Examining the Relationship Between Purposeful Heading in Soccer and Computerized Neuropsychological Test Performance

The purpose of this study was to determine if a relationship exists between purposeful heading in soccer and neuropsychological test performance. Automated Neuropsychological Assessment Metrics throughput scores were derived on seven subset variables that measure a variety of neurocognitive abilities. Simple Spearman's rank correlations were calculated between headers per game (HPG) and the criterion variables. Interestingly, math processing speed (Spearman's rho = .160) and continuous performance test #2 (rho = .124) had small but significant correlations; both showed improvement in performance pre- to postseason. There were no significant correlations between HPG and the other five variables. This study found no detrimental relationship between the number of purposeful headers and the neurocognitive measures in this population.     

Critical velocity: a predictor of 2000-m rowing ergometer performance in NCAA D1 female collegiate rowers

The aims of this study were to examine the use of the critical velocity test as a means of predicting 2000-m rowing ergometer performance in female collegiate rowers, and to study the relationship of selected physiological variables on performance times. Thirty-five female collegiate rowers (mean ± s: age 19.3 ± 1.3 years; height 1.70 ± 0.06 m; weight 69.5 ± 7.2 kg) volunteered to participate in the study. Rowers were divided into two categories based on rowing experience: varsity (more than 1 year collegiate experience) and novice (less than 1 year collegiate experience). All rowers performed two continuous graded maximal oxygen consumption tests (familiarization and baseline) to establish maximal oxygen uptake (VO(2max)), peak power output, and power output at ventilatory threshold. Rowers then completed a critical velocity test, consisting of four time-trials at various distances (400 m, 600 m, 800 m, and 1000 m) on two separate days, with 15 min rest between trials. Following the critical velocity test, rowers completed a 2000-m time-trial. Absolute VO(2max) was the strongest predictor of 2000-m performance (r = 0.923) in varsity rowers, with significant correlations also observed for peak power output and critical velocity (r = 0.866 and r = 0.856, respectively). In contrast, critical velocity was the strongest predictor of 2000-m performance in novice rowers (r = 0.733), explaining 54% of the variability in performance. These findings suggest the critical velocity test may be more appropriate for evaluating performance in novice rowers.     

Performance determinants of fixed gear cycling during criteriums

Nowadays, fixed gear competitions on outdoor circuits such as criteriums are regularly organized worldwide. To date, no study has investigated this alternative form of cycling. The purpose of the present study was to examine fixed gear performance indexes and to characterize physiological determinants of fixed gear cyclists. This study was carried out in two parts. Part 1 (n?=?36) examined correlations between performance indexes obtained during a real fixed gear criterium (time trial, fastest laps, averaged lap time during races, fatigue indexes) and during a sprint track time trial. Part 2 (n?=?9) examined correlations between the recorded performance indexes and some aerobic and anaerobic performance outputs (VO_2max, maximal aerobic power, knee extensor and knee flexor maximal voluntary torque, vertical jump height and performance during a modified Wingate test). Results from Part 1 indicated significant correlations between fixed gear final performance (i.e. average lap time during the finals) and single lap time (time trial, fastest lap during races and sprint track time trial). In addition, results from Part 2 revealed significant correlations between fixed gear performance and aerobic indicators (VO_2max and maximal aerobic power). However, no significant relationship was obtained between fixed gear cycling and anaerobic qualities such as strength. Similarly to traditional cycling disciplines, we concluded that fixed gear cycling is mainly limited by aerobic capacity, particularly criteriums final performance. However, specific skills including technical competency should be considered.     

Epistemology and the Use of the .05 Level of Significance: A Rebuttal to Inductionism

In the first part of this study, the football potential of 67 football players was predicted from their scores on a football-potential test. The test battery consisted of motor ability items as well as football skill items. Substantial correlations were obtained between most test items and the test criterion, the sum of T scores. Size, as depicted by McCloy's classification index (C.I.), had a negative, nonsignificant correlation with the criterion. The discriminative power of the battery was evidenced by the highly significant correlation between the test criterion and the coaching staff's ranking of individual players (rho = .840). It was concluded that athletic potential in football can be predicted by testing. In the second part of the study, football teams from three different strata of competition were evaluated on the basis of the test battery. The battery substantiated a step-wise progression between the teams on most items, with significant differences being noted. The test showed validity, in that the test criterion (the sum of T scores) was significantly different between the teams.     

Assessment of decision-making performance and in-game physical exertion of Australian football umpires

Abstract

The aim of this study is to investigate the effects of in-game physical exertion on decision-making performance of Australian football umpires. Fifteen Australian football umpires (M_age = 36, s = 13.5 years; M_{games umpired} = 235.2, s = 151.3) volunteered to participate in the study. During five competitive Australian football pre-season games, measures of in-game physical exertion (blood lactate levels, global positioning system [GPS]) and decision-making performance (video-based test) were obtained. There were no significant correlations between physical exertion in a particular quarter and decision-making performance in either the same quarter or any other quarter. Video-based decision-making performance was effected by time in game χ²(3) = 24.24, P = 0.001, with Quarter 4 performance significantly better than both Quarter 2 and Quarter 3. In-game physical exertion (blood lactate) significantly decreased over the course of the game χ²(3) = 11.58, P = 0.009. Results indicate no definable link between in-game physical exertion and decision-making performance. It is, however, presumed that decision-making performance may be affected by the time or context of the game. Future research is warranted to explore the relationship between physical exertion and decision-making performance to potentially inform Australian football umpire training programmes that replicate in-game physical and decision-making demands.     

Choice of sprint start performance measure affects the performance-based ranking within a group of sprinters: which is the most appropriate measure?

Sprint start performance has previously been quantified using several different measures. This study aimed to identify whether different measures could influence the performance-based ranking within a group of 12 sprinters, and if so, to identify the most appropriate measure. None of the 10 performance measures ranked all sprinters in the same order; Spearman's rho correlations between different block phase measures ranged from 0.50 to 0.94, and between block phase measures and those obtained beyond block exit from 0.66 to 0.85. Based on the consideration of what each measure quantifies, normalised average horizontal external power was identified as the most appropriate, incorporating both block velocity and the time spent producing this velocity. The accuracy with which these data could be obtained in an externally valid field setting was assessed against force platform criterion data. For an athlete producing 678 +/- 40 W of block power, a carefully set-up manual high-speed video analysis protocol produced systematic and random errors of +5 Wand +/- 24 W, respectively. Since the choice of performance measure could affect the conclusions drawn from a technique analysis, for example the success of an intervention, it is proposed that external power is used to quantify start performance.     

Physiological variables and performance markers of serving soldiers from two "elite" units of the British Army

The aim of this study was to compare selected physiological variables and performance markers of soldiers from two "elite" units of the British Army. Ten soldiers from each of the two units were recruited for this study (n = 20). All participants completed three tests while carrying a 20 kg backpack load: (1) a maximal treadmill test using the Bruce protocol; (2) a 2 mile backpack run test specific to Unit A on a consistently flat tarmac road; and (3) a 29 km time-trial over hilly terrain typical of a mountainous area used by Unit B for performance assessment. Heart rate, maximal blood lactate concentration and performance (run time) were assessed during all three tests, with peak oxygen uptake also being measured during the maximal treadmill test. Measurements of anthropometry, isokinetic strength and mental toughness (MT48) were also recorded. There were no significant differences in terms of performance markers between the units (P > 0.05). Performance on the maximal treadmill test correlated with performance on the 2 mile backpack run test (r = -0.57) and 29 km time-trial (r = -0.66). Performance on the 2 mile backpack run test in turn correlated with 29 km time-trial performance (r = -0.77), accounting for 59% of the variance. In conclusion, the maximal treadmill test and the 2 mile backpack run test are useful indicators of performance on the arduous hill march and could be employed in the screening and selection of potential recruits.     

Prediction of performance by heart rate-derived parameters in recreational runners

We investigated whether heart rate (HR)-derived parameters are accurate performance predictors in endurance recreational runners. One hundred thirty recreational athletes completed an incremental running test (4´running + 1´rest). After each stage, we recorded HR, % of maximum HR (%HRmax), and blood lactate. We also assessed HR after each recovery period, and calculated lactate and HR recovery thresholds and HR deflection point. We tested these parameters for associations with running performance, as measured by peak treadmill speed (PTS) and personal best International Association of Athletics Federations (IAAF) score. The %HRmax at 14.5 km·h^?1 correlated with PTS (r = ?0.92), and IAAF score (rho = ?0.80). The magnitudes of the correlations of lactate-related parameters with PTS (|r| = 0.84 to 0.86) or IAAF score (|rho| = 0.70 to 0.77) in absolute values were slightly lower. The correlations detected between other HR-derived parameters and running performance were weaker (|r or rho| = 0.24 to 0.70). Regression models identified %HRmax at 14.5 km·h^?1 as the strongest predictor of both PTS (β = ?0.72) and IAAF score (β = ?0.72). Consequently, tests based on %HRmax may provide a non-invasive and inexpensive alternate method for predicting the performance of these athletes.     

The role of anthropometric characteristics in modern pentathlon performance in female athletes

In order to determine the role of body build characteristics in modern pentathletes, 65 female participants at the IXth World Modern Pentathlon Championships, 1989 (Wiener Neustadt, Austria) were investigated. Of these, 54 participated in the competition; the other 11 were reserves. Their mean ( + S.D.) age was 22.34 ± 3.97 years (range 16.08–32.58 years). Anthropometric characteristics (body mass, lengths, breadths, girths and skinfolds), somatotype and body composition estimates were determined. Compared with other female athletes (e.g. swimmers, runners, fencers), the elite modern pentathletes were rather tall (x = 168.1 cm) and, as indicated by the body mass index (x = 21.6), they had a high mass relative to their stature. Based on skinfolds, body fat was estimated as 16%, and anthropometrically determined somatotype was on average 2.5–3.9–2.8. The relationship between the athletes’ anthropometric characteristics and modern pentathlon performance was investigated by means of Pearson zero‐order correlations between the physical traits and the competitive performance scores. Significant correlations were found mainly for the ‘fat’ variables, such as skinfolds, percent fat and the endomorphy component, r varying from –0.34 to –0.58, which indicated an inverse relationship between the amount of fatness and modern pentathlon performance. To investigate this relationship further, Pearson zero‐order correlations were calculated between the respective factor scores, derived from a rotated factor pattern (Varimax) carried out on selected somatic variables, and the performance scores. The results demonstrated that, in relation to anthropometric characteristics, modern pentathlon performance in females is mainly associated with the ‘fat development’ factor, and to a lesser degree with the ‘bone‐muscle development’ factor. Variables representing linearity of physique seem to be unrelated to modern pentathlon performance. Stepwise regression analysis revealed that 42.4% of the variance in modern pentathlon performance can be explained by the following anthropometric variables: sum of 10 skinfolds, biacromial breadth and humerus diameter. To obtain a high level of modern pentathlon performance, it would seem that a female athlete must above all have a low level of body fatness and, to a lesser degree, a relatively high level of lean body mass.     

The Decline in American Children's Fitness Levels

Abstract

Three anthropometric and eight physical performance measures selected by the author were related by correlational methods to the performance of 87 secondary school boys in the running hop, step, and jump. All variables showed a significant relationship with the criterion beyond the .05 level of confidence. The criterion could be employed as a measure of motor ability since three of the highest single-variable correlations with the criterion were measures that are known predictors of motor ability: the running broad jump (r = .859), 50-yd. dash (r = .815), and standing broad jump (r = .778). Three selected combinations of measures yielded multiple correlations with the criterion which were significant beyond the .01 level of confidence. A regression equation developed from the optimal set of variables that was considered to be feasible for administration in school systems consisted of two items from the Youth Fitness Test Manual: the standing broad jump and the 50-yd. dash.     

Familial aggregation in physical activity.

The purposes of this study were to (a) examine the stability and consistency of the Caltrac accelerometer (Hemokinetics, Madison, WI) and an activity record to assess physical activity in children and adults (Experiment 1), and (b) to determine if there is a relationship between parents and their children in physical activity level (Experiment 2). Thirty 5-9-year-old children and their biological parents wore Caltrac accelerometers for three consecutive days (including one weekend day). At the same time, parents completed a Caltrac Activity Record (CAL REC) for themselves and their child. Dependent variables were counts per day for the Caltrac and minutes of light activity and activity for the CAL REC. Between-day correlations for the Caltrac ranged from r = .73 to .87 for the parents (p less than .001) and from r = .38 (p less than .04) to .79 (p less than .001) for the children. An analysis of variance with repeated measures indicated no significant differences for the Caltrac between days for parents and children. Between-day correlations for CAL REC ranged from r = .67 to .91 (p less than .05) for parents and r = .36 to .72 (p less than .05) for children, and there were no significant differences between days. In Experiment 2, chi 2 analyses were used to examine familial resemblance in physical activity. Using the Caltrac, familial resemblance occurred in 67% (father and child) and 73% (mother and child) of the families. Using the CAL REC, familial aggregation was present in 70% (father and child) and 66% (mother and child) of the families.(ABSTRACT TRUNCATED AT 250 WORDS)     

The Relationship Between Running Economy and Biomechanical Variables in Distance Runners

In this study, we analyzed the relationship between running economy (RE) and biomechanical parameters in a group running at the same relative intensity and same absolute velocity. Sixteen homogeneous male long-distance runners performed a test to determine RE at 4.4 m.s^-1, corresponding to 11.1% below velocity at the ventilatory threshold. We found significant correlations between RE and biomechanical variables (vertical oscillation of the center of mass, stride frequency, stride length, balance time, relative stride length, range of elbow motion, internal knee, ankle angles at foot strike, and electromyographic activity of the semitendinosus and rectus femoris muscles). In conclusion, changes in running technique can influence RE and lead to improved running performance.     

Relationship between Achievement in Reading and Achievement in Selected Motor Skills in Elementary School Children

Abstract

The study was designed to determine the relationships between achievement in reading and achievement in selected motor skills for children in grades 1, 3, 5. The Iowa tests of basic skills were used to determine reading achievement and the Johnson motor achievement battery was employed to measure achievement in selected motor skills. The Pearson product-moment coefficient of correlation was applied to compute the relationships between the reading and motor achievement variables. The subjects were divided into three reading achievement levels and Scheffe's method of comparing pairs of means from a two-way analysis of variance table was employed to determine if the achievement differences in the motor skills tests were significant. The following conclusions were drawn: a) Highly significant correlations were found to exist between achievement in reading and the throw and catch test and achievement in reading and the zig-zag run test; b) Little or no consistent relationship existed between achievement in reading and the kicking test or the jump and reach test; c) Significant differences among the selected reading levels were found for the throw and catch test and the zig-zag run test; d) Few significant differences among the selected reading levels were found for the kicking test and for the jump and reach test.     

Reliability and Validity of a New Physical Activity Self-Report Measure for Younger Children

The purpose of this study was to assess the test–retest reliability and validity of a new Youth Physical Activity Self-Report measure. Heart rate and direct observation were employed as criterion measures with a sample of 79 children (aged 7–9 years). Spearman's rho (ρ) correlation between self reported activity intensity and heart rate was .87 for weekday and .795 for weekend; the correlation between self-reported activity duration and duration as measured by heart rate were .837 and .684 for weekday and weekend, respectively. These correlations fell when recalled inactivity was excluded from analysis. A correlation of ρ = .557 was found between self-reported activity intensity and direct observation. Results establish support for the self-report measure as an effective tool for measuring the previous day physical activity of younger children.     

Ability of test measures to predict competitive performance in elite swimmers

The purpose of this study was to quantify the relationship between changes in test measures and changes in competition performance for individual elite swimmers. The 24 male and 16 female swimmers, who were monitored for 3.6 years (s = 2.5), raced in a major competition at the end of each 6-month season (3.6 competitions, s = 2.2). A 7 x 200-m incremental swimming step-test and anthropometry were conducted in up to four training phases each season. Correlations of changes in step-test and anthropometry measures between training phases and seasons with changes in competition performance between seasons were derived with repeated-measures mixed-modelling and linear regression. Changes in competition performance were best tracked by changes in test measures between taper phases. The best single predictor of competition performance was skinfolds for females (r = -0.53). The best predictor from the step-test was stroke rate at a blood lactate concentration of 4 mmol x l(-1) (females: r = 0.46; males: r = 0.41); inclusion of the second-best step-test predictor in a multiple linear regression improved the correlations (females: r = 0.52 with speed in the seventh step included; males: r = 0.58 with peak lactate concentration included). In conclusion, a combination of fitness and technique factors is important for competitive performance. The step-test is a useful adjunct in a swimmer's training preparation for tracking large changes in performance.     

Rhythmicity and Preperformance Ritual: Stabilizing a Flexible System

Abstract

The purpose of this study was to determine: (a) if preperformance behaviors display a consistent rhythm across disparate activities; and (b) the relationship of periodicity for such preperformance routines to successful performance. Seven male volunteers were subjects for this study. Each subject had an established ritual for golf putt, basketball free throw, and tennis serve. Data were collected with a motion-analysis system and video camera while the subjects performed each activity. Dependent measures were types of preperformance behaviors, absolute timing of behaviors, relative timing of behaviors, differences in relative times across activities, and successful performance, and mechanical variables related to performance. Analysis of variance (Subject x Activity) indicated significant main effects and interactions for absolute and relative timing of behaviors. Significant correlations were determined to exist between relative time and success, and differences were found between relative times across activity and successful performance. It was concluded that rituals result from endogenous rhythms and that stable periodicity of behaviors across activities promotes successful performance.     

Effects of confidence and anxiety on flow state in competition

Abstract

Confidence and anxiety are important variables that underlie the experience of flow in sport. Specifically, research has indicated that confidence displays a positive relationship and anxiety a negative relationship with flow. The aim of this study was to assess potential direct and indirect effects of confidence and anxiety dimensions on flow state in tennis competition. A sample of 59 junior tennis players completed measures of Competitive State Anxiety Inventory-2d and Flow State Scale-2. Following predictive analysis, results showed significant positive correlations between confidence (intensity and direction) and anxiety symptoms (only directional perceptions) with flow state. Standard multiple regression analysis indicated confidence as the only significant predictor of flow. The results confirmed a protective function of confidence against debilitating anxiety interpretations, but there were no significant interaction effects between confidence and anxiety on flow state.     

Change-of direction deficit in elite young soccer players

Change-of-direction (COD) ability is an essential physical component for soccer. This study examined the relationships between conventional speed–power assessments and COD performance in elite young soccer players. Twenty-five under-20 male players from the same club (age: 17.6?±?0.8 years, height: 178.1?±?6.7?cm, body mass [BM]: 72.2?±?7.9?kg) performed sprint speed tests, vertical jumps, loaded jump squats, half squats, and Zigzag COD assessments. Moreover, the COD deficit was calculated as the difference between 20-m sprint velocity and Zigzag COD test velocity. A Pearson correlation analysis was used to determine the correlations between Zigzag COD performance and COD deficit with speed and power outputs. Although no significant relationships between speed–power variables and COD ability were present, there were still strong positive correlations between traditional neuromechanical measures and COD deficit. Briefly, it seems that higher performances in speed and power tests are not necessarily related to better performances in specific COD maneuvers. Therefore, it is recommended that coaches and technical staff include specific COD drills in soccer player routines to optimize the transference from speed and power capacities to specific COD performance.     

Effect of carrying different military equipment during a fatigue test on shooting performance

This study investigated the effect of a 3-km walking test (3kWT) carrying different military equipment on shooting performance, rating of perceived exertion (RPE), heart rate (HR), and test time. The relative combat wear and backpack weight (as percentage of soldier’s body weight [%BW]) was reported and, along with HR, its relationship to marksmanship variables was tested. Thirty-nine Spanish Army males walked as fast as possible to complete the 3kWT in the following conditions in a randomized order: unloaded walking; wearing the combat uniform; and carrying the combat uniform plus combat backpack. A shooting test was completed before and after the 3kWT. The HR and RPE were evaluated. The marksmanship variables and HR were analysed using a two-way repeated measures ANOVA, and a repeated ANOVA was also used for 3kWT completion time and HR reserve analysis. Correlation analyses were performed between the equipment’s weight, HR, and marksmanship variables. The results showed that shooting score decreased after the 3kWT in both load conditions (p?r?=??0.35; p?=?0.04) and cleanness triggering (r?=?0.37; p?=?0.03). Correlations between HR and shooting variables were non-significant. In conclusion, wearing the Spanish Army combat wear and backpack resulted in shooting performance degradation. Furthermore, fatigue and RPE increased and this could decrease physical marksmanship and performance capacity in combat situations.     

Relationships between rigging set-up, anthropometry, physical capacity, rowing kinematics and rowing performance

The general aim of this study was to examine the relations between rigging set up, anthropometry, physical capacity, rowing kinematics and rowing performance. Fifteen elite single scullers participated in the experiment. Each sculler's preferred rigging set-up was quantified using measurements that included oar length, inboard, span, gearing ratio, swivel-seat height, footstretcher-seat height and distance, and footstretcher angles. Rowing performance was assessed using 2000 m race times from the Australian National Selection trials. Selected anthropometric, physical capacity and kinematic variables were also quantified. Several rigging variables were significantly correlated with each other, and with various anthropometric, physical capacity and kinematic variables. The individual variables that had the highest correlations with race time were 2 km ergometer time (r=0.90), mass (r=-0.87), height (r=-0.86), oar length (r = -0.85) and strength (r = -0.84). Overall results of this study indicated that the fastest rowers tend to be the largest and strongest, and that these larger body dimensions are reflected in the choice of rigging settings. Rigging set-up by itself should not be considered to be a primary determinant of rowing performance, but rather a consequence of faster rowers being larger and stronger and scaling their rigging set-up accordingly. To maximise rowing performance it appears important to tune the rigging of the boat to match the rower's size and strength.