Grip strength measurement in competitive ten-pin bowlers

BACKGROUND: In an attempt to find a more specific grip strength test for bowlers, the conventional grip strength test was modified such that only the fingers used in holding the ball are tested. The objective of this study was to assess the test-retest reliability of this modified bowling grip strength test, to assess the agreement between the bowling and the conventional grip strength tests, and to examine the correlation between the modified test and bowling performance in competitive bowlers. METHODS. EXPERIMENTAL DESIGN: This research was conducted in two parts, each with a different study sample. Study I was a cross-sectional study to assess the correlation between the bowling grip strength and the bowling score. Study II was a comparative study to obtain the test-retest reliability for both the bowling and conventional grip strength tests, and to assess the agreement between the two tests. Setting and subjects: for study I, the subjects were 39 members (26 males and 13 females) of the Singapore National Ten-Pin Bowling Training Squad. Bowling grip strength was measured within one month prior to the selection trials for the national squad, the results of which were used as a measure of bowling performance. For study II, the subjects were 21 members (12 males and 9 females) of the Singapore National Ten-Pin Bowling Squad that was formed after the selection trials. Interventions: none. MEASURES: Bowling grip strength, conventional grip strength, and bowling score. RESULTS: The test-retest reliability of the bowling grip strength measurement (r = 0.91, p < 0.01) was comparable to that of the conventional five-finger grip (r = 0.93, p < 0.01). The single measure intraclass correlation coefficient between the bowling and conventional grip strength tests was 0.77; the 95% confidence interval was 0.51 and 0.90. However, the correlation coefficient between the bowling grip strength test and bowling score (r = 0.27) was not significant. CONCLUSIONS: The bowling grip strength test has a high test-retest reliability, and a moderate agreement with the conventional grip strength test. However, despite using only the bowling fingers, the test was unable to predict bowling performance in elite bowlers.     

Correlations between upper limb oxygen kinetics and performance in elite swimmers

In swimming competitions, a good maximal oxygen uptake ( $ \dot V $ O_2max) is well correlated with performance in mid and long distance events. Along $ \dot V $ O_2max, oxygen uptake adaptation ( $ \dot V $ O kinetic) and oxygen consumption at steady state ( $ \dot V $ O_2ss) are also important factors that influence the performance. Concerning oxygen kinetic parameters, the primary time constant (τ) seems to play the main role in $ \dot V $ O kinetics. The purpose of this study was to look at a possible relationship between ?, as well as other physiologic parameters and performance in 400 m crawl in elite swimmers. Ten elite swimmers were tested in a swimming and in a laboratory in six sessions. $ \dot V $ O_2peak and ventilatory threshold (VT) were determined during an incremental to exhaustion test (ET) on an arm crank ergometer. A constant load tests (CT) at 75% (>VT) and 35% (<VT) of $ \dot V $ O_2max were performed for both arms (UBE) and legs (LBE) on the arm crank ergometer and a cycle ergometer respectively. A maximal 400m crawl (CR) was also swum and time trial was used as performance best. Peak power output (W_peak), heart rate (HR), lactate concentration [La^?], τ, as well as other physiologic parameters, were also identified. CR significantly correlated with W_peak (r= 0.81, p<0.01) and HR (r=0.71, p<0.05) in UBE. No significant correlations were found with τ (p>0.05). The results indicate that $ \dot V $ O kinetics, using our protocol, do not seem well correlated with CR in elite swimmers. Further studies are needed to clarify whether either using a swimming flume, or assessing long-distance and short-distance swimmers might give different results.     

Bowling workload and the risk of injury in elite cricket fast bowlers.

This study examined the relationship between the bowling workload of first-class cricket fast bowlers and injury with the aim of identifying a workload threshold at which point the risk of injury increases. Ninety male fast bowlers (mean age 27 years, range 18-38 years) from six Australian state squads were observed for the 2000-2001 and/or 2001-2002 cricket seasons. Workload was quantified by examining fixture scorecards and conducting surveillance at training sessions. Injury data was obtained from the Cricket Australia's Injury Surveillance System. Compared to bowlers with an average of 3-3.99 days between bowling sessions, bowlers with an average of less than 2 days (risk ratio (RR) = 2.4, 95% confidence interval (CI) 1.6 to 3.5) or 5 or more days between sessions (RR = 1.8, 95% CI 1.1 to 2.9) were at a significantly increased risk of injury. Compared to those bowlers with an average of 123-188 deliveries per week, bowlers with an average of fewer than 123 deliveries per week (RR = 1.4, 95% CI 1.0 to 2.0) or more than 188 deliveries per week (RR= 1.4, 95% CI 0.9 to 1.6) may also be at an increased risk of injury. There appears to be a dual fast bowling workload threshold beyond which the risk of injury increases and maintaining a workload that is too low or infrequent is an equally significant risk factor for injury as maintaining a high bowling workload. Further study is required to determine the reason why players who bowl infrequently suffer more injuries.     

Performance accuracy and functional variability in elite and developing fast bowlers

ObjectivesThe relationship between performance variability and accuracy in cricket fast bowlers of different skill levels under three different task conditions was investigated. Bowlers of different skill levels were examined to observe if they could adapt movement patterns to maintain performance accuracy on a bowling skills test.Design8 national, 12 emerging and 12 junior pace bowlers completed an adapted version of the Cricket Australia bowling skills test, in which they performed 30 trials involving short (n = 10), good (n = 10), and full (n = 10) length deliveries.MethodsBowling accuracy was recorded by digitising ball position relative to the centre of a target. Performance measures were mean radial error (accuracy), variable error (consistency), centroid error (bias), bowling score and ball speed. Radial error changes across the duration of the skills test were used to record accuracy adjustment in subsequent deliveries.ResultsElite fast bowlers performed better in speed, accuracy, and test scores than developing athletes. Bowlers who were less variable were also more accurate across all delivery lengths. National and emerging bowlers were able to adapt subsequent performance trials within the same bowling session for short length deliveries.ConclusionsAccuracy and adaptive variability were key components of elite performance in fast bowling which improved with skill level. In this study, only national elite bowlers showed requisite levels of adaptive variability to bowl a range of lengths to different pitch locations.     

The relationship between talent identification testing parameters and performance in elite junior swimmers

Objectives

In elite age-group swimming it is unclear to what degree common assessments of anthropometric, jump performance and front-crawl critical speed (CS) correlate with competition performance.

Correlations between physiological variables and performance in high level cross country off road cyclists

Objectives: To examine the relations between maximal and submaximal indices of aerobic fitness and off road cycling performance in a homogeneous group of high level mountain bikers. Methods: 12 internationally competitive mountain bikers completed the study. Maximum oxygen uptake (V^·O_2max), peak power output (PPO), power output (PO), and oxygen uptake (V^·O₂) at first (VT) and second (RCT) ventilatory thresholds were measured in the laboratory, and correlated with race time during a cross country circuit race. Results: The only physiological indices of aerobic fitness correlated with off road cycling performance were PO and V^·O₂ at RCT when normalised to body mass (r = –0.63 and r = –0.66, respectively; p<0.05). VT, V^·O_2max, and PPO were not correlated to performance in this homogeneous group of high level mountain bikers. Conclusions: The results of this study suggest that submaximal indices of aerobic fitness such as PO and V^·O₂ at RCT are more important determinants of off road cycling performance than maximal indices such as PPO and V^·O_2max. This study confirms the importance of body mass for mountain biking performance. As aerobic fitness explained only 40% of the variance, other physiological and technical factors should be investigated, as they may be important determinants of cross country performance among elite mountain bikers.     

Effects of heat stress on physiological responses and exercise performance in elite cyclists.

This study examined the effect of heat stress on physiological responses and exercise performance in elite road cyclists. Eleven members of the Australian National Road Cycling Squad completed two 30 min cycling time-trials in an environmental chamber set at either 32 degrees C, (HT) or 23 degrees C (NT) with a relative humidity of 60% in each circumstance. The trials were separated by two days, with six subjects performing HT first. Power output was 6.5% lower (P<0.05) during HT compared with NT. Mean skin temperature and sweat rate were higher (P<0.05) in HT compared with NT. In contrast, rectal temperature was remarkably similar throughout each trial. During the first 10 min of exercise in HT when power output was not different between trials, blood lactate was higher (P<0.05), and blood pH lower (P<0.05). In contrast, during the last 10 min of exercise when power output was reduced (P<0.05), blood lactate was lower (P<0.05), and pH higher (P<0.05), in HT. These data indicate that heat stress is associated with a reduced power output during self-paced exercise in highly trained men. This decrease in performance appears to be associated with factors associated with body temperature rather than metabolic capacity.     

Maximising performance in triathlon: applied physiological and nutritional aspects of elite and non-elite competitions.

Triathlon is a sport consisting of sequential swimming, cycling and running. The main diversity within the sport of triathlon resides in the varying event distances, which creates specific technical, physiological and nutritional considerations for athlete and practitioner alike. The purpose of this article is to review physiological as well as nutritional aspects of triathlon and to make recommendations on ways to enhance performance. Aside from progressive conditioning and training, areas that have shown potential to improve triathlon performance include drafting when possible during both the swim and cycle phase, wearing a wetsuit, and selecting a lower cadence (60-80 rpm) in the final stages of the cycle phase. Adoption of a more even racing pace during cycling may optimise cycling performance and induce a "metabolic reserve" necessary for elevated running performance in longer distance triathlon events. In contrast, drafting in swimming and cycling may result a better tactical approach to increase overall performance in elite Olympic distance triathlons. Daily energy intake should be modified to reflect daily training demands to assist triathletes in achieving body weight and body composition targets. Carbohydrate loading strategies and within exercise carbohydrate intake should reflect the specific requirements of the triathlon event contested. Development of an individualised fluid plan based on previous fluid balance observations may assist to avoid both dehydration and hyponatremia during prolonged triathlon racing.     

Radiological healing of lumbar spine stress fractures in elite cricket fast bowlers

ObjectivesReview magnetic resonance imaging (MRI) of elite adult fast bowlers with a history of lumbar spine stress fracture for evidence of bone healing. The findings will determine whether bone healing can occur in this population, and whether MRI may be used as a tool to assess bone healing and inform clinical decision making.DesignRetrospective cohort.MethodsParticipants were elite Australian fast bowlers who sustained a lumbar spine stress fracture confirmed on MRI and had at least one subsequent MRI. Two radiologists independently reviewed all images.ResultsThirty-one fractures from 20 male fast bowlers were reviewed. Median maximum fracture size was 6 mm (range 2–25 mm). Twenty-five fractures achieved bone healing, with a median 203 (IQR 141–301) days between the initial MRI (to confirm diagnosis) and the MRI when bone healing was observed. Fracture size and signal intensity of bone marrow oedema were positively associated with the number of days to the MRI when bone healing was observed (r² = 0.245, p < 0.001 and r² = 0.292, p < 0.001 respectively). Fractures which occurred at the same site as a previously united fracture took longer to heal than the first fracture (median 276 days to the MRI when bone healing was observed compared to 114 days for first fracture; p = 0.036).ConclusionsLumbar spine stress fractures in elite adult fast bowlers are capable of achieving complete bone healing, as demonstrated in the majority of bowlers in this study. Larger fractures, greater bone marrow oedema, and history of previous injury at the same site may require longer healing time which may be monitored with MRI.     

Heart rate and performance parameters in elite cyclists: a longitudinal study

PURPOSE: This study was designed to evaluate the stability of target heart rate (HR) values corresponding to performance markers such as lactate threshold (LT) and the first and second ventilatory thresholds (VT1, VT2) in a group of 13 professional road cyclists (VO2max, approximately 75.0 mL x kg(-1) x min(-1)) during the course of a complete sports season. METHODS: Each subject performed a progressive exercise test on a bicycle ergometer (ramp protocol with workload increases of 25 W x min(-1)) three times during the season corresponding to the "active" rest (fall: November), precompetition (winter: January), and competition periods (spring: May) to determine HR values at LT, VT1 and VT2. RESULTS: Despite a significant improvement in performance throughout the training season (i.e., increases in the power output eliciting LT, VT1, or VT2), target HR values were overall stable (HR at LT: 154 +/- 3, 152 +/- 3, and 154 +/- 2 beats x min(-1); HR at VT1: 155 +/- 3, 156 +/- 3, and 159 +/- 3 beats x min(-1); and at VT2: 178 +/- 2, 173 +/- 3, and 176 +/- 2 beats x min(-1) during rest, precompetition, and competition periods, respectively). CONCLUSION: A single laboratory testing session at the beginning of the season might be sufficient to adequately prescribe training loads based on HR data in elite endurance athletes such as professional cyclists. This would simplify the testing schedule generally used for this type of athlete.     

Relation between lower limb comfort and performance in elite footballers

ObjectivesSuccesses of the professional athlete as individuals and team, across codes of football are contingent upon performance measures. The aim of the study was to examine associations between comfort and performance.DesignProspective measures of lower limb comfort and coach rating performance criterion. Comfort and performance associations were described using Pearson’s correlation coefficient (r) or the R square value from the regression estimate.SettingTwo professional football codes in Australia.Participants79 professional footballers were followed for one football season, a total of 1724 player weeks.Main Outcome MeasuresStudy hypothesis was poor lower limb comfort is negatively correlated with good match day rated performance. Aspects of validity and responsiveness to change tested the hypothesis that lower limb comfort, affects rated performance. A validated lower limb comfort index (LLCI) was used to test comfort. Rated performance was evaluated by subjective rating criterion of experienced team coaches.ResultsPoor lower limb comfort and good match day ratings were not well correlated (R² = 0.25, P≤0.001) and usual-high comfort was correlated with usual-good performance (R² = 0.69, P≤0.001).ConclusionsLower limb comfort may be a sensitive measure of rated performance in football. The LLCI is the first measurement tool to show association between comfort and rated performance.     

Correlations between lactate and ventilatory thresholds and the maximal lactate steady state in elite cyclists

We investigated the validity of different lactate and ventilatory threshold methods, to estimate heart rate and power output corresponding with the maximal lactate steady-state (MLSS) in elite cyclists. Elite cyclists (n = 21; 21 +/- 0.4 y; VO2peak, 5.4 +/- 0.2 l x min (-1)) performed either one (n = 10) or two (n = 11) maximal graded exercise tests, as well as two to three 30-min constant-load tests to determine MLSS, on their personal race bicycle which was mounted on an ergometer. Initial workload for the graded tests was 100 Watt and was increased by either 5 % of body mass (in Watt) with every 30 s (T30 s), or 60 % of body mass (in Watt) with every 6 min (T6min). MLSS was defined as the highest constant workload during which lactate increased no more than 1 mmol x l (-1) from min 10 to 30. In T30 s and T6 min the 4 mmol (TH-La4), the Conconi (TH-Con) and dmax (TH-Dm) lactate threshold were determined. The dmax lactate threshold was defined as the point that yields the maximal distance from the lactate curve to the line formed by the lowest and highest lactate values of the curve. In T30 s also ventilatory (TH-Ve) and Vslope (TH-Vs) thresholds were calculated. Time to exhaustion was 36 +/- 1 min for T30 s versus 39 +/- 1 min for T6 min. None of the threshold measures in T30 s, except TH-Vs (r2 = 0.77 for heart rate) correlated with either MLSS heart rate or power output. During T6 min, power output at TH-Dm was closely correlated with MLSS power (r2=0.72). Low correlations were found between MLSS heart rate and heart rate measured at TH-Dm (r2=0.46) and TH-La4 (r2=0.25), respectively, during T6 min. It is concluded that it is not possible to precisely predict heart rate or power output corresponding with MLSS in elite cyclists, from a single graded exercise test causing exhaustion within 35-40 min. The validity of MLSS predicted from an incremental test must be verified by a 30-min constant-load test.     

Match-play performance comparisons between elite and sub-elite hurling players

Sport Sciences for Health - The current study aimed to describe the differences in the external and internal loads between elite and sub-elite male senior hurling match-play and across halves of...     

Correlations between VO2max and performance times of recreational triathletes.

Twenty-three recreational triathletes, 16 male and 7 female (mean = 21.7 yrs), performed max tethered swim (TS), cycle ergometer (CE), and treadmill run (TR) tests prior to participation in a competitive triathlon (0.91 km swim, 40 km cycle, 10 km run). The VO2max values on the TS, CE and TR were similar to those reported for trained athletes in each sport. As a group, cycling times were significantly correlated to both absolute (p less than 0.01) and relative (p less than 0.001) cycling VO2max (r = -0.57 and r = -0.78, respectively); running times significantly correlated with relative (p less than 0.001, r = -0.84) but not absolute (p greater than 0.05) running VO2max; and swimming times significantly correlated with absolute (p less than 0.01, r = -0.49) but not relative (p greater than 0.05) swimming VO2max. With the exception of absolute swim VO2max, the total performance times were significantly correlated to all VO2max values when expressed in both absolute and relative values. This study indicates the important role a moderately trained individual's aerobic power has in determining performances in endurance events such as the triathlon.     

Correlations between laboratory testing and distance running performance in marathoners of similar performance ability

Correlations between distance running performance and laboratory testing were examined in 11 marathoners of similar fitness (VO2max 66.4 +/- 1.7 ml/kg X min). They performed a graded treadmill test and a subsequent 30 km cross-country run. Heart rate, oxygen intake, blood lactate, and plasma catecholamines were measured during the treadmill test. Lactate equivalent, individual lactate threshold, 4 mmol lactate threshold, submaximum (16 km/h running velocity) lactate behavior, submaximum catecholamine responses, submaximum lactate-catecholamine product, measured VO2max, and extrapolated VO2max were examined for their adequacy in the evaluation of distance running capacity. Race times and free urine catecholamines were estimated in the field experiment. Direct correlations were found between race times and minimum lactate equivalent (r = 0.69), submaximum lactate levels (r = 0.52), submaximum catecholamine responses (r = 0.69), submaximum lactate-catecholamine product (r = 0.79), respectively. Inverse correlations were observed between race times and oxygen intake at individual lactate threshold (r = -0.68), 4 mmol lactate threshold (r = -0.76), measured VO2max (r = -0.71), and extrapolated VO2max (r = -0.63). Further correlations were found between submaximum noradrenaline and lactate behavior (r = 0.53), as well as between noradrenaline and adrenaline responses (r = 0.72). No significant correlation was observed between relative heart volumes or catecholamine excretion and race times.     

Seasonal deterioration of selected physiological variables in elite male skiers.

The purpose of this study was to determine whether seasonal deterioration in physiological variables could be observed in skiers. Eighteen international male British downhill, free-style, and speed skiers were subjected to a maximal treadmill running test, a 30-s Wingate test, and isokinetic dynamometry at the beginning, middle, and end of the 1989-90 competition season. Maximal oxygen intake (VO2max) and respiratory anaerobic threshold (T vent) were among the parameters measured on the treadmill test, while peak and mean power outputs were measured during the Wingate test. During dynamometry, knee flexors and extensors were bilaterally assessed at 1.04 and 3.14 rad.s-1. Mean VO2max (p < 0.01) and mean T vent (p < 0.05) were lower at the end compared to the beginning, but not compared to the middle of the competition season. The isokinetic test demonstrated lower mean peak torques at 1.04 rad.s-1, for the knee extensors measured at the end of the season, compared with both the start (p < 0.01) and the middle (p < 0.05). Also at 1.04 rad.s-1, knee flexors produced lower torques at the end than the start of the season (p < 0.05). No further statistical differences were found. It was concluded that seasonal deterioration in key physiological variables such as aerobic endurance and muscle strength, can be observed in elite alpine skiers, and that in-season fitness training programmes should take account of this.     

Somatotype, role and performance in elite volleyball players.

BACKGROUND: The purpose of the present study was to examine the importance of the somatometric components of elite male and female volleyball players in relation to their different game roles and levels of performance. METHODS: Two hundred and thirty-four male athletes (aged 24.7+/-4.4 years) and 244 female athletes (aged 23.1+/-4.4 years) from the Italian A1 and A2 volleyball leagues underwent anthropometric measurements during the 1992-1993 and 1993-1994 seasons. Somatotypes were estimated with the Heath-Carter method. RESULTS: Marked sexual dimorphism in somatotype was observed in the total sample. The average somatotype for men was 2.2-4.2-3.2 (SD 0.7-0.9-0.9), and for women it was 3.0-3.3-2.9 (SD 0.8-1.0-0.9). The somatotype was significantly different in players at different levels of performance (A1 vs A2 leagues), as it follows: 2.1-4.1-3.3 (SD 0.6-0.8-0.7) vs 2.3-4.3-3.0 (SD 0.7-1.0-0.8) in males; 2.9-3.1-3.0 (SD 0.8-1.0-0.9) vs 3.1-3.5-2.7 (SD 0.8-0.9-0.8) in females. The somatotype was also significantly different in players in different roles. In male sex the mean somatotypes for setters were 2.4-4.5-2.8 (SD 0.7-0.9-0.8), for centres they were 2.0-4.0-3.5 (SD 0.6-1.0-0.8), for spikers they were 2.2-4.3-3.0 (SD 0.6-0.9-0.7), for opposites they were 2.2-4.3-3.1 (SD 0.6-0.9-0.8). In female sex the mean somatotypes for setters were 3.1-3.6-2.5 (SD 0.8-1.0-1.0), for centres they were 2.8-3.1-3.1 (SD 0.8-0.9-0.7), for spikers they were 3.0-3.5-2.8 (SD 0.9-1.0-0.9) and for opposites they were 3.0-3.2-3.0 (SD 0.7-0.9-0.8). CONCLUSIONS: The physique of athletes in the A1 league is characterized by higher ectomorphy and lower endomorphy and mesomorphy. There is also a slight tendency of male players to a greater homogeneity in somatotype within the group at the maximum level of performance. Moreover somatotype differs in relation to game role in volleyball players of both sexes: the mesomorphic component is maximal in setters, while the ectomorphic component is maximal in centres.     

Evolution of physiological and haematological parameters with training load in elite male road cyclists: a longitudinal study

AIM: The aim of this study was to describe and evaluate physiological parameters as a control tool for the monitoring of training in a group of elite cyclists during one season of training. METHODS: The study is divided into two periods (winter or 'volume' mesocycle and spring or 'intensity' mesocycle) between the tests that they carried out in the laboratory, consisting of a ramp test to exhaustion (work load increases 25 W X min(-1)) and a maximal lactate steady state (MLSS) test on a cycle ergometer. Macronutrients and hematological variables were recorded during the test periods as were the volume and the intensity of training sessions during the whole period of the study. RESULTS: The physiological data were similar to those previously reported for professional cyclists (approximately 450 Watts, approximately 78 mL x kg(-1) x min(-1)) and the values for the MLSS also agree with previous studies (approximately 250 Watts). Subjects improved the first ventilatory threshold (VT(1)) (approximately 52% to approximately 60% VO(2max)) and the second ventilatory threshold (VT(2)) (approximately 82% to approximately 87% VO(2max)) after the first period of training even though its low intensity focused on the performance of VT(1) (77% training in 'zone 1', under VT(1)). The MLSS improved after the first period (approximately 225 to approximately 250 Watts) and remained high in the second (approximately 255 Watts). High levels of creatine kinase (approximately 230 U x L(-1)) and urea (37 mg x L(-1)) were found, also a decrease in hemoglobin values (approximately 15.4 to approximately 14.7g x dL(-1)). CONCLUSION: The high level reached by the subjects after the first period of training suggests that two effort tests could be enough to plan training. On the other hand, the decrease in some red blood cell and nutrition parameters suggests that there should be greater control over them during the season.