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1.
J Hum Kinet ; 90: 161-168, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38380310

RESUMEN

The aim of the present study was to analyze the sporting progression from U14 to senior categories of elite Spanish high and long jumpers. For prospective analysis, 300 athletes ranked top 20 at U14 were analyzed (153 female and 147 male). For retrospective analysis, 64 athletes ranked in the top 20 in the senior category were included (21 female and 43 male). Ranking positions were registered in each of the seasons where they presented records. Only 6.3% (19) of athletes who reached the top 20 at U14 became successful senior athletes [4.7% (14) of athletes maintained top 20 status throughout their sporting careers from U14 to senior]. The transition rate from U14 to U16 (35.7%) was the most severe drop down in consecutive categories (after this, it ranged from 47.8 to 66.7%). Of the senior top 20 athletes (64), most of them were already ranked top 20 at U16 (59.4%, 38), at U18 (62.5%, 40), at U20 (70.3%, 45) and at U23 (78.1%, 50). Nevertheless, only 34.4% (22) were top 20 when they were U14 athletes. Transition rates in the top 20 senior athletes ranged from 86.7 to 95.5%. Around one out of four (26.6%, 17) of the top 20 senior athletes maintained top 20 status throughout their sporting careers from U14 to the senior category. Although early success is not a good predictor of senior success, successful senior athletes excelled early on and were able to remain in top rankings throughout their sporting careers of national elite jumpers.

2.
Nutrients ; 16(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38276565

RESUMEN

This study aimed to analyze the placebo effect associated with caffeine ingestion on running performance. METHODS: Thirteen recreationally trained males in long-distance running (age: 38.5 ± 11.9 years, 11.0 ± 8.8 years of running experience) performed a 6 min time trial test in each experimental condition (caffeine-informed/placebo ingested (placebo) and non-ingested (control)) separated by 7 days. The total distance covered was measured, and partial times of each 400 m were used to analyze the pacing strategy. Heart rate and kinematic variables were recorded for each split. In addition, the rate of perceived exertion and prevalence of caffeine side effects was measured using questionnaires. RESULTS: Placebo ingestion improved running performance in the 6 min time trial test (1668 ± 139 m placebo vs. 1642 ± 158 m control, t = 2.49; p = 0.03; moderate ES = 0.69), while pacing, heart rate, RPE, and kinematic variables were similar between conditions (p > 0.05 in all cases). Minor side effects were reported. CONCLUSIONS: Beliefs of caffeine ingestion can improve running performance at speeds around maximal aerobic speed in recreationally trained runners without affecting pacing strategy so this "nutritional" strategy could be useful in competition scenarios. As a practical application, recreationally trained runners could improve ≈5 s in 1500 m or mile competitions.


Asunto(s)
Rendimiento Atlético , Carrera , Masculino , Humanos , Adulto , Persona de Mediana Edad , Cafeína/farmacología , Rendimiento Atlético/fisiología , Carrera/fisiología , Frecuencia Cardíaca , Ingestión de Alimentos , Método Doble Ciego
3.
J Hum Kinet ; 89: 139-148, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38053948

RESUMEN

The aim of the study was to describe the relationship between success in junior and senior categories in sprint events. An observational and longitudinal analysis was carried out using rankings of the Royal Spanish Athletics Federation database. We analysed 547 sprinters (238 women and 309 men) from their U14 to senior stage who ranked in top-20 on at least one occasion during the period 2004 to 2021. The first entry in top-20 occurred mostly in U14 (44.4%, 243), and the frequency was progressively lower: 26.7% (146) in U16; 20.8% (114) in U18; 5.1% (28) in U20; 2% (11) in U23; and 0.9% (5) in the senior category. A similar tendency was observed in male and female athletes. Only 3.8% (9) of top-20 U14 athletes reached the senior elite stage, increasing this percentage in subsequent categories: 7.4% (15) in U16; 10.6% (24) in U18; 20.9% (32) in U20, and 31.4% (32) from U23 to the senior category. Data from female athletes showed higher maintenance of top-20 status from early categories to senior age. We conclude that even though the first entry into the national top-20 in sprint events occurs early in most cases, success in these initial stages is not a prerequisite for reaching top-20 positions in the senior category.

4.
Med Sci Sports Exerc ; 55(12): 2290-2298, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37443458

RESUMEN

INTRODUCTION/PURPOSE: Previous results about shoe longitudinal bending stiffness (LBS) and running economy (RE) show high variability. This study aimed to assess the effects of shoes with increased LBS on RE and performance in trained and national runners. METHODS: Twenty-eight male runners were divided into two groups according to their 10-km performance times (trained, 38-45 min and national runners, <34 min). Subjects ran 2 × 3 min (at 9 and 13 km·h -1 for trained, and 13 and 17 km·h -1 for national runners) with an experimental shoe with carbon fiber plate to increase the LBS (Increased LBS) and a control shoe (without carbon fiber plate). We measured energy cost of running (W·kg -1 ) and spatiotemporal parameters in visit one and participants performed a 3000 m time trial (TT) in two successive visits. RESULTS: Increased LBS improved RE in the trained group at slow (11.41 ± 0.93 W·kg -1 vs 11.86 ± 0.93 W·kg -1 ) and fast velocity (15.89 ± 1.24 W·kg -1 vs 16.39 ± 1.24 W·kg -1 ) and only at the fast velocity in the national group (20.35 ± 1.45 W·kg -1 vs 20.78 ± 1.18 W·kg -1 ). The improvements in RE were accompanied by different changes in biomechanical variables between groups. There were a similar improvement in the 3000 m TT test in Increased LBS for trained (639 ± 59 vs 644 ± 61 s in control shoes) and national runners (569 ± 21 vs 574 ± 21 s in control shoes) with more constant pace in increased LBS compared with control shoes in both groups. CONCLUSIONS: Increasing shoe LBS improved RE at slow and fast velocities in trained runners and only at fast velocity in national runners. However, the 3000 m TT test improved similarly in both levels of runners with increased LBS. The improvements in RE are accompanied by small modifications in running kinematics that could explain the difference between the different levels of runners.


Asunto(s)
Carrera , Zapatos , Humanos , Masculino , Fibra de Carbono , Fenómenos Biomecánicos
5.
Nutrients ; 15(5)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36904177

RESUMEN

This overview review aimed to describe the evolution of the characteristics of the research on caffeine effects on strength. A total of 189 experimental studies with 3459 participants were included. The median sample size was 15 participants, with an over-representation of men vs. women (79.4 vs. 20.6%). Studies on young participants and elders were scarce (4.2%). Most studies tested a single dose of caffeine (87.3%), while 72.0% used doses adjusted to body mass. Single-dose studies ranged from 1.7 to 7 mg/kg (4.8 ± 1.4 mg/kg), while dose-response studies ranged from 1 to 12 mg/kg. Caffeine was mixed with other substances in 27.0% of studies, although only 10.1% of studies analyzed the caffeine interaction with these substances. Capsules (51.9%) and beverages (41.3%) were the most common forms of caffeine administration. Similar proportions of studies focused on upper (24.9%) or lower body strength 37.6% (37.6% both). Participants' daily intake of caffeine was reported in 68.3% of studies. Overall, the pattern in the study of caffeine's effects on strength performance has been carried out with experiments including 11-15 adults, using a single and moderate dose of caffeine adjusted to participants' body mass in the form of a capsule.


Asunto(s)
Cafeína , Sustancias para Mejorar el Rendimiento , Masculino , Adulto , Humanos , Femenino , Anciano , Cafeína/farmacología , Resistencia Física , Café , Bebidas , Fuerza Muscular
6.
Nutrients ; 14(21)2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36364784

RESUMEN

In Spain, students pursuing a career in athletic training, physical education, or scientific evaluation of sports enroll in a bachelor's degree in sports sciences. This degree provides knowledge and skills in a broad array of sports settings and promotes research-based interdisciplinary knowledge. However, the student's syllabus rarely includes specific academic training on anti-doping regulations or doping prevention. The purpose of this study was to assess the anti-doping knowledge of the students undertaking a bachelor's degree in sports sciences in Spanish universities. One thousand two hundred and thirty-three bachelor students in sport science (907 males, 322 females, and 4 participants with non-binary sex) from 26 Spanish universities completed a validated questionnaire about general anti-doping knowledge. The questionnaire is an adapted version of the Play True Quiz of the World Anti-Doping Agency and contains 37 multiple-choice questions. The score obtained in the questionnaire was transformed into a 0−100-point scale. The questionnaire was distributed among students within each university by a faculty member and it was filled out online. Students obtained a score of 65.8 ± 10.10 points (range = 32−92 points). There was an effect of the course in the score obtained (p < 0.001). Students of the first course (63.6 ± 9.5 points) had lower scores than the remaining courses (p < 0.037) while the students of the fourth course obtained the highest scores (68.7 ± 9.5 points; p < 0.019). The students with an itinerary on sports performance were the respondents with the highest anti-doping knowledge (67.2 ± 10.2) points, followed by the students with an itinerary on health (66.7 ± 9.5 points). The knowledge of basic anti-doping rules and doping prevention strategies of the bachelor students in sports sciences in Spain was suboptimal. Increasing doping prevention information in the syllabus of the bachelor's degree in sports sciences is essential as these future professionals will directly work with populations at risk of doping.


Asunto(s)
Medicina Deportiva , Deportes , Masculino , Femenino , Humanos , España , Estudiantes , Universidades , Encuestas y Cuestionarios
7.
J Int Soc Sports Nutr ; 19(1): 366-380, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35813843

RESUMEN

The aim of this investigation was to determine the effect of a moderate dose of caffeine (3 mg/kg/b.m.) on muscular power and strength and shot put performance in trained athletes. METHODS: Thirteen shot putters (eight men and five women) participated in a double-blind, placebo-controlled, randomized experiment. In two different trials, participants ingested either 3 mg/kg/b.m. of caffeine or a placebo. Forty-five min after substance ingestion, athletes performed a handgrip dynamometry test, a countermovement jump (CMJ), a squat jump (SJ), and a maximum-velocity push-up. The athletes also performed three types of throws: a backwards throw, a standing shot put and a complete shot put. RESULTS: In comparison with the placebo, caffeine ingestion increased CMJ height (32.25 ± 7.26 vs. 33.83 ± 7.72 cm, respectively; effect size (ES) = 0.82, p = 0.012; +5.0%;) and SJ height (29.93 ± 7.88 vs. 31.40 ± 7.16 cm; ES = 0.63, p = 0.042; +6.4%) and distance in the standing shot put (10.27 ± 1.77 m vs. 10.55 ± 1.94 m; ES = 0.87, p = 0.009; +2.6%). However, caffeine ingestion did not increase strength in the handgrip test, power in the ballistic push-up, or distance in the backwards throw (all p > 0.05). Shot put performance changed from 11.24 ± 2.54 to 11.35 ± . 2.57 m (ES = 0.33, p = 0.26; +1.0%), although the difference did not reach statistically significant differences. Caffeine ingestion did not increase the prevalence of side effects (nervousness, gastrointestinal problems, activeness, irritability, muscular pain, headache, and diuresis) in comparison with the placebo (p > 0.05). CONCLUSION: In summary, caffeine ingestion with a dose equivalent to 3 mg/kg/b.m. elicited moderate improvements in several aspects of physical performance in trained shot putters but with a small effect on distance in a complete shot put.


Asunto(s)
Rendimiento Atlético , Cafeína , Atletas , Cafeína/farmacología , Suplementos Dietéticos , Método Doble Ciego , Femenino , Fuerza de la Mano , Humanos , Masculino , Fuerza Muscular
8.
Bioanalysis ; 13(19): 1467-1476, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34617450

RESUMEN

We aimed to analyze the number and distribution of doping control tests in which a banned substance was reported (i.e., adverse analytical finding) in aquatics. The analysis was performed by using the data provided by the WADA Testing Figure Reports from 2015 to 2019. A total of 79,956 doping control tests were analyzed. Sprint swimming, middle-distance swimming and water polo were the disciplines with the highest number of doping control tests. However, there were no differences in the frequency of adverse findings among disciplines (overall, ∼0.56%, from 0.13 in artistic swimming to 0.76% in sprint swimming). Sprinters and long-distance swimmers presented a higher frequency of beta-2-agonists than the remaining aquatic disciplines (p < 0.05). These results indicate that the type of prohibited substances employed is strongly influenced by the intrinsic characteristics of each aquatic discipline.


Asunto(s)
Doping en los Deportes
9.
Arch Osteoporos ; 16(1): 83, 2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-34080075

RESUMEN

This investigation presents a comparison of calcaneus bone stiffness of endurance runners of different ages and age-matched controls. We found that there was an age-associated decline in calcaneus bone stiffness in the control group while endurance runners prevented this decline, with a higher effect as the participants increased their age. PURPOSE: Previous investigations have found that endurance runners have higher bone mineral density and other bone quality variables in mechanically loaded bones. However, it is unknown if endurance running might counteract the decline in bone stiffness that occurs with age. The purpose of this study was to compare calcaneus bone stiffness of endurance runners of different ages to age-matched controls. METHODS: In a descriptive cross-sectional study, 182 endurance-trained male runners and 116 healthy untrained male controls underwent an ultrasonographic assessment of the calcaneus bone in the right and left heels. Calcaneal bone stiffness was calculated from assessments of the broadband ultrasound attenuation and the speed of sound. RESULTS: The line of best fit for the association between age and calcaneus stiffness was different between marathoners and controls (Z = - 2.1, P = 0.02). A two-way ANCOVA (condition × age) with body mass, and body mass index as covariates, revealed that there were main effects of condition (F = 26.8, P < 0.01) and age (F = 4.2, P < 0.01) for calcaneus stiffness, with a significant interaction between these two factors (F = 2.8, P = 0.03). The post hoc analysis revealed that calcaneus stiffness was significantly higher in marathoners of 40-44 years (121.5 ± 18.2 vs 101.1 ± 21.3 arbitrary units [A.U.], P = 0.01), 45-49 years (121.5 ± 19.7 vs 104.3 ± 13.4 A.U., P = 0.04), and > 50 years (111.2 ± 17.9 vs 92.4 ± 16.0 A.U., P < 0.01) than their untrained counterparts of the same age with no statistically significant differences in the remaining age groups. CONCLUSION: Endurance runners of > 40 years had higher values of calcaneus stiffness than controls, providing evidence to support the potential effect of endurance running to reduce the age-related decline on calcaneus bone stiffness.


Asunto(s)
Calcáneo , Entrenamiento Aeróbico , Carrera , Densidad Ósea , Calcáneo/diagnóstico por imagen , Estudios Transversales , Humanos , Masculino , Ultrasonografía
10.
Eur J Nutr ; 60(7): 4107-4114, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33606090

RESUMEN

PURPOSE: Caffeine is widely considered an ergogenic aid to increase anaerobic performance although most of this evidence is supported by investigations with only male samples. To date, it is unknown if the ergogenic effect of caffeine on anaerobic performance is of similar magnitude in men and women athletes. The aim of this study was to determine the magnitude of the ergogenic effect of caffeine on the Wingate test in men and women. METHODS: In a double-blind, placebo-controlled, cross-over experimental trial, ten women athletes and ten men athletes performed a 15-s adapted version of the Wingate test after ingesting 3 mg of caffeine per kg of body mass or a placebo (cellulose). RESULTS: In comparison to the performance obtained in the 15-s Wingate test with a placebo, caffeine increased peak power in men (9.9 ± 0.8 vs. 10.1 ± 0.8 W/kg, p < 0.01, d = 0.26) and in women (8.8 ± 0.9 vs. 9.1 ± 0.8 W/kg, p = 0.04, d = 0.30). Caffeine was also effective to increase the mean power in men (8.9 ± 0.7 vs. 9.0 ± 0.7 W/kg, p = 0.01, d = 0.21) and women (8.1 ± 0.7 vs. 8.3 ± 0.7 W/kg, p = 0.01, d = 0.27). The ergogenic effect of caffeine on the 15-s Wingate peak power (2.3 ± 3.2% in men and 3.2 ± 2.8% in women; p = 0.46) and mean power (2.0 ± 1.7% and 2.4 ± 2.3%, respectively; p = 0.93) was of similar magnitude in both sexes. CONCLUSION: Acute ingestion of 3 mg kg-1 of caffeine enhanced peak and mean cycling power during a 15-s adapted version of the Wingate test in men and women and the ergogenic effect was of similar magnitude in both sexes. This information suggests that both men and women athletes might obtain similar benefits from caffeine supplementation during anaerobic exercise.


Asunto(s)
Rendimiento Atlético , Sustancias para Mejorar el Rendimiento , Anaerobiosis , Atletas , Cafeína/farmacología , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino
11.
Front Nutr ; 8: 622564, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33575270

RESUMEN

Previous research has identified acute caffeine intake as an effective ergogenic aid to enhance velocity and power during bench press exercise. However, no previous investigation has analyzed the effects of chronic intake of caffeine on training adaptations induced by bench press strength training. Thus, the aim of this investigation was to determine the effects of pre-exercise caffeine intake on training adaptations induced by a bench press training protocol. Using a double-blind, randomized experimental design, 16 healthy participants underwent a bench press training protocol for 4 weeks (12 sessions). Seven participants ingested a placebo and nine participants ingested 3 mg/kg/BM of caffeine before each training session. Three days before, and 3 days after the completion of the training protocol, participants performed a one-repetition maximum (1RM) bench press and force-velocity test (from 10 to 100% 1RM). From comparable pre-training values, the strength training similarly increased 1RM in the caffeine and placebo groups (+13.5 ± 7.8% vs. +11.3 ± 5.3%, respectively; p = 0.53). In the caffeine group, the strength training induced a higher mean velocity at 40%, (0.81 ± 0.08 vs. 0.90 ± 0.14 m/s), 60% (0.60 ± 0.06 vs. 0.65 ± 0.06 m/s), 70% (0.47 ± 0.05 vs. 0.55 ± 0.06 m/s), 80% (0.37 ± 0.06 vs. 0.45 ± 0.05 m/s), 90% (0.26 ± 0.07 vs. 0.34 ± 0.06 m/s), and 100% 1RM (0.14 ± 0.04 vs. 0.25 ± 0.05 m/s; p < 0.05) while the increases in the placebo group were evident only at 30 (0.95 ± 0.06 vs. 1.03 ± 0.07 m/s), 70% (0.51 ± 0.03 vs. 0.57 ± 0.05 m/s) and 80% 1RM (0.37 ± 0.06 vs. 0.45 ± 0.05 m/s) (p < 0.05). The placebo group only increased peak velocity at 60 and 70% 1RM (p < 0.05) while peak velocity increased at 10%, and from 30 to 100% 1RM in the caffeine group (p < 0.05). The use of 3 mg/kg/BM of caffeine before exercise did not modify improvements in 1RM obtained during a 4 week bench press strength training program but induced more muscle performance adaptations over a wider range of load.

12.
Bioanalysis ; 13(1): 5-11, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33326303

RESUMEN

The aim of this investigation was to describe the outcomes of the adverse analytical findings in different Olympic sports. The data included were gathered from the World Anti-Doping Agency Anti-doping Rule Violations Reports (2013-2017). Weightlifting (78.1 ± 9.4%) wrestling (73.2 ± 18.5%) and volleyball (68.3 ± 18.7%) were the sports with the highest proportion of cases that ended in an antidoping sanction. Gymnastics (45.1 ± 10.1%), triathlon (32.6 ± 11.9%) and shooting (29.9 ± 14.1%) were the sports with a higher frequency of cases that were not sanctioned due to medical reasons. Gymnastics (22.4 ± 18.4%), boxing (23.2 ± 16.0%) and taekwondo (17.3.1 ± 16.4%) presented the highest proportion of cases that are still pending resolution. The proportion of cases that ended in no sanction was higher in fencing (26.2 ± 22.7%), skating (23.6 ± 35.1%) and tennis (18.6 ± 26.5%). These results indicate that the sanctions derived from antidoping rule violations were not uniform in all sports disciplines.


Asunto(s)
Deportes de Equipo , Femenino , Humanos , Masculino , Resultado del Tratamiento
13.
J Hum Kinet ; 74: 185-193, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33312286

RESUMEN

Previous investigations have established the ergogenic effect of caffeine on maximal muscle strength, power output and strength-endurance. However, these investigations used testing protocols that do not replicate the structure of a regular strength training session. Thus, the aim of this study was to investigate the effect of acute caffeine ingestion on muscle performance during a simulated velocity-based training workout. In a double-blind, randomized and counterbalanced experiment, 12 participants performed two experimental trials after ingesting 3 mg/kg/b.m. of caffeine or a placebo. The trials consisted of 4 sets of 8 repetitions of the bench press exercise at 70% of their one-repetition maximum performed at maximal velocity. Bar velocity was recorded with a rotatory encoder and force, power output and work were calculated. Regarding the whole workout, caffeine increased mean bar velocity (+7.8%; p=0.002), peak bar velocity (+8.7%; p=0.006), mean force (+1.5%; p=0.002), mean power output (+10.1%; p=0.003) and peak power output (+8.2%; p=0.004) when compared to the placebo. The total work performed in the caffeine trial was superior to the placebo trial (7.01±2.36 vs 6.55±2.20 kJ, p=0.001). These results suggest that the acute intake of 3 mg/kg/b.m. of caffeine before a velocity-based strength workout increased muscle performance and the total work performed across the whole training session. Thus, caffeine can be considered as an effective strategy to enhance muscle performance during the bench press training sessions.

14.
Rev. bras. med. esporte ; 26(5): 391-395, Sept.-Oct. 2020. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1137931

RESUMEN

ABSTRACT Introduction: This study aimed to measure thickness and cross-sectional area of the Achilles tendon (AT), and the range of motion of the ankle joint in dorsiflexion of amateur marathon runners compared to non-active people. Objectives: To analyze the relationship between cross-sectional area and thickness of the Achilles tendon in marathon runners and age, anthropometric characteristics (height and body mass), training habits, running experience, marathon performance, and range of motion in the ankle joint. Methods: Achilles tendon thickness and cross-sectional area were measured using ultrasound images of the left leg in 97 male amateur marathon runners (age 42.0 ± 9.6 years; height 175 ± 6 cm; and body mass 73.7 ± 8.6 kg), and 47 controls (39.9 ± 11.6 years; 176 ± 7 cm; 79.6 ± 16.1 kg). Results: Achilles tendon thickness (4.81 ± 0.77 vs. 4.60 ± 0.66 mm; p = 0.01) and cross-sectional area (60.41 ± 14.36 vs. 53.62 ± 9.90 mm2; p < 0.01) were greater in the marathon runners than in non-active people. Achilles tendon thickness has been correlated, in a weak but significant manner, with years of running experience. Moreover, marathon runners showed increased ankle range of motion (81.81 ± 6.93 vs. 77.86 ± 7.27 grades; p<0.01). Conclusion: Male amateur marathon runners have hypertrophy of the Achilles tendon compared to non-active people, and this enlargement is mediated by running experience. In addition, range of motion in ankle dorsiflexion is favored by marathon training. Level of evidence III; Retrospective study.


RESUMO Introdução: Este estudo visou medir a espessura e a área transversal do tendão de Aquiles (TA) e a amplitude de movimento da articulação do tornozelo em flexão dorsal em maratonistas amadores, em comparação com indivíduos não ativos. Objetivos: Analisar a relação entre a área transversal e a espessura do tendão de Aquiles em maratonistas e idade, características antropométricas (estatura e massa corporal), hábitos de treinamento, experiência de corrida, desempenho em maratona e amplitude de movimento da articulação do tornozelo. Métodos: A espessura do tendão de Aquiles e a área transversal foram medidas por meio de imagens de ultrassom da perna esquerda em 97 maratonistas amadores do sexo masculino (idade 42,0 ± 9,6 anos; altura 175 ± 6 cm; massa corporal 73,7 ± 8,6 kg) e 47 controles (39,9 ± 11,6 anos; 176 ± 7 cm; 79,6 ± 16,1 kg). Resultados: A espessura (4,81 ± 0,77 vs. 4,60 ± 0,66 mm; p = 0,01) e a secção transversal (60,41 ± 14,36 vs. 53,62 ± 9,90 mm2; p < 0,01) do tendão de Aquiles foram superiores nos maratonistas do que nos indivíduos não ativos. Verificou-se correlação fraca, mas significativa, entre espessura do tendão de Aquiles com os anos de experiência em corrida. Além disso, os maratonistas tiveram aumento da amplitude de movimento da articulação do tornozelo (81,81 ± 6,93 vs. 77,86 ± 7,27 graus; p < 0,01). Conclusão: Os maratonistas amadores do sexo masculino têm hipertrofia do tendão de Aquiles em comparação com indivíduos não ativos e esse aumento é mediado pela experiência em corrida. Além disso, a amplitude de movimento na flexão dorsal da articulação do tornozelo é favorecida pelo treinamento de maratona. Nível de evidência III; Estudo retrospectivo.


RESUMEN Introducción: Este estudio buscó medir el espesor y el área transversal del tendón de Aquiles (TA), y la amplitud de movimiento de la articulación del tobillo en flexión dorsal en maratonianos amateur en comparación con individuos no activos. Objetivos: Analizar la relación entre el área transversal y el grosor del tendón de Aquiles en maratonianos y edad, características antropométricas (estatura y masa corporal), hábitos de entrenamiento, experiencia en carrera, desempeño en maratón y amplitud de movimiento de la articulación del tobillo. Métodos: Fueron medidos el grosor y el área transversal del tendón de Aquiles por medio de imágenes de la pierna izquierda a 97 maratonianos amateur del sexo masculino (edad 42,0 ± 9,6 años; altura 175 ± 6 cm; masa corporal 73,7 ± 8,6 kg), y 47 controles (39,9 ± 11,6 años; 176 ± 7 cm; 79,6 ± 16,1 kg). Resultados: El grosor (4,81 ± 0,77 vs. 4,60 ± 0,66 mm; p = 0,01) y la sección transversal (60,41 ± 14,36 vs. 53,62 ± 9,90 mm2; p < 0.01) fueron superiores en los maratonianos que en los individuos no activos. Se verificó correlación débil, aunque significativa, entre grosor del tendón de Aquiles con los años de experiencia en carrera. Además, los maratonianos tuvieron aumento de la amplitud de movimiento de la articulación del tobillo (81,81 ± 6,93 vs. 77,86 ± 7,27 grados; p<0,01). Conclusión: Los maratonianos amateur del sexo masculino tienen hipertrofia del tendón de Aquiles en comparación con individuos no activos, y ese aumento es mediado por la experiencia en carrera. Además, la amplitud de movimiento en la flexión dorsal de la articulación del tobillo es favorecida por el entrenamiento de maratón. Nivel de evidencia III; Estudio retrospectivo.

15.
Subst Use Misuse ; 55(8): 1361-1369, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32186429

RESUMEN

Background: In recent years, there has been a solid effort across all sports organizations to reduce the prevalence and incidence of doping in sport. However, the efficacy of current strategies to fight against doping might be improved by using anti-doping polices tailored to the features of doping in each sport. Objectives: The aim of this investigation was to analyze the substances more commonly found in doping control tests in individual and team sports. Material and Methods: The publicly accessible Testing Figures Reports made available by the World Anti-Doping Agency, were analyzed from 2014 to 2017. Results: The most commonly detected groups of banned substances were anabolic agents and stimulants but the distribution of adverse findings per drug class was very different depending on the sports discipline. Weightlifting, athletics, rugby, hockey and volleyball presented abnormally high proportions of anabolic agents (p = 2.8 × 10-11). Cycling, athletics and rugby presented atypically elevated proportions of peptide hormones and growth factors (p = 1.4 × 10-1). Diuretics and masking agents were more commonly found in boxing, wrestling, taekwondo, judo, shooting, and gymnastics than in other sports (p = 4.0 × 10-68). Cycling, rowing, aquatics, tennis, gymnastics and ice hockey presented abnormally high proportions of stimulants (p = 1.8 × 10-5). Conclusions: These results indicate that the groups of banned substances more commonly detected in anti-doping control tests were different depending on the sports discipline. These data suggest the prohibited substances used as doping agents might be substantially different depending on the type of sport and thus, sports-specific anti-doping policies should be implemented to enhance the efficacy of anti-doping testing.


Asunto(s)
Anabolizantes , Doping en los Deportes , Detección de Abuso de Sustancias , Fútbol Americano , Humanos , Preparaciones Farmacéuticas , Deportes de Equipo
16.
Eur J Nutr ; 59(7): 3293-3302, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31900579

RESUMEN

PURPOSE: This study aimed to identify and describe the time course of tolerance to the most common caffeine-induced side effects. METHODS: Eleven participants took part in a crossover, double-blind placebo-controlled experimental design. In one phase, participants ingested 3 mg/kg/day of caffeine for 20 days, while in another phase, they ingested a placebo. Resting heart rate and blood pressure were measured three times per week during each 20-day phase and a quantitative survey was used to categorise the magnitude of side effects. RESULTS: In the pairwise comparison with the placebo, the ingestion of caffeine increased systolic (+ 7.8 ± 10.1%, P < 0.05) and diastolic blood pressure (+ 6.4 ± 12.9% P < 0.05) for the first 8 days of ingestion, but then this effect became attenuated for both outcomes (on day 20, - 1.1 ± 4.3% and + 0.9 ± 9.6%, respectively). The ingestion of caffeine did not affect heart rate at any time point. Caffeine increased the feelings of nervousness and vigour and the rating of gastrointestinal complaints, insomnia and diuresis at several time points in the treatment (P < 0.05) and they did not disappear after 20 days of ingestion. CONCLUSIONS: The daily intake of 3 mg/kg of caffeine induced a meaningful elevation in arterial blood pressure that disappeared after 8 days. However, other caffeine-induced effects such as increased nervousness and vigour, irritability, insomnia and diuresis remained after 20 days of consecutive caffeine ingestion. Although there was clear tolerance to the effect of caffeine on blood pressure, the persistence of other side effects suggests the inconvenience of maintaining a chronic caffeine intake, at least at the dose of 3 mg/kg/day.


Asunto(s)
Cafeína/administración & dosificación , Cafeína/efectos adversos , Adulto , Presión Sanguínea/efectos de los fármacos , Estudios Cruzados , Método Doble Ciego , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Factores de Tiempo
19.
Nutrients ; 11(4)2019 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-30934886

RESUMEN

The ergogenicity of caffeine on several exercise and sport situations is well-established. However, the extent of the ergogenic response to acute caffeine ingestion might greatly vary among individuals despite using the same dosage and timing. The existence of one or several individuals that obtained minimal ergogenic effects or even slightly ergolytic effects after caffeine intake (i.e., non-responders) has been reported in several previous investigations. Nevertheless, the concept non-responding to caffeine, in terms of physical performance, relies on investigations based on the measurement of one performance variable obtained once. Recently it has been suggested that correct identification of the individual ergogenic effect induced by caffeine intake requires the repeated measurement of physical performance in identical caffeine⁻placebo comparisons. In this communication, we present data from an investigation where the ergogenic effect of acute caffeine intake (3 mg/kg) was measured eight times over a placebo in the same individuals and under the same conditions by an incremental cycling test to volitional fatigue and an adapted version of the Wingate cycling test. The ergogenic response to caffeine varied from 9% to 1% among individuals, but all participants increased both cycling power in the incremental test and Wingate mean power at least three to eight times out of eight the caffeine⁻placebo comparisons. These data expand the suggestion of a minimal occurrence of caffeine non-responders because it shows that all individuals responded to caffeine when caffeine is compared to a placebo on multiple and repeated testing sessions.


Asunto(s)
Cafeína/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Resistencia Física/efectos de los fármacos , Esfuerzo Físico/efectos de los fármacos , Adulto , Estudios Cruzados , Fatiga , Humanos
20.
Nutrients ; 11(2)2019 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-30699902

RESUMEN

The ergogenic effect of caffeine is well-established, but the extent of its consumption in sport is unknown at the present. The use of caffeine was considered "prohibited" until 2004, but this stimulant was moved from the List of Prohibited Substances to the Monitoring Program of the World Anti-Doping Agency to control its use by monitoring urinary caffeine concentration after competition. However, there is no updated information about the change in the use of caffeine as the result of its inclusion in the Monitoring Program. The aim of this study was to describe the changes in urine caffeine concentration from 2004 to 2015. A total of 7488 urine samples obtained in official competitions held in Spain and corresponding to athletes competing in Olympic sports (2788 in 2004, 2543 in 2008, and 2157 in 2015) were analyzed for urine caffeine concentration. The percentage of samples with detectable caffeine (i.e., >0.1 µg/mL) increased from ~70.1%, in 2004⁻2008 to 75.7% in 2015. The median urine caffeine concentration in 2015 (0.85 µg/mL) was higher when compared to the median value obtained in 2004 (0.70 µg/mL; p < 0.05) and in 2008 (0.70 µg/mL; p < 0.05). The urine caffeine concentration significantly increased from 2004 to 2015 in aquatics, athletics, boxing, judo, football, weightlifting, and rowing (p < 0.05). However, the sports with the highest urine caffeine concentration in 2015 were cycling, athletics, and rowing. In summary, the concentration of caffeine in the urine samples obtained after competition in Olympic sports in Spain increased from 2004 to 2015, particularly in some disciplines. These data indicate that the use of caffeine has slightly increased since its removal from the list of banned substances, but urine caffeine concentrations suggest that the use of caffeine is moderate in most sport specialties. Athletes of individual sports or athletes of sports with an aerobic-like nature are more prone to using caffeine in competition.


Asunto(s)
Cafeína/orina , Estimulantes del Sistema Nervioso Central/farmacología , Doping en los Deportes , Sustancias para Mejorar el Rendimiento/orina , Deportes , Femenino , Humanos , Masculino
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