A Proposed Framework to Describe Movement Variability within Sporting Tasks: A Scoping Review

Abstract

Movement variability is defined as the normal variations in motor performance across multiple repetitions of a task. However, the term “movement variability” can mean different things depending on context, and when used by itself does not capture the specifics of what has been investigated. Within sport, complex movements are performed repeatedly under a variety of different constraints (e.g. different situations, presence of defenders, time pressure). Movement variability has implications for sport performance and injury risk management. Given the importance of movement variability, it is important to understand the terms used to measure and describe it. This broad term of “movement variability” does not specify the different types of movement variability that are currently being assessed in the sporting literature. We conducted a scoping review (1) to assess the current terms and definitions used to describe movement variability within sporting tasks and (2) to utilise the results of the review for a proposed framework that distinguishes and defines the different types of movement variability within sporting tasks. To be considered eligible, sources must have assessed a sporting movement or skill and had at least one quantifiable measure of movement variability. A total of 43 peer-reviewed journal article sources were included in the scoping review. A total of 280 terms relating to movement variability terminology were extracted using a data-charting form jointly developed by two reviewers. One source out of 43 (2%) supplied definitions for all types of movement variability discussed. Moreover, 169 of 280 terms (60%) were undefined in the source material. Our proposed theoretical framework explains three types of movement variability: strategic, execution, and outcome. Strategic variability describes the different approaches or methods of movement used to complete a task. Execution variability describes the intentional and unintentional adjustments of the body between repetitions within the same strategy. Outcome variability describes the differences in the result or product of a movement. These types emerged from broader frameworks in motor control and were adapted to fit the movement variability needs in sports literature. By providing specific terms with explicit definitions, our proposed framework can ensure like-to-like comparisons of previous terms used in the literature. The practical goal of this framework is to aid athletes, coaches, and support staff to gain a better understanding of how the different types of movement variability within sporting tasks contribute to performance. The framework may allow training methods to be tailored to optimise the specific aspects of movement variability that contribute to success. This review was retrospectively registered using the Open Science Framework (OSF) Registries (https://osf.io/q73fd).

The influence of proximal motor strategies on pianists' upper-limb movement variability

“…Movement variability is a common measure of coordination in biomechanics research, especially in sports (Bartlett et al, 2007) and ergonomics (Preatoni et al, 2013). There are two main types of movement variability: 1) intra-participant movement variability, which is the difference between a single individual's movements when performing repetitions of the same task (Cowin et al, 2022;Zhao et al, 2021), and 2) inter-participant movement variability, which is the difference between multiple individuals' movements while performing the same task (Zhao et al, 2021). Biomechanics research can use movement variability to understand musculoskeletal pathomechanisms (Preatoni et al, 2013).…”

How functional movement variability facilitates successful skill adaptation during the volleyball attack

“…13 Ecological dynamics proposed the notion of representative task design, that is, advocating how coaches need to carefully manipulate task constraints to make affordances (opportunities for action) 14 available that learners can explore, finding their own functional performance solutions. 15 Pedagogical principles of the constraints-led approach (CLA) seek to provide learning and training opportunities that: (i) encourage self-organisation of behaviour under constraints, 16 (ii) induce movement pattern variability (strategic and execution variability) in representative task designs, [17][18][19][20] (iii) promote the coupling of information and movement as skill develops, (iv) support adaptive skill performance and (v) empower athletes to explore functional performance solutions during practice. 21,22 Because ecological dynamics proposes that actions are continuously re-organised and regulated by information from the environment, context is everything in practice designs.…”

“…Pedagogical principles of the constraints-led approach (CLA) seek to provide learning and training opportunities that: (i) encourage self-organisation of behaviour under constraints, 16 (ii) induce movement pattern variability (strategic and execution variability) in representative task designs, 17–20 (iii) promote the coupling of information and movement as skill develops, (iv) support adaptive skill performance and (v) empower athletes to explore functional performance solutions during practice. 21,22…”

Is movement variability altered in people with chronic non-specific low back pain? A systematic review

“…Increased variability could also be considered as a beneficial component for motor performance, as it may reduce the risk of injury by distributing joint loads [ 15 ]. However, it is not well established how trunk movements should ideally be performed in terms of the adequate amount of motor variability, stability and complexity to achieve a coordinated movement that doesn’t predispose an individual to injury, specifically during dynamic and repetitive tasks [ 16 ].…”