The Loughborough Intermittent Shuttle Test: A field test that simulates the activity pattern of soccer

The aims of this study were to describe and determine the test-retest reliability of an exercise protocol, the Loughborough Intermittent Shuttle Test (the LIST), which was designed to simulate the activity pattern characteristic of the game of soccer. The protocol consisted of two parts: Part A comprised a fixed period of variable-intensity shuttle running over 20 m; Part B consisted of continuous running, alternating every 20 m between 55% and 95% VO 2max , until volitional fatigue. Seven trained games players (age 21.5 +/- 0.9 years, height 182 +/- 2 cm, body mass 80.1 +/- 3.6 kg, VO 2max 59.0 +/- 1.9 ml kg -1 min -1 ; mean s x ) performed the test on two occasions (Trial 1 and Trial 2), at least7 days apart, to determine the test-retest reliability of the sprint times and running capacity. The physiological and metabolic responses on both occasions were also monitored. The participants ingested water ad libitum during the first trial, and were then prescribed the same amount of water during the second trial. The 15 m sprint times during Trials 1 and 2 averaged 2.42 +/- 0.04 s and 2.43 +/- 0.04 s, respectively. Run time during Part B was 6.3 +/- 2.0 min for Trial 1 and 6.1 +/- 1.3 min for Trial 2. The 95% limits of agreement for sprint times and run times during Part B were -0.14 to 0.12 s and -3.19 to 2.16 min respectively. There were no differences between trials for heart rate, rating of perceived exertion, body mass change during exercise, or blood lactate and glucose concentrations during the test. Thus, we conclude that the sprint times and the Part B run times were reproducible within the limits previously stated. In addition, the activity pattern and the physiological and metabolic responses closely simulated the match demands of soccer.     

Pulmonary Function at Rest and during Exercise in Uncomplicated Obesity

Abstract

Nine lean (6.9%–19.3% body fat) and 12 moderately obese (31.6%–42.3% body fat) college men were compared in terms of maximum aerobic power, resting pulmonary function tests, and selected respiratory variables during a progressive bicycle ergometer test. The [Vdot]O₂ max (1/min) was slightly higher (p > .05) in the obese group but significantly lower (p < .05) when expressed in cc/kg min or cc/kg FFBW min. Lower RV, ERV, and FRC data were observed in the obese group, but no differences were documented for tests of FVC or MVV. Higher values were displayed by the obese subjects for [Vdot]E, [Vdot]A, and tidal volume at rest and during each submaximal intensity of bicycle work. These observations appeared to be due to the obese subjects' higher energy expenditures, since no differences were documented in the ventilation equivalent ([Vdot]E/[Vdot]O₂), the [Vdot]A/[Vdot]E ratio, or breathing frequency. It was concluded, within the limitations of the study, that the hypothesis of respiratory dysfunction in the moderately obese was not supported.     

Book reviews

Richard Cox, Sport — A Guide to Historical Sources in the UK (London, Sports Council, 1983). Pp.vii + 61. £8.00 ISBN 0 906577 34 9.

P.B. Munsche, Gentlemen and Poachers: The English Game Laws 1671–1831 (Cambridge, CUP, 1983). Pp.x + 255. £18.50. ISBN 0 521 23284 8.

Garry Whannel, Blowing the Whistle: The Politics of Sport (London, Pluto Press, 1983). Pp. 117. £2.50. ISBN 0 86104 508 4.

David Smith and Gareth Williams, Fields of Praise: The Official History of the Welsh Rugby Union 1881–1981 (Cardiff, University of Wales Press, 1980). Pp.xii + 505. £12.95. ISBN 0 7083 07663.

John Arlott, Jack Hobbs — Profile of ‘The Master’ (London, John Murray and Davis‐Poynter, 1981). Pp. 144. £6.95. ISBN 07195 3886 6 (John Murray) and 0 7067 0214 X (Davis‐Poynter).

Richard S. Gruneau, Class, Sports and Social Development (Amherst, The University of Massachusetts Press, 1983). Pp.x + 213. $18.50 and $9.50. ISBN 0 87023 387 4 and 0 87023 388 2.

R. Roberts, Jack Dempsey: The Manassa Mauler (London, Louisiana State University Press 1984). Pp.314. £8.50. ISBN 8071 1161 9.

Richard Cashman and Michael McKernan (eds.), Sport: Money, Morality and the Media (Kensington, NSW, New South Wales University Press, 1981). Pp. 343. ISBN 0 86840 160 9.     

Modelling mood states in athletic performance

The ability to recognize patterns of play is fundamental to performance in team sports. While typically assumed to be domain-specific, pattern recognition skills may transfer from one sport to another if similarities exist in the perceptual features and their relations and/or the strategies used to encode and retrieve relevant information. A transfer paradigm was employed to compare skilled and less skilled soccer, field hockey and volleyball players' pattern recognition skills. Participants viewed structured and unstructured action sequences from each sport, half of which were randomly represented with clips not previously seen. The task was to identify previously viewed action sequences quickly and accurately. Transfer of pattern recognition skill was dependent on the participant's skill, sport practised, nature of the task and degree of structure. The skilled soccer and hockey players were quicker than the skilled volleyball players at recognizing structured soccer and hockey action sequences. Performance differences were not observed on the structured volleyball trials between the skilled soccer, field hockey and volleyball players. The skilled field hockey and soccer players were able to transfer perceptual information or strategies between their respective sports. The less skilled participants' results were less clear. Implications for domain-specific expertise, transfer and diversity across domains are discussed.     

Landing ground reaction forces in figure skaters and non-skaters

Abstract

Researchers and clinicians have suggested that overuse injuries to the lower back and lower extremities of figure skaters may be associated with the repeated high impact forces sustained during jump landings. Our primary aim was to compare the vertical ground reaction forces (GRFs) in freestyle figure skaters (n = 26) and non-skaters (n = 18) for the same barefoot single leg landing on a force plate from a 20 cm platform. Compared with non-skaters, skaters exhibited a significantly greater normalised peak GRF (3.50 ± 0.47 × body weight for skaters vs. 3.13 ± 0.45 × body weight for non-skaters), significantly shorter time to peak GRF (81.21 ± 14.01 ms for skaters vs. 93.81 ± 16.49 ms for non-skaters), and significantly longer time to stabilisation (TTS) of the GRF (2.38 ± 0.07 s for skaters vs. 2.22 ± 0.07 s for non-skaters). Skaters also confined their centre of pressure (CoP) to a significantly smaller mediolateral (M–L) (25%) and anterior–posterior (A–P) (40%) range during the landing phase, with the position of the CoP located in the mid to forefoot region. The narrower and more forward position of the CoP in skaters may at least partially explain the greater peak GRF, shorter time to peak, and longer TTS. Training and/or equipment modification serve as potential targets to decrease peak GRF by distributing it over a longer time period. More comprehensive studies including electromyography and motion capture are needed to fully characterise the unique figure skater landing strategy.     

An objective method for depicting team performance in elite professional rugby union

Abstract

Using a two-study approach, we examined a methodology for objectively depicting team performance and form in a professional rugby union side. Study 1 developed standardized indicators to examine a team's performance in a single match relative to their previous matches over a domestic season via a performance report and form chart. This resulted in standardized performance indicators that provided instant and coherent feedback on the team's performance relative to previous standards. Study 2 then utilized this methodology to compare a match between two professional sides, played the following season, to assess the extent to which the performance by one team affected that of the other. Comparison of the two teams' performances, for the match they played against each other, identified a drop in relative performance (against previous standards) for both teams on the same performance indicators. This appeared to be due to the match being a close, hard-fought contest particularly in the tackle and around the gain-line. The findings of the two studies suggest an accurate and viable methodology for depicting team performance that is superior to the global measures previously adopted. Presenting teams' current standardized performances (i.e. form) on a single visual scale also has utility for coaches within an applied setting. Future research should further investigate the effect of one team's performance on another through both individual and team outcomes.     

Extending Validity Evidence for Multidimensional Measures of Coaching Competency

This study extended validity evidence for multidimensional measures of coaching competency derived from the Coaching Competency Scale (CCS; Myers, Feltz, Maier, Wolfe, & Reckase, 2006) by examining use of the original rating scale structure and testing how measures related to satisfaction with the head coach within teams and between teams. Motivation, game strategy, technique, and character building comprised the dimensions of coaching competency. Data were collected from athletes (N = 585) nested within intercollegiate men's (g = 8) and women's (g = 13) soccer and women's ice hockey (g = 11) teams (G = 32). Validity concerns were observed for the original rating scale structure and the predicted positive relationship between motivation competency and satisfaction with the coach between teams. Validity evidence was offered for a condensed post hoc rating scale and the predicted relationship between motivation competency and satisfaction with the coach within teams.     

Cardiovascular Measurements on College-Age Smokers and Non-Smokers

Abstract

Thirty-six male college students were measured in six cardiovascular factors as recorded by the Cameron Heartometer. Seventeen of these subjects were smokers and 19 were non-smokers. The purpose of this investigation was to find what residual, as opposed to acute, effects, smoking has on young men. Each subject in both groups was measured in six cardiovascular factors, nine times successively, during his testing period. The smokers abstained from smoking on the day of testing.

The residual effects of smoking in young men, if there be any, cannot be demonstrated in a statistically significant manner in certain cardiovascular factor measurements in the quiet state.     

Determination of football pitch locations from video footage and official pitch markings

The ability to determine a specific location on a football (soccer) pitch from television footage would provide a cost-effective method of obtaining competition-specific information on many professional and international teams. This study presents the accuracy and reliability of a new method of calculating ball location from simulated television coverage and known pitch markings. The coordinates of 99 markers of known location on a football pitch were digitized from video. An intersection point was determined from the equations of two lines that form pitch markings and the relationship from this point to other known pitch coordinates was calculated using a curve-fitting based method. Average error between known and reconstructed measures was 0.21 m for pitch width and 0.11 m for pitch length from a view simulating television coverage. Inter- and intra-rater reliability analyses showed researchers could consistently reconstruct pitch locations to within less than half a metre. The accuracy and reliability of this method will be sufficient for most practical uses in an applied sport environment, although the level of accuracy required will depend on the specific application. This method could be applied to other sports to determine specific locations on a pitch or court or to improve current competition analysis systems.     

Does Displaying the Class Results Affect Student Discussion during Peer Instruction?

The use of personal response systems, or clickers, is increasingly common in college classrooms. Although clickers can increase student engagement and discussion, their benefits also can be overstated. A common practice is to ask the class a question, display the responses, allow the students to discuss the question, and then collect the responses a second time. In an introductory biology course, we asked whether showing students the class responses to a question biased their second response. Some sections of the course displayed a bar graph of the student responses and others served as a control group in which discussion occurred without seeing the most common answer chosen by the class. If students saw the bar graph, they were 30% more likely to switch from a less common to the most common response. This trend was more pronounced in true/false questions (38%) than multiple-choice questions (28%). These results suggest that observing the most common response can bias a student''s second vote on a question and may be misinterpreted as an increase in performance due to student discussion alone.