title: Number of Directional Changes Alters the Physiological, Perceptual, and Neuromuscular Responses of Netball Players During Intermittent Shuttle Running.
abstract: This study investigated whether an increased number of changes in direction altered the metabolic, cardiovascular, perceptual, and neuromuscular responses to intermittent shuttle running (ISR). Using a randomized crossover design, 10 female netball players completed 30 minutes of ISR over a 10-m (ISR10) and 20-m (ISR20) linear course. Measures of expired air, heart rate (HR), rating of perceived exertion, blood lactate concentration ([BLa]), and peak torque of knee extensors and flexors were measured. Differences (%change ± 90% CL) in VO2 (1.5 ± 5.6%) was unclear between conditions, whereas HR was possibly higher (1.5 ± 2.5%) and [BLa] very likely lower in ISR20 compared with ISR10 (-32.7 ± 9.9%). Rating of perceived exertion was likely lower in the ISR20 compared with the ISR10 condition at 15 (-5.0 ± 5.0%) and most likely lower at 30 minutes (-9.4 ± 2.0%). Sprint times over 20 m were likely slower during ISR20 at mid (3.9 ± 3.2%) but unclear after (2.1 ± 5.4%). Changes in muscle function were not different between ISR10 and ISR20 conditions for knee extension (-0.2 ± 0.9%) but were likely different for knee flexion (-5.7 ± 4.9%). More directional changes during shuttle running increase the physiological and perceptual load on female athletes, which also cause a greater reduction in knee extensor torque. These findings have implications for the effective conditioning and injury prevention of female team sport athletes.
authors.affiliation: Department of Sport and Exercise Sciences, University of Chester, Chester, United Kingdom.
authors.forename: Ruth E M
authors.initials: RE
authors.lastname: Ashton
authors.forename: Craig
authors.initials: C
authors.lastname: Twist
mesh_terms: D000328:Adult; D056352:Athletes; D054874:Athletic Performance / Q000502:physiology; D018592:Cross-Over Studies; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D019344:Lactic Acid / Q000097:blood; D005082:Physical Exertion / Q000502:physiology; D011897:Random Allocation; D012420:Running / Q000502:physiology*; D019415:Torque; D055815:Young Adult
chemical_list: D019344:Lactic Acid