Search Results (351)

With the development of inspection robot control technology, wheel-legged robots are increasingly used in complex underground space inspection. To address low stability during obstacle crossing in unstructured terrains, a motion control strategy integrating an improved CPG algorithm and a biological reflex mechanism is proposed. It introduces an adaptive coupling matrix, augmented with the Lyapunov function, and vestibular/stumbling reflex models for real-time motion feedback. Simulink–Adams virtual prototypes and single-wheeled leg experiments (on the left front leg) were used to verify the system. Results show that the robot’s turning oscillation was ≤±0.00593 m, the 10° tilt maintained a stable center of mass at 10.2° with roll angle fluctuations ≤±5°, gully-crossing fluctuations ≤±0.01 m, and pitch recovery ≤2 s. The experiments aligned with the simulations, proving that the strategy effectively suppresses vertical vibrations, ensuring stable and high-precision inspection. Full article

Background: The waist–calf circumference ratio (WCR) is an index that combines waist and calf circumference measurements, offering a potentially effective method for evaluating the imbalance between abdominal fat and leg muscle mass in older adults. Objective: To assess the association between WCR and indicators of body composition, muscle strength, and physical performance in community-dwelling older women. Methods: This was a cross-sectional study involving 133 older women (≥65 years) from an urban-marginal community in Guayaquil, Ecuador. The WCR was categorized into quartiles (Q1: 2.07–2.57; Q2: 2.58–2.75; Q3: 2.76–3.05; Q4: 3.06–4.76). Body indicators included fat-free mass (FFM), skeletal muscle mass (SMM), appendicular muscle mass (ASM), appendicular muscle mass index (ASMI), visceral fat (VF), fat mass (FM), and fat mass index (FMI). Handgrip strength (HGS) and the Short Physical Performance Battery test (SPPB) score were used to assess muscle strength and function, respectively. Results: The median age of the participants was 75 [IQR: 65–82] years. The mean WCR was 2.92 ± 0.93. Statistically significant associations were found between WCR and VF (p < 0.001), WCR and SMM (p = 0.039), and WCR and ASM (p = 0.016). Regarding muscle function, WCR was associated with HGS (p = 0.025) and SPPB score (p = 0.029). Conclusions: A significant association was observed between WCR and body composition, and muscle strength and function in older women. Full article

The mental and physical health of college students, especially in urban environments like Shanghai, is crucial given the high academic and urban stressors, which were intensified by the COVID-19 lockdown. Prior research has shown gender differences in health impacts during public health crises, with females often more vulnerable to mental health issues. Objective: This study aimed to comprehensively assess the physical and psychological health of Chinese college students post-lockdown, focusing on the relationship between stress, anxiety, depression, sleep patterns, and physical health, with a particular emphasis on gender differences. Methods: We conducted a cross-sectional study involving 116 students in Shanghai, utilizing psychological scales (HAMA, IPAQ, PSQI, SDS, FS 14, PSS, SF-36) and physical fitness tests (resting heart rate, blood pressure, hand grip, forced vital capacity, standing long jump, sit-and-reach, one-minute sit-up test and the one-minute squat test, single-leg stand test with eyes closed), to analyze health and behavior during the pandemic lockdown. All students have undergone the same life habits during the pandemic. Results: The HAMA scores indicated no significant levels of physical or mental anxiety. The PSS results (42.45 ± 8.93) reflected a high overall stress level. Furthermore, the PSQI scores (5.4 ± 2.91) suggested that the participants experienced mild insomnia. The IPAQ scores indicated higher levels of job-related activity (1261.49 ± 2144.58), transportation activity (1253.65 ± 987.57), walking intensity (1580.78 ± 1412.20), and moderate-intensity activity (1353.03 ± 1675.27) among college students following the lockdown. Hand grip strength (right) (p = 0.001), sit-and-reach test (p = 0.001), standing long jump (p = 0.001), and HAMA total score (p = 0.033) showed significant differences between males and females. Three principal components were identified in males: HAMA, FS14, and PSQI, explaining a total variance of 70.473%. Similarly, three principal components were extracted in females: HAMA, PSQI, and FS14, explaining a total variance of 69.100%. Conclusions: Our study underscores the complex interplay between physical activity (PA), mental health, and quality of life, emphasizing the need for gender-specific interventions. The persistent high stress, poor sleep quality, and reduced PA levels call for a reorganized teaching schedule to enhance student well-being without increasing academic pressure. Full article

Background: This study examines balance, flexibility and self-esteem among healthy individuals who engage in surfing compared to those who do not surf. Methods: A cross-sectional study design was conducted with 124 participants divided into the following groups: Group 1: Surfers n = 42; Group 2: individuals performing over 3 h of physical activity per week n = 43; and Group 3: individuals performing fewer than 3 h of physical activity per week n = 39. To assess balance, the Star Excursion Balance Test (SEBT) and the Flamenco Test (FBT) were used, the sit-and-reach test (SRT) was used to measure hamstring extensibility, the Rosenberg Scale was used to measure self-esteem, and the International Physical Activity Questionnaire (IPAQ) was used to measure physical activity levels. Results: Regarding descriptive characteristics, G1 participants were significant older than those of G2 and G3 (p < 0.05 and p < 0.001, respectively). Moreover, there was a higher proportion of females in G3 than in G1 and G2 (p < 0.05). The results revealed significant differences in balance between the surfers and those engaging in fewer than 3 h of activity per week (p < 0.05). G1 obtained significantly higher results in SEBT-left leg than G2 and G3 (p < 0.001) and higher result in SEBT-right leg and FBT than G3 (p < 0.05) but no significant differences in self-esteem were found. Significant differences in flexibility were observed between males and females (p < 0.001). Conclusions: This result suggests that surfing could have a positive effect on balance. Full article

Background: Gait impairments are common in individuals with knee osteoarthritis awaiting total knee arthroplasty, affecting their mobility and quality of life. This study aimed to assess and compare biomechanical gait features between individuals awaiting total knee arthroplasty and healthy, non-arthritic controls, focusing on less-explored variables using sensor-based measurements. Methods: A cross-sectional observational study was conducted with 60 participants: 21 individuals awaiting total knee arthroplasty and 39 nonarthritic controls aged 64–85 years. Participants completed a standardized 14 m walk, and 17 biomechanical gait parameters were measured using the BTS G-Walk inertial sensor. Key variables, such as stride duration, cadence, symmetry indices, and pelvic angles, were analyzed for group differences. Results: The pre-total knee arthroplasty group exhibited significantly longer gait cycles and stride durations (p < 0.001), reduced cadence (p < 0.001), and lower gait cycle symmetry index (p < 0.001) than the control group. The pelvic angle symmetry indices for tilt (p = 0.014), rotation (p = 0.002), and obliquity (p < 0.001) were also lower. Additionally, the pre-total knee arthroplasty group had lower propulsion indices for both legs (p < 0.001) and a lower walking quality index on the right leg (p = 0.005). The number of elaborated steps was significantly greater in the pre-total knee arthroplasty group (left, p < 0.001, right: p < 0.001). No significant differences were observed in any other gait parameters. Conclusions: This study revealed significant gait impairment in individuals awaiting total knee arthroplasty. Although direct evidence for prehabilitation is lacking, future research should explore whether targeted approaches, such as strengthening exercises or gait retraining, can improve gait and functional outcomes before surgery. Full article

Wheelchair basketball (WB) grants important benefits for people with disabilities but also presents a relevant risk of injury. Wheelchair straps are restraint devices that can improve safety and performance, but limited research has explored their use in WB. This study aims to analyze the use of different types of straps among professional WB players, according to classification score. A cross-sectional study was conducted through an online survey. Participants were divided into two groups based on classification score: low-point players (LPPs; 1.0–2.5), who have greater physical impairment, and high-point players (HPPs; 3.0–4.5), who have lower physical impairment. A total of 82 WB players participated (43 LPPs; 39 HPPs). The Chi-squared test was used to compare variables between groups. Significant differences emerged: chest (p = 0.036), abdominal (p = 0.036), and foot (p = 0.016) straps were more frequently used by LPPs, while thigh (p = 0.020) and leg (p = 0.050) straps were more common among HPPs. No significant difference was found for pelvic strap. Straps used in WB vary with classification score, reflecting the influence of functional ability. These findings offer insights into individualized wheelchair setup and classification procedures. Further studies are needed to expand knowledge on this topic. Full article

Background/Objectives: Power indices may provide valuable information for performance and injury prevention in soccer players, so increasing the knowledge about them seems essential. Therefore, this study aimed to establish limb-specific normative values for flywheel-derived power indices in professional soccer players, while accounting for limb performance or ability, to explore the relationships between power indices across variables and to compare the power outcomes related to these indices between injured and non-injured players within four months post-assessment. Methods: Twenty-two male professional soccer players (age: 26.6 ± 4.6 years; competitive level: Belgian second division) were recruited from a single elite-tier club to participate in this cross-sectional diagnostic study. Participants underwent a standardized assessment protocol, executed in a rotational inertial device, comprising six unilateral exercises focused on the lower limbs: hip-dominant quadriceps (Qhip), knee-dominant quadriceps (Qknee), hip-dominant hamstrings (Hhip), knee-dominant hamstrings (Hknee), adductor (Add), and abductor (Abd). The testing session incorporated a randomized, counterbalanced design, with each exercise comprising two sets of eight maximal concentric–eccentric repetitions per limb. Leg dominance was operationally defined as the self-reported preferred limb for ball-striking tasks. Power indices were calculated from these exercises. Results: No significant differences in flywheel-derived power indices were found between limbs or between injured and non-injured players. However, significant correlations between indices were found in all power variables, with the Qhip:Qknee and Hhip:Hknee concentric ratios emerging as the most clinically actionable biomarkers for rapid screening. Conclusions: These results suggest the necessity of including more variables for injury prediction. Moreover, power indices could be considered based on the classification of limbs as “strong” or “weak”. Full article

Background: Despite the high incidence of surgical treatment of lower leg fractures in children, there is little research focusing on the emotional consequences of such trauma, particularly the distinction between somatic and cognitive anxiety symptoms. Given the important role of social support and manifest anxiety in emotional recovery, there is a clear need to investigate factors that predict the development of anxiety in this population. Objectives: This study aimed to identify predictors of anxiety and to assess differences between somatic and cognitive anxiety symptoms in children undergoing surgery for lower leg fractures, addressing the need to better understand psychological effects in this vulnerable group. Methods: The research included 63 children with lower leg fractures, of whom 40 were boys (63.5%) and 23 were girls (36.5%), with a mean age of M = 15.174 (SD = 3.701). The instruments used in this research were as follows: the Demographic Data Questionnaire, the Children’s Anxiety Scale, the Beck Anxiety Inventory (BAI), and the Multidimensional Scale of Perceived Social Support. Results: The results showed that the only significant predictor of somatic symptoms of anxiety was the presence of paresthesia, while significant predictors of cognitive symptoms of anxiety were social support from friends and the presence of paresthesia. Conclusions: Paresthesia was identified as a significant predictor of somatic symptoms of anxiety, while social support from friends was associated with lower levels of cognitive anxiety symptoms in children with lower leg and ankle fractures. These results point to the relevance of considering both somatic and psychological factors in the recovery process following pediatric fractures. Full article

Alkaline phosphatase (ALP) deficiency has been linked to reduced physical performance, as seen in hypophosphatasia (HPP). However, its potential role in muscle function has not been fully explored. This was a cross-sectional study in 34 HPP adults and 34 matched healthy controls. Muscle strength was assessed using handgrip strength (HGS), considering values below the 10th percentile of the Spanish population as low strength. Muscle mass was evaluated using dual-energy X-ray absorptiometry and morphometric ultrasound. Bone mineral density (BMD) was measured at the lumbar spine, femoral neck, and total hip. The prevalence of low muscle strength was significantly higher in the HPP group compared to controls (30% vs. 6%; p = 0.009), with decreased HGS in the HPP group (p = 0.039). Positive associations were observed between ALP and femoral neck BMD, leg circumference, and fat-free mass and an inverse association with tricipital skinfold. Subjects with serum ALP activity below the sex-adjusted median had a significantly higher risk of low muscle strength independently of HPP diagnosis. ALP remained independently associated with HGS (p = 0.005), and a predictive model using ALP values showed strong capability to predict low-muscle-strength risk. Based on these results, we conclude circulating ALP levels are independently associated with muscle strength and may represent a useful biomarker for the early detection of muscle dysfunction. Future longitudinal or interventional studies are needed to assess whether ALP plays a causal role in muscle strength. Full article

Background: Active play has been proposed to complement school-based physical activity (PA) and promote increased movement-related activities relevant for the development of motor competence. Guided active play (GAP) paired with cooperative games provides sufficient moderate-to-vigorous physical activity (MVPA) to improve motor competence for younger children. Whether guided active play exhibits physical activity outputs that are related to motor competence is uncertain. This study assessed the strength of relationships between play-based physical activity and movement skills by comparing linear regression and chi-square analyses. Methods: Forty-two children (Mage = 8.8 ± 0.8 years) participated in a community center program. PA was measured via accelerometry for GAP, alongside assessments of anthropometrics, fitness (leg power, strength, VO₂max), and FMS (Test of Gross Motor Development-2). Multiple linear regression analysis examined reciprocal relationships. Chi-square and cross-tabulations analyzed categorical variables based on lab percentiles (low < 33%, high > 66%) for PA energy expenditure (PAEE), intensity (MVPA), FMS, and fitness. Results: GAP MVPA and object control skills (OC) showed positive reciprocal pathways (β = 0.308, β = 0.394; p ≤ 0.05). VO₂max predicted MVPA (β = 0.408; p < 0.01), with leg power related to PAEE (β = 0.456; p ≤ 0.01). Chi-square analysis revealed significant associations between high OC skills and high PAEE (X² = 15.12, p ≤ 0.05), and high individual average scores of OC with high MVPA (X² = 11.90, p < 0.05. The high performance of AP and LP was associated with MVPA and PAEE, respectively. Conclusions: Findings support a positive feedback loop between MVPA and OC skills for GAP. GAP is an effective strategy for program interventions for children 8 to 10-year old. Full article

Study Design: Pilot randomized clinical trial. Objective: To examine the effect of electrically evoked muscle hypertrophy on indices of spasticity, as measured by Biodex after spinal cord injury (SCI). Setting: Medical research center. Methods: Thirteen males with chronic SCI were randomized into sixteen weeks of either surface neuromuscular resistance training (NMES-RT) + testosterone treatment (TT) (n = 7) or a TT-only group (n = 6). A Biodex isokinetic dynamometer was used to measure knee extensor and flexor muscle spasticity at the beginning (baseline; BL) and at the end (post-intervention; PI) of 16 weeks. The passive tension of the right knee extensor and flexor muscle groups were evaluated at angles of 5°, 30°, 60°, 90°, 180°, and 270° per second (sec). Dual energy X-ray absorptiometry and magnetic resonance imaging were used to measure leg lean mass and thigh muscle cross-sectional areas (CSAs). Results: Robust muscle hypertrophy was noted in leg lean mass [11%, p = 0.023] as well as whole thigh [17%, p = 0.001] and knee extensor muscle [28%, p = 0.001] CSAs in the NMES-RT+TT compared to the TT-only group. There was no difference in extensor or flexor spasticity between the NMES-RT+TT or TT-only groups at different angular velocities following 16 weeks of intervention. Collapsing the extensor passive torques indicated an (24–28%) increase (p < 0.004) in response to angular velocities at BL and following PI measurements [180 deg/sec (23%; p = 0.03) and 270 deg/sec (32%; p = 0.009)] compared to 5 deg/sec. The extensor slope showed a non-significant (p > 0.05) decrease of 15–28% across all angular velocities. The catch-AB slopes were non-significantly lower in the TT-only group compared to the NMES-RT+TT at higher speeds [90 deg/sec and 270 deg/sec] and attained a trend towards lower passive torque at 180 deg/sec [180 deg/sec: 15.5%, p = 0.05]. Conclusions: Evoking skeletal muscle hypertrophy did not increase spasticity indices at different angular velocities following sixteen weeks of NMES-RT+TT or TT in persons with chronic SCI. Augmenting muscle hypertrophy is likely to attenuate the hyper reflexive slope of the extensor spasticity. The findings may suggest that evoking muscle hypertrophy following NMES-RT does not increase indices of spasticity after SCI. The clinical implications are highly important in managing spasticity after SCI. Full article

(1) Background: When implementing new biomechanical and technology-based assessments, such as the jump assessment in Multiple Sclerosis (MS), into clinical routine, it is important to ensure that they are based on the real needs of patients and to identify and adapt to potential barriers early on. (2) Methods: In the present cross-sectional study, 157 pwMS performed a sensor-based jump assessment on a force plate consisting of three jump tests: 10 s jump test (10SHT), countermovement jumps (CMJ), and single-leg countermovement jumps (SLCMJ). After the jump assessment, the patient experience measures (PREM) were recorded using a paper-based questionnaire on an 11-point scale from 0 (positive) to 10 (negative). (3) Results: PwMS showed an overall positive experience with the sensor-based jump assessment. “Staff support performance”, “acceptance required time”, “usefulness” of the results, and “integration of results in therapy” were the best rated items with a median of 0 (positive). The CMJ was perceived as the easy (p < 0.05) and less exhausting (p < 0.05). PwMS who experienced CMJ as easy, not exhausting, and safe were associated with higher CMJ performance, especially in peak power, flight time, and jump height (r > −0.4). Significant associations were found between PREMs and age, sex, BMI, physical activity, and disability degree. (4) Conclusions: The study findings support the feasibility of jump assessment in clinical practice and highlight the need for patient-centered integration of innovative technologies to optimize precision neuromuscular function evaluation in MS. Full article

Background and Objectives: Low back pain (LBP) is a leading cause of disability worldwide. Core stabilization exercises such as the plank are often prescribed in rehabilitation settlings to improve neuromuscular control and spinal support. However, it remains unclear whether plank performance -accurately reflects trunk function or disability in individuals with LBP. The purpose of this study was to evaluate the relationship between plank endurance and low back pain in adults. Methods: A cross-sectional study was conducted with 117 adults aged 20–61 years (mean 26.0 ± 9.3), including both individuals with and without LBP. Participants completed a plank endurance test and the Modified Oswestry Disability Index (MODI). A subset of fifty-four participants with LBP also completed single-leg bridge tests to assess posterior chain endurance. Statistical analyses included Mann–Whitney U tests to compare plank times by LBP status, logistic regression to evaluate predictors of LBP, and correlation analyses to examine associations between the bridge-to-plank ratio and MODI scores. Results: Contrary to the initial hypothesis, individuals with LBP demonstrated significantly longer plank hold times than those without (U = 1861.00, p = 0.036). Logistic regression indicated that the overall model was statistically significant (χ² = 12.39, p = 0.030), but plank duration was not an independent predictor of LBP (p = 0.070). Among participants with LBP, a higher bridge-to-plank ratio, reflecting relatively greater posterior chain endurance, was significantly associated with lower disability scores (Pearson r = −0.31, p = 0.023; Spearman ρ = −0.32, p = 0.018). Conclusions: These findings suggest that, while plank duration differs by LBP status, longer plank times may not indicate lower risk or severity of back pain. A greater balance of posterior chain to anterior core endurance may be more intricately linked to reduced disability, highlighting the importance of comprehensive core assessment and training strategies in rehabilitation. Full article

To investigate the failure evolution and structural response of transmission towers under the combined effects of foundation sliding and wind loads, this study used the foundation sliding incident of Tower No. 39 on the Xiaoxing transmission line as a case for numerical back-analysis. A transmission tower model was first developed based on the finite element method, and the simulation results were compared with field observations to validate the model, with particular focus on the consistency of typical failure modes such as leg bending and cross-bracing instability. On this basis, the structural response under the combined action of foundation lateral displacement, settlement, and wind loads was further simulated. The results indicate that foundation sliding significantly affects the structural stability of transmission towers, with single-foundation sliding being more destructive than the simultaneous sliding of multiple foundations on the same side. Moreover, the coupling of foundation sliding and wind load substantially reduces the critical displacement required to trigger structural failure. Finally, critical displacement thresholds are proposed, which can serve as reference criteria for damage assessment and engineering intervention when changes in foundation conditions occur. Full article

Background/Objectives: Morphological spinal alterations in adolescents, including idiopathic scoliosis (IS) and postural scoliotic attitudes (paramorphisms), may be associated with leg length discrepancy (LLD) and breast asymmetry (BA). This study aimed to assess the prevalence and characteristics of LLD and BA in adolescents with spinal paramorphisms and dysmorphisms (IS), and to explore associations between these asymmetries and spinal curve features. Methods: A cross-sectional observational study was conducted. Adolescents aged 10–18 years were included. LLD was measured clinically via direct tape measurement and, when necessary, ultrasound. BA was assessed via visual inspection. Spinal deformities were characterized via clinical and radiological examination. Results: Among the 44 participants, 26 (60%) had IS and 18 (40%) had postural scoliotic attitudes. LLD was present in 79.5% (mean 0.7 ± 0.6 cm; all mild). BA was observed in 14% of the sample. LLD was more frequent in IS (87%) than in postural scoliotic attitudes (72%). In lumbar postural curves, the shorter limb was consistently ipsilateral to the curve convexity. In IS, no consistent association was found between LLD and curve characteristics. BA was slightly more prevalent in IS (19%) than postural scoliotic attitudes (17%), with no consistent pattern relative to curve convexity. Conclusions: Mild LLD is common in adolescents with spinal asymmetries and reflects general population norms. While LLD may influence compensatory postural curves, it does not appear to affect IS curve patterns or severity. BA is more frequent in IS, but shows variable association with curve features. Considering LLD and BA prevalence in adolescents with spinal asymmetries routine assessment is warranted, though their impact on IS progression is limited. Full article