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The quadricep muscles are commonly targeted for electrical muscle stimulation (EMS), while the gastrocnemius muscles, despite their crucial role in push-off, are often overlooked. The purpose was to investigate whether incorporating EMS into gastrocnemius training could optimize athletic performance. Two groups of athletes received regular gastrocnemius training (Training-only) or combined EMS into training (Training + EMS) over four weeks. The sprint time, jump height, take-off ground reaction forces, ankle and knee joint power, and electromyography were assessed before and after the training sessions. Two-way ANOVA with repeated measures was performed to determine any significant effect. Both training-only and training + EMS groups showed increased jump height and faster sprint time after training (P < 0. 0 0 1). The participants in the two groups also generated higher take-off force and larger ankle and knee powers after training (P < 0. 0 0 1). EMS adds no significant improvement in performance outcomes (P > 0. 0 5). This study implicates that both training-only and training + EMS can enhance sports performance and take-off force and lower-limb joint powers of the athletes, but the use of EMS can only induce minimal added improvements on gastrocnemius training. [ABSTRACT FROM AUTHOR]

Astronauts are exposed to microgravity-induced health problems in spaceflight missions. Countermeasures and physical exercises have received increasing attention and its current research trends and landscapes warranted investigation. We conducted a comprehensive bibliometric analysis on astronaut training/countermeasures using the available data from the Web of Science Core Collection database from 1992 to 2022 to summarize the research trends and identify future directions. A total of 1,520 relevant articles were identified. Annual publications of the field have been increased over the years with the emergence of new and effective countermeasures. ‘Microgravity’ was the centered hotspot surrounded by the topics included ‘spaceflight’, ‘hind leg hanging’, ‘simulated microgravity’, and ‘simulated weightlessness’. The top countries that produced the most publications included United States (726 articles), Germany (129 articles), and France (84 articles). The United States played a dominant role in the collaboration network with other countries. Meanwhile, NASA from the United States led the global collaborations and dominated the literature. Future research trend might lie on the design of physical training exercises to tackle the potential health problems on osteoporosis, muscle atrophy, and abnormality on the nervous and cardiovascular system; and artificial/simulated gravity with interdisciplinary sports countermeasure research on physiology, brain science, biomechanics, and aerospace medicine. [ABSTRACT FROM AUTHOR]

This study examines the effects of limb dominance and lead limb in task initiation on the kinetics and kinematics of step-off drop landings. Nineteen male participants performed drop landings led by the dominant and non-dominant limbs at 45-cm and 60-cm drop heights. Ground reaction force (GRF) and lower body kinematic data were collected. Between-limb time differences at the initial ground contact were calculated to indicate temporal asymmetry. Statistical Parametric Mapping (SPM) was applied for waveform analysis while two-way repeated measures ANOVA was used for discrete parameters. SPM results revealed greater GRF and lesser ankle dorsiflexion in the lead limb compared to the trail limb in 3 out of 4 landing conditions. The dominant limb displayed a greater forefoot loading rate (45 cm: p=.009, ηp2 = 0.438; 60 cm: p=.035, ηp2 = 0.225) and greater ankle joint quasi-stiffness (45 cm: p <.001, ηp2 = 0.360; 60 cm: p <.001, ηp2 = 0.597) than the non-dominant limb. Not all 380 trials were lead-limb first landings, with a smaller between-limb time difference (p=.009, d = 0.60) at 60 cm (4.1 ± 2.3 ms) than 45 cm (5.6 ± 2.7 ms). In conclusion, the step-off drop landing is not an ideal protocol for examining bilateral asymmetry in lower limb biomechanics due to potential biases introduced by limb dominance and the step-off limb. [ABSTRACT FROM AUTHOR]

This study examined the inter-day reliability and repeatability of change-of-direction (COD) performance to determine the minimum number of measurement trials required to represent a stable athlete's performance. Twenty-three university basketball players performed seven COD trials. Identical tests were performed two weeks later to evaluate inter-day reliability. Intra-class correlation coefficients were utilised to examine inter-day reliability for all data input methods. Separated ANOVA with repeated measures was performed to examine the trial effect. The ICC analysis indicated that data from the first trial exhibited the lowest reliability and that the fastest trial generally had higher reliability than the mean performance trial. The trial effect results revealed slower COD performance time in the first three trials than in later trials (p < 0.05), with no significant differences amongst later trials. These results suggested that at least four change-of-direction trials are required with respect to improving measurement reliability.

This systematic review investigated the effects of orthopedic, vibrating, and textured insoles on the postural balance of community-dwelling older adults. Articles published in English from 1999 to 2019 investigating the effects of (a) orthopedic, (b) vibrating, and (c) textured insoles on static and dynamic balance in community-dwelling older adults were considered. Twenty-four trials with a total of 634 older adults were identified. The information gathered generally supported the balance-improving effects of orthopedic, vibrating, and textured insoles in both static and dynamic conditions among community-dwelling older adults. Further examination found that rigidity, texture patterns, vibration thresholds, and components like arch supports and heel cups are important factors in determining whether insoles can improve balance. This review highlights the potential of insoles for improving the static and dynamic balance of community-dwelling older adults. Good knowledge in insole designs and an understanding of medical conditions of older adults are required when attempts are made to improve postural balance using insoles. [ABSTRACT FROM AUTHOR]

Biomechanical studies play an important role in understanding the pathophysiology of sleep disorders and providing insights to maintain sleep health. Computational methods facilitate a versatile platform to analyze various biomechanical factors in silico, which would otherwise be difficult through in vivo experiments. The objective of this review is to examine and map the applications of computational biomechanics to sleep-related research topics, including sleep medicine and sleep ergonomics. A systematic search was conducted on PubMed, Scopus, and Web of Science. Research gaps were identified through data synthesis on variants, outcomes, and highlighted features, as well as evidence maps on basic modeling considerations and modeling components of the eligible studies. Twenty-seven studies (n = 27) were categorized into sleep ergonomics (n = 2 on pillow; n = 3 on mattress), sleep-related breathing disorders (n = 19 on obstructive sleep apnea), and sleep-related movement disorders (n = 3 on sleep bruxism). The effects of pillow height and mattress stiffness on spinal curvature were explored. Stress on the temporomandibular joint, and therefore its disorder, was the primary focus of investigations on sleep bruxism. Using finite element morphometry and fluid–structure interaction, studies on obstructive sleep apnea investigated the effects of anatomical variations, muscle activation of the tongue and soft palate, and gravitational direction on the collapse and blockade of the upper airway, in addition to the airflow pressure distribution. Model validation has been one of the greatest hurdles, while single-subject design and surrogate techniques have led to concerns about external validity. Future research might endeavor to reconstruct patient-specific models with patient-specific loading profiles in a larger cohort. Studies on sleep ergonomics research may pave the way for determining ideal spine curvature, in addition to simulating side-lying sleep postures. Sleep bruxism studies may analyze the accumulated dental damage and wear. Research on OSA treatments using computational approaches warrants further investigation. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of varying midsole hardness on center of pressure (COP) and perceived stability during basketball-specific tasks, as well as the correlation between COP and perception measurements. A total of 20 male basketball players performed 45° cutting and layup while wearing basketball shoes with soft and hard midsoles. COP trajectories were obtained from the Pedar insole system. Stability perceptions at the forefoot and rearfoot were assessed using 150-mm visual analogue scales. Results indicated greater COP mediolateral deviations in soft midsole compared with hard midsole during layup (soft: 16.6 [4.7] mm, hard: 15.8 [4.6] mm, P =.03) but not 45° cutting (soft: 15.7 [5.9] mm, hard: 15.8 [5.6] mm, P =.60). While 16 out of 20 participants preferred soft midsole, no significant difference in visual analogue scale ratings was found between shoes for both tested movements. There was no significant correlation between COP and perceived stability during layup or 45° cutting. In conclusion, midsole hardness of basketball shoes did not consistently affect mediolateral stability of the foot during 45° cutting and layup. Subjective perception alone cannot be used to indicate mediolateral deviation of the foot when executing basketball-specific maneuvers. [ABSTRACT FROM AUTHOR]

Joint contact force is the actual force applied on the articular surface that could predict performance and injuries, but rarely reported for badminton sport. The study sought to calculate lower limb joint contact force and decelerative kinematics for badminton forward lunges. Fifteen badminton players performed backhand and forehand forward lunges in random order. The kinematic and kinetic data were input to scale a musculoskeletal model and solve inverse dynamics in the simulations. Outcome variables were compared between lunge conditions using repeated measures MANOVA. Forehand lunge produced higher compressional ankle contact force (p = 0.040, partial η2 = 0.14), faster touchdown hip abduction (p = 0.031, partial η2 = 0.16), and larger horizontal deceleration of the mass centre (p = 0.016, partial η2 = 0.19) and torso (p = 0.031, partial η2 = 0.16) compared to backhand lunge. Despite the statistical significance, we found that the increments of joint loading in forehand lunge were small (<5%) with limited effect size and could be attributed to the larger movement deceleration during braking. These force changes could possess performance merits. However, its linkage to injury risk is unclear and warrants further investigation. [ABSTRACT FROM AUTHOR]

Simple Summary: Different movement speeds can contribute to different joint loading in sports. Joint contact force is the actual force acting on the articular surface, which could predict performance and injury, but is rarely reported for badminton overhead strokes. From the perspective of sports biomechanics, this paper analyzes the characteristics of kinematics and mechanics at each stage of the fast and moderately paced movements and studies the changes in the force of the lower extremity joints caused by the characteristics of the movements at different speeds so that athletes and enthusiasts can clarify the essentials of the movements and prevent sports injuries. Different movement speeds can contribute to different joint loading in sports. Joint contact force is the actual force acting on the articular surface, which could predict performance and injury, but is rarely reported for badminton overhead strokes. Through an approach using musculoskeletal modelling, six male elite badminton players performed forehand overhead strokes at different movement speeds (fast (100%) vs. moderate (90%)). The synchronized kinematics and ground reaction force (GRF) data were measured using a motion capturing system and a force platform. All kinematics and GRF information were input into the AnyBody musculoskeletal modelling to determine the three-dimensional hip, knee and ankle contact forces. Paired t-tests were performed to assess the significant differences among the GRF, joint kinematics and contact force variables between the movement speed conditions. The results showed that when compared with the moderate movement condition, participants performing faster stroke movements induced larger first and second vertical peaks and larger first horizontal peak but lower second horizontal peak, and it also led to higher peak ankle lateral and distal contact forces, knee lateral and distal contact forces, and hip distal contact forces. Additionally, fast movements corresponded with distinct joint angles and velocities at the instant of initial contact, peak and take-off among the hip, knee and ankle joints compared with moderate movement speeds. The current results suggest that changes in joint kinematics and loading could contribute to changes in movement speeds. However, the relationship between lower limb joint kinematics and contact forces during overhead stroke is unclear and requires further investigation. [ABSTRACT FROM AUTHOR]

We investigated how midfoot stiffness of running shoes influences foot segment kinematics and ground reaction force (GRF) during heel-toe running. Nineteen male rearfoot strike runners performed overground heel-toe running at 3.3 m/s when wearing shoes with different midfoot bending stiffnesses (low, medium, and high) in a randomized order. A synchronized motion capture system (200 Hz) and force plate (1000 Hz) were used to collect the foot-marker trajectories and GRF data. Foot kinematics, including rearfoot-lab, midfoot-rearfoot, forefoot-rearfoot, and forefoot-midfoot interactions, and kinetics, including GRF characteristics, were analyzed. Our results indicated that high midfoot stiffness shoes reduced the forefoot-rearfoot range of motion (mean ± SD; high stiffness, 7.8 ± 2.0°, low stiffness, 8.7 ± 2.1°; p < 0.05) and forefoot-midfoot range of motion (mean ± SD; high stiffness, 4.2 ± 1.1°, medium stiffness, 4.6 ± 0.9°; p < 0.05) in the frontal plane. No differences were found in the GRF characteristics among the shoe conditions. These findings suggest that an increase in midsole stiffness only in the midfoot region can reduce intersegmental foot medial-lateral movements during the stance phase of running. This may further decrease the tension of the foot muscles and tendons during prolonged exercises. [ABSTRACT FROM AUTHOR]

This study examined the effects of shoes' segmented forefoot stiffness on athletic performance and ankle and metatarsophalangeal joint kinematics and kinetics in basketball movements. Seventeen university basketball players performed running vertical jumps and 5-m sprints at maximum effort with 3 basketball shoes of various forefoot plate conditions (medial plate, medial + lateral plates, and no-plate control). One-way repeated measures ANOVAs were used to examine the differences in athletic performance, joint kinematics, and joint kinetics among the 3 footwear conditions (α = .05). Results indicated that participants wearing medial + lateral plates shoes demonstrated 2.9% higher jump height than those wearing control shoes (P = .02), but there was no significant differences between medial plate and control shoes (P > .05). Medial plate shoes produced greater maximum plantar flexion velocity than the medial + lateral plates shoes (P < .05) during sprinting. There were no significant differences in sprint time. These findings implied that inserting plates spanning both the medial and lateral aspects of the forefoot could enhance jumping, but not sprinting performances. The use of a medial plate alone, although induced greater plantar flexion velocity at the metatarsophalangeal joint during sprinting, was not effective in improving jump heights or sprint times. [ABSTRACT FROM AUTHOR]

Runners' gait patterns vary during a half marathon and influence the knee joint mechanics. Joint contact force is a better estimate of the net joint loadings than external joint moments and closely correlates to injury risks. This study explored the changes of lower limb joint kinematics, muscle activities, and knee joint loading in runners across the running mileages of a half marathon. Fourteen runners completed a half marathon on an instrumented treadmill where motion capture was conducted every 2 km (from 2 to 20 km). A musculoskeletal model incorporating medial/lateral tibiofemoral compartments was used to process the movement data and report outcome variables at the selected distance checkpoints. Statistics showed no changes in joint angles, muscle co-contraction index, ground reaction force variables, and medial tibiofemoral contact force (p > 0.05). Knee adduction moment at 18 km was significantly lower than those at 2 km (p = 0.002, γ = 0.813) and 6 km (p = 0.001, γ = 0.663). Compared to that at 2 km, lateral tibiofemoral contact force was reduced at 18 km (p = 0.030, Hedges' g = 0.690), 16 km (p < 0.001, Hedges' g = 0.782), 14 km (p = 0.045, Hedges' g = 0.859), and 10 km (p < 0.001, Hedges' g = 0.771) respectively. Mechanical realignment of the lower limb may be the cause of the altered knee loadings and possibly led to reduced running economy in response to a prolonged run. The injury potential of the redistributed tibiofemoral forces warranted further studies. [ABSTRACT FROM AUTHOR]

Objective. This study examined the influence of shoe bending stiffness on lower extremity energetics in the take-off phase of consecutive jump. Methods. Fifteen basketball and volleyball players wearing control shoes and stiff shoes performed consecutive jumps. Joint angle, angular velocity, moments, power, jump height, take-off velocity, take-off time, and peak vertical ground reaction force data were simultaneously captured by motion capture system and force platform. Paired t -tests were performed on data for the two shoe conditions that fit the normal distribution assumptions, otherwise Wilcoxon signed-rank tests. Results. There are significant differences (P < 0.05) in take-off velocity and take-off time between stiff and control shoe conditions; the stiff shoes had faster take-off velocity and shorter take-off time than control shoes. There was no significant difference between two conditions in jump height (P = 0.512) and peak vertical ground reaction force (P = 0.589). The stiff shoes had significantly lower MTP dorsiflexion angle and greater joint work than the control shoes (P < 0.05). The MTP range of motion and maximum angular velocity in stiff shoe condition were significantly lower than those in control shoe condition (P < 0.01). However, there are no significant differences between two conditions in kinetics and kinematics of the ankle, knee, and hip joint. Conclusions. The findings suggest that wearing stiff shoes can reduce the effect of participation of the MTP joint at work and optimize the energy structure of lower-limb movement during consecutive jumps. [ABSTRACT FROM AUTHOR]

Simple Summary: Currently, there are various shoe lateral upper support designs (forefoot, rearfoot, forefoot-to-rearfoot) available in the market, but scientific guidelines are not well established. This study examined the location effect of lateral shoe upper supports on the ground reaction forces, as well as ankle kinematics and moments during the change of direction maneuvers using a statistical parametric mapping approach. The forefoot support shoe had a reduced eversion moment in between ~25–95% across all change of directions. The forefoot upper support shoe had increased ankle inversion between ~8–14% (complete turns) and ~96–100% of contact time (side-cuts and lateral shuffles), and increased inversion velocity in side-cuts. The rearfoot upper support shoes reduced inversion velocity in lateral shuffle compared to no support. These findings suggest that lateral upper support location on basketball shoes can influence coronal plane ankle mechanics, but not ground reaction forces. This study examined the location effect of lateral shoe upper supports on the ground reaction forces, as well as ankle kinematics and moments during the change of direction maneuvers using a statistical parametric mapping approach. University basketball athletes performed side-cuts, complete turns and lateral shuffle maneuvers with their maximum-effort in four shoe conditions with varying shoe upper support locations: full-length, forefoot, rearfoot, none (control). The statistical parametric mapping repeated measures ANOVA test was applied to compare differences between the shoe conditions, followed-up with post-hoc statistical parametric mapping paired t-tests between all shoe conditions. The coronal ankle results revealed that the forefoot support shoe had a reduced eversion moment that varied between ~25–95% across all change of directions (p < 0.05). However, the forefoot upper shoe had increased ankle inversion between ~8–14% (complete turns) and ~96–100% (side-cuts and lateral shuffles), and increased inversion velocity in side-cuts than the other shoes (p < 0.05). Compared to the control, the rearfoot support shoes reduced inversion velocity in side-cut between ~78–92% (p < 0.05). These findings suggest that a forefoot upper support induced most changes in ankle mechanics during basketball cutting maneuvers, with only inversion angle in the complete turn being influenced during the initial period where ankle injury may occur. Future research should examine if these coronal ankle mechanics influence change-of-direction performance and injury risk with regular wear. [ABSTRACT FROM AUTHOR]

Simple Summary: Professional mobile esports athletes may suffer from occupational health risks to their spine because of prolonged sitting with poor posture. The aim of this study is to examine whether esports athletes have poor spine posture, mobility, and stability. Our results showed that professional mobile esports athletes had significantly poorer spine posture, and weaker spine mobility and stability than non-athletes. They may be more susceptible than non-athletes to spine-related musculoskeletal problems, such as back pain or neck pain. Physical-training programs and other ergonomic considerations should be sought to mitigate the risk of musculoskeletal problems and potential injuries for the athletes. Professional esports athletes spend a long time in the same sitting posture during training and competition. Mobile esports may exacerbate potential postural problems because of the closer and unsupported arms and because athletes spend more time in a forward-/flexed-head posture. Prolonged sitting in these postures carries significant health risks and may lead to musculoskeletal problems and injuries. The objective of this retrospective study is to assess the posture, mobility, and stability of the spine for professional mobile esports athletes. We collected spine-assessment data from 48 athletes participating in a top-tier league on a real-time-strategy battle-arena online game. The spinal assessment was conducted using the SpinalMouse® under upright standing and trunk flexion in addition to the Matthiass test. Measurements were converted into Idiag Scores by the SpinalMouse® software. The Idiag Posture, Idiag Mobility, and Idiag Stability scores were 62.50 (IQR: 21), 63.50 (IQR: 19.5), and 54.50 (IQR: 14.5), respectively, and were significantly lower (p < 0.001) than the reference normative value (100). Age was found to have a weak positive correlation with the posture score (ρ = 0.29, p = 0.048). Although career duration appeared to lower the scores, the association was insignificant (p > 0.05). The scores also had no significant association with body height, body mass, body mass index, and esports team (p > 0.05). It was anticipated that mobile-based esports would attenuate the biomechanics of the spine and increase the likelihood of musculoskeletal problems, such as neck and back pain. [ABSTRACT FROM AUTHOR]

Background: Electromyographic systems are widely used in scientific and clinical practice. The reproducibility and reliability of these measures are crucial when conducting scientific research and collecting experimental data.Objective: To test the reliability of surface electromyography signals from both the Flexor Digitorum Superficialis (FDS) and Extensor Carpi Radialis Brevis (ECRB) muscles of both the left and right arms during an individual, static multi-planar maximum voluntary contraction handgrip task using the Myon 320 system (Myon AG, Switzerland).Methods: Eight right-handed male participants performed two maximal handgrip tests in five separate wrist positions using both hands. Muscle activity was recorded from both forearms. Reliability was measured using the Standard Error of Measurement (SEM), Coefficient of Variation (CV) and Intra-class correlation coefficients. Wrist joint position correlations within and between the FDS and ECRB muscle activities were also analysed.Results: Absolute reliability was shown across all positions for both hands with CV and SEM recorded at below 10%. The output measures indicate that the Myon 320 system (Myon AG, Switzerland) produces good to fair reliability when assessing forearm muscle activity. Correlations in the left FDS muscles were negative. Correlations between the left ECRB and left FDS muscles were variable but positive between the right ECRB and right FDS muscles.Conclusions: The data sets retrieved from all participants were reliably evaluated. Wrist position correlations within and between the FDS and ECRB muscles may have been influenced by hand dominance. The findings demonstrate that the methods and systems outlined in this study can be used reliably in future research. [ABSTRACT FROM AUTHOR]

Forefoot and toes are prominent regions for locomotion and individual metatarsophalangeal joint (MTPJ) stiffness may be linked to jump take-off mechanics and performances. However, little is known about the relationships between MTPJ stiffness and take-off related variables. This study examined the relationship between individual MTPJ stiffness and biomechanical variables under various vertical countermovement jumps (CMJ) conditions. We measured MTPJ stiffness on 21 male university basketball players and then asked them to perform jumps under single, consecutive and running CMJ conditions. Pearson's correlation coefficient was employed to examine the relationships between MTP passive stiffness and each jumping performance, ground reaction force (GRF) and joint kinematic and kinetic variables. The results indicated that MTPJ stiffness significantly correlated with maximum jump height (r = 0.49, moderate), peak take-off velocity (r = 0.47, moderate), peak take-off ankle plantarflexion moment (r = 0.68, strong), peak dorsiflexion moment (r = 0.60, strong) and peak take-off ankle power (r = 0.44, moderate) in consecutive CMJ. Only a moderate correlation between MTPJ stiffness and peak MTPJ extension take-off velocity (r = −0.46, moderate) was determined in a single CMJ. There were no significant correlations found in running CMJ conditions. These findings imply that higher MTPJ stiffness of participants was related to improved jump performances in consecutive jumps. [ABSTRACT FROM AUTHOR]

This study examined the effects of shoe collar height and foot orthosis on ground reaction force (GRF), ankle and knee mechanics during landing. Sixteen male university basketball players performed drop landing when wearing different shoes with collar height (high vs. low) and foot orthoses (arch-support vs. flat). Biomechanical variables included vertical peak GRF and joint angles and moments in sagittal and coronal planes were analysed with two-way ANOVA with repeated measures (α = 0.05). Results indicated that high-collar shoes had significantly smaller peak ankle dorsiflexion (P < 0.001), smaller ankle sagittal total RoM (P < 0.001), higher forefoot peak GRF (P = 0.009) and peak knee valgus moment (P < 0.001) compared with low-collar shoes. Wearing arch-support orthoses induced higher forefoot peak GRF (P < 0.001) but smaller ankle inversion moment (P = 0.001) compared to flat-orthoses. Furthermore, significant interactions between collar-height and orthosis were found only for initial ankle plantarflexion (P = 0.023) and knee flexion (P = 0.035), but not in any kinetics variables. The findings suggest increased collar height and arch-support orthoses appear to reduce the risks of ankle sprains during landing, but might increase loading at adjacent joints. [ABSTRACT FROM AUTHOR]

Simple Summary: Tai-Chi is a popular indoor-based exercise that could induce several health-related benefits, but its benefits for middle-aged adults are unclear. Tai-Chi exercise can equally improve cardiorespiratory fitness, resting health rate, blood pressure and lean mass as a moderate-intensity running exercise. Running exercises appears to have further benefits in reducing the blood lipid level. The results from this study can provide insights into various types of exercises on cardiorespiratory fitness and biomarkers in the middle-aged population. This study examined the effectiveness of Tai-Chi and running exercises on cardiorespiratory fitness and biomarkers in sedentary middle-aged adults under 24 weeks of supervised training. Methods Thirty-six healthy middle-aged adults (55.6 ± 5.3 yr) were randomly assigned into Tai-Chi, running and control groups. During a 24-week training period, the Tai-Chi and running groups were asked to perform exercises for 60 min/day and 5 days/week, which were supervised by Tai-Chi and running instructors throughout. Resting heart rate, lean mass, blood pressure and blood lipids were measured, and cardiorespiratory fitness (VO2max, Vmax and Peak heart rate) was assessed at the baseline and the 12- and 24-week interventions. Results Compared to the no-exercise control group, both the Tai-Chi and running groups significantly decreased resting heart rate, diastolic blood pressure and cardiorespiratory fitness and increased lean mass across the training session (p < 0.05). Compared to the Tai-Chi group, the running group showed greater improvement in VO2max and Vmax (p < 0.05) and reduced triglyceride and low-density lipoprotein cholesterol (p < 0.05). Conclusion Both Tai-Chi and running exercise showed beneficial effects on cardiorespiratory fitness and enhanced health-related outcomes in middle-aged adults. Although Tai-Chi exercises were less effective in VO2max than running, Tai-Chi may be considered as a plausible alternative to running exercises that can be achieved in the indoor-based setting. [ABSTRACT FROM AUTHOR]

Simple Summary: Calf muscles, including the gastrocnemius and soleus muscles, are very important for soccer players, but the benefits of soleus stretching are rarely reported. Both regular and soleus stretching conditions lead to better ankle range of motion, maximum plantarflexion strength, dynamic balance and speed performances compared to the no-stretching control. Adding soleus stretches into the regular stretching protocol would allow further improvement of ankle flexibility, maximum plantarflexion strength and curved running speed performances. The results from this study can provide insights for pre-exercise design and subsequent performances in soccer. Most dynamic stretching protocols include the gastrocnemius muscle, but soleus stretches are often neglected, which is the key powerful muscle for the push-off (concentric) of all speed movements. The purpose of this study was to examine whether the added soleus stretch in a regular stretching protocol would have greater benefits for ankle flexibility, dynamic balance and functional performance. Fourteen healthy male soccer players received each of the stretching conditions (regular stretching only (Regular), regular stretching with soleus stretching (Soleus) and no stretching (Control)) randomly on different training days, with two-day separation. The ankle flexibility, standing heel-lift balance and speed performances were assessed following each stretching intervention. The active dynamic stretches were performed for 30 s with three repetitions on each of the three (Regular) and four (Soleus) muscles. One-way ANOVA with repeated measures (or the Friedman non-parametric test) was performed to determine any significant effect with alpha = 0.05. Our findings revealed that both the Regular and Soleus stretching groups showed an increased active range of ankle motion compared to the no-stretching control (Ps < 0.05). In the heel raise balance test, both stretching groups experienced a significant increase in maximum plantarflexion strength as well as resultant anterior–posterior and medial–lateral CoP excursions compared to the no-stretching control (Ps < 0.05). In the sprinting tasks, both the Soleus and Regular stretching groups induced faster linear and curved running times (Ps < 0.05). When comparing the two stretching groups, Soleus stretching led to better ankle flexibility, maximum plantarflexion strength and curved running time (Ps < 0.05). Thus, added stretches on the soleus muscles can provide further benefits to speed performances in soccer. [ABSTRACT FROM AUTHOR]

This study examined the differences of muscle strength, electromyography (EMG) and whole-body kinematics during maximum cross-step table tennis topspin between advanced and intermediate players. Ten advanced and ten intermediate players performed both voluntary isokinetic contraction test and forehand topspin strokes with maximum-effort towards cross-court target zone. The results indicated that advanced players generated significantly greater maximum racket speeds during forward swing phase (P < 0.05). At the instant of the topspin stroke, significantly smaller shoulder horizontal flexion and elbow flexion angles, but larger joint angular velocities in advanced players (P < 0.05). Moreover, advanced players exhibited longer muscle firing duration of anterior deltoid and biceps brachii as well as higher root mean squares and EMG integrals of the abdominal external oblique, anterior deltoid and biceps brachii muscles than the intermediate players (P < 0.05). Furthermore, the isokinetic results showed higher shoulder abduction/adduction, hip flexion/extension and knee flexion torques at fast speed (240°/s) and higher elbow flexion torque at medium speed (120°/s) in advanced players (P < 0.05). The findings suggest that higher activation of the deltoid, biceps and abdominal external oblique muscles as well as larger muscle strength under higher speed conditions would be the plausible key factors to maximise racket and joint angular velocities in forehand topspin. [ABSTRACT FROM AUTHOR]