Sleep quantity and quality ineliteyouth soccer players: A pilot study

The current study examined the effects of 10-h northbound air travel across 1 time zone on sleep quantity, together with subjective jet lag and wellness ratings, in 16 male professional Australian football (soccer) players. Player wellness was measured throughout the week before (home training week) and the week of (away travel week) travel from Australia to Japan for a preseason tour. Sleep quantity and subjective jet lag were measured 2 d before (Pre 1 and 2), the day of, and for 5 d after travel (Post 1–5). Sleep duration was significantly reduced during the night before travel (Pre 1; 4.9 [4.2−5.6] h) and night of competition (Post 2; 4.2 [3.7−4.7] h) compared with every other night (P < .01, d > 0.90). Moreover, compared with the day before travel, subjective jet lag was significantly greater for the 5 d after travel (P < .05, d > 0.90), and player wellness was significantly lower 1 d postmatch (Post 3) than at all other time points (P < .05, d > 0.90). Results from the current study suggest that sleep disruption, as a result of an early travel departure time (8 PM) and evening match (7:30 PM), and fatigue induced by competition had a greater effect on wellness ratings than long-haul air travel with a minimal time-zone change. Furthermore, subjective jet lag may have been misinterpreted as fatigue from sleep disruption and competition, especially by the less experienced players. Therefore, northbound air travel across 1 time zone from Australia to Asia appears to have negligible effects on player preparedness for subsequent training and competition.

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Post-training urinary titin fragment concentration increases in athletes with previous muscle strain injury: a pilot study in soccer players

The Journal of Physical Fitness and Sports Medicine ◽

10.7600/jpfsm.10.263 ◽

2021 ◽

Vol 10 (5) ◽

pp. 263-268

Author(s):

Tomonori Kawai ◽

Koichi Takamoto ◽

Itsumu Bito

Keyword(s):

Pilot Study ◽

Soccer Players ◽

Muscle Strain ◽

Muscle Strain Injury

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A genetic-based algorithm for recovery: A pilot study

10.1101/166181 ◽

2017 ◽

Author(s):

Craig Pickering ◽

John Kiely ◽

Bruce Suraci ◽

Charlie Quigley ◽

Jake Watson

Keyword(s):

Pilot Study ◽

Exercise Training ◽

Training Session ◽

The Body ◽

Soccer Players ◽

Sprint Training ◽

Need For Recovery ◽

Training Time ◽

Exercise Adaptation ◽

Physical Challenges

AbstractExercise training creates a number of physical challenges to the body, the overcoming of which drives exercise adaptation. The balance between sufficient stress and recovery is a crucial, but often under-explored, area within exercise training. Genetic variation can also predispose some individuals to a greater need for recovery after exercise. In this pilot study, 18 male soccer players underwent a repeated sprint training session. Countermovement jump (CMJ) heights were recorded immediately pre-and post-training, and at 24-and 48-hours post-training. The reduction in CMJ height was greatest at all post-training time points in subjects with a larger number of gene variants associated with a reduced exercise recovery. This suggests that knowledge of genetic information can be important in individualizing recovery timings and modalities in athletes following training.

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WAVE Virtual World Learning Environment for Childhood Obesity Prevention: High School Soccer Players’ Perspectives – A Pilot Study

The FASEB Journal ◽

10.1096/fasebj.30.1_supplement.896.4 ◽

2016 ◽

Vol 30 (S1) ◽

Author(s):

Siew Sun Wong ◽

Yu Meng ◽

Justin Bruntmyer ◽

Jianqing Cui ◽

Melinda M. Manore ◽

...

Keyword(s):

High School ◽

Childhood Obesity ◽

Pilot Study ◽

Learning Environment ◽

Obesity Prevention ◽

Virtual World ◽

Soccer Players ◽

Childhood Obesity Prevention

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Caffeine supplementation improves countermovement jump in youth soccer players: a pilot study

Revista Española de Nutrición Humana y Dietética ◽

10.14306/renhyd.21.2.331 ◽

2017 ◽

Vol 21 (2) ◽

pp. 155

Author(s):

Juan Diego Hernández-Camacho ◽

Javier Vázquez-Carrión ◽

Elena Fuentes-Lorca ◽

Heliodoro Moya-Amaya

Keyword(s):

Pilot Study ◽

Soccer Players ◽

Placebo Control ◽

Countermovement Jump ◽

Youth Soccer ◽

Los Grupos

Introducción: El objetivo del presente estudio fue analizar el efecto de la ingestión de cafeína en el rendimiento en fútbol, específicamente en el test de salto en contramovimiento (CMJ).Materiales y métodos: 17 jugadores de la categoría Sub-19 de un equipo amateur español participaron en el estudio piloto. Se siguió un diseño a doble ciego, placebo-control, aleatorizado en 2 entrenamientos (1,5 horas/sesión) separados por 1 semana. El CMJ se recogió al inicio y al final de las sesiones, la tasa de esfuerzo percibido (RPE) fue recogida. Los jugadores tomaron cafeína o placebo al inicio del entrenamiento (minuto 0), proveyendo 4 mg/kg de masa corporal de cafeína o placebo. Se analizaron los efectos secundarios provenientes de la cafeína y del placebo. Los tamaños de efecto (ES) se calcularon utilizando valores para Cohen y las diferencias cuantitativas se evaluaron cualitativamente (QA).Resultados: La altura del salto media cuando se ingirió cafeína fue 37,03 (±3,87) cm al inicio y 39,35 (±4,05) cm al final del entrenamiento, obteniendo una mejora significativa (p<0,05; ES: 0,56; QA: 99/1/0). Se observaron diferencias significativas en el CMJ al final de los entrenamientos entre la ingestión con cafeína y placebo (39,35 [±4,05] cm vs. 36,85 [±3,15] cm; p<0,05; ES: 0,65; QA: +0/1/99). Se obtuvieron diferencias significativas en la RPE entre los grupos. Se observó una tendencia no significativa a sufrir más efectos secundarios cuando se ingirió cafeína.Conclusiones: Este estudio muestra como la ingestión de 4 mg/kg de cafeína podría ser una ayuda ergogénica para mejorar el rendimiento en fútbol. Se requieren más estudios con mayor tamaño muestral para confirmar los resultados.

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