional and challenging adventurous activities may generate personal growth or recovery from ill health or injury. In this study, we used a distinctive longitudinal and immersive research approach to explore the psychological impact of a high-altitude expedition to the Nepalese Himalaya on 10 (9 males) UK military veterans with longstanding well-being concerns. In the 12 months prior to the expedition, participants took part in three training weekends in the UK mountains. During the expedition, instructors-who were all experienced health coaches-facilitated reflective practices with the beneficiaries throughout, focusing on experiential transfer to day-to-day lives after the expedition. Follow-up interviews, conducted up to 18-months post-expedition, identified that the most desirable changes aligned with the three innate psychological needs of self-determination theory: autonomy, competence and relatedness. The routines established during the preparation stage and during the expedition itself activated a renewed energy for personal improvement. At 18 months post-expedition, the key changes reflected altered perspective, employment skills and work-life balance, increased physical activity and enhanced personal awareness and mindfulness. Importantly, supported by regular health coaching and focused on the transfer of learning, expeditions can activate meaningful long-term changes to the well-being and personal development of military veterans.


Assuntos
Expedições , Montanhismo , Veteranos , Altitude , Humanos , Masculino , Montanhismo/fisiologia , Reino Unido
10.
J Strength Cond Res ; 36(3): 832-837, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35180193

RESUMO

ABSTRACT: Smetanka, RG, Armenta, RF, Nessler, JA, and Newcomer, SC. Heart rate response, duration, grip strength, and anthropometric characteristics in recreational indoor rock climbers. J Strength Cond Res 36(3): 832-837, 2022-Despite the growing popularity of recreational indoor rock climbing, there is a lack of research on cardiovascular responses to rock climbing. In addition, although the importance of body composition and grip strength has been established in elite climbers, their effect on recreational climbing is unknown. Therefore, the purpose of this study was to characterize the physiological and anthropometric characteristics of indoor climbers engaging in climbing at a recreational or noncompetitive setting. We hypothesized that heart rates and climbing durations would meet the standards set by the American College of Sports Medicine (ACSM) and Center for Disease Control and Prevention (CDC) for eliciting health benefits and that grip strength would decrease over the course of a typical climbing session. One hundred twenty-one male and female adult recreational climbers participated in this study. Following informed consent, subjects were instrumented with a heart rate monitor (Polar V800) which recorded heart rate and duration. Preclimb and postclimb grip strength were evaluated using a hand grip dynamometer and used to calculate fatigue. Subjects were 30.9 ± 8.3 years old and had participated in climbing for 5.6 ± 6.5 years. The average heart rate during climbing sessions was 122.3 ± 14.5 b·min-1, and session duration was 90.6 ± 31.3 minutes. Mean grip strength was 49.9 ± 11.2 kg, whereas the strength to mass ratio was 0.71 ± 0.14, and fatigue was 13.1 ± 11.6%. Results from the current study suggest that recreational indoor climbing elicits exercise heart rates and durations that are consistent with the CDC and ACSM's recommendations for cardiovascular health. Grip strength data suggested that forearm muscle fatigue may limit climbing durations.


Assuntos
Montanhismo , Esportes , Adulto , Antropometria , Feminino , Força da Mão/fisiologia , Frequência Cardíaca , Humanos , Masculino , Montanhismo/fisiologia , Resistência Física/fisiologia , Esportes/fisiologia , Adulto Jovem
11.
Eur J Appl Physiol ; 122(3): 635-649, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34993575

RESUMO

PURPOSE: The combined effects of acute hypoxia and exercise on cognition remain to be clarified. We investigated the effect of speed climbing to high altitude on reactivity and inhibitory control in elite climbers. METHODS: Eleven elite climbers performed a speed ascent of the Mont-Blanc (4810 m) and were evaluated pre- (at 1000 m) and immediately post-ascent (at 3835 m). In both conditions, a Simon task was done at rest (single-task session, ST) and during a low-intensity exercise (dual-task session, DT). Prefrontal cortex (PFC) oxygenation and middle cerebral artery velocity (MCAv) were monitored using near-infrared spectroscopy and transcranial Doppler, respectively, during the cognitive task. Self-perceived mental fatigue and difficulty to perform the cognitive tests were estimated using a visual analog scale. Heart rate and pulse oxygenation (SpO2) were monitored during the speed ascent. RESULTS: Elite climbers performed an intense (~ 50% of the time ≥ 80% of maximal heart rate) and prolonged (8h58 ± 6 min) exercise in hypoxia (minimal SpO2 at 4810 m: 78 ± 4%). Reaction time and accuracy during the Simon task were similar pre- and post-ascent (374 ± 28 ms vs. 385 ± 39 ms and 6 ± 4% vs. 5 ± 4%, respectively; p > 0.05), despite a reported higher mental fatigue and difficulty to perform the Simon task post-ascent (all p < 0.05). The magnitude of the Simon effect was unaltered (p > 0.05), suggesting a preserved cognitive control post-ascent. Pattern of PFC oxygenation and MCAv differed between pre- and post-ascent as well as between ST and DT conditions. CONCLUSIONS: Cognitive control is not altered in elite climbers after a speed ascent to high-altitude despite substantial cerebral deoxygenation and fatigue perception.


Assuntos
Altitude , Cognição/fisiologia , Montanhismo/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo , Circulação Cerebrovascular , Fadiga , Feminino , França , Frequência Cardíaca/fisiologia , Humanos , Hipóxia , Masculino , Consumo de Oxigênio/fisiologia , Tempo de Reação/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Análise e Desempenho de Tarefas
12.
J Sports Sci Med ; 20(3): 438-447, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34267583

RESUMO

This study examined the effects of two or four weekly campus board training sessions among highly accomplished lead climbers. Sixteen advanced-to-elite climbers were randomly allocated to two (TG2), or four weekly campus board training sessions (TG4), or a control group (CG). All groups continued their normal climbing routines. Pre- and post-intervention measures included bouldering performance, maximal isometric pull-up strength using a shallow rung and a large hold (jug), and maximal reach and moves to failure. Rate of force development (RFD; absolute and 100ms) was calculated in the rung condition. TG4 improved maximal force in the jug condition (effect size (ES) = 0.40, p = 0.043), and absolute RFD more than CG (ES = 2.92, p = 0.025), whereas TG2 improved bouldering performance (ES = 2.59, p = 0.016) and maximal moves to failure on the campus board more than CG (ES = 1.65, p = 0.008). No differences between the training groups were found (p = 0.107-1.000). When merging the training groups, the training improved strength in the rung condition (ES = 0.87, p = 0.002), bouldering performance (ES = 2.37, p = 0.006), maximal reach (ES = 1.66, p = 0.006) and moves to failure (ES = 1.43, p = 0.040) more than CG. In conclusion, a five-week campus board training-block is sufficient for improving climbing-specific attributes among advanced-to-elite climbers. Sessions should be divided over four days to improve RFD or divided over two days to improve bouldering performance, compared to regular climbing training.


Assuntos
Desempenho Atlético/fisiologia , Montanhismo/fisiologia , Condicionamento Físico Humano/métodos , Adulto , Braço/anatomia & histologia , Braço/fisiologia , Dedos/fisiologia , Força da Mão , Humanos , Masculino , Fadiga Muscular/fisiologia , Força Muscular , Fatores de Tempo
13.
J Sports Sci Med ; 20(2): 250-257, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34211317

RESUMO

Competitive ski mountaineering (SKIMO) has achieved great popularity within the past years. However, knowledge about the predictors of performance and physiological response to SKIMO racing is limited. Therefore, 21 male SKIMO athletes split into two performance groups (elite: VO2max 71.2 ± 6.8 ml· min-1· kg-1 vs. sub-elite: 62.5 ± 4.7 ml· min-1· kg-1) were tested and analysed during a vertical SKIMO race simulation (523 m elevation gain) and in a laboratory SKIMO specific ramp test. In both cases, oxygen consumption (VO2), heart rate (HR), blood lactate and cycle characteristics were measured. During the race simulation, the elite athletes were approximately 5 min faster compared with the sub-elite (27:15 ± 1:16 min; 32:31 ± 2:13 min; p < 0.001). VO2 was higher for elite athletes during the race simulation (p = 0.046) and in the laboratory test at ventilatory threshold 2 (p = 0.005) and at maximum VO2 (p = 0.003). Laboratory maximum power output is displayed as treadmill speed and was higher for elite than sub-elite athletes (7.4 ± 0.3 km h-1; 6.6 ± 0.3 km h-1; p < 0.001). Lactate values were higher in the laboratory maximum ramp test than in the race simulation (p < 0.001). Pearson's correlation coefficient between race time and performance parameters was highest for velocity and VO2 related parameters during the laboratory test (r > 0.6). Elite athletes showed their superiority in the race simulation as well as during the maximum ramp test. While HR analysis revealed a similar strain to both cohorts in both tests, the superiority can be explainable by higher VO2 and power output. To further push the performance of SKIMO athletes, the development of named factors like power output at maximum and ventilatory threshold 2 seems crucial.


Assuntos
Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Montanhismo/fisiologia , Esqui/fisiologia , Adulto , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Consumo de Oxigênio , Aptidão Física , Análise e Desempenho de Tarefas
14.
Sci Rep ; 11(1): 13530, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34188125

RESUMO

Improving climbing performance strongly depends upon effective training methods. Hangboard training is one of the most popular approaches to increase finger and forearm strength. Training protocols are based on maximizing weight or minimizing edges. We aimed to evaluate which of these protocols was superior. We prospectively analyzed 30 intermediate to advanced climbing athletes [Union Internationale des Associations d'Alpinisme (UIAA) VI-VIII] and randomized them into three groups: control group C (Control, normal climbing training), hangboard group HE (Hang endurance, grips to hold for a determined time decreased every week), and hangboard group HW (Hang weight, + 1.25 kg weight were added each week to hold for a determined time). As endpoints, we measured the grip strength before and after an 8-week training protocol in seven different pinches. Over the 8-week training period, HW hangboard training significantly improved the climbers' grip strength compared to C [p = 0.032, effect size (ES) 0.36]. Maximizing weight improved the strength in I/II + III, I/II + III + IV and fist significantly. HW was superior compared to C in terms of grip strength improvement in three out of seven pinches and overall grip strength. The overall changes in the HE group did not differ significantly from the C group. An 8-week training protocol with increasing weights (HW) significantly improved overall grip strength more than a regular climbing training without the use of a hangboard.


Assuntos
Força da Mão/fisiologia , Montanhismo/fisiologia , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Adulto , Feminino , Humanos , Masculino
15.
Scand J Med Sci Sports ; 31(10): 1941-1948, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34170580

RESUMO

OBJECTIVES: Only a small proportion of lung transplant recipients achieve a physical status comparable to healthy individuals in the long term. It is reasonable to hypothesize that the necessary cardiopulmonary adaptation required for strenuous physical exercise may be impaired. Exposure to high altitude provides an optimal platform to study the physiological cardiopulmonary adaptation in lung transplant recipients under aerobic conditions. To gain a deeper understanding, 14 healthy lung transplant recipients and healthcare professionals climbed the highest peak in North Africa (Mount Jebel Toubkal; 4167 m) in September 2019. METHODS: Monitoring included daily assessment of vital signs, repeated transthoracic echocardiography, pulmonary function tests, and capillary blood sampling throughout the expedition. RESULTS: Eleven out of fourteen lung transplant recipients reached the summit. All recipients showed a stable lung function and vital parameters and physiological adaptation of blood gases. Similar results were found in healthy controls. Lung transplant recipients showed worse results in the 6-minute walk test at low and high altitude compared to controls (day 1: 662 m vs. 725 m, p < 0.001, day 5: 656 m vs. 700 m, p = 0.033) and a lack of contractile adaptation of right ventricular function with increasing altitude as measured by tricuspid plane systolic excursion on echocardiography (day 2: 22 mm vs. 24 mm, p = 0.202, day 5: 23 mm vs. 26 mm, p = 0.035). CONCLUSIONS: Strenuous exercise in healthy lung transplant recipients is safe. However, the poorer cardiopulmonary performance in the 6-minute walk test and the lack of right ventricular cardiac adaptation may indicate underlying autonomic dysregulation.


Assuntos
Altitude , Aptidão Cardiorrespiratória/fisiologia , Transplante de Pulmão , Montanhismo/fisiologia , Transplantados , Sinais Vitais/fisiologia , Adulto , Idoso , Ecocardiografia , Feminino , Coração/diagnóstico por imagem , Coração/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Teste de Caminhada
16.
Nutr. hosp ; 38(2): 321-327, mar.-abr. 2021. tab
Artigo em Espanhol | IBECS | ID: ibc-201876

RESUMO

INTRODUCCIÓN: durante los últimos 20 años se ha producido un incremento en el número de pruebas de deportes de resistencia, así como en el de participantes en las mismas. Un plan nutricional adecuado es esencial para la realización satisfactoria de este tipo de pruebas, tanto en deportistas profesionales como en amateurs. OBJETIVOS: el objetivo de este trabajo fue determinar, evaluar y comparar con las recomendaciones científicas actuales el consumo de carbohidratos, agua y sodio por parte de los participantes de una prueba de carrera de montaña. METODOLOGÍA: la competición realizada por los deportistas fue el "Medio Trail de Alcoy 2019" (Alcoy, España), con un recorrido de 30 km. Tras la realización de la prueba, los participantes rellenaron un cuestionario sobre el consumo de alimentos y bebidas realizado durante la misma, además de contestar a otras preguntas sobre hábitos nutricionales en general. En el estudio se incluyeron 11 participantes que cumplían los criterios de inclusión. RESULTADOS: el resultado obtenido para la ingesta media de carbohidratos fue de 14,93 g/h, para la de sodio de 146,42 mg/h y para la de agua de 399,73 mL/h. El 27 % de los participantes acudía al dietista-nutricionista de manera habitual y ninguno de ellos reportó problemas del tracto gastrointestinal durante la prueba. CONCLUSIONES: el consumo de carbohidratos y de sodio realizado por los participantes fue bajo con respecto a las recomendaciones científicas actuales; no obstante, el consumo de agua fue adecuado conforme a las mismas. Se aconseja a los deportistas de resistencia acudir a un dietista-nutricionista especializado para alcanzar un rendimiento óptimo en las competiciones


INTRODUCTION: there has been an increase in the number of endurance sports events during the last 20 years, as well as in the number of their participants. An adequate nutritional plan is essential for a satisfactory performance in this type of events, both in professional and amateur athletes. OBJECTIVES: the objective was to determine, evaluate, and compare with the current scientific recommendations the consumption of carbohydrates, water, and sodium by participants in a trail-running event. METHODS: the competition completed by the athletes was the "Medio Trail de Alcoy 2019" (Alcoy, Spain), with a distance of 30 km. After completing the race, participants filled out a questionnaire about their food and drink consumption during the event, in addition to other questions about their nutritional habits in general. Eleven participants who met the inclusion criteria were included in the study. RESULTS: the result obtained for average carbohydrate intake was 14.93 g/h, for sodium intake was 146.42 mg/h, and for water intake was 399.73 mL/h. In all, 27 % of participants visited a dietitian-nutritionist on a regular basis, and none reported gastrointestinal tract issues during the race. CONCLUSIONS: the carbohydrate and sodium consumption of participants was low as compared to current scientific recommendations; however, water consumption was adequate according to them. Our advice for endurance athletes is visit a specialized dietitian-nutritionist to achieve optimal performance in competitions


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Montanhismo/fisiologia , Esforço Físico/fisiologia , Água/administração & dosagem , Sódio/administração & dosagem , Carboidratos/administração & dosagem , Inquéritos e Questionários , 24457 , Estudos Transversais , Carboidratos da Dieta/administração & dosagem
17.
Adv Exp Med Biol ; 1335: 111-119, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33742419

RESUMO

Altitude exposure affects hormonal homeostasis, but the adaptation of different populations is still not finely defined. This study aims to compare the mid-term effects of combining physical activity and altitude hypoxia on hormonal profiles in foreign trekkers coming from Italy versus indigenous Nepalese porters during a Himalayan trek. Participants (6 Italians and 6 Nepalese) completed a 300 km distance in 19 days of an accumulated altitude difference of 16,000 m, with an average daily walk of 6 h. The effect of high altitude on hormonal pathways was assessed by collecting blood samples the day before the expedition and the day after its completion. Foreign trekkers had an additional follow-up sample collected after 10 days. The findings revealed a different adaptation of thyroidal and gonadal axes to mid-term strenuous physical activity combined with high-altitude hypobaric hypoxia. The thyroid function shifted to the protective mechanism of low free triiodothyronine (FT3), whereas the gonadal axis was suppressed. The Italian trekkers and Nepalese porters had lower total testosterone and 17-ß-estradiol levels after the expedition. At the follow-up, the Italians had increased testosterone values. Prolactin secretion decreased in the Italians but increased in the Nepalese. We conclude that exposure to high-altitude affects the hormonal axes. The effect seems notably pronounced for the hypothalamus-pituitary gonadal axis, suppressed after high-altitude exposure.


Assuntos
Doença da Altitude , Estradiol/sangue , Exercício Físico , Montanhismo , Testosterona/sangue , Tri-Iodotironina/sangue , Altitude , Expedições , Humanos , Sistema Hipotálamo-Hipofisário , Itália , Montanhismo/fisiologia , Nepal
18.
Int J Sports Physiol Perform ; 16(9): 1242-1252, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33652414

RESUMO

PURPOSE: To examine the validity and reliability of a battery of 10 measures designed to assess the key physiological parameters for successful rock climbing performance. METHODS: In phase 1 of the research, an expert panel, using the Delphi method, established a 10-item test battery based on the key determinants of climbing performance. In phase 2, the tests were assessed for validity and reliability to examine their suitability as sport-specific measures of rock climbing performance. A total of 132 rock climbers, from 7 countries, volunteered to take part in the study. Each climber visited their nearest laboratory on 3 separate occasions in order to enable the required tests and retests to be completed. A minimum of 7 days was allowed between visits. RESULTS: The 10 tests established for phase 2 were designed as sport-specific measures of flexibility, strength, power, and endurance. Results indicated that, while reliable, the flexibility and strength tests were only partially successful in differentiating across climber abilities. The power and endurance tests, however, performed well with regard to validity and reliability, with the finger hang and powerslap tests being most strongly correlated with performance ability (P < .0005 to P < .002). CONCLUSION: The authors' data suggest that climbing may require a threshold level of flexibility and strength for successful performance, beyond which further improvements may not be required. In contrast, the finger hang and powerslap tests were not only reliable measures but also differentiated between climber abilities from lower grade to elite levels.


Assuntos
Montanhismo , Esportes , Força da Mão/fisiologia , Humanos , Montanhismo/fisiologia , Resistência Física/fisiologia , Reprodutibilidade dos Testes , Esportes/fisiologia
19.
Eur J Appl Physiol ; 121(5): 1337-1348, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33591426

RESUMO

PURPOSE: Sport climbing requires high-intensity finger flexor contractions, along with a substantial whole-body systemic oxygen uptake ([Formula: see text]O2) contribution. Although fatigue is often localised to the finger flexors, the role of systemic ̇[Formula: see text]O2 and local aerobic mechanisms in climbing performance remains unclear. As such, the primary purpose of this study was to determine systemic and local muscle oxygen responses during both isolated finger flexion and incremental exhaustive whole-body climbing tests. The secondary aim was to determine the relationship of isolated and whole-body climbing endurance tests to climbing ability. METHODS: Twenty-two male sport climbers completed a series of isometric sustained and intermittent forearm flexor contractions, and an exhaustive climbing test with progressive steepening of the wall angle on a motorised climbing ergometer. Systemic [Formula: see text]O2 and flexor digitorum profundus oxygen saturation (StO2) were recorded using portable metabolic analyser and near-infra red spectroscopy, respectively. RESULTS: Muscle oxygenation breakpoint (MOB) was identifiable during an incremental exhaustive climbing test with progressive increases in angle (82 ± 8% and 88 ± 8% [Formula: see text]O2 and heart rate climbing peak). The peak angle from whole-body treadwall test and impulse from isolated hangboard endurance tests were interrelated (R2 = 0.58-0.64). Peak climbing angle together with mean [Formula: see text]O2 and StO2 from submaximal climbing explained 83% of variance in self-reported climbing ability. CONCLUSIONS: Both systemic and muscle oxygen kinetics determine climbing-specific endurance. Exhaustive climbing and isolated finger flexion endurance tests are interrelated and suitable to assess climbing-specific endurance. An exhaustive climbing test with progressive wall angle allows determination of the MOB.


Assuntos
Dedos/fisiologia , Força da Mão/fisiologia , Montanhismo/fisiologia , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Adulto , Humanos , Masculino , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Consumo de Oxigênio/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho
20.
Nutrients ; 13(2)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573243

RESUMO

High-altitude exposure leads to many physiological challenges, such as weight loss and dehydration. However, little attention has been posed to the role of nutrition and ethnic differences. Aiming to fulfill this gap, five Italian trekkers and seven Nepalese porters, all males, recorded their diet in diaries during a Himalayan expedition (19 days), and the average daily intake of micro and macro-nutrients were calculated. Bioimpedance analysis was performed five times during the trek; muscle ultrasound was performed before and after the expedition, only for the Italians. The Nepalese group consumed a lot of rice and only Italians consumed cheese. Water intake was slightly over 3000 g/d for both groups. Nepalese diet had a higher density of dietary fibre and lower density of riboflavin, vitamins A, K, and B12. Intake of calcium was lower than recommended levels. Body mass index, waist circumference, fat-free mass, and total body water decreased in both groups, whereas resistance (Rz) increased. Italians reactance (Xc) increased at day 9, whereas that of Nepalese occurred at days 5, 9, and 16. The cross-sectional area of the Vastus lateralis was reduced after the expedition. Specific nutritional and food-related risk factors guidance is needed for diverse expedition groups. Loss of muscle mass and balance of fluids both deserve a particular focus as concerns altitude expeditions.


Assuntos
Composição Corporal , Montanhismo/fisiologia , Estado Nutricional , Adulto , Altitude , Composição Corporal/fisiologia , Índice de Massa Corporal , Água Corporal/fisiologia , Ingestão de Líquidos/fisiologia , Ingestão de Alimentos/fisiologia , Ingestão de Energia/fisiologia , Humanos , Itália/etnologia , Masculino , Pessoa de Meia-Idade , Nepal , Estado Nutricional/fisiologia , Circunferência da Cintura
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