Half-time Interval Research Articles

The effects of rational and irrational coach team talks on the cognitive appraisal and achievement goal orientation of varsity football athletes

The effects of rational and irrational coach team talks on cognitive appraisal and achievement goal orientation were examined. During the half-time interval of a 60 min football match, 25 male varsity football athletes ( Mage = 20.20; SD ± 1.38 years) received a rational ( n = 13) or an irrational ( n = 12) team talk from a coach. Irrational and rational beliefs were measured before the football match. Task engagement, cognitive appraisal (challenge and threat), and achievement goal orientation (approach and avoidance) regarding second-half football performance were measured following team talk delivery. Athletes in the rational team talk condition reported significantly lower threat appraisal and avoidance goal orientation than athletes in the irrational team talk condition. No significant between-condition differences emerged for challenge appraisal and approach goal orientation. For coaching practice, data suggest that communicating rational or irrational beliefs to football athletes through a half-time team talk will influence appraisal and achievement goal orientation regarding upcoming performance.

Match-play demands of elite youth Gaelic football using global positioning system tracking.

Global positioning systems (GPS) technology has made athlete-tracking a convenient and accepted technique to specify movement patterns and physical demands in sport. The purpose of this study was to examine positional demands of elite youth Gaelic football match-play using portable GPS technology to examine movement patterns and heart rates across match periods. Fifty-six elite youth male Gaelic footballers (age, 15 ± 0.66 years) fitted with portable 4-Hz GPS units were observed during 6 competitive matches (60 minutes). Data provided from the GPS unit included total distance, high-intensity (≥17·km·h(-1)) distance, sprint (≥22 km·h(-1)) distance, and total number of sprints. Heart rate was monitored continuously throughout the games. Players covered a mean distance of 5732 ± 1047 m, and the mean intensity of match-play was 85% of the peak heart rate. There was a significant (p = 0.028) drop in the total distance covered in the second half (2783 ± 599 m) compared with the first half (2948 ± 580 m). In particular, there is a noticeable drop in the distance covered in the third quarter of the game (after half-time), which has implications for re-warming up at the end of the half-time interval. There was a highly significant (p < .001) difference in the distance traveled across the 5 positional groups with midfielders covering the greatest total distance (6740 ± 384 m). The significant differences found with respect to positional groups support the implementation of individual, position-specific strength and conditioning programs.

Warm-up strategies of professional soccer players: practitioners' perspectives

Recent research has challenged the typical pre-match and half-time (HT) interval warm-up (WU) routines currently used by professional soccer players. This study surveyed 2010/11 season WU strategies and their underpinning scientific reasoning and situational factors via an internet-based questionnaire, which was distributed to English Premier League and Championship practitioners, of which 43% responded. The pre-match WU duration was 30.8 (8.2) min, ranging between 15–45 min, and 89% of practitioners administered a WU of ≥ 25 min. Respondents also reported a 12.4 (3.8) min period between the end of the WU and match kick-off. Eighty-nine per cent recognised the physiological benefits of re-WUs during this “down-time” period, with 63% instructing players to engage in such activity. During HT, 58% instructed players to re-WU either on the pitch or within stadia facilities, but “unwillingness of the coach/manager” (42%) and a “lack of time” (63%) were major constraints. Practitioners reported that 2.6 (1.6) min might be available for HT re-WUs. Factors such as match regulations, league policy, and stadia facilities were not generally considered as major barriers to the delivery of WUand re-WU strategies. We suggest that researchers consider the time-demands and barriers faced by practitioners whendeveloping experimental designs to examine WU regimens.

Half-Time and High-Speed Running in the Second Half of Soccer

This study investigated if the quantity of high-speed running (movements >15 km.h(-1) completed in the first 15 min of competitive football matches differed from that completed in the corresponding 15 min of the second half. 20 semi-professional soccer players (age 21.2±3.6 years, body mass 76.4±3.8 kg, height 1.89±0.05 m) participated in the study. 50 competitive soccer matches and 192 data files were analysed (4±2 files per match) using Global Positioning Satellite technology. Data were analysed using 2-way repeated measures ANOVA and Pearson correlations. No differences were found between the first 15 min of each half for the distance completed at high-speed (>15 km.h(-1) or sprinting (>21 km.h(-1), or in the number of sprints undertaken (p>0.05). However, total distance covered was shorter (1st half vs. 2nd half: 1746±220 vs. 1644±224 m; p<0.001) and mean speed lower (1st half vs. 2nd half: 7.0±0.9 vs. 6.6±0.9 km.h(-1); p<0.001) in the first 15 min of the second half compared to the first. The correlations between the duration of the half-time interval and the difference in the high-speed running or sprinting between first and second halves (0-15 min) were very small (r=0.08 [p=0.25] and r=0.04 [p=0.61] respectively). Therefore, this study did not find any difference between the amount of high-speed running and sprinting completed by semi-professional soccer players when the first 15 min of the first and second half of competitive matches were compared The maintenance of high-speed running and sprinting, as total distance and mean speed declined, may be a function of the pacing strategies adopted by players in competitive matches.

Re-examination of the post half-time reduction in soccer work-rate

ObjectivesTo re-examine the work-rate of soccer players immediately after a passive half-time interval with an alternative approach to data reduction and statistical contrasts. DesignTime–motion analysis data (5Hz global positioning system), were collected from 20 elite youth players (age: 17±1 years) during 21 competitive league fixtures (5±3 matches per player). MethodsPhysical performances were categorised into total distance covered, total low-speed running (0–14.9kmh−1) and total high-speed running (15.0–35.0kmh−1). These dependent variables were subsequently time averaged into pre-determined periods of 5-, 15- and 45-min duration, and expressed in relative (mmin−1) terms to allow direct comparisons between match periods of different lengths. During the 15-min half-time interval players were passive (seated rest). ResultsThere was a large reduction in relative total distance covered (effect size – standardised mean difference – 1.85), low-speed running (effect size −1.74) and high-speed running (effect size −1.37) during the opening 5-min phase of the second half (46–50min) when compared to the first half mean (0–45min). When comparing the 51–55 and 56–60-min periods, effect sizes were trivial for relative total distance covered (effect size −0.13; −0.04), low-speed running (effect size −0.10; −0.11) and small/trivial for high-speed running (−0.39; 0.11). ConclusionsUsing a more robust analytical approach, the findings of this study support and extend previous research demonstrating that players work-rate was markedly lower in the first 5-min after a passive half-time interval, although we observed this phenomenon to be transient in nature. Time–motion analysts might re-consider their data reduction methods and comparators to distinguish within-match player work-rate trends.

High-intensity Running Performance in Competitive Soccer Following the Half-time Interval

Previous research suggests that a decrement in sprint and high-intensity running performance is evident in the first 5-10 min of play post a half-time interval. PURPOSE: The aim of the present study was to investigate whether sprint and high-intensity running performance was curtailed during the first 15 minutes of each half, in actual competitive matches, and if factors such as duration of half-time or ambient environmental temperature influenced performance. METHODS: 20 amateur level soccer players (age 21.2 ± 3.6 years, body mass 76.4 ± 3.8 kg, height 1.89 ± 0.05 m) participated in the study. 50 competitive soccer matches were analysed that produced 192 data files. A global positioning satellite system (GPS) was used during matches to assess heart rate, and the distances run at particular speeds ('walk', 0-6; 'jog', 6-12; 'run', 12-15.0; 'fast run', 15.0-18.0; 'fast run', 18.0-21; 'sprint', >21 km.h-1). High- intensity running (HIR) was defined as >15.0 km.h-1. Data (mean±SD) were analysed using a Pearson correlation coefficient, paired t-test (first 15 min of each half) and 2-way ANOVA (half by 5 min interval). RESULTS: No differences in HIR or sprinting (1st: 59.9±45.5 vs 2nd: 55.1±42.4) performed by players were found between the first 15 minutes of each half (P >0.05). HIR distance for 0-5 minutes and 45-60 minutes was 49.2±37.3 and 41.6±32.6 m respectively. Correlations showed length of half time had no relationship with the difference between halves for number of sprints (r = 0.410; P = 0.249), sprint distance (r = 0.04; P = 0.605) and HIR distance (r = 0.08; P = 0.249). Similarly, ambient temperature was not correlated with the difference between halves for number of sprints (r = 0.045; P = 0.545), sprint distance (r = 0.002; P = 0.976) and HIR distance (r = 0.05; P = 0.491). CONCLUSION: The present study demonstrated no difference in high intensity running performed in the first 15 minutes of match play compared to the first 15 minutes of the second half. Length of half time and ambient air temperature have no relationship with the difference in the amount of high intensity running done at the start of match play compared with the first 15 minutes of the second half.

Ball-Sport Endurance and Sprint Test (BEAST90): Validity and Reliability of a 90-Minute Soccer Performance Test

The aim of this study was to determine the validity and reliability of a 90-minute soccer performance test: Ball-sport Endurance and Sprint Test (BEAST90). Fifteen healthy male amateur soccer players participated and attended 5 testing sessions over a 10-day period to perform physiologic and soccer-specific assessments. This included familiarization sessions and 2 full trials of the BEAST90, separated by 7 days. The total 90-minute distance, mean percent peak heart rate (HRpeak), and estimated percent peak oxygen uptake of the BEAST90 were 8,097 ± 458 m, 85 ± 5% and 82 ± 14%, respectively. Measures obtained from trial 1 and trial 2 were not significantly different (p > 0.05). Reliability of measures over 90 minutes ranged from 0.9-25.5% (% typical error). The BEAST90 protocol replicated soccer match play in terms of time, movement patterns, physical demands (volume and intensity), distances, and mean and HRpeak values, as well as having an aerobic load similar to that observed during a soccer match. Reproducibility of key physical measures during the BEAST90 were mostly high, suggesting good reliability. The BEAST90 could be used in studies that wish to determine the effects of training or nutritional interventions on prolonged intermittent physical performance.

Soccer-Specific Fatigue and Eccentric Hamstrings Muscle Strength

Epidemiologic findings of higher incidences of hamstrings muscle strains during the latter stages of soccer match play have been attributed to fatigue. To investigate the influence of soccer-specific fatigue on the peak eccentric torque of the knee flexor muscles. Descriptive laboratory study. Controlled laboratory environment. Ten male professional soccer players (age = 24.7 +/- 4.4 years, mass = 77.1 +/- 8.3 kg, Vo(2max) = 63.0 +/- 4.8 mL x kg(-1) x min(-1)). Participants completed an intermittent treadmill protocol replicating the activity profile of soccer match play, with a passive halftime interval. Before exercise and at 15-minute intervals, each player completed isokinetic dynamometer trials. Peak eccentric knee flexor torque was quantified at isokinetic speeds of 180 degrees x s(-1), 300 degrees x s(-1), and 60 degrees x s(-1), with 5 repetitions at each speed. Peak eccentric knee flexor torque at the end of the game (T(300eccH105) = 127 +/- 25 Nm) and at the end of the passive halftime interval (T(300eccH60) = 133 +/- 32 Nm) was reduced relative to T(300eccH00) (167 +/- 35 Nm, P < .01) and T(300eccH15) (161 +/- 35 Nm, P = .02). Eccentric hamstrings strength decreased as a function of time and after the halftime interval. This finding indicates a greater risk of injuries at these specific times, especially for explosive movements, in accordance with epidemiologic observations. Incorporating eccentric knee flexor exercises into resistance training sessions that follow soccer-specific conditioning is warranted to try to reduce the incidence or recurrence of hamstrings strains.

The influence of soccer-specific activity on the kinematics of an agility sprint

The aim of this study was to investigate the influence of soccer-specific fatigue on the kinematics of an agility sprint. Ten male professional soccer players (age 24.7±4.4 years, body mass 77.1±8.3 kg) completed an intermittent treadmill protocol replicating the activity profile of match-play, comprising two 45-min halves separated by a 15-min passive half-time interval. Pre-exercise and at 15-min intervals each player completed an agility sprint that consisted of a 180° cutting manoeuvre. Knee joint kinematics in the frontal and sagittal planes were determined for both the support and turning leg using a nine-camera automated motion analysis system operating at 200 Hz. During the penultimate foot contact, knee kinematics were characterized by joint flexion and increased varus alignment. Knee flexion at touchdown decreased significantly (P<0.05) as a function of exercise duration from 57.4±15.5° before exercise to 37.0±5.9° at the end of the second half. The range of joint movement during the knee flexion phase increased significantly during the first half (T 45=66.6±18.2°) and remained elevated during the second half (T 75=66.4±18.1°; T 90=65.7±20.4°; T 105=70.2±19.4°) relative to pre-exercise values (51.8±18.8°). During the final foot contact, knee kinematics were also characterized by flexion and increased varus alignment. Knee flexion at touchdown decreased during each half, with the knee angle at the end of the first half (30.6±7.0°) significantly (P=0.02) straighter than before exercise (39.5±6.3°), and significantly straighter at the end of the second half (30.2±2.9°) than after the half-time interval (37.7±7.8°) or before exercise. The range of knee flexion during ground contact increased significantly during each half. The range of knee varus during flexion changed from a varus displacement during the first 15 min to a valgus displacement thereafter. Peak valgus observed at the end of each half (T 45=4.7±7.9°; T 105=6.9±7.4°) was significantly (P<0.05) greater than before exercise. The range of valgus movement during knee extension was greatest following the passive half-time interval (T 60=6.2±7.3°), and tended to increase throughout the second half. Prolonged exposure to soccer-specific intermittent exercise therefore induced changes in knee kinematics that may have implications for injury incidence. The increased varus alignment and time-dependent decrease in knee flexion at touchdown represent two potential mechanisms for increased injury risk.

Effect of Inhaling Canned Oxygen on Core Temperature in Soccer Players under Hot Weather Conditions

PURPOSE: The aim of this investigation was to study the effect of inhaling canned oxygen on the core body temperature (Tc) during a soccer match played under hot weather conditions. METHODS: Tc was studied during the half time interval and the second half of an official game of the Argentine Football Association (AFA), in 8 professional male field players (age = 24.0 ± 2.8 yr, BMI = 23.4 ± 1.0 kg/m2; mean ± SD). The weather conditions during the test were: temperature = 35° C, humidity = 75%. At the end of the first half of the game, the players were randomly assigned to 1 of 3 treatment groups: group 1 inhaled canned oxygen (n = 3); group 2 inhaled placebo (n = 3); group 3 served as control (n = 2, as 1 of the 3 initial players left). Both the concentrated oxygen (95%) and the placebo were supplied during 4 s using a spray can. Tc was assessed at the end of the first half, and at the beginning, in the middle, and at the end of the second half of the game, by means of an ingestible telemetry sensor, and was monitored with a miniaturized ambulatory data recorder. All the players were hydrated in the half time interval and in the middle of the second half of the game. Treatment comparisons were made based on a linear mixed-effects model with repeated measures, with Individual as a random factor, the baseline value as a covariable, and a first-order autoregressive error structure. RESULTS: The ad hoc test did not indicate significant differences between the players treated with oxygen and the rest (−0.52° C, p>0.05; 95% CI: −1.18 to 0.13). The F-test did not show significant differences between treatments (37.94°, 38.71° and 38.22° C, p>0.05; groups 1, 2 and 3, respectively). In the half time interval, the group treated with oxygen revealed the greatest decrease in Tc (1.84°, 1.03° and 0.87° C). However, this group showed the greatest increase in the first part of the second half of the game (1.55°, 0.82° and 0.35° C). CONCLUSIONS: There were not clear evidences that inhaling canned oxygen influenced on Tc throughout the test. Possible short-time effects should be further investigated.

Inspiratory Muscle Fatigue in Male University Rugby Players

Rugby Union is a team based invasion game played on a grass field between two teams of 15 players. The game is played over two 40 minute periods and involves a high level of physiological strain. PURPOSE: The aim of this study was to investigate the change in Maximal Inspiratory Pressure (MIP) that occurs in University players as a result of a game of Rugby Union. METHODS: Thirty male Loughborough University rugby union players (Age 20.1 + 0.82 years, Stature 1.84 + 0.07m, Mass 92.4 + 10.1kg from the first and second team squads played a fully officiated 80 minute 'training' game against each other. Maximal Inspiratory Pressure (MIP) as measured at the mouth (Micro medical-RPM) was taken post warm up but before the game (PRE), during the half time interval (HALF) and again post game (POST). Players were described as either forwards (FOR) or backs (BACK) depending upon their playing position. All players had previously undergone a familiarisation process with the instrumentation, the testing process and the MIP measurements themselves. RESULTS: A repeated measures ANOVA (SPSSv15.0.1) showed there to be significant variability within the data set (p>0.05). Post hoc pairwise comparisons showed the difference was for all cases (PRE v HALF, PRE v POST and HALF v POST). This difference remained when the group was split for position played (FOR PRE v FOR POST and BACKS PRE v BACKS POST) however, there were no differences present when the playing positions were compared against each other (PRE FOR v PRE BACKS and POST FOR v POST BACKS. Bland and Altman 95% limits of agreement were also calculated for the player position comparison (16.1 + 68.3 mmH2O) as well as the PRE-Post comparison (-22.4 + 40.1 mmH2O). MIP scores were not significantly correlated against Body Mass (r2 0.0004) or Stature ( r2 0.0003). CONCLUSIONS: Rugby players show a reduction in MIP post-game which may be due to the physiological strain imposed by the demands of the game. There is a large degree of variability in MIP between individuals regardless of their playing position or physical dimensions. In order to ascertain whether this reduction in MIP can be attenuated this study should be repeated following a period of Inspiratory muscle training.

The Influence of Soccer-Specific Fatigue on Peak Isokinetic Torque Production of the Knee Flexors and Extensors

Background Epidemiological findings of higher muscular thigh strain injury incidence during the latter stages of soccer match play have been attributed to fatigue. Hypothesis Soccer-specific fatigue will significantly reduce peak isokinetic torque of the knee flexors and extensors. Study Design Descriptive laboratory study. Methods Ten male professional soccer players (mean age, 24.7 ± 4.4 years; body mass, 77.1 ± 8.3 kg; maximum oxygen consumption [VO2 max], 63.0 ± 4.8 mlVkg/min) completed an intermittent treadmill protocol replicating the activity profile of match Play. Before exercise and at 15-minute intervals, each player completed 1 of 2 randomized isokinetic dynamometer protocols. The first protocol quantified peak concentric knee extensor and flexor torque, while the second quantified peak concentric and eccentric knee flexor torque at isokinetic speeds of 180, 300, and 60 deg/s (3.14, 5.25, and 1.05 rad/s) with 5 repetitions at each speed. Results Concentric knee extensor and flexor peak torque were maintained throughout the duration of the exercise protocol, irrespective of movement speed. However, peak eccentric knee flexor torques at the end of the game (T300eccH105 = 127 ± 25 N.m) and at the end of the passive half-time interval (T300eccH60 = 133 ± 32 N.m) were significantly reduced relative to the first 15 minutes (T300eccH00 = 167 ± 35 N·m, P < .01; T300ecoH15 = 161 ± 35 N·m, P = .02). Conclusion Eccentric knee flexor strength decreases as a function of time and after the half-time interval. Clinical Relevance This suggests a greater risk of injuries at these specific times, especially for explosive movements, in accord with epidemiological observations.

A continuous mental task decreases the physiological response to soccer-specific intermittent exercise

Background:Epidemiological findings of higher injury incidence during the latter stages of soccer match-play have been attributed to fatigue.Objective:To examine the interaction of physical and cognitive responses during soccer-specific intermittent exercise.Method:Ten...

The Determinants of Soccer Player Substitutions

This paper analyzes the pattern of player substitutions during a soccer match using data from the Spanish First Division in the 2004—2005 season. We use an inverse Gaussian hazard model to analyze the first substitutions on each team taking place either at halftime or in the second half of the game. The results show that the most important factor explaining the timing of the first player substitutions on a team is the score as it stands prior to the substitution. Furthermore, defensive substitutions are made later in the match than offensive substitutions. We also found some evidence that home teams make more substitutions than visiting teams in the halftime interval.

The influence of soccer-specific fatigue on functional stability

Objective To quantify the influence of soccer-specific fatigue on functional stability. Participants and design Ten male semi-professional soccer players completed a 90 min treadmill protocol replicating the activity profile of match-play with a passive 15 min half-time interval. Main outcome measures At 15 min intervals players completed a 30 s single-legged balance task on an unstable platform. Balance performance was quantified as a stability index and the mean deflection of the platform. Results There was no significant ( P>0.05) main effect for exercise duration in the stability index, suggesting that balance performance was maintained throughout the simulated match. However, the mean deflection of the platform was significantly ( P<0.05) shifted toward anterior displacement during the last 15 min of each half. Conclusion A change in balance strategy was evident during the latter stages of match-play, which may increase injury risk. It is recommended that soccer players perform proprioception training in the rested and exercised state to further develop neuromuscular control.

Progressive Decrease in Dynamic Postural Control During Simulated Soccer Match-Play

This study investigated the cumulative effect of soccer-specific fatigue on dynamic posturography. Professional soccer players (N = 8) completed a treadmill protocol, which comprised two 45-minute exercise periods separated by a 15-minute interval (simulation of half-time). A 15-minute activity profile was developed, which was repeated six times in total. The 15-minute activity profile comprised 195 discrete bouts of exercise, producing a change in speed every ~6 seconds. Within this activity profile, seven movement speeds were included. Center of gravity displacement tended to increase as a function of exercise duration during each simulated half, with second half performance typically impaired more than in the first half. This trend was evident for total, medio-lateral and anterio-posterior displacement. During the plantar rotation trial, the passive half-time interval was observed to significantly increase medio-lateral displacement of the ankle. The intermittent activity profile of soccer match-play induced a significant deterioration in dynamic postural response as exercise progressed. Reduction in joint stability predisposed the ankle joint complex to sprain injury during the latter stages of match-play. Furthermore, a passive half-time strategy predisposed the ankle joint to injury during the early stages of the second half. [For baseball. Fatigue that occurs from pitching when not conditioned specifically for pitching, increases the likelihood of injury at the end of the pitching bout. When no activity occurs between-innings, the sudden resumption of violent pitching exercise also increases the likelihood of joint injuries (e.g., hamstrings, ankles, elbows). Thus, increasing specific pitching fitness and maintaining an active recovery during innings should reduce the likelihood of injury during a game.]

Impact of the 10-Meter Rule Change on Professional Rugby League: Implications for Training

Rudi Meir, MA, CSCS; Paul Colla, BHMS; and Cynthia Milligan, BHMSSchool of Exercise Science and Sport ManagementSouthern Cross UniversityKeywords: rugby league; time and motion analysis; training.WHEN DEVELOPING A SPORT-specific training program for ateam, the strength and condition-ing coach needs a detailed knowl-edge and understanding of the de-mands placed on participantsduring competition. Observationusing time and motion analysis isa practical alternative to more so-phisticated procedures that canprovide details relating to the typeof match play activities performed,how often they are performed, andfor what period of time. In addi-tion, the frequency and ratio ofwork to rest, overall distance cov-ered, and intensity of effort—andtherefore the dominant energysystems used—can be identifiedand estimated.Rugby league football is ateam sport played over two 40-minute halves separated by a 10-minute half-time interval. A teamcomprises 13 players with teampositions broadly defined as eitherforwards (i.e., all players involvedin the scrum,

Assessment of Faecal Output in Geese

(1) The faecal output of geese (Anseriformes) is often measured in the course of bioenergetic or flock management studies. The first objective of this investigation was to examine the influence of method on the field assessment of defaecation rate in greater snow geese (Chen caerulescens atlantica (Linnaeus)). (2) We introduce the 'hourly block method', the only one which produced unbiased estimates of this parameter: 'direct interval estimate' and 'short-cut' methods (in particular Owen's half-time interval) were found to produce biased and/or high variance estimates and were deemed unreliable in most circumstances. Computer modelling confirmed these conclusions. (3) The second objective of the investigation was to identify the sources of bias and variance affecting dropping-count estimates obtained in sample plots. (4) The observation method chosen (observer standing or crouched, observer single or paired) had a great effect on the size of the bias encountered. Variance due to observer, plot and habitat was also assessed. (5) Suggstions to stabilize and/or remove causes of bias and to improve the precision of dropping-count estimates are given.