Polygenic Profile and Exercise-Induced Muscle Damage by a Competitive Half-Ironman.

Del Coso, J, Salinero, JJ, Lara, B, Gallo-Salazar, C, Areces, F, Herrero, D, and Puente, C. Polygenic profile and exercise-induced muscle damage by a competitive half-ironman. J Strength Cond Res 34(5): 1400-1408, 2020-To date, it is still unknown why some individuals develop higher levels of muscle damage than other individuals, despite participating in exercise with comparable levels of physical intensity. The aim of this investigation was to analyze 7 single-nucleotide polymorphisms (SNPs) that are candidates to explain individual variations in the level of muscle damage attained during a half-ironman competition. Using the model of Williams and Folland (2, 1, and 0 points for optimal, intermediate, and suboptimal genotype), we determined the total genotype score from the accumulated combination of 7 SNPs (ACE = 287bp Ins/Del; ACTN3 = p.R577X; creatine kinase, muscle type = NcoI; insulin-like growth factor 2 = C13790G; interleukin-6 = 174G>C; myosin light chain kinase = C37885A; and tumor necrosis factor-α = 308G>A) in 22 experienced triathletes. Before and after the race, a sample of venous blood was obtained to measure serum markers of muscle damage. Two groups of triathletes were established according to their postcompetition serum CK concentration: low CK responders (n = 10; 377 ± 86 U·L) vs. high CK responders (n = 12; 709 ± 136 U·L). At the end of the race, low CK responders had lower serum myoglobin concentrations (384 ± 243 vs. 597 ± 293 ng·ml, p = 0.04). Although the groups were similar in age, anthropometric characteristics, and training habits, total genotype score was higher in low CK responders than in high CK responders (7.7 ± 1.1 vs. 5.5 ± 1.1 point, p < 0.01). A favorable polygenic profile can contribute to reducing the level of muscle damage developed during endurance exercise.

Physiological Demands of Elite Cross-Country Skiing During a Real Competition.

The aim of this study was to assess different physiological variables before and after a 5-km (women) and 10-km (men) cross-country skiing competition to determine potential mechanisms of fatigue. Fourteen elite-level skiers competed in an official cross-country skiing competition using the classical style (9 men and 5 women). Instantaneous skiing velocity was measured during the race by means of 15-Hz global positioning system devices. Before and after the race, a sample of venous blood was obtained to assess changes in blood lactate and serum electrolyte and myoglobin concentrations. Prerace to postrace changes in blood oxygen saturation, forced vital capacity during a spirometry test, jump height during a countermovement jump, and handgrip force were also measured. Mean race speed was 15.8 ± 2.5 and 15.4 ± 1.5 km·h, whereas mean heart rate was 171 ± 6 and 177 ± 3 b·min for men and women, respectively. There were no significant prerace to postrace changes in jump height, handgrip force, and forced vital capacity in men and women. Blood oxygen saturation was reduced from prerace to postrace in men (95.9 ± 2.1% to 93.1 ± 2.3%, p = 0.02) and women (97.8 ± 1.1% to 92.4 ± 2.1%, p < 0.01), whereas blood lactate concentration increased at the end of the race in men (1.4 ± 0.5 to 4.9 ± 2.1 mmol·L, p < 0.01) and women (1.9 ± 0.1 to 6.9 ± 3.2 mmol·L, p < 0.01). After the race, blood markers of muscle damage were at low concentrations, whereas serum electrolytes remained unchanged. Fatigue in 5- and 10-km cross-country skiing competitions was related to a reduced blood oxygen carrying capacity and presumably increased muscle and blood acidosis, whereas the influence of exercise-induced muscle damage on fatigue was minor.

The use of energy drinks in sport: perceived ergogenicity and side effects in male and female athletes.

The use of caffeine containing energy drinks has dramatically increased in the last few years, especially in the sport context because of its reported ergogenic effect. The ingestion of low to moderate doses of caffeinated energy drinks has been associated with adverse side effects such as insomnia or increased nervousness. The aim of the present study was to assess psycho-physiological changes and the prevalence of side effects resulting from the ingestion of 3 mg caffeine/kg body mass in the form of an energy drink. In a double-blind and placebo controlled experimental design, ninety experienced and low-caffeine-consuming athletes (fifty-three male and thirty-seven female) in two different sessions were provided with an energy drink that contained 3 mg/kg of caffeine or the same decaffeinated energy drink (placebo; 0 mg/kg). At 60 min after the ingestion of the energy drink, participants completed a training session. The effects of ingestion of these beverages on psycho-physiological variables during exercise and the rate of adverse side effects were measured using questionnaires. The caffeinated energy drink increased self-perceived muscle power during exercise compared with the placebo beverage (6·41 (sd 1·7) v. 5·66 (sd 1·51); P= 0·001). Moreover, the energy drink produced a higher prevalence of side effects such as insomnia (31·2 v. 10·4 %; P< 0·001), nervousness (13·2 v. 0 %; P= 0·002) and activeness (16·9 v. 3·9 %; P= 0·007) than the placebo energy drink. There were no sex differences in the incidence of side effects (P>0·05). The ingestion of an energy drink with 3 mg/kg of caffeine increased the prevalence of side effects. The presence of these side effects was similar between male and female participants.

Influence of dorsiflexion shoes on jump performance.

The goal of dorsiflexion sports shoes is to increase jumping capacity by means of a lower position of the heel in relation to the forefoot which results in additional stretching of the ankle plantar flexors. The aim of this study was to compare a dorsiflexion sports shoe model with two conventional sports shoe models in a countermovement jump test. The sample consisted of 35 participants who performed a countermovement jump test on a force platform wearing the three models of shoes. There were significant differences in the way force was manifested (P<0.05) in the countermovement jump test, with a decrease in the velocity of the center of gravity and an increase in force at peak power and mean force in the concentric phase. Moreover, peak power was reached earlier with the dorsiflexion sports shoe model. The drop of the center of gravity was increased in CS1 in contrast to the dorsiflexion sports shoe model (P<.05). However, the dorsiflexion sports shoes were not effective for improving either peak power or jump height (P>.05). Although force manifestation and jump kinetics differ between dorsiflexion shoes and conventional sports shoes, jump performance was similar.

Optimization of Sprint Training Among European Coaches: Quality Over Quantity.

PURPOSE: To describe how high-level European sprint coaches (from 100 to 400 m) work to improve important factors associated with the quality of the holistic training process and the quality of the specific training session. METHODS: A descriptive analysis was conducted using questionnaires from 31 European elite sprint coaches (ie, training athletes defined as tiers 3, 4, and 5) who participated voluntarily. RESULTS: The coaches used traditional periodization (45%) with a 10- to 15-day tapering phase (48%) that includes a reduction in volume, maintenance of intensity, and focus on correct technical execution. In the 3 mesophases, coaches prioritized the basic development of strength and sprint work in the first phases of the season and emphasized more sprint-specific work in the competitive phase. Before sessions, adjustments were made based on factors such as psychological (77%), technical (48%), and physical (39%) parameters. In-session load management relies on a combination of objective and subjective measures (55%), in which the dialogue with athletes (65%) was regarded as the main resource. Feedback during and after sessions covers technical (54%), psychological (48%), and physical (35%) aspects. Recovery protocols after sessions mainly involve rest and professional guidance (42%). For performance assessment and testing, coaches utilize countermovement jump (52%), force-velocity profile (45%), and 30-m flying (61%) as main tools. CONCLUSIONS: European sprint coaches demonstrated a comprehensive approach to planning and management, shedding light on the multifaceted nature of their training methodologies and the diverse tools employed for athlete testing and monitoring.

Frequency and type of adverse analytical findings in athletics: Differences among disciplines.

Athletics is a highly diverse sport that contains a set of disciplines grouped into jumps, throws, races of varying distances, and combined events. From a physiological standpoint, the physical capabilities linked to success are quite different among disciplines, with varying involvements of muscle strength, muscle power, and endurance. Thus, the use of banned substances in athletics might be dictated by physical dimensions of each discipline. Thus, the aim of this investigation was to analyse the number and distribution of adverse analytical findings per drug class in athletic disciplines. The data included in this investigation were gathered from the Anti-Doping Testing Figure Report made available by the World Anti-Doping Agency (from 2016 to 2018). Interestingly, there were no differences in the frequency of adverse findings (overall,~0.95%, range from 0.77 to 1.70%) among disciplines despite long distance runners having the highest number of samples analysed per year (~9812 samples/year). Sprinters and throwers presented abnormally high proportions of adverse analytical findings within the group of anabolic agents (p < 0.01); middle- and long-distance runners presented atypically high proportions of findings related to peptide hormones and growth factors (p < 0.01); racewalkers presented atypically high proportions of banned diuretics and masking agents (p = 0.05). These results suggest that the proportion of athletes that are using banned substances is similar among the different disciplines of athletics. However, there are substantial differences in the class of drugs more commonly used in each discipline. This information can be used to effectively enhance anti-doping testing protocols in athletics.

Injuries in Spanish female soccer players.

BACKGROUND: Epidemiologic research to learn the incidence, type, location, and severity of female soccer injuries and the risk factors for sustaining a sport injury is the first step in developing preventive policies. The aim of this study was to analyze the incidence of injuries in the population of female soccer players in Spain. METHODS: The injuries incurred by 25,397 female soccer players were registered by the medical staff of the Spanish Football Federation during 1 season. A standardized medical questionnaire was used to classify the injury according to type, severity, location, and injury mechanism. A total of 2108 injuries was reported with an incidence of 0.083 injuries per player per season. Most injuries were in the lower limbs (74.0%), mainly affecting knee (30.4%) and ankle joints (17.9%). RESULTS: The proportion of injuries derived from contact with another player was higher during matches (33.7%) than during training (11.4%; p < 0.001). Noncontact injuries were classified as severe more frequently than were contact injuries (51.0% vs. 42.6%; p < 0.001). A higher incidence of injury was found in adult soccer players (≥18 years) vs. their counterparts younger than18 years (0.094 vs. 0.072 injuries per player per year, respectively; p < 0.001). There were no differences between age groups in any other injury variable (e.g., type, mechanism, location, or severity; p > 0.05). CONCLUSION: Most female soccer injuries were located at the knee and ankle; the injury mechanism determined the playing time lost; and the player's age did not affect injury characteristics.

A comparison of the physiological demands imposed by competing in a half-marathon vs. a marathon.

BACKGROUND: While there is widespread scientific information about the physiological challenges imposed on elite endurance runners during competitions, the information regarding the amateur population is scarce. The aim of this study was to compare the physical and physiological load imposed by competing in a real half-marathon vs. a marathon race. METHODS: From a larger group of participants, we selected 22 experienced runners who were matched in pairs (11 marathoners and 11 half-marathoners) for age and anthropometric data. Participants completed their respective distances on the same day and circuit while race time was measured by means of chip timing. Sweat samples were obtained during the race using sweat patches. Before and after the race, a sample of venous blood was obtained and jump height was measured during a countermovement jump. Participants also rated their perception of leg muscle pain at the end of the race. RESULTS: Running pace was similar for half-marathoners vs. marathoners (3.3±0.4 vs. 3.1±0.4 m·s-1; P=0.36). At the end of the race, jump height reduction (-11±12% vs. -25±19%; P=0.03), serum myoglobin concentration (186.1±93.6 vs. 564.1±370.7 µg·mL-1; P<0.01) and self-reported muscle pain (3.0 ±2.3 vs. 5.5 ±1.0 A.U.; P<0.01) were lower in half-marathoners vs. marathoners. Sweat rate (~1.0±0.3 L·h-1; P=0.79) and sweat sodium concentration (47.8±29.4 and 39.3±24.1 mmol·L-1; P=0.47) were similar for both groups but body mass reduction (-1.9±0.8% vs. -3.3±0.8%; P<0.01) and electrolyte imbalance were higher in marathoners. CONCLUSIONS: Completing a marathon induces higher muscle fatigue, greater muscle fiber damage and perceived muscle pain levels and higher body water and electrolyte deficits than finishing a half-marathon with a similar running speed. This information could be valuable to improve physical training for endurance running disciplines.

CYP1A2 Genotype Variations Do Not Modify the Benefits and Drawbacks of Caffeine during Exercise: A Pilot Study.

Previous investigations have determined that some individuals have minimal or even ergolytic performance effects after caffeine ingestion. The aim of this study was to analyze the influence of the genetic variations of the CYP1A2 gene on the performance enhancement effects of ingesting a moderate dose of caffeine. In a double-blind randomized experimental design, 21 healthy active participants (29.3 ± 7.7 years) ingested 3 mg of caffeine per kg of body mass or a placebo in testing sessions separated by one week. Performance in the 30 s Wingate test, visual attention, and side effects were evaluated. DNA was obtained from whole blood samples and the CYP1A2 polymorphism was analyzed (rs762551). We obtained two groups: AA homozygotes (n = 5) and C-allele carriers (n = 16). Caffeine ingestion increased peak power (682 ± 140 vs. 667 ± 137 W; p = 0.008) and mean power during the Wingate test (527 ± 111 vs. 518 ± 111 W; p < 0.001) with no differences between AA homozygotes and C-allele carriers (p > 0.05). Reaction times were similar between caffeine and placebo conditions (276 ± 31 vs. 269 ± 71 milliseconds; p = 0.681) with no differences between AA homozygotes and C-allele carriers. However, 31.3% of the C-allele carriers reported increased nervousness after caffeine ingestion, while none of the AA homozygotes perceived this side effect. Genetic variations of the CYP1A2 polymorphism did not affect the ergogenic effects and drawbacks derived from the ingestion of a moderate dose of caffeine.

Predicting race time in male amateur marathon runners.

BACKGROUND: The aim of the study was to analyze the relationship between anthropometry, training characteristics, muscular strength and effort-related cardiovascular response and marathon race time in male amateur runners. METHODS: A total of 84 male amateur marathon runners aged between 23 and 70 years took part in this study (41.0±9.5 years). All of them competed in the 2013 edition of the Madrid Marathon with a finish time between 169.8 and 316 minutes (226.0±28.5 minutes). Age, running experience, number of marathon races finished, mean kilometers run weekly in the last three months, and previous personal best time in the 10 km, half marathon and marathon were recorded. Moreover, anthropometric characteristics, and the results from the Ruffier Test and a whole-body isometric force test were measured. After the marathon, the race time was registered. RESULTS: Training volume (r=-0.479; P=0.001), previous running milestones (marathon r=0.756; half-marathon r=0.812; 10-km r=0.732; P<0.001), cardiovascular fitness (r=0.371; P=0.001) and anthropometric variables (body mass, Body Mass Index, body fat percentage, skinfolds and lower leg volume) were correlated to marathon performance (P<0.05). Two regression models appeared from the data with r2>0.50. The best, including body fat percentage, heart rate change during the recovery after the Ruffier Test and the half-marathon race time, was strongly correlated with real marathon performance (r=0.77; P<0.001). A second regression model was proposed replacing the half-marathon performance with the 10-km race time, reducing the correlation to 0.73 (P<0.001). CONCLUSIONS: Marathon performance could be partially predicted by two different equations, including body fat percentage, recovery heart rate in the Ruffier Test and a half-marathon or 10-km performance.

Respiratory function is associated to marathon race time.

BACKGROUND: The purpose of this study was to analyze the relationship between marathon race time and expiratory pulmonary parameters in a heterogeneous group of amateur marathoners. METHODS: A total of 110 marathon runners (age=41.9±9.4 yr, body mass=74.0±9.1 kg, height=175.0±8.0 cm) volunteered to participate in this study. First, they completed a questionnaire about running experience and best performance time in the 10-km, half-marathon and marathon competitions. Then, they performed a maximal spirometry test following guidelines for standardized spirometry. Measurement included peak expiratory flow (PEF), forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC). All these expiratory variables were normalized for the participant's body mass. Within 3 days of the spirometry test, participants competed in an official marathon and race time was measured by a chip-timing. After this, participants were grouped by their marathon race time as follows: <210 min, N.=33; between 210 and 240 min, N.=31; and >240 min, N.=46). RESULTS: Marathon race time correlated to the FVC·kg-1 (r=-0.41; P<0.001), to FEV1·kg-1 (r=-0.40; P<0.001), and PEF·kg-1 (r=-0.50; P=0.005). However, self-reported running experience did not show significant correlations to FVC·kg-1 and PEF·kg-1 (P>0.05). The group of faster marathoners (e.g., <210 min) had greater FEV1·kg-1 (<210 min group: 0.064±0.009; 210-240 min group: 0.058±0.008; >240 min group: 0.057±0.009; P<0.001) and higher FVC·kg-1 (<210 min group: 0.081±0.011; 210-240 min group: 0.075±0.012; >240 min group: 0.072±0.010; P<0.001) than the other two groups of slower runners. CONCLUSIONS: These results suggest a significant relationship between individual pulmonary function and marathon race time. Thus, a higher lung capacity per kg of body mass might be a key variable for marathon performance in amateur runners.

Upper body injuries and Key Performance Indicators in professional basketball players / Lesiones de la parte superior del cuerpo e indicadores clave de rendimiento en jugadores profesionales de baloncesto

INTRODUCTION: Upper body injuries are less common than lower body injuries in basketball, but there is still a lack of knowledge about the relationship among their occurrence and the performance profile of professional basketball players. This study aimed to analyse the relationships between upper-body injuries and Key Performance Indicators (KPIs) of basketball players. MATERIAL AND METHOD: Statistical variables of 554 professional basketball players (age: 26.97 ± 4.86 years, height: 199.23 ± 8.80 cm, minutes per season: 441.18 ± 301.41) in Spanish ACB (Asociación de Clubes de Baloncesto) professional competition were analysed for two seasons (2012-13 and 2013-14). Besided, injury reports were registered and injuries were categorized with OSICS-10 classification. The players who played the most minutes during the season were more likely to suffer lumbar spine, head, wrist, and hand injuries. The players injured in the thoracic spine obtained a better average in steals per minute. The players injured in the head or the elbow had better +/- performance per minute. The players injured in the neck had better means per minute in received fouls, free throws made and attempted. RESULTS: The players injured in the lumbar spine had better means, per minute played, in assists, probably by their continuous column twists to protect the ball with the body to avoid bumps. Players injured in the shoulder had more blocked shots per minute than those not injured, probably because the realization of a block involves a shoulder flexion and rotation. It would be interesting to carry out a specific follow-up in this type of player, for this type of injury. This information could be helpful to improve injury prevention with the use of KPIs of basketball

INTRODUCCIÓN: Las lesiones de la parte superior del cuerpo son menos frecuentes que las de las extremidades inferiores en baloncesto, pero aún existe la necesidad de conocer la relación entre su ocurrencia y los perfiles de rendimiento de jugadores profesionales. El objetivo de este estudio es analizar la relación entre la ocurrencia de lesiones de la parte superior del cuerpo y los factores de rendimiento clave (Key Performance Indicators, KPIs) en jugadores profesionales de baloncesto. MATERIAL Y MÉTODOS: Se ha analizado la información estadística de 554 jugadores (edad: 26,97 ± 4,86 años, estatura: 199,23 ± 8,80 cm, minutos por temporada: 441,18 ± 301,41) en la liga regular ACB durante dos temporadas (2012-13 y 2013-14). Además, se han recogido los partes médicos de cada jornada y categorizado las lesiones según el sistema OSICS 10. Los jugadores que jugaron más minutos durante la temporada fueron más propensos a sufrir lesiones en la columna lumbar, la cabeza, la muñeca y las manos. Los jugadores lesionados en la columna torácica obtuvieron un mejor promedio en robos por minuto. Los jugadores lesionados en la cabeza o el codo tuvieron un mejor rendimiento de +/- por minuto. RESULTADOS: Los jugadores lesionados en el cuello tuvieron mejores promedios por minuto en faltas recibidas, tiros libres realizados e intentados. Los jugadores lesionados en la columna lumbar tuvieron mejores promedios, por minuto jugado, en asistencias, probablemente por sus continuos giros de columna para proteger el balón con el cuerpo para evitar ayudas defensivas. Los jugadores lesionados en el hombro hicieron más tapones por minuto que aquellos no lesionados, probablemente porque la realización de un tapón implica una flexión y una rotación de hombro. Sería interesante realizar un seguimiento específico en este tipo de jugadores, para este tipo de lesiones. Esta información podría ser útil para mejorar la prevención de lesiones con el uso de KPIs en baloncesto

Lower extremity injuries and key performance indicators in professional basketball players / Lesiones de miembro inferior e indicadores clave de rendimiento en jugadores profesionales de baloncesto

In basketball, the most injured part of the body is the anatomical region that comprises the lower extremities. The aim of this study was to analyse the relationships among the occurrence of lower extremity injuries and Key Performance Indicators (KPIs) of professional basketball players. Statistical variables of 554 professional basketball players (age: 26.97±4.86 years, height: 199.23±8.80 cm, minutes per season: 441.18 ± 301.41) in ACB competition were analysed for two seasons (2012-13 and 2013-14). In addition, injury reports were registered and injuries were categorized taking into account OSICS-10 classification. The players who played the most minutes during the season were more likely to suffer ankle (P < 0.001) and knee (P < 0.05) injuries. The players injured in the ankle had better means, per minute played, in points, field goals made, free throws made and attempted, assists, fouls received and ranking (P < 0.05). The players injured in the knee obtained better average in most variables related to a positive performance: points, 2 points made and attempted, field goals made and attempted, free throws made and attempted, offensive rebounds, defensive rebounds, total rebounds, blocks made, dunks, received fouls, +/- statistic and ranking (P < 0.05). The players injured in the leg had better means per minute in 3 points made and attempted, and 2 points attempted (P < 0.05). Significant relationships were also found between injuries in the thigh and performance (better means in assists and steals, P < 0.05) and the foot injuries (defensive and total rebounds, dunks and fouls, P < 0.05). Higher performance in basketball involves a higher risk of injury in the lower extremities and this information could be useful to design injury prevention strategies

En el baloncesto, la región anatómica más lesionada es el miembro inferior. El objetivo de este estudio fue analizar la rela-ción entre la ocurrencia de lesiones en el miembro inferior y los factores de rendimiento clave (Key Performance Indicators, KPIs) en jugadores profesionales de baloncesto. Se ha analizado la información estadística de 554 jugadores de baloncesto profesional (edad: 26,97 ± 4,86 años, estatura: 199,23 ± 8,80 cm, minutos por temporada: 441,18 ± 301,41) en la liga regular ACB durante dos temporadas (2012-13 y 2013-14). Además, se han recogido los partes médicos de cada jornada y categorizado las lesiones según el sistema OSICS 10. Los jugadores que jugaron una mayor cantidad de minutos durante la temporada fueron más propensos a sufrir lesiones de tobillo (P < 0,001) y rodilla (P<0,05). Los jugadores lesionados en el tobillo tuvieron mejores promedios, por minuto jugado, en puntos, tiros de campo intentados, tiros libres anotados e intentados, asistencias, faltas recibidas y valoración (P < 0,05). Los jugadores lesionados en la rodilla obtuvieron un mejor promedio en la mayoría de las variables relacionadas con un rendimiento positivo: puntos, tiros de 2 anotados e intentados, tiros de campo anotados e intentados, tiros libres anotados e intentados, rebotes ofensivos, rebotes defensivos, rebotes totales, tapones realizados, mates, faltas recibidas, estadística +/- y valoración (P < 0,05). Los jugadores lesionados en la pierna tuvieron mejores promedios por minuto en triples convertidos e intentados, y tiros de 2 intentados (P < 0,05). También se encontraron relaciones significativas entre las lesiones en el muslo y el rendimiento (mejor promedio de asistencias y robos, P <0,05) y las lesiones del pie (rebotes defensivos y totales, mates y faltas, P < 0,05). Un mayor rendimiento en el baloncesto implica un mayor riesgo a lesionarse en el miembro inferior y esta información podría ser útil para diseñar estrategias de prevención de lesiones

The influence of ankle dorsiflexion on jumping capacity and the modified agility t-test performance.

Dorsiflexion sport shoes aim to increase jumping capacity and speed by means of a lower position of the heel in comparison with the forefoot, favouring additional stretching of the ankle plantar flexors. In previous studies, contradictory results have been found on the benefits of using this type of shoe. With the aim of comparing a dorsiflexion sport shoe model (DF) with a conventional sport shoe (CS), 41 participants performed a countermovement jump (CMJ) test and an agility test (MAT) with both models of shoe. There were no significant differences in the jump test [CS=35.3 cm (6.4) and DF=35.6 cm (6.4), P>0.05]. In the agility test, the conventional shoe obtained better results than the model with dorsiflexion with regard to time taken to complete the circuit [CS=6236 ms (540) and DF=6377 ms (507), P<0.05)]. In spite of producing pre-stretching of the plantar muscles, the DF sport shoes were not effective for improving either jump power or agility in a specific test.

Short-term training effects of vertically and horizontally oriented exercises on neuromuscular performance in professional soccer players.

PURPOSE: The aim of this study was to compare the effects of 2 strength and conditioning programs involving either purely vertically oriented or combining vertically and horizontally oriented exercises on soccer-relevant performance variables (ie, acceleration, jumping ability, peak power, and endurance). METHODS: Twenty-two professional male soccer players were randomly assigned to 2 training groups: vertical strength (VS, n = 11) and vertical and horizontal strength (VHS, n = 11). Players trained 2 times per week during all the preseason (5 wk) and 3 weeks of the competitive season. The effect of the training protocols was assessed using double-and single-leg vertical countermovement jumps (CMJ), half-squat peak power (PP), sprint performance over 5 and 15 m, and blood lactate concentration at selected running speeds. RESULTS: Both groups obtained significant improvements in PP (P < .05; ES = 0.87 and 0.80 for VS and VHS, respectively) and small practical improvements in 5-m- (P < .05; ES = 0.27 and 0.25 for VS and VHS, respectively) and 15-m-sprint time (P < .05; ES = 0.19 and 0.24 for VS and VHS, respectively). The CMJ performance showed a small improvement (P < .05, ES = 0.34) only in the VHS group. Submaximal aerobic-fitness changes were similar in both groups (P < .05; ES = 1.89 and 0 .71 for VS and VHS, respectively). CONCLUSION: This study provided a small amount of practical evidence for the consideration of preseason training protocols that combine exercises for vertical- and horizontal-axis strength development in professional male soccer players. Further studies using more aggressive training protocols involving horizontally oriented conditioning exercises are warranted.

Ocurrencia de lesiones y factores de rendimiento asociados en jugadores ACB / Injury occurrence and related performance factors in ACB players

El objetivo de este estudio es analizar la relación entre la ocurrencia de lesiones y los valores de rendimiento recogidos en las estadísticas oficiales de la liga ACB, variables antropométricas y de posición de juego. Se ha analizado la información estadística de 554 jugadores de baloncesto profesional (edad: 26,97±4,86 años, estatura: 199,23±8,80 cm, minutos por temporada: 441,18±301,41) en la liga regular ACB durante dos temporadas (2012-13 y 2013-14). Además, se han recogido los partes médicos de cada jornada y categorizado las lesiones según el sistema OSICS 10. También se han incluido variables de tipo antropométrico (peso, estatura e IMC) y la edad. Las lesiones con mayor incidencia fueron las de tobillo (77 jugadores; 23,7% del total de lesionados) y rodilla (52 jugadores; 16,0% del total de lesionados). No se encontraron relaciones entre el peso o el IMC y la ocurrencia de lesiones (P>0,05). Los escoltas, ala-pívots y pívots padecieron más lesiones de media que los bases y los aleros (P<0,05). Los jugadores que padecieron alguna lesión disputaron más minutos durante la temporada regular (527±260 vs. 380±315 min; P=0,000). Además, se observaron diferencias significativas (P<0,05) en las estadísticas por minuto de la liga ACB en puntos (0,382±0,114 vs. 0,352±0,284), valoración (0,391±0,172 vs. 0,290±0,469), rebotes (0,167±0,092 vs. 0,151±0,110), asistencias (0,066±0,045 vs. 0,062±0,065), tiros convertidos (0,138±0,047 vs. 0,125±0,083), tapones a favor (0,015±0,019 vs. 0,013±0,019), mates (0,013±0,022 vs. 0,009±0,017), recuperaciones (0,034±0,015 vs. 0,032±0,024), faltas recibidas (0,105±0,040 vs. 0,096±0,093), tiros libres intentados (0,093±0,044 vs. 0,091±0,166), estadística +/- (-0,013±0,241 vs. -0,124±0,640). Los jugadores que presentaron alguna lesión anatómica realizaron más acciones de media por minuto en todos los aspectos, excepto en los tapones en contra. Las variables de rendimiento estadístico de la liga ACB influyen en la ocurrencia de lesiones y las variables que indican acciones positivas implican un mayor riesgo de padecer lesiones

The aim of this study is to analyse whether there are significant relationships between the occurrence of injuries and official ACB statistical variables related to performance, anthropometry and play position. Statistical variables of 554 professional basketball players (age: 26.97±4.86 years, height: 199.23±8.80 cm, minutes per season: 441.18 ± 301.41) in ACB competition were analysed for two seasons (2012-13 and 2013-14). In addition, injury reports were registered and injuries were categorized taking into account OSICS-10 classification. Anthropometric variables (weight, height, BMI) and age were also analysed. Ankle (77 players; 23.7% of total injured players) and knee (52 players; 16.0% of total injured players) were the most reported injuries. There were no relationships between weight or BMI and the occurrence of injuries (P>0.05). Shooting-guards, power-forwards and centers suffered more injuries in average than point-guards and small-forwards (P<0.05). Players who reported any anatomical injury played more minutes during the regular season (527±260 vs. 380±315 min; P=0.000). Significant differences (P<0.05) were also found in statistics per minute of points (0.382±0,114 vs. 0.352±0,284), performance rating (0.391±0,172 vs. 0.290±0,469), rebounds (0.167±0,092 vs. 0.151±0,110), assists (0.066±0.045 vs. 0.062±0.065), goals made (0.138±0.047 vs. 0.125±0.083), blocks made (0.015±0.019 vs. 0.013±0.019), dunks (0.013±0.022 vs. 0.009±0,017), steals (0.034±0.015 vs. 0,032±0.024), received fouls (0.105±0.040 vs. 0.096±0.093), free throws attempted (0.093±0.044 vs. 0.091±0.166) and +/- statistic (-0.013±0.241 vs. -0.124±0.640). Players who were injured during the season did more actions per minute in average for every variable, excepting the blocks against. Statistical performance variables influence the occurrence of injuries, especially those variables that measure positive actions imply a higher risk of injury. Higher performance in basketball involves a higher risk of injury

La ingestión de una bebida energética con cafeína mejora la fuerza-resistencia y el rendimiento en escalada deportiva / The ingestion of a caffeine-containing energy drink improves resistance capacity and sport rock climbing performance

Introducción: Las bebidas energéticas con cafeína se han convertido en la ayuda ergogénica más empleada en el ámbito del deporte, por sus efectos demostrados para mejorar el rendimiento deportivo. El objetivo de este estudio fue analizar la influencia de las bebidas energéticas con cafeína en el rendimiento en escalada deportiva. Metodología: En dos días separados por una semana, 9 escaladores no profesionales ingirieron 3mg de cafeína por kg de peso corporal (en forma de una bebida energética en polvo comercial, Fure-Proenergetics®) o la misma bebida energética pero sin cafeína (prueba placebo, 0 mg/kg). El orden las pruebas experimentales fue asignado de forma aleatoria y contrabalanceado y el diseño experimental fue doble ciego. Sesenta minutos tras la ingestión de las bebidas experimentales, los participantes realizaron una dominada a la máxima velocidad posible y un test de dominadas hasta la fatiga, donde se midió la fuerza, velocidad y potencia. Posteriormente, se midió el tiempo de ascenso de una vía de escalada (dificultad V+), y dinamometría manual antes y después del ascenso. Resultados: Mientras que la ingestión de cafeína no afectó la potencia máxima en una dominada (696±423 kW con cafeína vs. 585±342 kW con placebo; P=0,376), el número de repeticiones (12,1±6,9 repeticiones con cafeína vs. 10,7±5,7 repeticiones con placebo, respectivamente; P=0,050) y la potencia total (5,51±4,42 kW con cafeína vs. 4,29±3,22 kW con placebo; P=0,04)durante el test de dominadas hasta la fatiga fueron incrementados por la ingestión de la bebida energética con cafeína en comparación a placebo. En comparación a placebo, la ingestión de bebida energética con cafeína mejoró la fuerza prensilsólo de la mano dominante (P<0,01). Además, el tiempo total de ascenso en la vía de escalada fue reducido significativamente con cafeína frente al placebo (257,6±108,2 vs 308,3±142,4 segundos, respectivamente; P=0,042). Conclusión: Las bebidas energéticas con cafeína pueden usarse como ayuda ergogénica para mejorar el rendimiento en la escalada deportiva, por su mejora en la fuerza-resistencia y en el tiempo empleado para completar una vía de dificultad media (AU)

Introduction: Caffeine energy drinks have become the most used ergogenic aid in the sport setting by its demonstrate deffects on physical performance. The aim of the study was to analyze the effect of a caffeine-containing energy drink on sport rock climbing. Methods: On two different days separated by a week, 9 non professional rock climbers were provided with 3 mg of caffeine per kg of body mass (by ingesting a commercially available energy drink, Fure-Proenergetics®), or the same drink but without caffeine (placebo trial, 0 mg/kg). The order of the experimental trials was randomized and counterbalanced and the experimental design was double blind. After sixty minutes for caffeine absorption, they performed a one-repetition maximal velocity pull-up test and a maximal number of repetitions pull-up test. Force, speed and power were measured in both tests. Then, they climbed a V+ difficult path as fast as they could while climbing time was recorded. Hand grip force was measured before and after the climbing test. Results: While caffeine ingestion did not improve maximal pull-up power (696±423 caffeine vs 585±342 kW placebo; P=0.376), the number of repetitions (12.1±6.9 vs 10.7±5.7 repetitions; P=0.050) and the total amount power during the pull-up test (5.51±4.42 kW vs 4.29±3.22 kW; P=0.04) was improved with energy drink ingestion in comparison to the placebo, respectively. In comparison to the placebo, energy drink ingestion improved hand grip force only in the dominant hand (P<0.01). In addition, climbing time was significantly reduced with the energy drink ingestion in comparison to placebo (257.6±108.2 vs308.3±142.4 seconds, respectively; P=0.042). Conclusion: Caffeine-containing energy drinks could be used as ergogenic aids in sport rock climbing due to its positive effects on muscle force-resistance and climbing performance (AU)

Efectos de una maratón en valores hematológicos / Marathon effects in hematic variables

La maratón lleva asociado un estrés fisiológico en el organismo, si bien existe carencia de información sobre cómo afecta a los parámetros sanguíneos en corredores populares y si existe relación con variables de rendimiento, entrenamiento y experiencia deportiva. Propósito: Evaluar los cambios producidos en variables hematológicas en corredores populares tras participar en una maratón en ambiente caluroso. Un segundo objetivo fue analizar la relación entre la experiencia deportiva, el nivel de entrenamiento y el tiempo de carrera con los cambios hematológicos. Métodos: Se extrajo sangre venosa a 41 maratonianos, 35 hombres y 6 mujeres, antes y después de una maratón. Su edad fue de 41,15+8,1 años, y entrenaban como media 55,9+17,12 kilómetros semanales. El tiempo en meta fue de 3:40:41+0:32:02.Las muestras fueron medidas con analizadores bioquímicos estándar para determinar los valores de la serie roja y serie blanca. Resultados: Se mostraron incrementos significativos (P<0,05) en los valores de la serie roja, pasando los hematíes de4,62+0,39 x10E3/uL a 4,71+0,42x10E3/uL, la hemoglobina de 14,33+1,02x10E6/uL a 14,58+1,13x10E6/uL, y el hematocrito de42,12+2,98% a 42,8+3,19%. En la serie blanca se incrementó el recuento leucocitario (P<0,001), siendo el valor pre 6,29+1,33x10E3/uL y el post 16,02+3,13x10E3/uL. La serie plaquetaria aumentó significativamente tanto el recuento de plaquetas (pre228,3+45,02x10E3/uL; post 272,9+45,83x10E3/uL, P<0,001) como el plaquetocrito (pre 2,03+0,3%; post 2,47+0,54%; P<0,001).El tiempo en meta presentó correlación significativa, aunque débil, con el cambio entre la toma inicial y final en el recuento de monocitos (r=-0,367; P=0,018), y en el volumen corpuscular medio (r=-0,485; P=0,001). Conclusión: La disputa de una carrera de maratón produce en corredores populares modificaciones hematológicas agudas en los parámetros habituales medidos con analizadores bioquímicos estándar. La experiencia deportiva, nivel de entrenamiento y tiempo en meta no parecen tener especial relación con estos parámetros (AU)

Introduction: Marathon supposes a physiological stress in the organism, but there is insufficiently information about how hematological values affecting runners. Also if there is relationship with performance, training and sporting experience variables. Purpose: The study was conducted to evaluate changes occurred in the main hematic variables in amateur runners, after their participation in a hot climate marathon. A second objective was to analyze the connection between sport experiences, training level and race time with the hematic changes. Methods: Blood samples were taken from 41 runners, 35 male and 6 female, before and immediately after the marathon. The mean training level was 55.9+17.12 km per week and the time race was 3:40:41+0:32:02 at a mean age of 41.15+8.1 years. Results: Samples were measured with biochemical standard analyzers and to determinate CBC and WBC counts. Significant differences (P<0.05) were found in CBC counts, increasing values of red blood cell from 4.62+0,39 x10E3/uL to 4,71+0,42x10E3/uL, haemoglobin from 14.33+1.02x10E6/uL to 14.58+1.13x10E6/uL and haematocrit from 42.12+2.98% to 42.8+3.19%. WBC counts showed also significant changes in leukocyte values (P<0.001) from 6.29 + 1.33 to 16.02 + 3.13 x10E3/uL, as well as in both, platelets values (P<0.001) from 228.3+45.02x10E3/uL to 272.9+45.83x10E3/uL and plateletcrit values (P<0.001) from2.03+0.3% to 2.47+0.54%. Race time was significantly correlated between initial and final monocite values, but poor (r=-0.367; P=0.018) and also between basal and final mean corpuscular volume (r=-0.485; P=0.001). Conclusion: Acute hematological changes occur in amateur runners after a marathon. No relationship was found between the hematic parameters and sport experience, training level and race time (AU)