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Effects of prolonged running on Achilles tendon properties were assessed after a 60 min treadmill run and 140 min intermittent shuttle running (simulated cricket batting innings). Before and after exercise, 11 participants performed ramp-up plantar flexions to maximum-voluntary-contraction before gradual relaxation. Muscle-tendon-junction displacement was measured with ultrasonography. Tendon force was estimated using dynamometry and a musculoskeletal model. Gradients of the ramp-up force-displacement curves fitted between 0−40% and 50−90% of the preexercise maximal force determined stiffness in the low- and high-force-range, respectively. Hysteresis was determined using the ramp-up and relaxation force-displacement curves and elastic energy storage from the area under the ramp-up curve. In simulated batting, correlations between tendon properties and shuttle times were also assessed. After both protocols, Achilles tendon force decreased (4% to 5%, P < .050), but there were no changes in stiffness, hysteresis, or elastic energy. In simulated batting, Achilles tendon force and stiffness were both correlated to mean turn and mean sprint times (r = −0.719 to −0.830, P < .050). Neither protocol resulted in fatigue-related changes in tendon properties, but higher tendon stiffness and plantar flexion force were related to faster turn and sprint times, possibly by improving force transmission and control of movement when decelerating and accelerating. [ABSTRACT FROM AUTHOR]

The increased focus on power hitting in Twenty 20 cricket makes it relevant for cricket strength and conditioning coaches to consider novel methods to increase cricket bat velocity. Therefore, the aim of this pilot study was to investigate whether a novel, weighted ball training program would increase cricket bat velocity. Eight academy cricket players (18.3 ± 0.5 years, 178.4 ± 5.1 cm, 76.5 ± 8.9 kg) completed a 2-week (9 sessions) training program. At the end of each skill session participants hit the weighted balls by playing a front foot drive to a drop feed (total repetitions per session increasing from 12 to 32). Throughout the training, four players used balls weighing 290 g and four players used balls weighing 233 g (standard cricket ball 168 g). Before and after the training program, maximum bat and ball velocity were determined (3D motion analysis system) for the front foot drive when hitting a stationary cricket ball as hard as possible. Due to the small sample size, both the 233 g and 290 g weighted ball groups were combined together in the final analysis. Ball velocity increased 4.1% (24.09 ± 1.42 to 25.08 ± 2.17 km.h-1) but the effect size was small (0.5) and the difference was less than the typical error (4.2%). Bat velocity increased 5.8% (13.95 ± 1.08 to 14.76 ± 1.47 km.h-1) with a moderate effect size (0.6) but the difference was less than the typical error (9.6%). In conclusion, cricket bat and ball velocities were similar pre-and post a 2-week, weighted ball training program. [ABSTRACT FROM AUTHOR]

The article discusses a study of the benefits of plyometric training methods in cricket players, focusing on changes in performance in intermittent shuttle running in simulated cricket innings and the mechanical properties of the Achilles tendon. Subjects were evaluated for sprint times and countermovement and squat jumping before and after an 8 week plyometric training regimen, as well as monitoring of the strength and elasticity of the Achilles tendon using dynamometry and ultrasonography.

The time-course of physical recovery was determined after a 2-h 20-min, simulated cricket batting innings. Several vertical jump measures were assessed before (baseline), immediately after, 24 h after and 48 h after simulated batting. Six, male, academy cricketers (20 ± 2 years) completed a previously developed simulated batting innings (BATEX) at an outdoor net facility. At each assessment point, participants completed countermovement-jumps, squat-jumps and 5-repeated reactive-jumps on a contact mat. Compared with baseline, countermovement flight time was similar immediately after, but decreased 24 h after batting (−3.0 ± 1.8%, p < 0.05, effect size [ES] ± 90% confidence interval [CI]: −1.38 ± 0.52). At 48 h post, countermovement-jump flight time was similar to baseline. A similar pattern occurred in the squat-jump and the decrease in squat-jump flight time 24 h after simulated batting approached significance (p = 0.053, ES ± CI −0.80 ± 0.51). The 5-repeated reactive-jump measures (flight time, contact time and reactive-strength-index) did not decrease after simulated batting (p > 0.05), but there were moderate effect sizes calculated (0.64–0.96). These findings support the continued use of countermovement flight time to assess recovery in cricket, since full recovery of jump performance occurred 48 h after a simulated, prolonged and high intensity-batting century. [ABSTRACT FROM AUTHOR]

The reliability (test–retest) of running-between-the-wickets times and skill performance was assessed during a batting exercise (BATEX) simulation of 2 h 20 min duration that requires intermittent shuttle running. In addition, performance and physiological responses (heart rate, sweat rate, rating of perceived exertion, blood lactate concentration) were compared between high- and low-grade district club batsmen (n = 22, mean ± s: age 20 ± 2 years, mass 73.4 ± 8.5 kg). Running-between-the-wickets performance was assessed with an infra-red timing system (Swift, Australia) by sampling a 5-m time for the middle section of the straight-line sprints (singles) and the time to complete 5 m in and out of the turn (5-0-5-m turn time). Skill performance was rated as a percentage for good bat–ball contacts. Coefficients of variation for running-between-the-wickets performance and percentage of good bat–ball contacts were both <5%. Percentage of good bat–ball contacts was greater in the high- than low-grade batsmen (70 ± 8 vs. 58 ± 9%, P = 0.01). All other variables were similar between grades. Running-between-the-wickets and skill-performance measures during the BATEX simulation were reliable, thus it can be used in future research. [ABSTRACT FROM PUBLISHER]

A simulated cricket batting innings was developed to replicate the physical demands of scoring a century during One-Day International cricket. The simulated innings requires running-between-the-wickets across six 5-over stages, each of 21 min duration. To validate whether the simulated batting innings is reflective of One-Day International batting, movement patterns were collected using a global positioning system (GPS) and compared with previous research. In addition, indicators of physical strain were recorded (heart rate, jump heights, sweat loss, tympanic temperature). Nine club cricketers (mean ± s: age 20 ± 3 years; body mass 79.5 ± 7.9 kg) performed the simulated innings outdoors. There was a moderate trend for distance covered in the simulated innings to be less than that during One-Day batting (2171 ± 157 vs. 2476 ± 631 m · h-1; effect size = 0.78). This difference was largely explained by a strong trend for less distance covered walking in the simulated innings than in One-Day batting (1359 ± 157 vs. 1604 ± 438 m · h-1; effect size = 1.61). However, there was a marked trend for distance covered both striding and sprinting to be greater in the simulated innings than in One-Day batting (effect size > 1.2). Practically, the simulated batting innings may be used for match-realistic physical training and as a research protocol to assess the demands of prolonged, high-intensity cricket batting. [ABSTRACT FROM AUTHOR]

This study followed a repeated-measures design (n = 12, age range 18-22 years) and measured times to run a single: holding the bat in one hand (1H), or 'paddling' with the bat in two hands (2H); and times to turn when running a two and three run: holding the bat in the stronger hand and turning on the perceived strong side (1H+S); holding the bat in two hands and turning on the perceived strong side (2H+S); or holding the bat in two hands and turning on the perceived weak side (2H+W). For the singles, time was measured between 0 and 17.7 m. For the two and three runs, turn time was measured for the 5 m deceleration into and 5 m acceleration out of the 180° turn. Values are mean ± typical error. It was significantly quicker to run a single using the 1H compared to the 2H technique (1H vs. 2H: 3.110 ± 0.099 s vs. 3.165 ± 0.080 s, p = 0.032). There was a significant trial effect for turning in a two (1H+S vs. 2H+S vs. 2H+W: 2.318 ± 0.114 s vs. 2.363 ± 0.098 vs. 2.399 ± 0.097 s; p = 0.027). Similarly, 1H+S was the quickest turn technique when running a three (p = 0.018). The fastest running between the wicket technique is to hold the bat in one hand and turn on the perceived strongest side. [ABSTRACT FROM AUTHOR]

Summary: Anecdotal evidence suggests compression garments (CGs) are being worn underneath normal playing attire during team sports. Wearing CGs as a baselayer could possibly increase heat storage, and so this field study investigated the effects of wearing CGs, comprising knee-length shorts and short-sleeved top underneath normal match-day attire (COMP), versus normal match-day attire alone (NORM) on thermoregulation during simulated team sport activity. Ten match-fit field hockey players twice performed 4×15min exercise bouts consisting of repeated cycles of intermittent, varied-intensity 20m shuttle running (Loughborough intermittent shuttle test), once in COMP and once in NORM. Testing was conducted in an indoor gymnasium (ambient conditions: ∼17°C, ∼60% relative humidity). Participants acted as their own controls. Heart rate (HR), 15m sprint time, ratings of perceived exertion (RPE), blood lactate concentration, sweat rate and body core temperature (T core) were similar between trials (p >0.05). Mean skin temperature (T skin) was significantly higher in COMP than NORM (p <0.05). Overall, CGs worn as a baselayer during simulated team sport exercise in temperate ambient conditions had no thermoregulatory benefits nor any detrimental effects on T core, physiological performance or dehydration. However, the higher T skin may affect individual preference for wearing CGs as an undergarment during team sports. [Copyright &y& Elsevier]

Following fixed-duration exercise of submaximal intensity, caffeine ingestion is associated with an attenuation of the exercise-induced decline in N-formyl-methionyl-phenyl-alanine (f-MLP) stimulated neutrophil oxidative burst. However, the response following high-intensity exhaustive exercise is unknown. Nine endurance-trained male cyclists ingested 6 mg caffeine or placebo per kilogram of body mass 60 min before cycling for 90 min at 70% of maximal oxygen consumption ([Vdot]O2max) and then performing a time-trial requiring an energy expenditure equivalent to 30 min cycling at 70% maximum power output. Time-trial performance was 4% faster in the caffeine than in the placebo trial (P = 0.043). Caffeine was associated with an increased plasma adrenaline concentration after 90 min of exercise (P = 0.046) and immediately after the time-trial (P = 0.02). Caffeine was also associated with an increased serum caffeine concentration (P < 0.01) after 90 min of exercise and immediately after the time-trial, as well as 1 h after the time-trial. However, the f-MLP-stimulated neutrophil oxidative burst response fell after exercise in both trials (P = 0.002). There was no effect of caffeine on circulating leukocyte or neutrophil counts, but the lymphocyte count was significantly lower on caffeine (20%) after the time-trial (P = 0.003). Our results suggest that high-intensity exhaustive exercise negates the attenuation of the exercise-induced decrease in neutrophil oxidative burst responses previously observed when caffeine is ingested before exercise of fixed duration and intensity. This may be associated with the greater increase in adrenaline concentration observed in the present study. [ABSTRACT FROM AUTHOR]