Influence of Shoe Mass on Performance and Running Economy in Trained Runners

Purpose The aim of this study was to assess the effects of adding shoe mass on running economy (RE), gait characteristics, neuromuscular variables and performance in a group of trained runners. Methods Eleven trained runners (6 men and 5 women) completed four evaluation sessions separated by at least 7 days. The first session consisted of a maximal incremental test where the second ventilatory threshold (VT2) and the speed associated to the VO2max(vVO(2max)) were calculated. In the next sessions, RE at 75, 85, and 95% of the VT(2)and the time to exhaustion (TTE) at vVO(2max)were assessed in three different shoe mass conditions (control, +50 g and +100 g) in a randomized, counterbalanced crossover design. Biomechanical and neuromuscular variables, blood lactate and energy expenditure were measured during the TTE test. Results RE worsened with the increment of shoe mass (Control vs. 100 g) at 85% (7.40%, 4.409 +/- 0.29 and 4.735 +/- 0.27 kJ.kg(-1).km(-1),p= 0.021) and 95% (10.21%, 4.298 +/- 0.24 and 4.737 +/- 0.45 kJ.kg(-1).km(-1),p= 0.005) of VT2. HR significantly increased with the addition of mass (50 g) at 75% of VT2(p= 0.01) and at 75, 85, and 95% of VT2(p= 0.035, 0.03, and 0.03, respectively) with the addition of 100 g. TTE was significantly longer (similar to 22%, similar to 42 s,p= 0.002,ES= 0.149) in the Control condition vs. 100 g condition, but not between Control vs. 50 g (similar to 24 s,p= 0.094,ES= 0.068). Conclusion Overall, our findings suggest that adding 100 g per shoe impairs running economy and performance in trained runners without changes in gait characteristics or neuromuscular variables. These findings further support the use of light footwear to optimize running performance

Swimming World Championships:Association between success at junior and senior level for British swimmers

The present study examines the association between the success at junior and senior level for British swimmers in World Championships (WCs). It also explores the relationships between swimming performance and the swimmers’ gender, swim stroke, distance, status (finalist, semifinalist and heats) and swimming category. Data were collected for swimmers participating in junior and/or senior World Championships (29,000 entries: 5585 swimmers) from 2006–2017. The final filtered database included only swimmers from the United Kingdom (836 entries: 141 swimmers). A descriptive analysis was made to characterize the swimmers who reached elite status in the senior category. A lineal regression model was run by gender to predict the influence of category, swim stroke, and distance in the results reached in the senior category. The results showed that the ratio of conversion from junior to senior was quite low. Females who participated in both junior and senior WCs were likely to reach top positions in the senior category. Overall, few British swimmers participated in a junior category before the senior level, but female swimmers participating in both junior and senior WCs were likely to reach top positions in the senior category.post-print335 K

Anti-Doping Knowledge of Students Undertaking Bachelor’s Degrees in Sports Sciences in Spain

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 dopin

Commentaries on viewpoint : physiology and fast marathons

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Esfuerzos de alta y baja intensidad y sus efectos agudos y a medio plazo en la economía de carrera de corredores de diferentes niveles de rendimiento

El entrenamiento de alta intensidad ha incrementado su importancia y estudio durante los últimos años. Sin embargo, el entrenamiento de alta intensidad se ha caracterizado principalmente por el uso del método de entrenamiento interválico, el cual lleva utilizándose durante varias décadas, pero, sus efectos en el organismo de los corredores y en el rendimiento necesita aún más conocimiento y estudios al respecto. Por ello, el objetivo de la presente Tesis es evaluar los efectos de esfuerzos de alta intensidad (efectuados durante un período de entrenamiento o durante el calentamiento previo a la prueba de rendimiento) principalmente en la economía de carrera, así como en otras variables como neuromusculares, biomecánicas y en el rendimiento de atletas de resistencia de diferentes niveles. Para ello, se ha realizado una revisión bibliográfica (Artículo I) para exponer los antecedentes de la temática y vislumbrar las vías nuevas de estudio, y de tal revisión, parten dos estudios experimentales (Artículo II y III), en la que se evalúan los efectos de la realización de esfuerzos de alta intensidad a medio plazo (Artículo II) en comparación con esfuerzos de baja intensidad, y además, los efectos agudos de la realización de esfuerzos de alta intensidad durante el calentamiento previo a una prueba de rendimiento en la economía de carrera (coste de oxígeno o coste de energía) como variable principal. Los principales resultados de la presente Tesis sugieren que: a) El entrenamiento continuo (baja intensidad) mejora la economía de carrera en corredores de nivel recreacional. b) El entrenamiento interválico (alta intensidad) mejora la velocidad aeróbica máxima, modificando a su vez la cinemática de carrera, incrementándose la longitud de paso y reduciéndose el tiempo de contacto con el suelo. c) La inclusión de esfuerzos de alta intensidad durante el calentamiento previo a un test de rendimiento, mejora el rendimiento posterior en comparación a un esfuerzo de baja intensidad. d) Todas las condiciones de calentamiento incrementaron el coste de energía posterior al mismo, debido principalmente a una reducción en el cociente respiratorio y consecuente cambio en el sustrato energético, reducción en la frecuencia de paso y, a su vez, las condiciones de alta intensidad (llano y cuesta) incrementaron el lactato sanguíneo tras tales esfuerzos en el calentamiento. e) Tras el test de rendimiento, el lactato sanguíneo se incrementó significativamente en todas las condiciones

Training periodization for a world-class 400 meters individual medley swimmer

We present a case study of the periodized training by a world-class 400-m Individual Medley (IM) swimmer (4th in 2019 World Championships) in the season leading to a bronze medal in the 2018 European Championship. The complexity of this IM preparation was based on the experiences, observations and innovations of an Olympic swimming coach. Over 52 weeks, a traditional periodization model was employed using three macrocycles. A total of 15 competitions were completed in the season increasing in frequency in the third macrocycle. The training intensity distribution (TID) followed the pattern of a traditional pyramidal model in general training and polarized and threshold models during specifictraining before competitions. Weekly training volume ranged from 25 to 79 km, 24 to 87 km, and 25 to 90 km in each of the three macrocyles. Altitude training comprised 23% of total training weeks. Haemoglobin [Hb] increased from 14.9 to 16.0 g/100 ml and haematocrit from 45.1 to 48.1% after altitude training. Heart rate (HR) and [La- ] decreased at submaximal swimming intensities, while swimming velocity increased in the 8×100 m incremental swimming test in A2(1.4%) and in AT (0.6%). Pull up power was increased 10% through the season

Acute effects of combined cycling and plyometrics on vertical jump performance in active males

The aim of this study was to analyze the acute effects of high vs low-intensity cycling efforts, combined with plyometrics, on vertical jump performance. Twenty-four physically active men (mean ±SD: 23 ± 2 years, 72.1 ± 10.1 kg, 1.73 ± 0.07 m) were randomly divided into two groups: experimental group (EXP, n = 16) and control group (CON, n = 8). EXP competed 2 experimental trials in a random order: (a) short high-intensity interval exercise (HI + Plyo) [5 × 10 s of cycling (“all-out”)/50 s active rest] or (b) low-intensity continuous exercise (LO + Plyo) [5 min of cycling at 75% of the HRmax)], along with 3 × 10 plyometric bounds (drop jumps)/1 min rest between sets. CON used a preconditioning activity of 13 min of low intensity cycling at ~60% of HRmax. Both EXP interventions significantly increased (p ≤ 0.05) the countermovement jump (CMJ) height at 1 min, 3 min, 6 min and 9 min compared to baseline, while the CON remained unchanged. There were no significant differences in CMJ performance enhancement between HI + Plyo (largest 11.2% at 9 min) and LO + Plyo (largest 15.0% at 3 min) at any time-point, suggesting that the plyometric component may be most important, with HR recovery taking slightly longer following HI + Plyo. The findings suggest that CMJ performance can be enhanced following high or low-intensity cycling combined with plyometric preconditioning activities in active males, the optimum recovery period likely to be individual-specific

Influence of early specialization in world-ranked swimmers and general patterns to success.

ObjectivesThe primary goal was to examine the influence of early specialization on the performance of senior elite swimmers. Secondly, to provide information about the influence of swim style, distance, sex, status, country, years of high-level competition (YHLC) and age in swimmer's performance.DesignData was obtained from International Federation of Swimming (FINA) regarding the participants 2006-2017 of junior and senior World Championships (WCs). The final filtered database included 4076 swimmers after removing those participating only in junior WCs.MethodCramer V coefficient, double and triple-entry tables were used to measure the relationship between the positions occupied in junior and senior phases. A One-Way ANOVA analysis was used to explain the variables time and rank between swimmers who participated in junior and senior WC or just in senior in all the distances and swim styles (SS). A univariate general linear model (GLM) was used to examine the association between time/rank and category (swimmers that participated previously in junior WC or not); YHLC; country; status (highest finishing position: final/semi-final/heats) and age.ResultsSignificant differences (p ConclusionCompeting in junior WC has a positive influence in achieve posteriori success in FINA WC. YHLC have a positive impact to achieve better positions