Physical and metabolic demands of training and match-play in the elite football player

In soccer, the players perform intermittent work. Despite the players performing low-intensity activities for more than 70% of the game, heart rate and body temperature measurements suggest that the average oxygen uptake for elite soccer players is around 70% of maximum (VO(2max). This may be partly explained by the 150 - 250 brief intense actions a top-class player performs during a game, which also indicates that the rates of creatine phosphate (CP) utilization and glycolysis are frequently high during a game. Muscle glycogen is probably the most important substrate for energy production, and fatigue towards the end of a game may be related to depletion of glycogen in some muscle fibres. Blood free-fatty acids (FFAs) increase progressively during a game, partly compensating for the progressive lowering of muscle glycogen. Fatigue also occurs temporarily during matches, but it is still unclear what causes the reduced ability to perform maximally. There are major individual differences in the physical demands of players during a game related to physical capacity and tactical role in the team. These differences should be taken into account when planning the training and nutritional strategies of top-class players, who require a significant energy intake during a week.     

Fluid and electrolyte needs for training, competition, and recovery

Fluids and electrolytes (sodium) are consumed by athletes, or recommended to athletes, for a number of reasons, before, during, and after exercise. These reasons are generally to sustain total body water, as deficits (hypohydration) will increase cardiovascular and thermal strain and degrade aerobic performance. Vigorous exercise and warm/hot weather induce sweat production, which contains both water and electrolytes. Daily water (4-10 L) and sodium (3500-7000 mg) losses in active athletes during hot weather exposure can induce water and electrolyte deficits. Both water and sodium need to be replaced to re-establish "normal" total body water (euhydration). This replacement can be by normal eating and drinking practices if there is no urgency for recovery. But if rapid recovery (<24 h) is desired or severe hypohydration (>5% body mass) is encountered, aggressive drinking of fluids and consuming electrolytes should be encouraged to facilitate recovery for subsequent competition.     

Fluid and electrolyte needs for preparation and recovery from training and competition

For a person undertaking regular exercise, any fluid deficit that is incurred during one exercise session can potentially compromise the next exercise session if adequate fluid replacement does not occur. Fluid replacement after exercise can, therefore, frequently be thought of as hydration before the next exercise bout. The importance of ensuring euhydration before exercise and the potential benefits of temporary hyperhydration with sodium salts or glycerol solutions are also important issues. Post-exercise restoration of fluid balance after sweat-induced dehydration avoids the detrimental effects of a body water deficit on physiological function and subsequent exercise performance. For effective restoration of fluid balance, the consumption of a volume of fluid in excess of the sweat loss and replacement of electrolyte, particularly sodium, losses are essential. Intravenous fluid replacement after exercise has been investigated to a lesser extent and its role for fluid replacement in the dehydrated but otherwise well athlete remains equivocal.     

Fluid and electrolyte needs for preparation and recovery from training and competition

For a person undertaking regular exercise, any fluid deficit that is incurred during one exercise session can potentially compromise the next exercise session if adequate fluid replacement does not occur. Fluid replacement after exercise can, therefore, frequently be thought of as hydration before the next exercise bout. The importance of ensuring euhydration before exercise and the potential benefits of temporary hyperhydration with sodium salts or glycerol solutions are also important issues. Post-exercise restoration of fluid balance after sweat-induced dehydration avoids the detrimental effects of a body water deficit on physiological function and subsequent exercise performance. For effective restoration of fluid balance, the consumption of a volume of fluid in excess of the sweat loss and replacement of electrolyte, particularly sodium, losses are essential. Intravenous fluid replacement after exercise has been investigated to a lesser extent and its role for fluid replacement in the dehydrated but otherwise well athlete remains equivocal.     

Defining the attributes for specific playing positions in football match-play: A complex systems approach

ABSTRACT

Introduction

Talent identification and development programmes that retain and develop athletes are integral to the sporting success of National Governing Bodies in football. Currently, player attributes are studied in isolation without considering the complexity of interacting components of football performance. The current study applied a systems analysis framework to describe, in a structured and systematic way, the attributes for specific playing positions in football match-play. Methods: Eight high-level football coaches were interviewed. Models of the interacting attributes were developed for each position using Work Domain Analysis (WDA). Results: Six WDA models detail the attributes associated with each playing position. The models identified purposes of playing positions (restrict opposition actions, organise and coordinate, building up of offence, goal scoring and stretch opposition), performance-related measures and the functions required to achieve the playing position purposes (game play, psychological functions, time and space and player actions). Critically, the relationships between the purposes, measures, functions, processes, and objects are described in the models.     

Circadian variation and soccer performance: implications for training and match-play during Ramadan

Ramadan results in a number of behavioural alterations in individuals when compared to their normal habits outside of this holy month. These changes in behaviour could impact upon the effectiveness of the activity of an elite athlete who has high daily activity levels and energy expenditures. Understanding the true impact of Ramadan on human physiology will also require an awareness of the key aspects of circadian rhythms. This article will present theoretical background content on circadian rhythms along with data on the potential influence of circadian variation on soccer performance. It will also attempt to provide an insight into the problems of partial sleep deprivation and travel for the elite player. The contents will suggest that there is a basis for the within-day variation in physiological and psychological function to impact soccer performance if games are played early in the day or very late at night. As competitive fixtures are uncommon at these times these influences may be more relevant to the timing and organisation of training sessions. It is also likely that a lack of sleep and excessive travel will provide conditions that are not conducive to optimal performance. This would indicate that teams should think carefully about their preparation strategies for important tournaments and games.     

Fluid and electrolyte balance in elite male football (soccer) players training in a cool environment

There are few data in the published literature on sweat loss and drinking behaviour in athletes training in a cool environment. Sweat loss and fluid intake were measured in 17 first-team members of an elite soccer team training for 90 min in a cool (5 degrees C, 81% relative humidity) environment. Sweat loss was assessed from the change in body mass after correction for the volume of fluid consumed. Sweat electrolyte content was measured from absorbent patches applied at four skin sites. Mean (+/- s) sweat loss during training was 1.69+/-0.45 l (range 1.06-2.65 l). Mean fluid intake during training was 423+/-215 ml (44-951 ml). There was no apparent relationship between the amount of sweat lost and the volume of fluid consumed during training (r2 = 0.013, P = 0.665). Mean sweat sodium concentration was 42.5+/-13.0 mmol l(-1) and mean sweat potassium concentration was 4.2+/-1.0 mmol x l(-1). Total salt (NaCl) loss during training was 4.3+/-1.8 g. The sweat loss data are similar to those recorded in elite players undergoing a similar training session in warm environments, but the volume of fluid ingested is less.     

Fluid and electrolyte balance in elite male football (soccer) players training in a cool environment

There are few data in the published literature on sweat loss and drinking behaviour in athletes training in a cool environment. Sweat loss and fluid intake were measured in 17 first-team members of an elite soccer team training for 90 min in a cool (5°C, 81% relative humidity) environment. Sweat loss was assessed from the change in body mass after correction for the volume of fluid consumed. Sweat electrolyte content was measured from absorbent patches applied at four skin sites. Mean (?± s) sweat loss during training was 1.69?±?0.45 l (range 1.06?-?2.65 l). Mean fluid intake during training was 423?±?215 ml (44?-?951 ml). There was no apparent relationship between the amount of sweat lost and the volume of fluid consumed during training (r ² = 0.013, P = 0.665). Mean sweat sodium concentration was 42.5?±?13.0 mmol?·?l^?1 and mean sweat potassium concentration was 4.2?±?1.0 mmol?·?l^?1. Total salt (NaCl) loss during training was 4.3?±?1.8 g. The sweat loss data are similar to those recorded in elite players undergoing a similar training session in warm environments, but the volume of fluid ingested is less.     

沙滩足球训练与传统足球训练对足球运动员有氧及无氧运动能力影响的比较研究

选取反映足球运动员有氧及无氧运动能力的代表性指标乳酸阈、最大无氧功率,设计分组教学实验:将24名实验对象分为实验组和对照组,分别进行长达17周(5次/周)的沙滩足球训练和传统足球训练.对分组教学实验前后的各项数据进行对比分析得出结论:1)实验组与对照组的无氧功率指标产生显著性差异,实验组的指标显著提高,可知沙滩足球训练可以有效提高足球运动员的无氧运动能力.2)实验组与对照组的乳酸阈指标产生显著性差异;另外,通过分析跑动过程中各个时间段运动员心率的变化情况发现,分组教学实验后9 min～12 min心率开始产生变化,由此可知沙滩足球训练可以有效提高足球运动员的有氧运动能力.     

Incorporating perceptual decision-making training into high-intensity interval training for Australian football umpires

Existing methods for developing decision–making skill for Australian football umpires separate the physical and perceptual aspects of their performance. This study aimed to determine the efficacy of incorporating video-based decision-making training during high-intensity interval training sessions, specific for Australian football umpires. 20 amateur Australian football umpires volunteered to participate in a randomised control trial. Participants completed an 8-week training intervention in a conditioning only (CON; n=7), combined video-based training and conditioning (COM; n=7), or separated conditioning and video-based training (SEP; n=6) group. Preliminary and post-testing involved a Yo-Yo Intermittent Recovery Test (Yo-YoIR1), and 10x300m run test with an Australian football specific video-based decision-making task. Overall, changes in decision-making accuracy following the intervention were unclear between groups. SEP was possibly beneficial compared to COM in Yo-YoIR1 performance, whereas CON was likely beneficial compared to COM in 10x300m sprint performance. There was no additional benefit to completing video-based training, whether combined with, or separate to physical training, suggesting that this was not an optimal training method. For video-based training to be an effective decision-making tool, detailed feedback should be incorporated into training. It is recommended that longer conditioning and video-based training interventions be implemented to determine training effectiveness.     

The appropriateness of training exposures for match-play preparation in adolescent schoolboy and academy rugby union players

The aim of this study was to compare the physical and movement demands between training and match-play in schoolboy and academy adolescent rugby union (RU) players. Sixty-one adolescent male RU players (mean ± SD; age 17.0 ± 0.7 years) were recruited from four teams representing school and regional academy standards. Players were categorised into four groups based on playing standard and position: schoolboy forwards (n = 15), schoolboy backs (n = 15), academy forwards (n = 16) and academy backs (n = 15). Global positioning system and accelerometry measures were obtained from training and match-play to assess within-group differences between conditions. Maximum data were analysed from 79 match files across 8 matches (1.3 ± 0.5 matches per participant) and 152 training files across 15 training sessions (2.5 ± 0.5 training sessions per participant). Schoolboy forwards were underprepared for low-intensity activities experienced during match-play, with schoolboy backs underprepared for all movement demands. Academy forwards were exposed to similar physical demands in training to matches, with academy backs similar to or exceeding values for all measured variables. Schoolboy players were underprepared for many key, position-specific aspects of match-play, which could place them at greater risk of injury and hinder performance, unlike academy players who were better prepared.     

Pre-cooling for football training and competition in hot and humid conditions

Abstract

Pre-cooling studies report positive physiological and performance benefits in laboratory conditions, although research studies have not investigated these reported benefits in ecologically valid team-sport training and competition settings. Accordingly, this study investigated the effect of field-based pre-cooling strategies for professional football players during training and competition in the heat. Ten professional football players from an Australian A-League club performed two training sessions and competitive matches in hot ambient conditions (29±3^oC, 78±8% relative humidity) with or without pre-cooling. The pre-cooling intervention involved 20-min of an ice-vest, cold towels and 350 mL ice-slushie drink. Training sessions (n=9) were randomised, and consisted of 2 x 10-min interval training, followed by 6 x 3-min of 5v5 small sided games. Competitions (n=7) involved official A-League matches during the 2009–10 season. Player movement characteristics, core temperature (gastrointestinal), skin temperature, nude mass, heart rate, capillary blood (glucose, K⁺, Na⁺, haematocrit), perceptual exertion and thermal stress measures were recorded. No significant differences (P>0.05) were present between conditions for any measure of physical performance, although moderate-large effects for a greater total and relative distance covered during training were present (d > 0.8). While mean skin temperature was reduced following cooling, core temperature was only lower until following the warm-up in training and was even less evident during matches (P>0.05; d < 0.6). However, a smaller change in mass (sweat loss) and reduced perceptual exertion and thermal stress were evident during training following cooling (d > 0.9), although again, to a much lesser extent in matches (d = 0.6). In conclusion, equivocal findings were present for the effects of pre-cooling for professional football players during competitive training and matches in the heat. However, performance and thermoregulatory response trends showed similarities to previous laboratory evidence. The field-based nature of the current study may highlight that the transfer of lab findings to field settings is difficult or the strength of the intervention is diminished by the settings.     

关于足球运动员专项适应性训练的分析探讨

现代足球运动朝着“高速度,强对抗”的方向飞速发展,要求运动员必须有“超强”的体能。本文结合足球比赛技、战术运用的特点和足球运动体能的主要特征,指出发展运动员的体能必须以该项目的专项需求作为依据,把无氧训练和有氧训练结合起来进行,从而使足球运动员的专项适应性训练达到最佳化。     

现阶段我国足球运动员体能训练结构的分析与训练对策

从当今职业化足球比赛对运动员的体能要求出发,分析我国职业球员体能现状,通过对足球运动员体能水平构成因素的分析及比赛中体能表现的研究,探讨符合足球运动规律的体能训练方法,为足球体能训练监控提供依据。     

Fluid needs for training and competition in athletics

The diverse nature of the athletic events, together with the varied training programmes and individuality of athletes taking part, inevitably means that fluid needs are highly variable--between athletes, perhaps between training and competition, and with differing environmental conditions and degree of training and heat acclimatization. There are limited data from athletics on all aspects of fluid balance, but wherever possible we have focused on this information to draw conclusions. When appropriate, euhydration will best be ensured by consuming 6-8 ml . kg body mass(-1) of a sodium-containing fluid, or sodium-free fluid together with food, about 2 h before exercise. The individual sweat responses are so variable that athletes should assess their own individual sweat losses to determine if these are likely to be a cause for concern. The volume of drink that is consumed should never be so much that an athlete gains mass over an event, unless perhaps there is evidence that they began in a hypohydrated state. This may be a particular concern in the field events and multi-event disciplines when competition can be spread over a number of hours and when there are significant rest periods between activities.     

足球运动员耐力素质训练的新思考

足球运动员主要需要快速能源系统供能,需要在比赛各部分之间快速恢复的能力,以及反复产生最大力量的能力,因此,足球运动员的体能训练应重点放在爆发式的快速冲刺(20m左右)、冲顶、堵截等方面,无氧耐力素质训练应与足球技战术训练联系起来进行.     

基于Internet的足球战术教学与训练信息交互平台的开发研究

以现有的Internet网络硬件为运行基础,利用网络多媒体开发工具,结合相关学科的理论与方法,根据足球基本战术教学与训练大纲的要求,设计开发可进行网络远程服务的足球战术教学与训练信息交互平台。     

足球运动员射门技术的心理分析及训练方法

现代足球比赛的对抗越来越激烈,射门技术对比赛的胜负已起到关键的作用,心理因素对足球射门技术的影响很大,特别是在关键性的比赛中,通过对影响足球射门成功时心理状态的分析,加强对足球射门训练方法中心理训练的研究,并提出一些相关的意见和建议。     

浅谈青少年足球训练中存在的问题与对策

以青少年足球训练为切入点,在分析青少年足球训练中存在的问题的基础上,探讨解决青少年足球训练中问题的对策,旨在说明青少年足球训练的重要性,以期为青少年足球训练提供参考。     

我国足球训练基地发展布局现状及对策

我国足球训练基地发展、布局有其自身特点,在特定时期发挥了重要作用。但从足球训练基地的布局上看,基地建设还存在一些问题。尽管几个大的训练基地布局比较合理,但是仍然存在目标不一致,项目不配套,无序竞争等问题。