Determining Quality Movement Through Acceleration And Self-perception

A dynamic systems perspective suggests that a complex system (individual) self-organizes into unique and identifiable patterns. Describing an individual’s resulting movement pattern in terms of quality may best be accomplished through considering multiple inputs. Drawing connections between self-perception and direct measures may provide insights of movement quality. PURPOSE: To demonstrate a connection between movement performance and perception of movement skill during a squat motion. METHODS: Subjects (N = 22) were fitted with a 3-D accelerometer (AC) at sternum and asked to perform 20 squats after completing a questionnaire using a Lower Extremity (LE) Functional Scale to measure perception of LE function. AC values were recorded for each axis and analyzed using Python to determine repetition time (RPT) in s, amplitude (AMP) in g, and questionnaire responses (QR). Spearman rank ordering was computed to compare values between different measurements. Quality of movement was considered through three domains. Averages and standard deviations were computed for each axis of motion to find consistency. Coordination of movement was found by comparing values of RPT, AMP and QR. Optimality of movement was found by comparing the correlation of motion between augmented axes. RESULTS: Perception: QR = 69.5 (+ 20.1); Consistency: X-AMP = 0.14 g (+ 0.06); Y-AMP = 0.58 g (+ 0.34), Z-AMP = 0.82 g (+ 0.34); RPT = 1.61 s (+ 0.36); Coordination: Z-AMP to QR: r = .525 (p < 0.05); Optimality: Y/X-AMP to Z/X-AMP: r = 0.75 (p < 0.05); RPT-STD to QR r = 0.59 (p < 0.05). CONCLUSIONS: Subjects performed squats with minimal left-right motion and greater motion in front-back. A greater perception of movement ability occurred with squatters who had more front-back motion. Augmented views suggest there is a relationship between vertical and front to back motion with a minimal left to right motion. Most interesting is that a more consistent RPT may be related to a greater perception of movement. Findings suggest that movement quality of a squat may be demonstrated through acceleration values. Ideally, such insights may be used to better interpret various movements, advance assessment, programming and monitoring.