Acute and Longitudinal Effects of Sport-related Concussion on Reactive Balance.

Postural instability is a common observation after concussions, with balance assessments playing a crucial role in clinical evaluations. Widely used post-concussion balance tests focus primarily on static and dynamic balance, excluding the critical aspect of reactive balance. This study investigated the acute and longitudinal effects of concussion on reactive balance in collegiate athletes. The assessments were conducted at pre-season baseline and 4 post-concussion timepoints: acute, pre-return-to-play, post-return-to-play, and six months post-concussion. The instrumented-modified Push and Release test measured reactive balance. Longitudinal effects of concussions on time to stability and step latency metrics were investigated applying Generalized Estimating Equations. Acutely after concussion, athletes demonstrated impaired reactive balance, indicated by longer times to stability, in dual-task conditions ( p = 0.004). These acute impairments were transient and recovered over time. Exploratory analyses revealed that athletes who sustained their first lifetime concussion exhibited both acute ( p = 0.037) and longitudinal ( p = 0.004 at post-return-to-play) impairments in single- and dual-task compared to controls with no lifetime concussion. This comprehensive evaluation provides insights into the multifaceted nature of post-concussion impairments and emphasizes the importance of considering cognitive demand and history of concussions in assessing athletes' balance.

Improving the reliability of underwater gait analysis using wearable pressure and inertial sensors.

This work addresses the lack of reliable wearable methods to assess walking gaits in underwater environments by evaluating the lateral hydrodynamic pressure exerted on lower limbs. Sixteen healthy adults were outfitted with waterproof wearable inertial and pressure sensors. Gait analysis was conducted on land in a motion analysis laboratory using an optoelectronic system as reference, and subsequently underwater in a rehabilitation swimming pool. Differences between the normalized land and underwater gaits were evaluated using temporal gait parameters, knee joint angles and the total water pressure on the lower limbs. The proposed method was validated against the optoelectronic system on land; gait events were identified with low bias (0.01s) using Bland-Altman plots for the stride time, and an acceptable error was observed when estimating the knee angle (10.96° RMSE, Bland-Altman bias -2.94°). The kinematic differences between the land and underwater environments were quantified, where it was observed that the temporal parameters increased by more than a factor of two underwater (p<0.001). The subdivision of swing and stance phases remained consistent between land and water trials. A higher variability of the knee angle was observed in water (CV = 60.75%) as compared to land (CV = 31.02%). The intra-subject variability of the hydrodynamic pressure on the foot ([Formula: see text] = 39.65%) was found to be substantially lower than that of the knee angle (CVz = 67.69%). The major finding of this work is that the hydrodynamic pressure on the lower limbs may offer a new and more reliable parameter for underwater motion analysis as it provided a reduced intra-subject variability as compared to conventional gait parameters applied in land-based studies.

Forward and Backward Walking: Multifactorial Characterization of Gait Parameters.

Although extensive literature exists on forward and backward walking, a comprehensive assessment of gait parameters on a wide and homogenous population is missing. Thus, the purpose of this study is to analyse the differences between the two gait typologies on a relatively large sample. Twenty-four healthy young adults participated in this study. By means of a marker-based optoelectronic system and force platforms, differences between forward and backward walking were outlined in terms of kinematics and kinetics. Statistically, significant differences were observed in most of the spatial-temporal parameters, evidencing some adaptation mechanisms in backward walking. Differently from the ankle joint, the hip and knee range of motion was significantly reduced when switching from forward to backward walking. In terms of kinetics, hip and ankle moment patterns for forward and backward walking were approximately mirrored images of each other. Moreover, joint powers appeared drastically reduced during reversed gait. Specifically, valuable differences in terms of produced and absorbed joint powers between forward and backward walking were pointed out. The outcomes of this study could represent a useful reference data for future investigation evaluating the efficacy of backward walking as a rehabilitation tool for pathological subjects.

Wearable technologies for monitoring aquatic exercises: A systematic review.

OBJECTIVE: To review methods for aquatic exercise monitoring using wearables. DATA SOURCES: Database search of PubMed, IEEEXplore, Scopus and Web of Science based on keywords, considering articles from the year 2000. The last search was performed on 26 October 2022. REVIEW METHODS: Following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) protocol, eligible articles on water exercises were selected and summarized. Further screening process concentrated on studies exploiting wearable devices, organized according to demographics, purpose, protocols, outcomes and methods. A custom critical appraisal questionnaire was applied. RESULTS: Out of the 1062 articles identified, 572 were considered eligible and subjected to preliminary synthesis. The final review focused on 27 articles featuring wearable devices applied to aquatic exercises. Four studies were disregarded as they applied wearable devices to determine daily physical activity or for sleep monitoring after training. Summary tables of 23 studies exploiting wearable devices for underwater motion analysis are provided, specifying the investigated parameters, major outcomes and study quality. This review identified four research gaps: (a) the absence of clinical protocols for underwater motion studies, (b) a deficit of whole-body studies, (c) the lack of longitudinal studies monitored via wearable devices and (d) the reliance of underwater studies on measurement and assessment methods developed for land-based investigations. CONCLUSIONS: This review emphasizes the need for both technological and methodological improvements for underwater motion analysis studies using wearables. We advocate for longitudinal clinical investigations with wearables to substantiate water exercise as an addition or replacement for land-based physical activity.