Background: Inertial measurement units (IMUs) are useful in monitoring running and alerting running-related injuries in various sports settings. However, the quantitative summaries of the validity and reliability of the measurements from IMUs during running are still lacking. The purpose of this review was to investigate the concurrent validity and test–retest reliability of IMUs for measuring gait spatiotemporal outcomes and lower extremity kinematics of health adults during running. Methods: PubMed, CINAHL, Embase, Scopus and Web of Science electronic databases were searched from inception until September 2021. The inclusion criteria were as follows: (1) evaluated the validity or reliability of measurements from IMUs, (2) measured specific kinematic outcomes, (3) compared measurements using IMUs with those obtained using reference systems, (4) collected data during running, (5) assessed human beings and (6) were published in English. Eligible articles were reviewed using a modified quality assessment. A meta-analysis was performed to assess the pooled correlation coefficients of validity and reliability. Results: Twenty-five articles were included in the systematic review, and data from 12 were pooled for meta-analysis. The methodological quality of studies ranged from low to moderate. Concurrent validity is excellent for stride length (intraclass correlation coefficient (ICC) (95% confidence interval (CI)) = 0.937 (0.859, 0.972), p < 0.001), step frequency (ICC (95% CI) = 0.926 (0.896, 0.948), r (95% CI) = 0.989 (0.957, 0.997), p  < 0.001) and ankle angle in the sagittal plane (r (95% CI) = 0.939 (0.544, 0.993), p = 0.002), moderate to excellent for stance time (ICC (95% CI) = 0.664 (0.354, 0.845), r (95% CI) = 0.811 (0.701, 0.881), p < 0.001) and good for running speed (ICC (95% CI) = 0.848 (0.523, 0.958), p = 0.0003). The summary Fisher's Z value of flight time was not statistically significant (p = 0.13). Similarly, the stance time showed excellent test–retest reliability (ICC (95% CI) = 0.954 (0.903, 0.978), p < 0.001) and step frequency showed good test–retest reliability (ICC (95% CI) = 0.896 (0.837, 0.933), p < 0.001). Conclusions: Findings in the current review support IMUs measurement of running gait spatiotemporal parameters, but IMUs measurement of running kinematics on lower extremity joints needs to be reported with caution in healthy adults. Trial Registration: PROSPERO Registration Number: CRD42021279395.

This systematic review aimed to analyse the effects of intrinsic foot muscle (IFM) training on foot function and dynamic postural balance. Keywords related to IFM training were used to search four databases (PubMed, CINAHL, SPORTDiscus and Web of Science databases.) for relevant studies published between January 2011 and February 2021. The methodological quality of the intervention studies was assessed independently by two reviewers by using the modified Downs and Black quality index. Publication bias was also assessed on the basis of funnel plots. This study was registered in PROSPERO (CRD42021232984). Sixteen studies met the inclusion criteria (10 with high quality and 6 with moderate quality). Numerous biomechanical variables were evaluated after IFM training intervention. These variables included IFM characteristics, medial longitudinal arch morphology and dynamic postural balance. This systematic review demonstrated that IFM training can exert positive biomechanical effects on the medial longitudinal arch, improve dynamic postural balance and act as an important training method for sports enthusiasts. Future studies should optimise standardised IFM training methods in accordance with the demands of different sports.

The study aimed to investigate the effects of 24 weeks Taichi intervention on knee and ankle proprioception amongst individuals with knee osteoarthritis (KOA). Ninety-two patients with KOA were included in the current study, involving 52 participants in the intervention group and 40 participants in the control group. The intervention group performed Taichi exercise for 24 weeks, the control group accepted the health education lectures. The main outcome of this study was the proprioception of the knee and ankle which was measured by an electric-driven movable frame. Between- and within-group differences were evaluated through the repeated-measurement ANOVA. For the Taichi group, the differences in the changes in ankle proprioception were significant on ankle plantarflexion (p = 0.03), ankle dorsiflexion (p = 0.043), ankle varus (p = 0.019) and knee flexion (p = 0.01) between the baseline and post-test measures. Twenty-four weeks Taichi exercise may improve the ankle and knee proprioception of patients with KOA.

Badminton players often perform powerful and long-distance lunges during such competitive matches. The objective of this study is to compare the plantar loads of three one-step maximum forward lunges in badminton. Fifteen right-handed male badminton players participated in the study. Each participant performed five successful maximum lunges at three directions. For each direction, the participant wore three different shoe brands. Plantar loading, including peak pressure, maximum force, and contact area, was measured by using an insole pressure measurement system. Two-way ANOVA with repeated measures was employed to determine the effects of the different lunge directions and different shoes, as well as the interaction of these two variables, on the measurements. The maximum force (MF) on the lateral midfoot was lower when performing left-forward lunges than when performing front-forward lunges (p = 0.006, 95% CI = −2.88 to −0.04%BW). The MF and peak pressures (PP) on the great toe region were lower for the front-forward lunge than for the right-forward lunge (MF, p = 0.047, 95% CI = −3.62 to −0.02%BW; PP, p = 0.048, 95% CI = −37.63 to −0.16 KPa) and left-forward lunge (MF, p = 0.015, 95% CI = −4.39 to −0.38%BW; PP, p = 0.008, 95% CI = −47.76 to −5.91 KPa). These findings indicate that compared with the front-forward lunge, left and right maximum forward lunges induce greater plantar loads on the great toe region of the dominant leg of badminton players. The differences in the plantar loads of the different lunge directions may be potential risks for injuries to the lower extremities of badminton players.

Background: Chronic ankle instability (CAI) is manifested by sensorimotor impairments in the sprained ankle, including deficits in sensation, motor function, and central integration or processing. These impairments have a significant impact on physical activities and daily life. Recently, some studies have suggested that bilateral deficits were observed in unilateral CAI, but contradictory evidence disputes this finding. Therefore, the objective of this study was to investigate whether bilateral sensorimotor deficits presented in individuals with unilateral CAI. Methods: Without language restriction, the following databases were retrieved from database inception up until 3 November 2023, including PubMed, WOS, EMBASE, Cochrane, SPORTDiscus and CINAHL. Case-control and cross-sectional studies that investigated bilateral sensorimotor functions in individuals with unilateral CAI were included. Sensorimotor functions contained static and dynamic balance, functional performance, muscle strength and activation, as well as sensation. Outcome measures contained centre-of-pressure parameters, normalised reach distance, activation time and magnitude of muscle, sensory errors and threshold. The risk of bias and quality assessment of included studies were evaluated using a standardised tool recommended by the Cochrane Collaboration and the Epidemiological Appraisal Instrument, respectively. To explore the potential bilateral deficits associated with unilateral CAI, a comprehensive meta-analysis was conducted using Review Manager version 5.4. The analysis compared the injured limb of unilateral CAI with healthy controls and the uninjured limb with healthy controls. The main focus of this study was to investigate the differences between the uninjured limb and healthy controls. A random-effects model was employed and effect sizes were estimated using the standardised mean difference (SMD) with 95% confidence intervals (CIs). Effect sizes were deemed as weak (0.2–0.5), moderate (0.5–0.8), or large (> 0.8). Results: A total of 11,442 studies were found; 30 studies were contained in the systematic review and 20 studies were included in the meta-analysis. Compared with healthy controls, those with unilateral CAI presented weak to moderate impairments in their uninjured limbs in static balance with eyes open (SMD = 0.32, 95% CI: 0.08 to 0.56), functional performance (SMD = 0.37; 95% CI: 0.08 to 0.67), kinesthesia (SMD = 0.52; 95% CI: 0.09 to 0.95) and tibialis anterior activation (SMD = 0.60, 95% CI: 0.19 to 1.01). There were no significant differences in other comparisons between the uninjured limb and healthy controls. Conclusions: Patients with unilateral CAI may present bilateral deficits in static balance with eyes open, functional performance and kinaesthesia. However, further evidence is required to confirm this point due to limited studies included in some analyses and small effect size. Registration: The protocol was registered in the International Prospective Register of Systematic Reviews platform (CRD: 42,022,375,855).

Background: Chronic ankle instability (CAI), which is characterized by deficient postural control, could be improved through kinesiology taping (KT). However, the effect of KT on postural control in CAI individuals is controversial. Therefore, this study aimed to investigate the acute effect of KT on postural control through computerized dynamic posturography (CDP) and self-perceived sensation in CAI individuals. Methods: Participants with CAI received four different ankle treatments randomly, including KT, athletic taping (AT), sham taping (ST), and no taping (NT). A series of postural stability measurements was performed using CDP subsequently. The measurements included sensory organization test (SOT), unilateral stance (US), limit of stability (LOS), motor control test (MCT), and adaption test (ADT). In addition, self-perceived sensation was measured through visual analog scaling. Repeated measures analysis of variance was conducted to determine whether the difference among KT, AT, ST, and NT was significant; Bonferroni test was used for post hoc analysis. Results: No significant difference was observed for parameters in SOT, US, and LOS in four different taping treatments. In MCT, the amplitude scaling scores of KT were 35.87% significantly lower than that of NT [p < 0.001, 95% confidence interval (CI) = 0.548–1.795] in forward-small slip and 21.58% significantly lower than that of ST (p = 0.035, 95% CI = 0.089–3.683) in backward-large slip. In ADT, sway energy scores were 7.59% significantly greater in ST than in AT (p = 0.028, 95% CI = −8.343 to −0.320). For perceived stability, KT was significantly greater than ST (p < 0.001, 95% CI = 0.552–1.899) and NT (p < 0.001, 95% CI = 0.797–2.534), and AT was significantly greater than ST (p = 0.001, 95% CI = 0.423–2.246) and NT (p < 0.001, 95% CI = 0.696–2.852). For perceived comfort, KT was significantly greater than AT (p = 0.001, 95% CI = 0.666–3.196) and NT (p = 0.031, 95% CI = 0.074–2.332), and ST was significantly greater than AT (p = 0.007, 95% CI = 0.349–2.931). Conclusion: KT and AT have limited effect to facilitate postural control for CAI individuals during SOT, US, and LOS. However, KT and AT could provide effective support to cope with sudden perturbation in MCT and ADT. Moreover, KT provided excellent perceived stability and comfort, whereas AT provided excellent perceived stability but least comfort.