title: Does load uncertainty affect adaptation to catch training?
abstract: Catching relies on anticipatory and compensatory control processes. Load uncertainty increases anticipatory and compensatory neuromotor effort in catching. This experiment tested the effect of load uncertainty in plyometric catch/throw training on elbow flexion reaction time (RT), movement time (MT) and peak torque, as well as the distribution of anticipatory and compensatory neuromotor effort in catching. We expected load uncertainty training to be superior to traditional training for improving elbow flexion MT and peak torque, as well as for reallocating neuromotor effort from compensatory to anticipatory control in catching. Three groups of men (mean age = 21), load knowledge training (K) (n = 14), load uncertainty training (U) (n = 13) and control (C) (n = 14), participated. Groups K and U trained three times/week for 6 weeks using single-arm catch/throw exercises with 0.45-4.08 kg balls. Sets involved 16 repetitions of four different ball masses presented randomly. Group K had knowledge of ball mass on every repetition, whereas group U never did. Change scores were analyzed using Kruskal-Wallis tests and follow-up Wilcoxon rank-sum tests. Group K improved both RT and MT (by 6.2 and 12 %, respectively), whereas group U did not. Both groups K and U improved peak eccentric elbow flexion torque. Group K reallocated neuromotor effort from compensatory to anticipatory processes in the biceps, triceps and the all muscle average, whereas group U did so in the triceps only. In sum, plyometric catch/throw training caused a reallocation of neuromotor effort from compensatory to anticipatory control in catching. However, load uncertainty training did not amplify this effect and in fact appeared to inhibit the reallocation of neuromotor effort from compensatory to anticipatory control.
authors.affiliation: Department of Kinesiology and Health, Miami University, 202G Phillips Hall, Oxford, OH, 45056, USA. bergwp@miamioh.edu.
authors.forename: William P
authors.initials: WP
authors.lastname: Berg
authors.affiliation: School of Health Sciences, Cleveland State University, 2121 Euclid Avenue, HS 101, Cleveland, OH, 44115, USA.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Richards
authors.affiliation: School of Health and Rehabilitation Sciences, The Ohio State University, 453 West 10th Avenue, Columbus, OH, 43210, USA.
authors.forename: Aaron M
authors.initials: AM
authors.lastname: Hannigan
authors.affiliation: Division of Physical Therapy, Ohio University, 290 Grover Center, Athens, OH, 45701, USA.
authors.forename: Kelsey L
authors.initials: KL
authors.lastname: Biller
authors.affiliation: Department of Statistics, Miami University, 308 Upham Hall, Oxford, OH, 45056, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Hughes
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D004576:Electromyography / Q000379:methods; D006801:Humans; D008297:Male; D009068:Movement; D018482:Muscle, Skeletal / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D011930:Reaction Time; D035501:Uncertainty
keywords: Anticipatory control; Catching; Compensatory control; Load knowledge; Load uncertainty; Plyometric training