Walking a thin line between fixation and epitope binding - characterization of antigen retrieval methods suitable for eosinophil and HSV-2 staining in formalin-fixed female reproductive tissue.

Antibody-based fluorescence analysis of female reproductive tissues in research of sexually transmitted diseases allows for an in-depth understanding of protein localization, interactions, and pathogenesis. However, in many cases, cryosectioning is not compatible with biosafety regulations; at all times, exposure of lab personnel and the public to potentially harmful pathogens from biological infectious material must be avoided; thus, formaldehyde fixation is essential. Due to formaldehyde's cross-linking properties, protein detection with antibodies can be impeded. To allow effective epitope binding during immunofluorescence of formalin-fixed paraffin-embedded vaginal tissue, we investigated two antigen retrieval methods. We tested these methods regarding their suitability for automated image analysis, facilitating reproducible quantitative microscopic data acquisition in sexually transmitted disease research. Heat-based retrieval at 80°C in citrate buffer proved to increase antibody binding to eosinophil protein and HSV-2 visibly and tissue morphology best, and was the most efficient for sample processing and quantitative analysis.

Minimal clinically important differences in six-minute walking distance in late-onset Pompe disease.

BACKGROUND: The minimal clinically important difference (MCID) is the smallest change in outcome that physicians or patients would consider meaningful and is relevant when evaluating disease progression or the efficacy of interventions. Studies of patients with late-onset Pompe disease (LOPD) have used the 6-min walk distance (6MWD) as an endpoint to assess motor function. However, an MCID for 6MWD (% predicted and meters) has yet to be established in LOPD. The objective of the study was to derive 6MWD MCID (% predicted and meters) with different analysis methods and for subgroups of different disease severity for LOPD. METHODS: Data from the PROPEL trial were used to calculate 6MWD MCID in the overall PROPEL population and subgroups of baseline severity as assessed by walking distance and body mass index (BMI), using anchor- and distribution-based approaches. RESULTS: The 6MWD MCIDs varied widely, depending on the method and subgroup, ranging from 2.27%-8.11% predicted for the overall LOPD population (23.7 m-57.2 m). For patients with baseline 6MWD < 150 m, MCIDs ranged from -0.74%-3.37% (-2.1 m-11.3 m). MCIDs increased with distance walked at baseline until a plateau was reached. For BMI subgroups, the MCIDs were generally lowest in obese patients. CONCLUSION: Our analysis shows that MCID depends on the chosen method and disease severity. The findings suggest that applying a single MCID to all patients can be misleading; consequently, a range of possible MCIDs should be considered. This may also be highly relevant for other neuromuscular diseases. This study provides a range of 6MWD MCIDs for LOPD, with lower MCIDs for more severe patients.

Effect of Active Workstations on Neurocognitive Performance and Typing Skills: A Randomized Clinical Trial.

BACKGROUND: Extended sedentary behavior is a risk factor for chronic disease and mortality, even among those who exercise regularly. Given the time constraints of incorporating physical activity into daily schedules, and the high likelihood of sitting during office work, this environment may serve as a potentially feasible setting for interventions to reduce sedentary behavior. METHODS AND RESULTS: A randomized cross-over clinical trial was conducted at an employee wellness center. Four office settings were evaluated on 4 consecutive days: stationary or sitting station on day 1 (referent), and 3 subsequent active workstations (standing, walking, or stepper) in randomized order. Neurocognitive function (Selective Attention, Grammatical Reasoning, Odd One Out, Object Reasoning, Visuospatial Intelligence, Limited-Hold Memory, Paired Associates Learning, and Digit Span) and fine motor skills (typing speed and accuracy) were tested using validated tools. Average scores were compared among stations using linear regression with generalized estimating equations to adjust standard errors. Bonferroni method adjusted for multiple comparisons. Healthy subjects were enrolled (n=44), 28 (64%) women, mean±SD age 35±11 years, weight 75.5±17.1 kg, height 168.5±10.0 cm, and body mass index 26.5±5.2 kg/m2. When comparing active stations to sitting, neurocognitive test either improved or remained unchanged, while typing speed decreased without affecting typing errors. Overall results improved after day 1, suggesting habituation. We observed no major differences across active stations, except decrease in average typing speed 42.5 versus 39.7 words per minute with standing versus stepping (P=0.003). CONCLUSIONS: Active workstations improved cognitive performance, suggesting that these workstations can help decrease sedentary time without work performance impairment. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT06240286.

Validity of an android device for assessing mobility in people with chronic stroke and hemiparesis: a cross-sectional study.

BACKGROUND: Incorporating instrument measurements into clinical assessments can improve the accuracy of results when assessing mobility related to activities of daily living. This can assist clinicians in making evidence-based decisions. In this context, kinematic measures are considered essential for the assessment of sensorimotor recovery after stroke. The aim of this study was to assess the validity of using an Android device to evaluate kinematic data during the performance of a standardized mobility test in people with chronic stroke and hemiparesis. METHODS: This is a cross-sectional study including 36 individuals with chronic stroke and hemiparesis and 33 age-matched healthy subjects. A simple smartphone attached to the lumbar spine with an elastic band was used to measure participants' kinematics during a standardized mobility test by using the inertial sensor embedded in it. This test includes postural control, walking, turning and sitting down, and standing up. Differences between stroke and non-stroke participants in the kinematic parameters obtained after data sensor processing were studied, as well as in the total execution and reaction times. Also, the relationship between the kinematic parameters and the community ambulation ability, degree of disability and functional mobility of individuals with stroke was studied. RESULTS: Compared to controls, participants with chronic stroke showed a larger medial-lateral displacement (p = 0.022) in bipedal stance, a higher medial-lateral range (p < 0.001) and a lower cranio-caudal range (p = 0.024) when walking, and lower turn-to-sit power (p = 0.001), turn-to-sit jerk (p = 0.026) and sit-to-stand jerk (p = 0.001) when assessing turn-to-sit-to-stand. Medial-lateral range and total execution time significantly correlated with all the clinical tests (p < 0.005), and resulted significantly different between independent and limited community ambulation patients (p = 0.042 and p = 0.006, respectively) as well as stroke participants with significant disability or slight/moderate disability (p = 0.024 and p = 0.041, respectively). CONCLUSION: This study reports a valid, single, quick and easy-to-use test for assessing kinematic parameters in chronic stroke survivors by using a standardized mobility test with a smartphone. This measurement could provide valid clinical information on reaction time and kinematic parameters of postural control and gait, which can help in planning better intervention approaches.

Ankle and hindfoot motion of healthy adults during running revealed by dynamic biplane radiography: Side-to-side symmetry, sex-specific differences, and comparison with walking.

This study aimed to characterize ankle and hindfoot kinematics of healthy men and women during overground running using biplane radiography, and to compare these data to those previously obtained in the same cohort during overground walking. Participants ran across an elevated platform at a self-selected pace while synchronized biplane radiographs of their ankle and hindfoot were acquired. Motion of the tibia, talus, and calcaneus was tracked using a validated volumetric model-based tracking process. Tibiotalar and subtalar 6DOF kinematics were obtained. Absolute side-to-side differences in ROM and kinematics waveforms were calculated. Side-to-side and sex-specific differences were evaluated at 10 % increments of stance phase with mixed model analysis. Pearson correlation coefficients were used to assess the relationship between stance-phase running and walking kinematics. 20 participants comprised the study cohort (10 men, mean age 30.8 ± 6.3 years, mean BMI 24.1 ± 3.1). Average absolute side-to-side differences in running kinematics waveforms were 5.6°/2.0 mm or less at the tibiotalar joint and 5.2°/3.2 mm or less at the subtalar joint. No differences in running kinematics waveforms between sides or between men and women were detected. Correlations were stronger at the tibiotalar joint (42/66 [64 %] of correlations were p < 0.05), than at the tibiotalar joint (38/66 [58 %] of correlations were p < 0.05). These results provide a normative reference for evaluating native ankle and hindfoot kinematics which may be informative in surgical or rehabilitation contexts. Sex-specific differences in ankle kinematics during overground running are likely not clinically or etiologically significant. Associations seen between walking and running kinematics suggest one could be used to predict the other.

Evaluation of the accuracy of a UWB tracker for in-home positioning for older adults.

The population of older adults is rapidly growing. In-home monitoring systems have been used to support aging-in-place. Ambient sensors or wearable localizers can be used but may be too low resolution, while camera systems are invasive to privacy. Ultra-wideband (UWB) localization offers precise positioning by placing anchors throughout the house and wearing a tag that is tracked by the anchors. In this study, the accuracy of UWB for indoor tracking was evaluated in a motion capture gait lab and in a mock condo in the Glenrose Rehabilitation Hospital. First, the configuration of UWB was tested, changing factors related to sampling time, anchor placement and line-of-sight. Comparing these factors to the configurations recommended by the manufacturer guidelines, accuracies remained within 14 cm. We then performed static and dynamic accuracy tests, with dynamic testing comprised of rolling and walking motions. In the motion capture lab, we found localization accuracies of 7.0 ± 11.1 cm while in the mock condo, we found accuracies of 27.3 ± 12.9 cm. Dynamic testing with rolling motions had an average of 19.1 ± 1.6 cm while walking was 20.5 ± 4.2 cm. The mean accuracy of UWB is within the 30 cm target for indoor localization.

Inspiratory Training for Improving Respiratory Strength, Pulmonary Function, and Walking in Cerebral Palsy: A Meta-Analysis.

PURPOSE: To investigate the effects of inspiratory strength training on respiratory muscle strength, pulmonary function, and walking capacity in children with cerebral palsy, with Gross Motor Function Classification System I to III. METHODS: Searches were conducted in CINAHL, LILACS, MEDLINE, and Physiotherapy Evidence Database (PEDro) databases. The outcomes of interest were respiratory muscle strength, pulmonary function, and walking capacity. The quality was assessed by PEDro Scale. The Grading of Recommendations Assessment, Development, and Evaluation system was used to summarize the quality of evidence. RESULTS: Inspiratory strength training increased the strength of inspiratory muscles and may increase the strength of the expiratory muscles. No changes were observed in pulmonary function or walking capacity. CONCLUSIONS: This systematic review provides moderate-quality evidence that inspiratory strength training is effective for increasing inspiratory muscle strength in children with cerebral palsy. Benefits may be carried over to improving expiratory muscle strength but were not observed on pulmonary function or walking capacity.

Short communication: Binocular rivalry dynamics during locomotion.

Locomotion has been shown to impact aspects of visual processing in both humans and animal models. In the current study, we assess the impact of locomotion on the dynamics of binocular rivalry. We presented orthogonal gratings, one contrast-modulating at 0.8 Hz (matching average step frequency) and the other at 3.2 Hz, to participants using a virtual reality headset. We compared two conditions: stationary and walking. We continuously monitored participants' foot position using tracking devices to measure the step cycle. During the walking condition, participants viewed the rivaling gratings for 60-second trials while walking on a circular path in a virtual reality environment. During the stationary condition, observers viewed the same stimuli and environment while standing still. The task was to continuously indicate the dominant percept via button press using handheld controllers. We found no significant differences between walking and standing for normalized dominance duration distributions, mean normalized dominance distributions, mean alternation rates, or mean fitted frequencies. Although our findings do not align with prior research highlighting distinctions in normalized dominance distributions between walking and standing, our study contributes unique evidence indicating that alternation rates vary across the step cycle. Specifically, we observed that the number of alternations is at its lowest during toe-off phases and reaches its peak at heel strike. This novel insight enhances our understanding of the dynamic nature of alternation patterns throughout the step cycle.

Noninvasive spinal stimulation improves walking in chronic stroke survivors: a proof-of-concept case series.

BACKGROUND: After stroke, restoring safe, independent, and efficient walking is a top rehabilitation priority. However, in nearly 70% of stroke survivors asymmetrical walking patterns and reduced walking speed persist. This case series study aims to investigate the effectiveness of transcutaneous spinal cord stimulation (tSCS) in enhancing walking ability of persons with chronic stroke. METHODS: Eight participants with hemiparesis after a single, chronic stroke were enrolled. Each participant was assigned to either the Stim group (N = 4, gait training + tSCS) or Control group (N = 4, gait training alone). Each participant in the Stim group was matched to a participant in the Control group based on age, time since stroke, and self-selected gait speed. For the Stim group, tSCS was delivered during gait training via electrodes placed on the skin between the spinous processes of C5-C6, T11-T12, and L1-L2. Both groups received 24 sessions of gait training over 8 weeks with a physical therapist providing verbal cueing for improved gait symmetry. Gait speed (measured from 10 m walk test), endurance (measured from 6 min walk test), spatiotemporal gait symmetries (step length and swing time), as well as the neurophysiological outcomes (muscle synergy, resting motor thresholds via spinal motor evoked responses) were collected without tSCS at baseline, completion, and 3 month follow-up. RESULTS: All four Stim participants sustained spatiotemporal symmetry improvements at the 3 month follow-up (step length: 17.7%, swing time: 10.1%) compared to the Control group (step length: 1.1%, swing time 3.6%). Additionally, 3 of 4 Stim participants showed increased number of muscle synergies and/or lowered resting motor thresholds compared to the Control group. CONCLUSIONS: This study provides promising preliminary evidence that using tSCS as a therapeutic catalyst to gait training may increase the efficacy of gait rehabilitation in individuals with chronic stroke. Trial registration NCT03714282 (clinicaltrials.gov), registration date: 2018-10-18.

GIS-based intelligent planning approach of child-friendly pedestrian pathway to promote a child-friendly city.

Pedestrian safety, particularly for children, relies on well-designed pathways. Child-friendly pathways play a crucial role in safeguarding young pedestrians. Shared spaces accommodating both vehicles and walkers can bring benefits to pedestrians. However, active children playing near these pathways are prone to accidents. This research aims to develop an efficient method for planning child-friendly pedestrian pathways, taking into account community development and the specific needs of children. A mixed-methods approach was employed, utilizing the Datang community in Guangzhou, China, as a case study. This approach combined drawing techniques with GIS data analysis. Drawing methods were utilized to identify points of interest for children aged 2-6. The qualitative and quantitative fuzzy analytic hierarchy process assessed factors influencing pathway planning, assigning appropriate weights. The weighted superposition analysis method constructed a comprehensive cost grid, considering various community elements. To streamline the planning process, a GIS tool was developed based on the identified factors, resulting in a practical, child-friendly pedestrian pathway network. Results indicate that this method efficiently creates child-friendly pathways, ensuring optimal connectivity within the planned road network.

Viability leads to the emergence of gait transitions in learning agile quadrupedal locomotion on challenging terrains.

Quadruped animals are capable of seamless transitions between different gaits. While energy efficiency appears to be one of the reasons for changing gaits, other determinant factors likely play a role too, including terrain properties. In this article, we propose that viability, i.e., the avoidance of falls, represents an important criterion for gait transitions. We investigate the emergence of gait transitions through the interaction between supraspinal drive (brain), the central pattern generator in the spinal cord, the body, and exteroceptive sensing by leveraging deep reinforcement learning and robotics tools. Consistent with quadruped animal data, we show that the walk-trot gait transition for quadruped robots on flat terrain improves both viability and energy efficiency. Furthermore, we investigate the effects of discrete terrain (i.e., crossing successive gaps) on imposing gait transitions, and find the emergence of trot-pronk transitions to avoid non-viable states. Viability is the only improved factor after gait transitions on both flat and discrete gap terrains, suggesting that viability could be a primary and universal objective of gait transitions, while other criteria are secondary objectives and/or a consequence of viability. Moreover, our experiments demonstrate state-of-the-art quadruped robot agility in challenging scenarios.

Minimal detectable change of gait and balance measures in older neurological patients: estimating the standard error of the measurement from before-after rehabilitation data thanks to the linear mixed-effects models.

BACKGROUND: Tracking gait and balance impairment in time is paramount in the care of older neurological patients. The Minimal Detectable Change (MDC), built upon the Standard Error of the Measurement (SEM), is the smallest modification of a measure exceeding the measurement error. Here, a novel method based on linear mixed-effects models (LMMs) is applied to estimate the standard error of the measurement from data collected before and after rehabilitation and calculate the MDC of gait and balance measures. METHODS: One hundred nine older adults with a gait impairment due to neurological disease (66 stroke patients) completed two assessment sessions before and after inpatient rehabilitation. In each session, two trials of the 10-meter walking test and the Timed Up and Go (TUG) test, instrumented with inertial sensors, have been collected. The 95% MDC was calculated for the gait speed, TUG test duration (TTD) and other measures from the TUG test, including the angular velocity peak (ωpeak) in the TUG test's turning phase. Random intercepts and slopes LMMs with sessions as fixed effects were used to estimate SEM. LMMs assumptions (residuals normality and homoscedasticity) were checked, and the predictor variable ln-transformed if needed. RESULTS: The MDC of gait speed was 0.13 m/s. The TTD MDC, ln-transformed and then expressed as a percentage of the baseline value to meet LMMs' assumptions, was 15%, i.e. TTD should be < 85% of the baseline value to conclude the patient's improvement. ωpeak MDC, also ln-transformed and expressed as the baseline percentage change, was 25%. CONCLUSIONS: LMMs allowed calculating the MDC of gait and balance measures even if the test-retest steady-state assumption did not hold. The MDC of gait speed, TTD and ωpeak from the TUG test with an inertial sensor have been provided. These indices allow monitoring of the gait and balance impairment, which is central for patients with an increased falling risk, such as neurological old persons. TRIAL REGISTRATION: NA.

Multifaceted associations between walking performance, physical fitness, extremity function, health status, and depression in individuals with COPD.

BACKGROUND/OBJECTIVE(S): Chronic obstructive pulmonary disease (COPD) can precipitate a deterioration of an individual's physical performance and overall health. Evidence suggests that, along with pulmonary functions, several other factors are related to the significant impairment of walking performance in individuals with COPD. This study compared the depressive symptoms, health status, upper and lower extremity functions, and peak oxygen uptake (VO2peak) in a group of individuals with COPD based on walking performance using a cutoff distance of 350 m in the six-minute walking test (6MWT). The study also investigated the associations between these factors and walking performance. MATERIALS AND METHODS: Participants performed the 6MWT according to the guidelines and were classified into high (>350 m; n = 40) or low (<350 m; n = 30) walking performance groups according to distance. The forced expiratory volume (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio were recorded. Participants completed the Patient Health Questionnaire-9 (PHQ-9), St. George's Respiratory Questionnaire (SGRQ), and the Upper and Lower Extremity Functional Index (UEFI/LEFI). Predicted VO2peak was measured using the Duke Activity Status Index (DASI). RESULTS: Seventy participants with a mean age of 63 ± 11 years (20% female) were enrolled in this study. Patients with high walking performance demonstrated significantly better health status than those with low walking performance (SGRQ: 49 ± 25 vs. 56 ± 21, p = 0.03). Participants with low walking performance had lower predicted VO2peak compared to their higher performing counterparts (p = 0.002). The overall model was significant (F(8, 61) = 7.48, p = 0.0006), with PHQ-9, SGRQ, UEFI/LEFI, VO2peak, and FEV1/FVC explaining approximately 49.5% of the variance in the 6MWT distance. CONCLUSION: This study shed light on the association of depressive symptoms, health status, extremity function, and VO2peak with walking performance, providing valuable insights that may impact the management and care of individuals with COPD.

COPD is a global health issue that significantly impairs physical performance, particularly walking.Depressive symptoms, health status, extremity function, and predicted peak oxygen uptake can predict walking performance in patients with COPD, offering insight into potential interventions.

Learning agile soccer skills for a bipedal robot with deep reinforcement learning.

We investigated whether deep reinforcement learning (deep RL) is able to synthesize sophisticated and safe movement skills for a low-cost, miniature humanoid robot that can be composed into complex behavioral strategies. We used deep RL to train a humanoid robot to play a simplified one-versus-one soccer game. The resulting agent exhibits robust and dynamic movement skills, such as rapid fall recovery, walking, turning, and kicking, and it transitions between them in a smooth and efficient manner. It also learned to anticipate ball movements and block opponent shots. The agent's tactical behavior adapts to specific game contexts in a way that would be impractical to manually design. Our agent was trained in simulation and transferred to real robots zero-shot. A combination of sufficiently high-frequency control, targeted dynamics randomization, and perturbations during training enabled good-quality transfer. In experiments, the agent walked 181% faster, turned 302% faster, took 63% less time to get up, and kicked a ball 34% faster than a scripted baseline.

Increasing physical activity among older adults with gynecologic cancers: a qualitative study.

PURPOSE: The purpose of this study was to gain an understanding of older gynecologic cancer patients' preferences and opinions related to physical activity during chemotherapy, including interventions to promote physical activity. METHODS: Gynecologic cancer patients 60 years or older receiving chemotherapy at a single institution within the last 12 months completed questionnaires and a semi-structured interview asking about their preferences for physical activity interventions aimed at promoting physical activity while receiving treatment. RESULTS: Among the 30 gynecologic cancer patients surveyed and interviewed, a majority agreed with the potential usefulness of a physical activity intervention during chemotherapy (67%) and most reported they would be willing to use an activity tracker during chemotherapy (73%). They expressed a preference for an aerobic activity intervention such as walking, indicated a desire for education from their clinical team on the effects physical activity can have on treatment symptoms, and stated a need for an intervention that could be accessed from anywhere and anytime. Additionally, they emphasized a need for an intervention that considered their treatment symptoms as these were a significant barrier to physical activity while on chemotherapy. CONCLUSION: In this study of older gynecologic cancer patients receiving chemotherapy, most were open to participating in a virtually accessible and symptom-tailored physical activity intervention to promote physical activity during chemotherapy.

Square-stepping exercise in older inpatients in early geriatric rehabilitation. A randomized controlled pilot study.

BACKGROUND: Preservation of mobility and fall prevention have a high priority in geriatric rehabilitation. Square-Stepping Exercise (SSE) as an evaluated and standardized program has been proven to be an effective training for older people in the community setting to reduce falls and improve subjectively perceived health status. This randomized controlled trial (RCT), for the first time, examines SSE in the context of inpatient early geriatric rehabilitation compared to conventional physiotherapy (cPT). METHODS: Data were collected in a general hospital in the department of acute geriatric care at admission and discharge. Fifty-eight inpatients were randomized to control (CG, n = 29) or intervention groups (IG, n = 29). CG received usual care with cPT five days per week during their hospital stay. For the IG SSE replaced cPT for at least six sessions, alternating with cPT. Physical function was measured with the Short Physical Performance Battery (SPPB) and Timed "Up & Go" (TUG). Gait speed was measured over a distance of 10 m. In a subgroup (n = 17) spatiotemporal gait parameters were analyzed via a GAITRite® system. RESULTS: Both the SPPB total score improved significantly (p = < 0.001) from baseline to discharge in both groups, as did the TUG (p < 0.001). In the SPPB Chair Rise both groups improved with a significant group difference in favor of the IG (p = 0.031). For both groups gait characteristics improved: Gait speed (p = < 0.001), walk ratio (p = 0.011), step length (p = < 0.001), stride length (p = < 0.001) and double support (p = 0.009). For step length at maximum gait speed (p = 0.054) and stride length at maximum gait speed (p = 0.060) a trend in favor of the IG was visible. CONCLUSIONS: SSE in combination with a reduced number of sessions of cPT is as effective as cPT for inpatients in early geriatric rehabilitation to increase physical function and gait characteristics. In the Chair Rise test SSE appears to be superior. These results highlight that SSE is effective, and may serve as an additional component for cPT for older adults requiring geriatric acute care. TRIAL REGISTRATION: DRKS00026191.

Real-world data capture of daily limb loading using force-sensing insoles: Feasibility and lessons learned.

Force-sensing insoles are wearable technology that offer an innovative way to measure loading outside of laboratory settings. Few studies, however, have utilized insoles to measure daily loading in real-world settings. This is an ancillary study of a randomized controlled trial examining the effect of weight loss alone, weight loss plus weighted vest, or weight loss plus resistance training on bone health in older adults. The purpose of this ancillary study was to determine the feasibility of using force-sensing insoles to collect daily limb loading metrics, including peak force, impulse, and loading rate. Forty-four participants completed a baseline visit of three, 2-minute walking trials while wearing force-sensing insoles. During month two of the intervention, 37 participants wore insoles for 4 days for 8 waking hours each day. At 6-month follow-up, participants completed three, two-minute walking trials and a satisfaction questionnaire. Criteria for success in feasibility was defined as: a) > 60 % recruitment rate; b) > 80 % adherence rate; c) > 75 % of usable data, and d) > 75 % participant satisfaction. A 77.3 % recruitment rate was achieved, with 44 participants enrolled. Participants wore their insoles an average of 7.4 hours per day, and insoles recorded an average of 5.5 hours per day. Peak force, impulse, and loading rate collected at baseline and follow-up were 100 % usable. During the real-world settings, 87.8 % of data was deemed usable with an average of 1200 min/participant. Lastly, average satisfaction was 80.5 %. These results suggest that force-sensing insoles appears to be feasible to capture real-world limb loading in older adults.

The impact of pediatric obesity on biomechanical differences across the gait cycle at three walking speeds.

BACKGROUND: Obesity impacts a child's ability to walk with resulting biomechanical adaptations; however, existing research has not comprehensively compared differences across the gait cycle. We examined differences in lower extremity biomechanics across the gait cycle between children with and without obesity at three walking speeds. METHODS: Full gait cycles of age-matched children with obesity (N = 10; BMI: 25.7 ± 4.2 kg/m2) and without obesity (N = 10; BMI: 17.0 ± 1.9 kg/m2) were analyzed at slow, normal, and fast walking speeds. Main and interaction effects of group and speed across hip, knee, and ankle joint angles and moments in sagittal, frontal, and transverse planes were analyzed using one-dimensional statistical parametric mapping. FINDINGS: Compared to children without obesity, children with obesity had greater hip adduction during mid-stance, while also producing greater hip extensor moments during early stance phase, abductor moments throughout most of stance, and hip external rotator moments during late stance. Children with obesity recorded greater knee flexor, knee extensor and knee internal rotator moments during early stance, and knee external rotator moments in late stance than children without obesity; children with obesity also demonstrated greater ankle plantarflexor moments throughout mid and late stance. Interaction effects existed within joint kinetics data; children with obesity produced greater hip extensor moments at initial contact and toe-off when walking at fast compared to normal walking speed. INTERPRETATION: While few kinematic differences existed between the two groups, children with obesity exhibited greater moments at the hip, knee, and ankle during critical periods of controlling and stabilizing mass.

Trial- vs. cycle-level detrending in the analysis of cyclical biomechanical data.

Biomechanical time series may contain low-frequency trends due to factors like electromechanical drift, attentional drift and fatigue. Existing detrending procedures are predominantly conducted at the trial level, removing trends that exist over finite, adjacent time windows, but this fails to consider what we term 'cycle-level trends': trends that occur in cyclical movements like gait and that vary across the movement cycle, for example: positive and negative drifts in early and late gait phases, respectively. The purposes of this study were to describe cycle-level detrending and to investigate the frequencies with which cycle-level trends (i) exist, and (ii) statistically affect results. Anterioposterior ground reaction forces (GRF) from the 41-subject, 8-speed, open treadmill walking dataset of Fukuchi (2018) were analyzed. Of a total of 552 analyzed trials, significant cycle-level trends were found approximately three times more frequently (21.1%) than significant trial-level trends (7.4%). In statistical comparisons of adjacent walking speeds (i.e., speed 1 vs. 2, 2 vs. 3, etc.) just 3.3% of trials exhibited cycle-level trends that changed the null hypothesis rejection decision. However 17.6% of trials exhibited cycle-level trends that qualitatively changed the stance phase regions identified as significant. Although these results are preliminary and derived from just one dataset, results suggest that cycle-level trends can contribute to analysis bias, and therefore that cycle-level trends should be considered and/or removed where possible. Software implementing the proposed cycle-level detrending is available at https://github.com/0todd0000/detrend1d.