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The unusual combination of the fundamentally contradictory properties of high tensile strength and high fracture toughness found in maraging steel makes it well suited for safety-critical applications that require high strength-to-weight materials. In certain instances, additive manufacturing (AM) has produced materials that may be desirable for safety-critical applications where impact toughness is a key property, such as structural parts for the aerospace industry or armor plates for military applications. Understanding the influence of process parameters and defect structure on the properties of maraging steel parts produced via laser powder bed fusion (LPBF) is a fundamental step towards the broader use of AM technologies for more demanding applications. In this research, the impact energy of V-notched specimens made of 1.2709 maraging steel produced by LPBF was determined via Charpy impact testing. Specimens were produced using different processing parameter sets. By combining the process parameters with the porosity values of the parts, we demonstrate that an almost full prediction of the impact properties can be achieved, paving the way for significantly reducing the expenses of destructive testing. [ABSTRACT FROM AUTHOR]

Background: Pes cavus is a multiplanar foot deformity with an abnormal plantar pressure distribution and an overhigh medial longitudinal arch (MLA). Its causes are complex. In the past, people have usually focused on clinical surgery for pes cavus. However, this is not necessarily the best choice for some patients with non-ongoing or mild symptoms. In the 21st century, studies have just begun to focus on assistive devices intervention for pes cavus, which has been proven to be an effective non-surgical treatment. However, the effectiveness of assistive devices for patients with arched feet of any etiology has not been evaluated and evidence-based guidelines for clinical treatment options are lacking. Methods: A systematic review and network meta-analysis were performed, employing a comprehensive search across the databases of Web of Science, PubMed, as well as Scopus. The selected studies adhered to specific eligibility criteria, which included: (1) involving patients with pes cavus; (2) interventions with assistive devices; and (3) outcome measures of plantar pressure distribution and anatomical characteristics (MLA). Meanwhile, the standard mean difference was selected as the effect size. Results: A total of three studies were selected, and the authors achieved an agreement on the risk of bias with a kappa value equal to 0.74. According to the results of network meta-analysis, customized foot orthotics compared to other devices (lace-up ankle-support brace, semirigid brace) demonstrated the highest likelihood of being the most effective in optimizing plantar-pressure distribution among pes cavus patients. On the other hand, wearing hard custom foot orthotics compared to other devices (soft custom foot orthotics, off-the-shelf orthotics) showed the greatest potential in improving the medial longitudinal arch (MLA) of pes cavus patients. Discussion: Although becoming better than wearing regular footwear, wearing lace-up ankle-support braces or semirigid braces might not be optimal choices for treatments of pes cavus with the potential mechanism that the internal force created by the fixation of the proximal joint might be much less than the ground reaction force loaded on the distal segments that touch the ground. It could be concluded that foot orthotics show great potential in treating pes cavus under non-surgical conditions. This systematic review could provide valuable evidence for future research and clinical practice. Other: The PROSPERO Registration Number is CRD42022349687.

Payloads for light unmanned free balloons must meet several safety requirements such as being able to protect the inner electronics in order to extract scientific data and to reduce the chance of inflicting personal injury in case of an accidental fall. This article proposes a novel payload structure, which exhibits the form of a dodecahedron. The actual form was determined by carrying out theoretical drop tests on different polyhedrons using the finite element method (FEM). From the simulations, it could be deduced that the dodecahedron was the optimal choice, since the duration of the impact was longer, while the impact force was slightly lower. The payload was produced by additive technologies; therefore, after performing tensile tests on probable materials, PLA was selected as the optimal candidate. The theoretical results about the dodecahedron's ability were validated by laboratory and real-life drop tests, where the new payload was subjected to 56% less impact force under a 78% longer collision time compared to a classic, rectangular cuboid design. Based on these tests, it was demonstrated that the new structure is safer and it is applicable. [ABSTRACT FROM AUTHOR]

Background. Detecting fatigue at the early stages of a run could aid training programs in making adjustments, thereby reducing the heightened risk of injuries from overuse. The study aimed to investigate the effects of running fatigue on plantar force distribution in the dominant and nondominant feet of amateur runners. Methods. Thirty amateur runners were recruited for this study. Bilateral time-series plantar forces were employed to facilitate automatic fatigue gait recognition using convolutional neural network (CNN) and CNN-based long short-term memory network (ConvLSTM) models. Plantar force data collection was conducted both before and after a running-induced fatigue protocol using a FootScan force plate. The Keras library in Python 3.8.8 was used to train and tune deep learning models. Results. The results demonstrated that more mid-forefoot and heel force occurs during bilateral plantar and less midfoot fore force occurs in the dominant limb after fatigue (p < 0.001). The time of peak forces was significantly shortened at the midfoot and sum region of the nondominant foot, while it was delayed at the hallux region of the dominant foot (p < 0.001). In addition, the ConvLSTM model showed higher performance (Accuracy = 0.867, Sensitivity = 0.874, and Specificity = 0.859) in detecting fatigue gait than CNN (Accuracy = 0.800, Sensitivity = 0.874, and Specificity = 0.718). Conclusions. The findings of this study could offer empirical data for evaluating risk factors linked to overuse injuries in a single limb, as well as facilitate early detection of fatigued gait. [ABSTRACT FROM AUTHOR]

Nowadays, there are numerous new features available in CFD (computational fluid dynamics) that can simulate complex physical phenomena, which used to be challenging to address. However, in current CFD software, certain problems can be simulated using different approaches. In our article, we chose different rotating motion methods to analyze a counter-rotating dual-rotor wind turbine (CO-DRWT). Using the different rotating motion approaches we selected (mixing plane, frozen rotor, and sliding mesh), we examined the torque on the rotors and compared them. The following conclusion was reached. If transient fluid flow must be examined, then the sliding mesh method provided the most realistic results, while the frozen rotor method was adequate if we investigated the effect of wake and vortex near the rotating blades or on its environment. The mixing plane method should be used when the focus is on the kinetics and kinematics of the rotating blade or structure. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study was to evaluate the effect of runninginduced fatigue on the characteristic asymmetry of running gait and to identify non-linear differences in bilateral lower limbs and fatigued gait by building a machine learning model. Methods: Data on bilateral lower limb three-dimensional ground reaction forces were collected from 14 male amateur runners before and after a running-induced fatigue experiment. The symmetry function (SF) was used to assess the degree of symmetry of running gait. Statistical parameter mapping (Paired sample T-test) algorithm was used to examine bilateral lower limb differences and asymmetry changes pre- and post-fatigue of time series data. The support vector machine (SVM) algorithm was used to recognize the gait characteristics of both lower limbs before and after fatigue and to build the optimal algorithm model by setting different kernel functions. Results: The results showed that the ground reaction forces were asymmetrical (SF > 0.5) both pre-and post-fatigue and mainly concentrated in the medial-lateral direction. The asymmetry of the medial-lateral direction increased significantly after fatigue (p < 0.05). In addition, we concluded that the polynomial kernel function could make the SVM model the most accurate in classifying left and right gait features (accuracy of 85.3%, 82.4%, and 82.4% in medial-lateral, anteriorposterior and vertical directions, respectively). Gaussian radial basis kernel function was the optimal kernel function of the SVM algorithm model for fatigue gait recognition in the medial-lateral and vertical directions (accuracy of 54.2% and 62.5%, respectively). Moreover, polynomial was the optimal kernel function of the anterior-posterior direction (accuracy = 54.2%). Discussion: We proved in this study that the SVM algorithm model depicted good performance in identifying asymmetric and fatigue gaits. These findings can provide implications for running injury prevention, movement monitoring, and gait assessment. [ABSTRACT FROM AUTHOR]

Running-related limb asymmetries suggest specific sports injuries and recovery circumstances. It is debatable if running speed affected asymmetry, and more research is required to determine how longitudinal bending stiffness (LBS) affected asymmetry. The purpose of this study was to investigate the influence of running velocity and LBS on kinematic characteristics of the hip, knee, ankle, metatarsophalangeal joint (MTP) and the corresponding asymmetry. Kinematic (200 Hz) running stance phase data were collected bilaterally for 16 healthy male recreational runners (age: 23.13 ± 1.17, height: 175.2 ± 1.6 cm, body mass: 75.7 ± 3.6 kg, BMI: 24.7 ± 1.3 kg/m2) running on a force plate at three different velocities (10, 12 and 14 km/h) and three increasing-LBS shoes in a randomized order. The symmetry angle (SA) was calculated to quantify gait asymmetry magnitude at each running velocity and LBS. Changes in running velocity and LBS led to differences in kinematic variables between the hip, knee, ankle and MTP (p < 0.05). Significant changes in SA caused by running velocity were found in the knee flexion angle (p = 0.001) and flexion angle peak velocity (p < 0.001), ankle plantarflexion angle (p = 0.001) and plantarflexion angle peak velocity (p = 0.043) and MTP dorsiflexion angle (p = 0.001) and dorsiflexion angle peak velocity (p = 0.019). A significant change in the SA caused by LBS was found in the MTP dorsiflexion peak angle velocity (p = 0.014). There were interaction effects between running velocity and LBS on the MTP plantarflexion angle (p = 0.033) and plantarflexion angle peak velocity (p = 0.038). These findings indicate the existence of bilateral lower limb asymmetry. Meanwhile, it was proved that running velocity and LBS can influence the asymmetry of lower limb joints. Additionally, there was an interaction between running velocity and LBS on the asymmetry of the lower limb. These findings can provide some information for sports injuries, such as metatarsal stress fractures and anterior cruciate ligament injuries. They can also provide some useful information for running velocities and running shoes. [ABSTRACT FROM AUTHOR]

Beside prosthesis loosening, wear is the mechanical factor that most significantly influences the lifetime of total knee replacements (TKRs), which can only be described by a number of interrelated parameters. The examination of the wear occurring in TKRs is mostly carried out as a combination of experiments and mathematical modeling. The experiment can provide the real magnitude of wear, while the model is intended to mathematically describe the relationship between wear and the wear-inducing parameters. On the one hand, this study focuses on the mathematical description of wear as a natural-technical phenomenon, presenting the most important analytical and numerical models, while also providing an open view on exciting questions that still await answers. [ABSTRACT FROM AUTHOR]

Although various sports footwear demonstrated marked changes in running biomechanical variables, few studies have yielded definitive findings on the underlying mechanisms of shoe constructions affecting running-related performance and injuries. Therefore, this study focused on examining the effect of basic shoe constructions on running biomechanics and assessing the current state of sports shoe production in terms of injury and efficiency. Relevant literature was searched on five databases using Boolean logic operation and then screened by eligibility criteria. A total of 1260 related articles were retrieved in this review, and 41 articles that met the requirements were finally included, mainly covering the influence of midsole, longitudinal bending stiffness, heel-toe drop, shoe mass, heel flare, and heel stabilizer on running-related performance and injuries. The results of this review study were: (1) The functional positioning of running shoe design and the target groups tend to influence running performance and injury risk; (2) Thickness of 15–20 mm, hardness of Asker C50-C55 of the midsole, the design of the medial or lateral heel flares of 15°, the curved carbon plate, and the 3D printed heel cup may be beneficial to optimize performance and reduce running-related injuries; (3) The update of research and development concepts in sports biomechanics may further contribute to the development of running shoes; (4) Footwear design and optimization should also consider the influences of runners' strike patterns. [ABSTRACT FROM AUTHOR]

Introduction: Footwork is one of the training contents that table tennis players and coaches focus on. This study aimed to gain a thorough understanding of the muscle activity of the table tennis footwork and creating a musculoskeletal model to investigate the muscle forces, joint kinematic, and joint kinetic characteristics of the footwork during topspin forehand stroke. Methods: Six male table tennis athletes (height: 171.98 ± 4.97 cm; weight: 68.77 ± 7.86 kg; experience: 10.67 ± 1.86 years; age: 22.50 ± 1.64 years) performed chasse step and one-step footwork to return the ball from the coach by topspin forehand stroke. The kinematics, kinetics, and muscle activity of the lower limb were recorded by the motion capture, force platform, and Electromyography (EMG) system. Statistical parametric mapping (SPM) analysis was used to investigate any difference between the chasse step and one-step footwork during the stroke. Results and Conclusion: The muscle force of the biceps femoris long head (p < 0.001), lateral gastrocnemius (p < 0.001), vastus lateralis (p < 0.001), vastus medial (p < 0.001), rectus femoris (p < 0.001), and tibia anterior (p < 0.001) of the chasse step were significantly greater than the one-step footwork during the early stroke phase (stance). At the end of the stroke phase (push-off), the muscle force of the biceps femoris long head (p < 0.001), medial gastrocnemius (p < 0.001), lateral gastrocnemius (p < 0.001), rectus femoris (p < 0.001), and tibias anterior (p < 0.001) in the chasse step footwork was significantly greater than the one-step footwork. The muscle force of the ankle plantar flexor and valgus muscle groups in the one-step was significantly greater than in the chasse step. Besides, the moment and angle of hip flexion (p = 0.001) and axial rotation (p = 0.009) were significantly greater for the chasse step than the one-step footwork, as well as the ankle plantar-flexion angle (p < 0.001) and moment (p < 0.001) of the one-step footwork were significantly higher than the chasse step footwork. The results of this study can be applied to movement control and injury prevention in table tennis footwork. [ABSTRACT FROM AUTHOR]

This study investigates the symmetry change in joint angle and joint moment of knee joints following a Running-Induced Fatigue counter movement Jump. Twelve amateur runners volunteered to participate in the study. A prolonged running protocol was used to induce fatigue. Joint angle and moment were recorded during the push and flexion phase of the CMJ before and immediately after fatigue. Borg scale (RPE>17) and real-time heart rate monitoring (HR>90%HRmax) were used to confirm running fatigue. Symmetry function (SF) was used to assess the symmetry of the knee Angle and moment variation parameters over the entire push-off and landing phases based on time series analysis. Paired sample t-test was used to examine changes in SF before and after acute fatigue. The Angle and moment of the knee are asymmetrical in all planes (SF > 0.05), with SF ranging from 5 to 130% in angle and 5-110% in moment. There was a significant increase in knee joint angle asymmetry in the horizontal plane during the push-off and landing stage following the prolonged - Running Protocol implementation. These increases in asymmetry are mainly caused by excessive external rotation of the dominant knee joint. These findings indicate that fatigue-induced changes during CMJ may progress knee movement pattern asymmetry in the horizontal plane. [ABSTRACT FROM AUTHOR]

The aim of this study is to review the valuable lower limb biomechanical contribution to table tennis topspin forehand. Databases included Scopus, PubMed, and Web of science. In this case, 19 articles were selected for the systematic review. The mechanics of the plantar, lower limb joints kinematics and kinetics, muscle activity, and racket-joint relationship are described through gender, performance level, and footwork. The study found that the hip movement characteristics and the hip muscle group activity following a proximal-to-distal sequence strategy significantly contributed to the maximum acceleration of the racket. Optimizing the motion strategy of the ankle and plantar as well as the ankle muscle group activity is beneficial for the transmission of energy in the kinetic chain. Muscle groups around the ankle and subtalar joints are heavily activated during landing to maintain foot stability during the landing phase. Lower limb muscle development plays an important role in movement control and stability as well as sports injury prevention in table tennis footwork during the performance of the topspin forehand. Furthermore, physical development levels and anatomical differences (such as hip and lower trunk muscle strength differences), maybe the main reasons for gender differences observed during the topspin forehand. Systematically summarizing this valuable information can contribute to athletes' and coaches' knowledge to enhance topspin forehand performance and training regimes. We suggest that future research could consider the joint contact forces, ball movement, and ball-racket impact during a performance of topspin forehand. [ABSTRACT FROM AUTHOR]

Background: Amyotrophic lateral sclerosis (ALS) is a progressive neuromuscular disease whose primary hallmark is the progressive degeneration of motor neurons in the brainstem, spinal cord, and cerebral cortex that leads to weakness, spasticity, fatigue, skeletal muscle atrophy, paralysis, and even death. Exercise, as a non-pharmacological tool, may generally improve muscle strength, cardiovascular function, and quality of life. However, there are conflicting reports about the effect of exercise training in adults with ALS. Aims: This systematic review and network meta-analysis aim to conduct a mixed comparison of different exercise interventions for function, respiratory, fatigue, and quality of life in adults with ALS. Methods: Randomized controlled trials with ALS participants were screened and included fromthe databases of PubMed, Medline, andWeb of Science. Physical exercise interventions were reclassified into aerobic exercise, resistance training, passive exercise, expiratory muscle exercise, and standard rehabilitation. Patient-reported outcome measures would be reclassified from perspectives of function, respiratory, fatigue, and quality of life. The effect size would be transferred into the percentage change of the total score. Result: There were 10 studies included, with the agreement between authors reaching a kappa-value of 0.73. The network meta-analysis, which was conducted under the consistency model, identified that a combined program of aerobic exercise, resistance exercise, and standard rehabilitation showed the highest potential to improve quality of life (0.64 to be the best) and reduce the fatigue (0.39 to be the best) for ALS patients, while exercise program of aerobic and resistance training showed the highest potential (0.51 to be the best) to improve ALS patients' physical function. The effect of exercise on the respiratory was still unclear. Conclusion: A multi-modal exercise and rehabilitation program would be more beneficial to ALS patients. However, the safety and guide for practice remain unclear, and further high-quality randomized controlled trials (RCTs) with a larger sample are still needed. [ABSTRACT FROM AUTHOR]

Objective. The purpose of this research was to use a new method the human and bar combination barycenter to exposit the differences between successful and failed characteristics of snatch attempts in competition. Try to establish an effective biomechanical method that can uncover the main factors for the failed snatch. The obtained results will provide valuable information for weightlifters to improve the success rate in snatch by altering their technical issues accordingly. Methods. A 3-D video analysis method was used to compare the characteristics of the heaviest successful and failed attempts of ten elite weightlifters in the men's 73 kg category. The video was captured under competitive conditions at the 2019 World Weightlifting Championships, the 2019 Asian Weightlifting Championships, and the 2020 China Olympic Trial. The video data were digitized using the SIMI°Motion7.50 3-D system (Germany). Results. Significant difference (P > 0.05) was not found between the successful and failed attempts in the parameters, such as the maximal vertical rising velocity, the maximal vertical height, and the vertical displacement of the barbell. The maximal descending acceleration of the human body, the time duration, the angles of the hip, and knee joints were no significant difference. However, significant differences were found in the variation of the human and bar combination barycenter on the X -axis in the inertial ascent stage and the squat support stage (t = 2.862 , P < 0.05 ; t = 3.376 , P < 0.05). Conclusions. A probable cause of the failed snatch is that the displacement of human and bar combination barycenter on the X -axis is not enough to reach the position for supporting barbell during the inertial ascent stage and the squat support stage. The reason is that the strength of reclining of torso at the end of the force phase is insufficient. Insufficient knee flexion in the knee flexion phase (M 2), which leads to a lower maximum vertical velocity of barbell, may be an indirect factor leading to the failed snatch. The cumulative variation of human and bar combination barycenter on the X -axis can effectively determine the technical characteristics between the success and failure in snatch. [ABSTRACT FROM AUTHOR]

Background: The dynamic balance between oxidation and anti-oxidation in the body's internal environment has a significant meaning for human health. Physical exercise and antioxidative supplementation could affect the balance of oxidation and anti-oxidation systems. The evidence on the effects of physical exercise and antioxidative supplementation is mixed. Aims: To identify the effects of physical exercise, antioxidative supplementation, and their combination on the dynamic balance between oxidation and anti-oxidation in different subgroups of healthy adults. Methods: All studies which reported randomized controlled trials with healthy participants were screened and included from the databases of PubMed, Medline, Embase, and Ovid. All participants were reclassified according to their different daily life activities. All physical exercise interventions were reclassified according to the intensity. The effect size would be calculated in percent or factor units from the mean level change with its associated random-effect variance. Result: There were 27 studies included in this review. The agreement between authors by using The Cochrane Collaboration Risk of Bias Assessment Tool reached a kappa-value of 0.72. Maintaining a regular physical exercise routine in an appropriate intensity would be beneficial to the body's anti-oxidative potential. Anti-oxidative supplementation could have some positive but limited effects on the body's anti-oxidative status and complex interaction with physical exercise. Conclusion: Keeping a regular physical exercise routine and gradually increasing its intensity according to the individual's daily life activity might be a better choice to maintain and enhancing the body's antioxidation potential, only using anti-oxidative supplementation is not recommended. More research is needed to explore the best combination protocol. Registration Number: CRD42021241995. [ABSTRACT FROM AUTHOR]

The growing need for sustainable technologies has attracted considerable interest in the synthesis of ecofriendly materials. This paper reports the anti-inflammatory and antibacterial activities of sustainable silver nanoparticles (AgNPs) fabricated using endophytic fungus extracted from a medicinal plant, Cassia fistula. Fourier transform-infrared and UV-visible were used for AgNPs characterisation. X-ray diffraction, scanning electron microscope, energy dispersive X-ray analysis, atomic force microscope (AFM), transmission electron microscope and dynamic light scattering analysis revealed that the biosynthesised AgNPs were within the size of ~4–54 nm. The synthesised AgNPs displayed considerable antibacterial activity against Staphylococcus aureus, Escherichia coli and Klebsiella pneumonia bacterial strains. Additionally, synthesised AgNPs showed significant anti-inflammatory potential. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVE: The aim of this study was to explore the effectiveness of arch support functional insoles to prevent metatarsalgia. METHOD: Twenty-five healthy females participated in the study. A Vicon motion capture system was used to collect kinematics data of the lower limb. An AMTI force plate was used to record the vertical ground reaction force (GRF), and the Novel Pedar-X System was used to measure foot pressure while subjects wore normal insoles or functional insoles with an arch support during walking and jogging. RESULTS: With the arch support functional insoles, the first metatarsal (FM) region's contact area was increased and the peak pressure and time-pressure integral of the FM and second and third metatarsal (SATM) were areas decreased. This suggests a lower risk of longitude stress injuries in these areas. The ankle dorsiflexion angle of jogging with the 'arch support functional insoles' (RF) and walking with the 'arch support functional insoles' (WF) were significantly increased at initial contact and the knee and hip flexion angle of RF and WF were reduced. The peak hip extension angle of WF and RF also declined. The vertical loading rate of RF was lower, which would be beneficial in reducing the risk of lower limb injuries during jogging. CONCLUSIONS: The results demonstrate that arch support functional insoles can be used effectively to prevent and decrease pain and promote a suitable weight-bearing pattern in the foot for promoting the health of young females. [ABSTRACT FROM AUTHOR]

Patellar tendinopathy is a clinical symptom of patellar tendons characterized by local pain in the front of the knee joint. It is common among basketball and volleyball players. Patients with patellar tendinopathy may exhibit different landing strategies during landing compared to healthy individuals. The purpose of this study was to compare the differences in lower limb joint energy dissipation (eccentric work) values for the symptomatic patellar tendinopathy (PT) athletes and no patellar tendinopathy (UPT) athletes during single-leg landing. A total of 26 (PT: 13, UPT:13) semi-professional male basketball and volleyball player's kinetic data were collected during the landing phases. Joint work was calculated by the integral of joint power over time. In this study, the result showed that the ankle joint means energy dissipation (p < 0.001) and total energy dissipation (p < 0.001) of PT were significantly greater than UPT. Compared to the UPT athletes, the PT athletes showed smaller knee joint mean energy dissipation (p = 0.002) and contribution to total energy dissipation (p < 0.001) during the landing stance. Meanwhile, there were no differences in hip joint contribution to total energy dissipation (p = 0.523) and lower limb total energy dissipation (p = 0.127). A deeper understanding of each joint's energy dissipation contribution ratio between UPT and PT during landing can provide clues that reveal the biomechanical mechanism of PT athletes landing. Further study should choose a larger sample size to more comprehensively reveal the energy dissipation strategy of PT during landing. [ABSTRACT FROM AUTHOR]

Background: Running-induced fatigue has received much attention in recent years. However, very few studies have investigated the effect of fatigue on lower limb biomechanics in three planes.Objective: This study was designed to investigate biomechanical changes in the lower limb in three planes following running-induced fatigue.Methods: Fifteen male novice runners were included in the study and performed three running trails pre- and post-fatigue. Wilcoxon signed-rank tests or paired-sample t tests were used to analyze the data.Results: Lower limb biomechanics significantly changed, especially kinetic parameters, when fatigue occurred. The peak ankle dorsiflexion angle and range of motion of the knee joint in the frontal plane increased. As for kinetic parameters, in the ankle joint, the peak external rotation moment, peak abduction power and peak internal rotation power increased. In the knee joint, the peak abduction and external rotation moment, peak flexion power, peak adduction and abduction power also increased. In the hip joint, the peak flexion moment was decreased, peak adduction and abduction moment, peak external rotation power, peak adduction and abduction power moment were increased.Conclusion: The findings of this study may contribute to our understanding of the impact of fatigue and provide some helpful information to prevent related injuries. [ABSTRACT FROM AUTHOR]

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Purpose. Examining and understanding the biomechanics of novice runners and experienced runners can further improve our knowledge within the field of running mechanics and running injuries. The purpose of this study was to classify the differences in lower limb biomechanics during a 3.3 m/s running task among both experienced runners and novice runners. Method. Twenty-four participants (12 experienced runners and 12 novice runners) ran at 3.3 m/s across a force plate; kinematics and kinetics data were collected by the Vicon motion system and Kistler force plate. Group comparisons were made using an independent samples t -test to identify differences in the impact peak, loading rate, contact time, ankle, knee, and hip joint kinematics and kinetics during the stance phase. Results. No significant differences were observed between novice and experienced runners for both ankle and knee joint kinetics except that the ankle joint plantar flexion torque was significantly greater in the novice runners. However, the plantar flexion, dorsiflexion, range of motion (ROM), plantar flexion torque, and max angular velocity of ankle joint significantly increased in novice runners than inexperienced runners. Additionally, the flexion angle and range of motion of the hip joint were observed to be larger in the novice runners. Moreover, the maximum extension torque and the maximum extension power in the hip joint were significantly increased in the experienced runners. There were no significant differences in the first peak, contact time, and average vertical loading rate. Novice runners showed a larger vertical instantaneous loading rate than experienced runners. Conclusion. These preliminary findings indicate that novice runners are prone to running injuries in comparison to experienced runners. Novice runners showed larger kinematics and kinetic parameters in the joint of the ankle and hip. Novice runners should enhance muscle strength in the hip and choose scientific training methods. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the influence of cryotherapy on the balance ability after lower extremity muscle fatigue. Twelve table tennis players were selected in this research. The static and dynamic balance abilities of the participants at six different moments were collected by a 1000 HZ Kistler force platform and Y balance test system. SPSS19.0 software was used to analyze the results of experimental indicators by selecting two-factor repeated measurement ANOVA. 1) From the moment of 24 h post intervention, the effect of cryotherapy on dynamic balance recovery was significantly better than no cryotherapy. 2) Except for the COP (Center of Pressure) maximum displacement on ML (Medium-Lateral axis) at the moment of 72 h post intervention, the cryotherapy had no positive effect on the recovery of static balance ability. 3) Cryotherapy has a significant negative impact on the COP maximum displacement in ML and AP (Antero-Posterior axis) at the moment of post cryotherapy, which may lead to the decline of static balance ability. It was not recommended to use cryotherapy for balance recovery if the competition was on the same day or within 24 h. However, the cryotherapy was recommended to use if the competition was in the next day or after the next day. [ABSTRACT FROM AUTHOR]

The coronavirus 2019 (COVID-19) pandemic has posed a significant threat to human health around the world. A severe risk of infection has been observed in elderly populations. In addition, individuals with obesity and obesity-related comorbidities have also been identified to be at a higher risk of infection for COVID-19. We have attempted here to provide evidence in support of exercise management as a prevention strategy for improving health and minimizing the effects of COVID-19. Therefore, exercise duration, frequency, and intensity benefits are summarized in an attempt to provide guidelines for the general population. In terms of exercise effects, there are multiple benefits of exercise related to human health. These include, decreases in adipose tissue, improvements in cardio-respiratory fitness, enhanced metabolic homeostasis, and suppress inflammation active. With respect to the amount of exercise performed individuals should exercise at a moderate intensity for at least 150 min/wk as an initial target. Increases in intensity and duration of exercise training are necessary for significant fitness benefits, weight loss, and prevention of weight regain. In relation to walking, 10,000 steps/day at a rate of 64–170 steps/minute for at least 10 min duration is reasonable for healthy adults. For exercise intensity, a combination of resistance training (RT), aerobic training (AT) as well as high-intensity interval training (HIIT) incorporated with moderate-intensity continuous training (MICT) can be recognized as an optimal exercise mode for health benefits. Aerobic training and MICT should be viewed as a basis for exercise in combination with appropriate volumes and types of RT and HIIT. Activities should be performed according to professional guidelines and advice. If implemented, these measures may reduce infection rates, underlying pathologies, and assist in decreasing mortality associated with COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Backward walking (BW) has been extensively used in athletic training and orthopedic rehabilitation as it may have value for enhancing balance. This study identified the differences in foot intersegment kinematics (forward walking (FW) vs. time-reversed BW) and plantar pressure parameters of 16 healthy habitually shod individuals walking FW and BW using flexible shoes (SH) and under barefoot conditions (BF). BW was found to have shorter stride length (SL) and higher stride frequency (SF) under BF conditions compared with SH, which indicates a better BW gait stability under BF conditions. Decreased HX/FF dorsiflexion at HO in BW induces less plantar aponeurosis tension which may inhibit the windlass mechanism compared to FW walking. Increased forefoot relative to hindfoot (FF/HF) pronation and sequentially hindfoot relative to tibia (HF/TB) eversion combined with medially distributed plantar pressure and a higher plantar contact area in the medial side in BW-BF maybe beneficial in maintaining balance. These results indicate that BW training may be more reliable under BF conditions compared to the SH conditions based on greater sensory information feedback from the plantar area resulting in better biomechanical behavior. [ABSTRACT FROM AUTHOR]