The one-week and six-month reliability and variability of three-dimensional tibial acceleration in runners

Abstract

Tibial acceleration is a surrogate measure for impact loading and lower limb fatigue injury in runners. Triaxial accelerometers may offer reliable and practical measurement of resultant peak tibial acceleration (PTA). With such potential in mind, this study examined variability and measurement reliability of tibial acceleration in 14 runners at baseline at one week, and eight of the runners again at six months. Triaxial accelerometers were attached to the distal tibiae of runners before they ran on a treadmill for two minutes each, at speeds of 2.7, 3.0, 3.3 and 3.7 m/s in standardised shoes. Resultant PTAs were calculated for each speed and session. Reliability outcomes were presented as percentage change and effect sizes. Variability outcomes included intraclass correlation coefficients and the typical error of the measurement. Smallest worthwhile change and performance/noise ratio were also calculated. While runners demonstrated marginally lower reliability and higher variability over six months, compared to one week, in all cases the measures of reliability and variability were of 'good' to 'moderate' reliability, and 'small' to 'moderate' variability using magnitude-based inferences. We can be confident that resultant PTA can be used with runners to assess and monitor their impacts throughout a six-month intervention.

Validity and reliability of peak tibial accelerations as real-time measure of impact loading during over-ground rearfoot running at different speeds

“…As expected, different PTAs were registered when running speed was altered. The increments in axial and resultant PTAs at the lower speeds in this over-ground setting were rather analogous to those on treadmill (Sheerin et al, 2016). When speeding from 3.2 to 5.1 m*s -1 the relative increase in resultant PTA stems with that of axial PTA (± 80%).…”

“…No statistically significant difference in PTAs was found between-sessions, although the repeatability of resultant PTA was superior to axial PTA. During treadmill running, Sheerin and Besier (2016) also found better repeatability for resultant PTA up to the tested speed of 3.7 m*s -1 . Despite the poor-tomoderate reliability for axial PTA between-sessions, the minimum detectable difference in axial PTA at the speed resembling training pace (1.4 g) was smaller than the change in axial PTA (3.3 g) after completing a biofeedback-oriented running retraining program (Clansey et al, 2014) meaning that the changes induced by biofeedback on axial PTA outweigh measurement variability.…”

“…There namely occurs a sudden change in velocity of the lower leg segment in both vertical and horizontal directions (Lafortune, 1991), and both may contribute to the overall severity of lower leg impact. Resultant PTA seems reliable during treadmill running (Sheerin et al, 2017), although its reliability has to be tested when running over-ground at different speeds.…”

3D propagation of the shock-induced vibrations through the whole lower-limb during running

“…the ones occurring in the plane orthogonal to the longitudinal component). Consequently, Sheerin et al (2018) chose to approach studying the vibration magnitude, instead of the three independent axes., Likewise, Giandolini et al (2016) addressed the transverse shock acceleration relative to the axial component. According to Lafortune et al (1991), Giandolini et al (2016) indicated that the vibration magnitude along the transverse plane (approximately 9 g) was similar to the vibration magnitude of the axial acceleration (approximately 10 g) while running downhill.…”

The value of tibial mounted inertial measurement units to quantify running kinetics in elite football (soccer) players. A reliability and agreement study using a research orientated and a clinically orientated system

“…In the absence of a gold standard it is important to investigate the agreement between similarly established systems (Bland and Altman, 1986). Although there have been no studies that have investigated agreement between IMU systems, a research orientated IMU system has previously been shown to have good between-session reliability for tibial acceleration measurements at various running speeds when measured at 1 week and 6 months (Sheerin et al, 2018). However, as male recreational runners were investigated, it is unlikely that these results are generalisable to elite football players.…”