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Background: Spiroergometry is important for modern performance diagnostics, and reference values have been evaluated for bicycle and treadmill ergometers. The aim of this study is to assess the comparability of bicycle and hand-crank spiroergometry and its associated parameters, as hand-crank spiroergometry can be used during rehabilitation in patients with definitive or temporally impairment of the lower extremity. Methods: Thirty-seven healthy volunteers completed 2 exhausting performance diagnostics on hand-crank and bicycle spiroergometry. Participants' anthropometric characteristics, maximum power, multiple exertion criteria, maximum aerobic capacity, and maximum heart rate were detected, and ventilatory and metabolic thresholds were determined. Results: The maximum power, maximum heart rate, maximum aerobic capacity, and ventilatory thresholds were significant higher on the bicycle ergometer (P <.001). The metabolic thresholds occurred on higher lactate values on the hand-crank ergometer. Equations for calculating maximum aerobic capacity from the maximum power measured in either hand-crank or bicycle ergometer could be found through regression analysis. Conclusions: Although there are problems in interpreting results of different ergometries due to severe physiology differences, the equations can be used for patients who are temporally unable to complete the established ergometry due to a deficit in the lower extremity. This could improve training recommendations for patients and para-athletes in particular. [ABSTRACT FROM AUTHOR]

Context: Ankle sprains are a common injury in sports, for which use of external ankle support during rehabilitation has been suggested to improve clinical outcomes. Design: Cohort study. Methods: Thirteen soccer players experiencing acute lateral ankle sprain injury were provided a novel adaptive ankle brace or conventional ankle taping (control) as external ankle support throughout the injury rehabilitation process. All other clinical procedures were identical, and rehabilitation was supervised by the same team staff member. Time from injury to clearance to return to sport was tracked. Player experience with the ankle brace also was queried via electronic surveys. Results: The median time to return to sport was less for the Brace group (52.5 d) compared to the Control group (79.5 d), but the distributions of the 2 groups were not found to differ significantly (P =.109). Player surveys indicated they felt the brace to be comfortable or very comfortable, with better freedom of movement than other braces and the same freedom of movement as wearing no brace. All players reported wearing the brace to be the same or better experience as ankle taping. Discussion: These preliminary results indicate that the adaptive ankle brace is at least as effective as ankle taping for providing external support during the rehabilitation phase following acute lateral ankle sprain and suggest it may be a more effective ankle support solution in terms of patient compliance than conventional bracing or taping. [ABSTRACT FROM AUTHOR]

Context: We designed this study to investigate the effects of 2 myofascial release techniques, Instrument-Assisted Soft Tissue Mobilization (IASTM) and Foam Roller (FR), on pain, joint range of motion, and muscle strength in athletes suffering from iliotibial band (ITB) tightness. Design: A total of 39 male soccer players were enrolled in this randomized controlled trial, aged between 18 and 23 years who were divided into 3 groups: Only Exercise, IASTM, and FR. Methods: All participants performed daily strengthening and stretching exercises, while 1 group added IASTM, and the other added FR to the exercise program. We evaluated ITB tightness with the Ober test and an inclinometer, pressure pain threshold, using an algometer, and we evaluated muscle strength with the Cybex Norm Isokinetic device. Results: We found that all 3 groups exhibited an increase in the Ober inclination angle after the interventions (P =.001), but the increase was greater for participants in the IASTM and FR groups, compared with exercise alone. Additionally, both the IASTM and FR groups displayed an increased pressure pain threshold (P =.001), whereas there was no change in the control group. Moreover, while all 3 groups experienced an increase in hip muscle strength (P =.001), the IASTM and FR groups exhibited a greater increase compared with exercise alone (P =.001). Conclusions: Based on these findings, exercise improves pain, range of motion, and muscle strength in athletes with ITB tightness, and IASTM, and FR techniques enhanced exercise effects but did not differ from one another. While our study demonstrated that both IASTM and FR techniques significantly enhance the benefits of exercise for athletes with ITB tightness, further research could delve into the long-term effects of these interventions. [ABSTRACT FROM AUTHOR]

Context: To stabilize the humeral head within the glenoid fossa during arm elevation, the rotator cuff muscles may contribute through internal and external rotation. The main purpose of the current study was to compare the acromiohumeral distance between athletes with primary subacromial impingement syndrome who received progressive resistance exercises consisting of either shoulder internal or external rotation. Design: A randomized and controlled clinical study. Methods: Thirty athletes with primary subacromial impingement syndrome were enrolled and randomly divided into 2 experimental groups. The progressive resistance exercise protocol in experimental group I comprised shoulder internal rotation, while in experimental group II consisted of shoulder external rotation. The experimental groups worked out 3 days a week for 6 weeks. The experimental groups were compared with the control group consisting of 15 healthy athletes. The acromiohumeral distance was measured before and after the intervention using an ultrasound machine under the passive and active across no arm elevation and 45°of arm elevation. Results: The acromiohumeral distance significantly increased in both experimental groups under the passive and active arm positions following the intervention (P <.001), with no significant differences detected between the experimental groups (P >.665). The paired comparisons of the acromiohumeral distance discrepancy indicated a significant difference between the control group and each experimental group under the active and passive arm positions (P <.001), while no significant difference was observed between the experimental groups (P >.999). Conclusions: The present study revealed, for the first time, that both progressive resistance exercise protocols involving either the shoulder internal or the external rotation increased the acromiohumeral distance in individuals with primary subacromial impingement syndrome and improved associated pain and disabilities. [ABSTRACT FROM AUTHOR]

In the contemporary digital age, continued online learning behaviors have become indispensable for fostering employee development. However, the learning and development literature predominantly focuses on traditional instructor‐led approaches. It remains unclear how organizations can shape employees' learning behaviors, particularly in the context of online learning. The current study clarifies this underexplored research area by investigating how organizational investment in employee developmental climate (IEDC) can promote employees' continued online learning behaviors. Drawing on social influence theory and employing a multilevel research design, we find empirical support for our research model, which specifies that IEDC positively affects employees' continued online learning behaviors through the effect of normative pressure. The findings also reveal the moderating role of online learning facilitating conditions. Specifically, in firms characterized by higher levels of online learning facilitating conditions, the positive relationship between IEDC and normative pressure becomes more pronounced when compared to organizations with lower levels of such facilitating conditions. [ABSTRACT FROM AUTHOR]

Research interest in thriving at work has burgeoned over the past decades, but little is known about how human resource (HR) practices affect employees' thriving at work. Drawing upon self‐determination theory and person‐organization fit theory, we developed and tested a moderated mediation model to explain how fun HR practices influence employees' thriving at work. The results of two studies, a scenario experiment (N = 164) and a time‐lagged survey (N = 253), supported our hypotheses. Specifically, the findings revealed that fun HR practices relates positively to employees' thriving at work. Autonomous motivation partially mediates the abovementioned relationship. Furthermore, fun HR practices translate into higher autonomous motivation and subsequent thriving at work for employees with higher preference for workplace fun. Our research contributes to the existing literature by identifying fun HR practices as an antecedent of thriving at work and revealing the psychological mechanisms through which fun HR practices affect employees' thriving at work. The practical implications, limitations, and future research avenues are also discussed. [ABSTRACT FROM AUTHOR]

Introduction: In distance running, pacing is characterized by changes in speed, leading to runners dropping off the leader's pace until a few remain to contest victory with a final sprint. Pacing behavior has been well studied over the last 30 years, but much remains unknown. It might be related to finishing position, finishing time, and dependent on critical speed (CS), a surrogate of physiologic capacity. We hypothesized a relationship between CS and the distance at which runners "fell behind" and "let go" from the leader or were "outsprinted" as contributors to performance. Methods: 100-m split times were obtained for athletes in the men's 10,000-m at the 2008 Olympics (N = 35). Split times were individually compared with the winner at the point of "falling behind" (successive split times progressively slower than the winner), "letting go" (large increase in time for distance compared with winner), or "outsprinted" (falling behind despite active acceleration) despite being with the leader with 400 m remaining. Results: Race times ranged between 26:55 and 29:23 (world record = 26:17). There were 3 groups who fell behind at ∼1000 (n = 11), ∼6000 (n = 16), and ∼9000 m (n = 2); let go at ∼4000 (n = 10), ∼7000 (n = 14), and ∼9500 m (n = 5); or were outkicked (n = 6). There was a moderate correlation between CS and finishing position (r =.82), individual mean pace (r =.79), "fell behind" distance (r =.77), and "let go" distance (r =.79). D′ balance was correlated with performance in the last 400 m (r =.87). Conclusions: Athletes displayed distinct patterns of falling behind and letting go. CS serves as a moderate predictor of performance and final placing. Final placing during the sprint is related to preservation of D′ balance. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated the test–retest reliability and usefulness of the foot–ankle rebound-jump test (FARJT) for measuring foot–ankle reactive strength metrics in athletes. Methods: Thirty-six highly trained, healthy athletes (5 female; 21.5 [3.9] y; 1.80 [0.10] m; 72.7 [10.4] kg) performed 8 repeated bilateral vertical foot–ankle rebound jumps on 2 testing days. Testing days were 1 week apart, and these sessions were preceded by a familiarization session. Reactive strength metrics were calculated by dividing jump height (in meters) by contact time (in seconds) for the reactive strength index (RSI) and flight time (in seconds) by contact time (in seconds) for the reactive strength ratio (RSR). The mean of 4 jumps (excluding the first and last 2 jumps) on each testing session were considered for RSI and RSR reliability and usefulness analysis. Results: We found a high reliability of the FARJT for RSI (intraclass correlation coefficient [ICC] >.90 and coefficient of variation [CV] = 12%) and RSR (ICC ≥.90 and CV = 8%). Regarding their usefulness, both RSI and RSR were rated as "marginal" in detecting the smallest worthwhile change (typical error > smallest worthwhile change) and "good" in detecting a moderate change in performance. Conclusions: The results showed that a FARJT is a highly reliable test for measuring foot–ankle reactive strength in athletes and useful for quantifying changes, for example, following a training block. However, its usefulness as an accurate daily or weekly monitoring tool in practice is questionable. [ABSTRACT FROM AUTHOR]

Purpose: Performing back squats with elastic bands has been widely used in resistance training. Although research demonstrated greater training effects obtained from adding elastic bands to the back squat, little is known regarding the optimal elastic resistance and how it affects neuromuscular performance. This study aimed to compare the force, velocity, power, and muscle activity during back squats with different contributions of elastic resistance. Methods: Thirteen basketball players performed 3 repetitions of the back squat at 85% of 1-repetition maximum across 4 conditions: (1) total load from free weight and (2) 20%, (3) 30%, and (4) 40% of the total load from elastic band and the remaining load from free weight. The eccentric and concentric phases of the back squat were divided into upper, middle, and bottom phases. Results: In the eccentric phase, mean velocity progressively increased with increasing elastic resistance, and muscle activity of the vastus medialis and rectus femoris significantly increased with the largest elastic resistance in the upper phase (P ≤.036). In the concentric phase, mean power (P ≤.021) and rate of force development (P ≤.002) significantly increased with increasing elastic resistance. Furthermore, muscle activity of the vastus lateralis and vastus medialis significantly improved with the largest elastic resistance in the upper phases (P ≤.021). Conclusion: Velocity, power, rate of force development, and selective muscle activity increased as the elastic resistance increased in different phases during the back-squat exercise. [ABSTRACT FROM AUTHOR]

Purpose: The relationship between external load and creatine-kinase (CK) response at the team/position or individual level using Global Positioning Systems (GPS) has been studied. This study aimed to compare GPS-derived and Football Movement Profile (FMP) –derived CK-prediction models for national-team soccer players. The second aim was to compare the performance of general and individualized CK prediction models. Methods: Four hundred forty-four national-team soccer players (under 15 [U15] to senior) were monitored during training sessions and matches using GPS. CK was measured every morning from whole blood. The players had 19.3 (18.1) individual GPS-CK pairs, resulting in a total of 8570 data points. Machine learning models were built using (1) GPS-derived or (2) FMP-based parameters or (3) the combination of the 2 to predict the following days' CK value. The performance of general and individual-specific prediction models was compared. The performance of the models was described by R2 and the root-mean-square error (RMSE, in units per liter for CK values). Results: The FMP model (R2 =.60, RMSE = 144.6 U/L) performed similarly to the GPS-based model (R2 =.62, RMSE = 141.2 U/L) and the combination of the 2 (R2 =.62, RMSE = 140.3 U/L). The prediction power of the general model was better on average (R2 =.57 vs R2 =.37) and for 73% of the players than the individualized model. Conclusions: The results suggest that FMP-based CK-prediction models perform similarly to those based on GPS-derived metrics. General machine learning models' prediction power was higher than those of the individual-specific models. These findings can be used to monitor postmatch recovery strategies and to optimize weekly training periodization. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to determine whether the initial levels of aerobic fitness and hematological variables in young female road cyclists are related to their athletic performance development during their careers. Methods: Results of graded exercise tests on a cycle ergometer and total hemoglobin mass (tHb-mass) measurements were analyzed in 34 female road cyclists (age 18.6 [1.9] y). Among them, 2 groups were distinguished based on their competitive performance (Union Cycliste Internationale world ranking) over the following 8 years. Areas under the curve in receiver-operating-characteristic curves were calculated as indicators of elite-performance prediction. Results: Initial graded exercise test variables (peak power, peak oxygen uptake, and power at 4 mmol/L blood lactate) were not significantly different in elite (n = 13) versus nonelite (n = 21) riders. In contrast, elite riders had higher tHb-mass expressed either in absolute measures (664 [75] vs 596 [59] g, P =.006) or normalized to body mass (11.2 [0.8] vs 10.3 [0.7] g/kg, P =.001) and fat-free mass (14.4 [0.9] vs 13.1 [0.9] g/kg, P <.001). Absolute and relative erythrocyte volumes were significantly higher in elite subjects (P ranged from <.001 to.006). Of all the variables analyzed, the relative tHb-mass had the highest predictive ability to reach the elite level (area under the curve ranged from.82 to.85). Conclusion: Measurement of tHb-mass can be a helpful tool in talent detection to identify young female road cyclists with the potential to reach the elite level in the future. [ABSTRACT FROM AUTHOR]

Purpose: To examine associations between exercise heart rate (HRex) during a continuous-fixed submaximal fitness test (CF-SMFT) and an intermittent-variable protocol (semistandardized kicking drill [SSD]) in Australian Football athletes, controlling for external intensities, within-session scheduling, and environmental conditions. Methods: Forty-four professional male Australian Football athletes (22.8 [8.0] y) were monitored over 10 sessions involving a 3-minute CF-SMFT (12 km·h−1) as the first activity and a SSD administered 35.7 (8.0) minutes after the CF-SMFT. Initial heart rate and HRex were collected, with external intensities measured as average velocity (in meters per minute) and average acceleration–deceleration (in meters per second squared). Environmental conditions were sampled. A penalized hierarchical linear mixed model was tuned for a Bayesian information criterion minima using a 10-fold cross-validation, with out-of-sample prediction accuracy assessed via root-mean-squared error. Results: SSD average acceleration–deceleration, initial heart rate, temperature, and ground hardness were significant moderators in the tuned model. When model covariates were held constant, a 1%-point change in SSD HRex associated with a 0.4%-point change in CF-SMFT HRex (95% CI, 0.3–0.5). The tuned model predicted CF-SMFT HRex with an average root-mean-squared error of 2.64 (0.57) over the 10-fold cross-validation, with 74% and 86% of out-of-sample predictions falling within 2.7%-points and 3.7%-points, respectively, from observed values, representing the lower and upper limits for detecting meaningful changes in HRex according to the documented typical error. Conclusions: Our findings support the use of an SSD to monitor physiological state in Australian Football athletes, despite varied scheduling within session. Model predictions of CF-SMFT HRex from SSD HRex closely aligned with observed values, considering measurement imprecision. [ABSTRACT FROM AUTHOR]

Purpose: To compare the kinematic profile of 2 underwater pullout breaststroke techniques. Methods: Sixteen swimmers (9 men, 20.67 [2.71] y old; 7 women, 18.86 [0.83] y old) performed 3 × 25-m breaststroke using 2 pullout breaststroke techniques: Fly-Kick first and Combined. A speedometer was used to assess the peak and the mean velocity during the glide, propulsion, and recovery phases of both techniques, as well as for the total underwater sequence. The underwater distance was retrieved from video footage and was considered for each pullout technique. The range of motion of the knee during the fly-kick was also retrieved, and the time to complete the 25 m was considered the performance outcome, accompanied by the mean velocity, stroke rate, stroke length, and stroke index. Results: Velocity–time series showed different profiles between pullout techniques (P ≤.05) mostly in the glide and propulsion phases for males and females, respectively. The mean velocity of 25 m was shown to be greater in females when using the Fly-Kick first technique (P =.05, d = 0.36). Greater values in total underwater distance and knee range of motion were also observed for this technique in both cohorts. Conclusions: Female swimmers presented a higher performance when using the Fly-Kick first technique. Different kinematic profiles arise when swimmers use different underwater pullout techniques where the Fly-Kick first may allow them to reach higher kinematical standard. [ABSTRACT FROM AUTHOR]

Musculoskeletal modeling, typically implemented using marker-based systems in laboratory environments, is commonly used for noninvasive estimations of loads. Inertial measurement units (IMUs) have become an alternative for the evaluation of kinematics. However, estimates of spine joint contact forces using IMUs have yet to be thoroughly evaluated. Dynamics tasks and static postures from activities of daily living were captured on 11 healthy subjects using both systems simultaneously. Spine kinematics obtained from IMU- and marker-based systems and L4–L5 joint contact forces were compared. Lateral bending resulted in a weak agreement with significant differences between the 2 systems (P =.02, average root mean-squared error = 4.81), whereas flexion–extension and axial rotation exhibited the highest agreement with no significant differences (P <.05, average root mean-squared error = 5.51 and P <.31, average root mean-squared error = 5.08, respectively). All tasks showed excellent correlations (R2 =.76–.99) in estimated loads between systems. Differences in predicted loads at the L4–L5 were only observed during flexion–extension (1041 N vs 947 N, P =.0004) and walking with weights (814 N vs 727 N, P =.004). Different joint reaction force outcomes were obtained in 2 of the 8 tasks between systems, suggesting that IMUs can be robust tools allowing for convenient and less expensive evaluations and for longitudinal assessments inside and outside the laboratory setting. [ABSTRACT FROM AUTHOR]

Assessment of player's postural control following a lower limb injury is of interest to sports medicine practitioners due to its fundamental role in daily tasks and sporting activities. The aim was to longitudinally monitor professional rugby union players' postural control during each phase of the rehabilitation program (acute, middle, and late) following a lower limb injury. Seven male rugby union players (height 1.80 [0.02] m; mass 100.3 [11.4] kg; age 24 [4] y) sustained a time loss, noncontact lower limb injury. Static postural control was assessed via sway path (in meters), and dynamic postural control was assessed via vertical postural stability index. Group differences (P <.05) were reported across the acute, middle, and late phase. Smaller magnitudes of sway path were observed for eyes-open sway path, and for the middle and late phase smaller magnitudes of vertical postural stability index (P <.05) at the end session compared with first session. Whereas larger magnitudes of vertical postural stability index were found between baseline and the last session (P <.05). Large interindividual and intraindividual variation was apparent across the 3 phases of rehabilitation. Postural control improvements were identified during rehabilitation. However, postural control did not return to baseline, with altered kinetics throughout each rehabilitation phase. [ABSTRACT FROM AUTHOR]

We aimed to investigate the effects of dual- and single-task training in older adults with age-related hearing loss. Intervention groups included single-, dual-task training, and control groups. The dual- and single-task trainings were held 2 days a week for 40 min for a total of 10 sessions for 5 weeks. We evaluated physical, cognitive, and auditory functions, quality-of-life, balance, concerns about falling, independence in activities of daily living, and dual-task performance. A total of 42 patients fully participated in this study. Statistically significant differences were observed in chair stand, chair sit-and-reach, global cognitive function, and delayed recall between the intervention groups and control group (p <.05). There was no statistically significant difference in quality-of-life, balance, falling concerns, independence in activities of daily living, and dual-task performance between all groups (p >.05). In conclusion, single- and dual-task training had a positive effect on physical and cognitive functioning in older adults with age-related hearing loss. [ABSTRACT FROM AUTHOR]

Previous research has explored the physical activity habits of people with dementia and their family carers separately, with little consideration of how physical habits are associated within dyads. In this observational study, we sought to explore the relationship between people with dementia and their carers' physical activity, at a group level and at a dyadic level. Twenty-six participant dyads (persons with dementia and their carer spouses) were asked to wear an accelerometer for 30 days continuously. Comparisons were made at a group level and a dyadic level. People with dementia did not participate in significantly more moderate to vigorous physical activity (M = 15.44 min/day; SD = 14.40) compared with carers (M = 17.95 min/day; SD = 17.01). Within dyads, there were moderately strong associations between daily moderate to vigorous physical activity (r =.48–.54), but not with overall activity levels (r =.24). Despite physical activity habits remaining relatively low within people with dementia and carers, respectively, moderate to vigorous physical activity levels appear to be correlated within dyads. Understanding mutual influence on physical activity levels within dyads is an important pathway to promote an active lifestyle. [ABSTRACT FROM AUTHOR]

Background/Objectives: This study investigated adherence to physical activity (PA) guidelines and associated sociodemographic factors among older Koreans from 2011 to 2020. Methods: Utilizing four public data sets from the National Survey of Older Koreans, the study included the data on 40,993 older adults 65 years and older in South Korea, collected between 2011 and 2020. Adherence to PA guidelines and sociodemographic factors were assessed through self-reported questionnaires. The data were analyzed using a two-way analysis of variance and post hoc tests. Results: Overall adherence increased from 39.1% in 2011 to 48.2% in 2017, then decreased to 37.6% in 2020 (p <.001). Men had higher adherence than women (p <.001). Age-related adherence peaked in the young-older group (65–74 years old) and was lowest in the oldest-old group (85+ years old) (p <.001). Marital status, education, and income were also significantly related to PA adherence (p <.001) across the years. Conclusion: Although continuous increase in adherence to PA among Koreans 65 years and older was observed, the decline in PA levels during the COVID era underscored the need for targeted interventions and well-informed health care policies to address demographic challenges. Still, considering that data were collected during the recommended social distancing period, a cautions interpretation of these findings is warranted. Significance/Implications: Health policies aiming to improve adherence to PA guidelines should prioritize Korean older adults who are female, belong to the oldest-old group, are single, and have low education and income levels, with the goal of enhancing health equity. [ABSTRACT FROM AUTHOR]

Purpose: To investigate how cycling time-trial (TT) performance changes over a cycling season, both in a "fresh" state and in a "fatigued" state (durability). Additionally, the aim was to explore whether these changes are related to changes in underlying physiological factors such as gross efficiency, energy expenditure (EE), and substrate oxidation (fat oxidation [FatOx] and carbohydrate oxidation [CarbOx]). Methods: Sixteen male semiprofessional cyclists visited the laboratory on 3 occasions during a cycling season (PRE, START, and IN) and underwent a performance test in both fresh and fatigued states (after 38.1 [4.9] kJ/kg), containing a submaximal warm-up for the measurement of gross efficiency, EE, FatOx, and CarbOx and a maximal TT of 1 (TT1min) and 10 minutes (TT10min). Results were compared across states (fresh vs fatigued) and periods (PRE, START, and IN). Results: The average power output (PO) in TT1min decreased (P <.05) from fresh to fatigued state across all observed periods, whereas there was no change in the PO in TT10min. Over the course of the season, the PO in TT1min in the fatigued state improved more compared with the PO in TT1min in the fresh state. Furthermore, while EE did not significantly change, there was an increase in FatOx and a decrease in CarbOx toward the fatigued state. These changes diminished during the cycling season (IN), indicating a greater contribution of CarbOx in the fatigued state. Conclusions: TT1min performance is more sensitive to fatigue compared with TT10min. Also, during a cycling season, durability improves more when compared with fresh maximal POs, which is also observed in the changes in substrate oxidation. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to enhance the understanding of soccer match peak demands by describing worst-case scenario (WCS) and time spent above 80% and 90% of the WCS for total distance (TD) and high-speed running (HSR). The investigation considered playing level (first team vs under-19 [U19] team) and playing position (center backs, fullbacks, midfielders, and forwards) to assess how WCS and the time spent above specific thresholds vary across different populations. Methods: Data from 31 players in a professional Italian soccer club were collected during the 2022–23 season. Microtechnology devices tracked physical activity during matches. Players were categorized by position, and WCS was determined using rolling averages over a 1-minute period. Time spent above 80% and 90% of WCS for TD and HSR was calculated. Results: The U19 team exhibited higher HSR WCS compared with the first team (∼63 m·min−1 vs ∼56 m·min−1). Midfielders recorded the highest TD WCS (∼208 m·min−1), and forwards exhibited the highest HSR WCS (∼70 m·min−1). The first team spent significantly more time above 80% (∼6 min) and 90% (∼1 min) of TD WCS. Midfielders spent significantly more time above the 80% (∼7 min) of TD WCS, while forwards above the 80% (∼2 min) of HSR WCS. Conclusions: The study emphasizes that WCS used alone may not sufficiently capture real match intensity. Considering the time spent above specific thresholds provides additional insights (ie, between-levels differences and position). Practitioners should consider both WCS and time spent above thresholds for individualized training prescriptions, reflecting differences in playing roles. [ABSTRACT FROM AUTHOR]

This study investigates the stability of the (Hf,Zr)O2 (HZO) and AlScN thin films against the depolarization effect. In order to adversely interfere with the polarization screening of ferroelectric (FE) film and induce the depolarization effect, an Al2O3 film was inserted between the TiN bottom electrode and the FE film. Subsequently, to minimize charge injection through Al2O3 films, the double remanent polarization–voltage (2Pr–V) curve was measured employing voltage pulses with 1 μs-length. As the thickness of the Al2O3 film increased, the charge injection through the Al2O3 film decreased, leading to a decrease in the slope of the 2Pr–V curve. The magnitude of the depolarization field applied to the FE film was determined by simulating the 2Pr–V curve using an equivalent circuit model. Subsequently, the proportion of reversed domains during the delay period due to the depolarization effect was measured. It was revealed that HZO films exhibited vulnerability to the depolarization effect, with 16% of domains being reversed. On the other hand, AlScN films demonstrated superior stability, with polarization loss of less than 1%. Ultimately, it was revealed that AlScN films demonstrated superior stability against the depolarization effect compared to HZO films due to their higher coercive field and more uniform polarization distribution across the film area. [ABSTRACT FROM AUTHOR]

Traditionally, stress fluctuations in flowing and deformed materials are overlooked, with an obvious focus on average stresses in a continuum mechanical approximation. However, these fluctuations, often dismissed as "noise," hold the potential to provide direct insights into the material structure and its structure-stress coupling, uncovering detailed aspects of fluid transport and relaxation behaviors. Despite advancements in experimental techniques allowing for the visualization of these fluctuations, their significance remains largely untapped as modeling efforts continue to target Newtonian fluids within the confines of Gaussian noise assumptions. In the present work, a comparative analysis of stress fluctuations in two distinct microstructural models is carried out: the temporary network model and the hydrodynamic dumbbell model. Despite both models conforming to the upper convected Maxwell model at a macroscopic level, the temporary network model predicts non-Gaussian fluctuations. We find that stress fluctuations within the temporary network model exhibit more pronounced abruptness at the local scale, with only an enlargement of the control volume leading to a gradual Gaussian-like noise, diminishing the differences between the two models. These findings underscore the heightened sensitivity of fluctuating rheology to microstructural details and the microstructure–flow coupling, beyond what is captured by macroscopically averaged stresses. [ABSTRACT FROM AUTHOR]

Individuals with intellectual disabilities often face unique challenges in physical capabilities, making traditional training methods less effective for their specific needs. This study aimed to investigate the effect of combining balance, plyometric, and strength (CBPS) training with sprint training on physical performance in male athletes with intellectual disabilities. Twenty-seven participants were randomly assigned to either a CBPS group or a control group that only maintained their regular sprint training. Participants underwent pre- and posttraining tests, including measures of balance, jumping, agility, and sprinting ability. The results showed that the CBPS group demonstrated significant improvements (p <.05) in one-leg stance, crossover-hop jump, squat jump, countermovement jump, and 10- and 30-m sprint at posttraining compared with pretraining. CBPS training combined with sprinting significantly improves physical performance in male athletes with intellectual disabilities, suggesting implications for tailored training programs to enhance their physical fitness and overall health. [ABSTRACT FROM AUTHOR]

Introduction: Unlike the most common training approaches for bodybuilding, powerlifting programs are generally based on maximum and submaximal loads, putting enormous stresses on the lumbar spine. The flexion relaxation phenomenon evaluation is a clinical tool used for low back pain (LBP) assessment. This study aimed to evaluate the role of the flexion relaxation phenomenon in the analysis of LBP in the powerlifters. Methods: Healthy professional powerlifters participated in the study. In fact, we divided the participants into a LBP-low-risk group and a LBP-high-risk group, based on a prior history of LBP. Outcome measures included flexion relaxation ratio (FRR) and trough surface electromyography collected during trunk maximum voluntary flexion; furthermore, during a bench press lifting, we measured the height of the arched back (ARCH), using a camera and the Kinovea video editing software, to consider a potential correlation with the risk of LBP. Results: We included a group of 18 male (aged 24–39 y) powerlifters of 93 kg category. We measured a nonsignificant mean difference of ARCH between low-risk LBP group and high-risk LBP subjects. Curiously, maximum voluntary flexions were both above the threshold of 3.2 μV; therefore, with an absence of appropriate myoelectric silence, on the contrary, the FRR ratios were higher than 9.5, considering the presence of the phenomenon, exclusively for the low-risk group. The lumbar arched back measurement data did not report any association with the LBP risk, regarding the maximum voluntary flexion value, and even more than the FRR there is a relationship with the presence or the absence of LBP risk. Conclusions: FRR could be considered as a useful parameter for studying the risk of LBP in powerlifting. The FRR index not only refers to the possible myoelectric silence of the lumbar muscles in trunk maximum forward flexion but also takes into account the energy value delivered by the lumbar muscles during the flexion. Furthermore, we can indicate that the size of the powerlifter ARCH may not be a determining factor in the occurrence of LBP. [ABSTRACT FROM AUTHOR]

Context: The persistence and the recurrence of posterior medial knee pain (PKP) after anterior cruciate ligament reconstruction (ACLR) using hamstring tendon graft are often overlooked during rehabilitation. Design: Cross-sectional observational study. Methods: The study aimed (1) to evaluate the prevalence of these types of PKP before 4 months post-ACLR, (2) to measure their consequences on the knee flexors strength, and (3) to evaluate the role of the type of ACLR. From a cohort of patients operated on with hamstring tendon procedures, the persistent and the recurrent PKP were sought at 4 months post-ACLR. The evolution of isokinetic muscle strength recovery in PKP subjects was compared with those of nonpainful subjects. The functional deficit was measured at 6/7 months post-ACLR by a hop test. Results: Three hundred seventeen subjects (25.8 [6.0] y) were included. At 4 months post-ACLR, 2 populations were identified based on the recurrent onset of PKP (PKP+, n = 40) or the absence of knee pain (PKP−, n = 277). The prevalence of PKP was 8.3%. At the fourth month post-ACLR, the PKP+ group had a higher flexor strength deficit compared with the PKP− group (limb symmetry index at 60°/s: 67.2% [12.4%] vs 84.3% [12.6%]; P <.05). At 6/7 months, the loss of strength persisted (limb symmetry index at 60°/s: 82.3% [13.4%] vs 87.7% [12.8%]; P <.05). The hop test deficit was comparable, and no difference was shown according to the type of graft. Conclusions: Persistent and recurrent PKP during the rehabilitation period were not uncommon and were associated with a worsening of flexors strength loss on the ACLR side. [ABSTRACT FROM AUTHOR]

The cyclical changes in sex hormones across the menstrual cycle (MC) are associated with various biological changes that may alter resting metabolic rate (RMR) and body composition estimates. Hormonal contraceptive (HC) use must also be considered given their impact on endogenous sex hormone concentrations and synchronous exogenous profiles. The purpose of this study was to determine if RMR and dual-energy X-ray absorptiometry body composition estimates change across the MC and differ compared with HC users. This was accomplished during a 5-week training camp involving naturally cycling athletes (n = 11) and HC users (n = 7 subdermal progestin implant, n = 4 combined monophasic oral contraceptive pill, n = 1 injection) from the National Rugby League Indigenous Women's Academy. MC phase was retrospectively confirmed via serum estradiol and progesterone concentrations and a positive ovulation test. HC users had serum estradiol and progesterone concentrations assessed at the time point of testing. Results were analyzed using general linear mixed model. There was no effect of MC phase on absolute RMR (p =.877), relative RMR (p =.957), or dual-energy X-ray absorptiometry body composition estimates (p >.05). There was no effect of HC use on absolute RMR (p =.069), relative RMR (p =.679), or fat mass estimates (p =.766), but HC users had a greater fat-free mass and lean body mass than naturally cycling athletes (p =.028). Our findings suggest that RMR and dual-energy X-ray absorptiometry body composition estimates do not significantly differ due to changes in sex hormones in a group of athletes, and measurements can be compared between MC phases or with HC usage without variations in sex hormones causing additional noise. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to compare the maximum and rapid force production of Spanish football players and explore the differences between age group and level of competition. Methods: A cross-sectional study was developed to evaluate the peak force (PF), relative PF, and rate of force development over 250 ms (RFD0−250) during the isometric midthigh pull between groups of football players based on age group (senior vs junior) and level of competition (national vs regional). Using a portable isometric rig, 111 football players performed 2 isometric midthigh-pull trials on a force plate. Two-way analysis of variance with Bonferroni post hoc correction was applied, and statistical significance was set at P ≤.05. The PF, relative PF, and RFD0−250 0, 25, 50, 75, and 100 percentiles were also calculated and descriptively reported, separated by age group and level of competition. Results: The analysis of variance revealed a significant main effect of the level of competition for the PF (P <.001), relative PF (P =.003), and RFD0−250 (P <.001). There was a significant main effect of age group for the PF (P <.001). There was a significant interaction effect of the age group × level of competition for relative PF (P =.014). National players were stronger than regional players on the PF and RFD0−250 (P <.001). Senior players were stronger than junior players for the PF (P <.001). Conclusions: Maximum and rapid force production are crucial for Spanish football players as they progress in both level of competition and age group. Practitioners should encourage young football players to prioritize strength development to improve their athletic performance. [ABSTRACT FROM AUTHOR]

Purpose: Determine the effects of advanced footwear technology (AFT) in track spikes and road-racing shoes on running economy (RE). Methods: Four racing shoes (3 AFT and 1 control) and 3 track spikes (2 AFT and 1 control) were tested in 9 male distance runners on 2 visits. Shoes were tested in a random sequence over 5-minute trials on visit 1 (7 trials at 16 km·h−1; 5-min rest between trials) and in the reverse/mirrored order on visit 2. Metabolic data were collected and averaged across visits. Results: There were significant differences across footwear conditions for oxygen consumption (F = 13.046; P <.001) and energy expenditure (F = 14.710; P <.001). Oxygen consumption (in milliliters per kilogram per minute) in both the first AFT spike (49.1 [1.7]; P <.001; dz = 2.1) and the other AFT spike (49.3 [1.7]; P <.001; dz = 1.7) was significantly lower than the control spike (50.2 [1.6]), which represented a 2.1% (1.0%) and 1.8% (1.0%) improvement in RE, respectively, for the AFT spikes. When comparing the subjects' most economic shoe by oxygen consumption (49.0 [1.5]) against their most economic spike (49.0 [1.8]), there were no statistical differences (P =.82). Similar statistical conclusions were made when comparing energy expenditure (in watts per kilogram). Conclusions: AFT track spikes improved RE ∼2% relative to a traditional spike. Despite their heavier mass, AFT shoes resulted in similar RE as AFT spikes. This could make the AFT shoe an attractive option for longer track races, particularly in National Collegiate Athletic Association and high school athletics, where there are no stack-height rules. [ABSTRACT FROM AUTHOR]

Purpose: To examine nocturnal sleep patterns, napping behaviors, and subjective wellness responses of elite water polo players within an in-season week and to identify whether sleeping patterns differ between men and women. Methods: Sleep characteristics of 10 male and 17 female professional water polo players were objectively assessed during 1 week of the in-season period, including 5 training days, 1 match day, and 1 day of rest. Internal load (rating of perceived exertion × duration of training or match) was assessed 30 minutes posttraining or postmatch, and the total quality of recovery was recorded every morning. A series of multilevel models were used to analyze the data. Results: Time in bed and wake-up time were earlier on both training (P <.001) and rest days (P <.001) than on the day of the match. Internal workload did not predict any of the players' sleeping patterns. Midday naps predicted less time in bed (P =.03) and likely less sleep time (P =.08). The total quality of recovery was predicted only by the total sleep time (P <.01). Women exhibited higher sleep efficiency (P <.001), less waking after sleep onset (P =.01), and a lower number of awakenings (P =.02) than men. Conclusions: The current results indicate that the nocturnal sleep patterns of elite water polo players are not associated with internal load and that women display better nocturnal sleep quality compared with men. As long naps interfere with nocturnal sleep, and total nocturnal sleep time predicts total quality of recovery, we suggest that athletes follow hygiene sleep strategies to facilitate adequate nocturnal sleep and next-day recovery. [ABSTRACT FROM AUTHOR]

Purpose: Successful participation in taekwondo (TKD) requires athletes to possess quick decision-making abilities and demonstrate technical proficiency during competition. Dehydration, occurring during both training and competition, is widely recognized to have various negative effects. Methods: This study investigated the impact of different levels of dehydration on cognitive function, as measured by the Vienna Test System, and the specific performance of kicking techniques among TKD athletes. Using a randomized crossover design, 12 participants were involved in the study. Before and after 1 hour of training at 80% of maximal heart rate, participants were weighed and provided urine samples. All participants were randomly assigned to 3 different hydration conditions: the euhydrated (EUH) group had unrestricted access to fluid consumption, while the hypohydrated (HYP) and severely HYP (S-HYP) groups experienced reductions of 2.0% and 4.0% of their initial body weight, respectively. Results: The EUH group exhibited better reaction speed in reaction-time test-form S1 than the HYP and S-HYP groups. Notably, the EUH group demonstrated a significantly higher success rate in the front-side kick (EUH 98%, HYP 90%, S-HYP 88%; P <.05). However, the success rates of back roundhouse kick and free head kick were similar among the 3 statuses. Furthermore, postexercise heart rates were found to be significantly higher in the HYP and S-HYP groups compared with the EUH group. Conclusions: This study provides insight into the negative effects of dehydration on cognitive function and TKD-specific performance. It is recommended that TKD athletes maintain optimal hydration levels during training and competition to ensure optimal performance. [ABSTRACT FROM AUTHOR]

This article investigated the effects of airborne-particle abrasion and nanosilica (nano-Si) infiltration treatment on the surface characteristics of dental zirconia. A total of 15 unsintered zirconia ceramic green bodies (10 × 10 × 3 mm) were divided into three groups (n = 5): Group C, no treatment after sintering; Group S, airborne-particle abrasion with 50-µm aluminum oxide particles after sintering; and Group N, infiltration of nano-Si followed by sintering and hydrofluoric acid (HF) etching. The zirconia disks' surface roughness was analyzed by atomic force microscopy (AFM). The surface morphology of the specimens was analyzed using scanning electron microscopy (SEM), and the chemical composition was analyzed by energy-dispersive x-ray (EDX). Data were statistically analyzed by Kruskal-Wallis test (P < .05). Zirconia surface treatments by infiltration of nano-Si, sintering, and HF etching showed multiple changes in the surface features. The surface roughness of Groups C, S, and N were 0.88 ± 0.07 µm, 1.26 ± 0.10 µm, and 1.69 ± 0.15 µm, respectively. The surface roughness of Group N was significantly higher than that of Groups C and S (P < .05). EDX analysis showed peaks that corresponded to silica (Si) after infiltration with colloidal Si that disappeared following acid etching. Infiltrating nano-Si increases the surface roughness of zirconia. The formation of retentive nanopores on the surface potentially improves the zirconia-resin cement bonding strengths. [ABSTRACT FROM AUTHOR]

Surface contaminants on customized implant abutments could trigger an inflammatory response in the peri-implant tissues. The aim of this randomized controlled study was to assess the radiographic bone changes around implants restored with customized, platform-switched abutments, with and without autoclave treatment, 12 months after definitive restoration. Dental implants were placed 1 mm subcrestally in 64 systemically healthy patients (mean age: 63.3 ± 10.0 years; 31 patients had a history of periodontitis) to replace single or multiple missing teeth. According to a randomization list, abutments were subjected to steam and autoclave sterilization (43 implants, test group) or steam cleaning alone (44 implants, control group). Periapical standardized radiographs were taken at implant placement, prosthetic abutment connection, and 12 months after definitive cement-retained restoration. All implants were clinically stable without any sign of infection at the 12-month follow-up. An average marginal bone loss of 0.25 ± 0.19 mm was found in the test group compared to 0.35 ± 0.23 mm in the control group (no statistically significant difference), while the percentage of bleeding sites was significantly higher in the control group (8.7% ± 13.1% vs 19.1% ± 19.8%; P = .035). Autoclave treatment of customized abutments seems to reduce the inflammatory response around subcrestally placed implants. [ABSTRACT FROM AUTHOR]

Purpose: To compare the effect of taper, length, angle, and number of vertical axial walls on the retentive strength of a cemented crown on a partially customized hybrid abutment in the esthetic zone. Materials and Methods: A total of 35 metal copings were used and divided into two groups. One group had 30 copings cemented to their corresponding 8-degree tapered abutment with lengths from 3 to 8 mm, increasing in 1-mm increments (5 copings per length). The other group had the remaining 5 copings and consisted of a standardized metal coping that matched a hexagonal abutment with 3-mm vertical axial walls and the sequential removal of 1, 2, and 3 contiguous vertical axial walls. Dislodgment tests were performed for all copings in both groups. Maximum retentive forces were measured in retentive strength (kgF), with a conversion factor of 9.807 N = 1 kgF. Results: At each tapered abutment length, the retentive strength increased proportionally and was significantly different, ranging from 31.67 ± 4.10 kgF to 67.68 ± 11.22 kgF (F [5,24] = 20.46, P < .001). An unmodified hexagonal abutment demonstrated the highest retentive strength (70.15 ± 12.97 kgF). The sequential removal of 1, 2, and 3 contiguous vertical axial walls of the hexagonal abutment resulted in retentive strength values of 59.89 ± 10.06 kgF, 57.01 ± 9.62 kgF, and 55.99 ± 9.35 kgF, respectively, with no significant difference (P > .05) in strength. Conclusions: A partially customized abutment with vertical axial walls on one side and a profile reduction on the opposite side can provide comparable retention to cemented copings at one-third the length and at one-sixth the surface area of an 8-mm abutment with an 8-degree taper. [ABSTRACT FROM AUTHOR]

Purpose: To assess the healing process of the extraction socket and the dimensional changes that occur after alveolar ridge preservation utilizing a polylactide-co-glycolide scaffold (PLGA). Materials and Methods: The present study involved the extraction of 28 teeth from 14 patients. The total number of sockets was 28, which were divided into two groups consisting of 14 test sockets and 14 control sockets. The study group (SG) was subjected to socket preservation with a PLGA scaffold while the control group (CG) was left for spontaneous healing. The dimensions were measured before and after operation at 1, 3, and 5 mm below the alveolar crest horizontally and the height of buccolingual bone vertically. Results: According to the histologic analyses, the PLGA scaffold was resorbed within 4 months. CBCT imaging revealed a decrease in the horizontal crest dimension at three distinct coronoapical levels in SG, measuring 2.05 ± 1.05 mm at -1 mm, 1.51 ± 0.89 mm at -3 mm, and 0.92 ± 0.7 mm at -5 mm. CG showed readings of 1.22 ± 1 at -1 mm, 0.92 ± 0.67 at -3 mm, and 0.73 ± 0.69 at -5 mm. In comparison to CG, SG showed a significant reduction in horizontal losses at -1 mm. Vertical crest dimensions decreased by 1.64 ± 1.11 mm for the buccal bone height and by 1.56 ± 1.08 mm for lingual bone height in SG; in CG, the buccal and lingual bone height had mean values of 2.08 ± 1.44 mm and 1.73 ± 1.27 mm, respectively. There was no statistically significant difference observed in the vertical losses between the groups. Conclusions: Following a period of 4 months, the PLGA scaffold was completely resorbed. Based on CBCT measurements, horizontal resorption was lower than CG at -1 mm coronally. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical and radiographic results of simultaneous implant placement using transcrestal sinus floor elevation (TSFE) with and without enamel matrix derivative (EMD) application. Materials and Methods: Twenty-four patients were randomly assigned into two groups: The EMD+TSFE group (n = 13 patients, 20 implants) received TSFE with EMD application, and the TSFE group (n = 11 patients, 20 implants) received TSFE without EMD application. The patients were recalled at 3 (T3) and 12 (T12) months postsurgery. The residual bone height (RBH), implant protrusion length (IPL), peri-implant sinus bone level (SBL), endo-sinus bone gain (ESBG), and implant stability (ISQ) were measured. Multivariate regressions were performed for the groups. Results: At T3, the ESBG was 3.72 ± 0.85 mm in the EMD+TSFE group and 3.10 ± 0.05 mm in the TSFE group, and there were statistically significant differences (P < .05). However, there were no statistically significant differences in ESBG at T12 between the groups (P > .05). ISQ values did not show a statistical difference between the groups at T1 and T3, but at T3 in the TSFE+EMD group, there was a statistical increase in the intragroup evaluation compared to the TSFE group. Conclusions: The use of EMD in TSFE procedures is effective in new bone formation at the apical part of the implant during the early healing period, but in the long term, no significant difference was shown between cases in which EMD was or was not used in terms of new bone formation and primary and secondary stabilization. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of sinus membrane stabilization (via suturing) and dental implant placement on the endo-sinus bone formation in lateral sinus elevations performed without grafting. Materials and Methods: Maxillary sinus elevation surgery using the lateral approach was performed bilaterally on 30 New Zealand white rabbits. The maxillary sinus areas were divided into control and test groups. In the control group, a titanium screw was placed after sinus membrane elevation; in the test group, the sinus membrane was sutured to the lateral walls, and a titanium screw was placed in the center of the alveolar crest. The subjects were sacrificed at 4 and 8 weeks. Then samples were collected, and a microcomputed tomography (micro-CT) analysis was performed. In addition, the volume of newly formed bone, percentage of osseointegration, sinus volume, residual bone height, and implant protrusion length were measured using micro-CT analysis. Results: The sinus volume, volume of newly formed bone, and percentage of osseointegration in the test group were significantly higher than in the control group at 4 weeks (P = .01, P = .04, P = .02, respectively). While the volume of newly formed bone was 17.1 ± 3.08 mm3 in the control group, it was 26.9 ± 14.26 mm3 in the test group at 4 weeks. The volume of newly formed bone significantly decreased from 26.9 ± 14.26 mm3 to 17 ± 3.66 mm3 at 8 weeks (P = .02). No significant difference in residual bone height was found at 4 and 8 weeks (P = .07). No significant difference in implant protrusion length was found between the control and test groups (P = .18). Protrusion length and new bone formation in the sinus showed a negative relationship (P = .01). Conclusions: Suturing the sinus membrane to the lateral sinus wall is an effective approach for increasing osseointegration, bone volume, and sinus volume in the short term. A slow-absorbing suture material can be used to maintain sinus and bone volumes in the long term. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate four decontamination strategies utilizing enzymatic agents available in most clinical settings to determine (1) the amount of biomaterial that can be removed in a group of previously used healing abutments (uHAs) and (2) the degree to which the decontaminated HAs are capable of inducing an inflammatory response in vitro compared to new HAs. Materials and Methods: In total, 50 HAs were collected following 2 to 4 weeks of intraoral use and distributed randomly into five test groups (groups A-E; n = 10 per group). Group A used enzymatic cleaner foam and an autoclave. Group B used an ultrasonic bath with enzymatic cleaner and an autoclave. Group C used a prophy jet, enzymatic cleaner foam, and an autoclave. Group D used a prophy jet, an ultrasonic bath with enzymatic cleaner, and an autoclave. Lastly, group E used a prophy jet and an autoclave. The control group consisted of 10 new and sterile HAs. Residual protein concentration was determined by a Micro BCA protein assay (Thermo Fisher Scientific), while HAs from each group were stained with Phloxine B and macroscopically examined for the presence of debris. To examine the inflammatory potential, human primary macrophages were exposed to HAs, and supernatant levels of nine cytokine and chemokine profiles were analyzed using a multiplex bead assay. Results: All test groups showed differences in the degree of visual decontamination compared to controls. Groups D and E displayed the most effective surface debris removal and reduced protein concentration, while group A was the least effective. However, compared to controls, all test groups showed high levels of inflammatory cytokine secretion via multiplex assay for up to 5 days. Conclusions: Our study found that decontamination of uHAs utilizing enzymatic cleaners failed to reestablish inert HA surfaces and prevent an inflammatory immune response in vitro. Clinicians should not reuse HAs even after attempts to decontaminate and sterilize HA surfaces. [ABSTRACT FROM AUTHOR]

Polyethylene oxide (PEO) holds significant importance in the field of batteries due to its high processability, intrinsic properties, and potential for high ionic conductivity. Achieving simulation at different scales is crucial for gaining a comprehensive understanding of its properties and thus improving them. In this context, we conducted a comparative study on the molecular physical structure, thermodynamic, and dynamic properties of PEO using three distinct coarse-grained (CG) procedures and all-atom (AA) simulations. The three CG simulation procedures involved modeling with MARTINI forcefield, SPICA forcefield, and an IBI derived potential from AA simulations. The AA simulation has been performed using the class 2 pcff+ forcefield. The ensuing simulated densities align significantly with the literature data, indicating the reliability of our approach. The solubility parameter from the AA simulation closely corresponds to literature reported values. MARTINI and SPICA yield almost similar solubility parameters, consistent with the similar density predicted by both the forcefields. Notably, SPICA forcefield closely reproduces the intermolecular structure of atomistic systems, as evidenced by radial distribution function (RDF). It also comprehensively replicates the distribution of radius of gyration (Rg) and the end-to-end distance (Re) of the atomistic samples. IBI ranks second to SPICA in emulating the structural properties of the atomistic systems, such as Rg, Re, and RDF. However, IBI falls short in accurately representing the solubility parameter of the amorphous PEO samples, while MARTINI does not provide an accurate representation of the structural properties of the systems. The use of SPICA forcefield results in enhanced dynamics of the systems in comparison with IBI and MARTINI. [ABSTRACT FROM AUTHOR]

Postural assessments of the lumbar spine lack valuable information about its properties. The purpose of this study was to assess neutral zone (NZ) characteristics via in vivo lumbar spine passive stiffness and relate NZ characteristics to standing lumbar lordosis. A comparison was made between those that develop low back pain during prolonged standing (pain developers) and those that do not (nonpain developers). Twenty-two participants with known pain status stood on level ground, and median lumbar lordosis angle was calculated. Participants were then placed in a near-frictionless jig to characterize their passive stiffness curve and location of their NZ. Overall, both pain developers and nonpain developers stood with a lumbar lordosis angle that was more extended than their NZ boundary. Pain developers stood slightly more extended (in comparison to nonpain developers) and had a lower moment corresponding to the location of their extension NZ boundary. Overall, in comparison to nonpain developers, pain developers displayed a lower moment corresponding to the location of their extension NZ boundary which could correspond to greater laxity in the lumbar spine. This may indicate why pain developers have a tendency to stand further beyond their NZ with greater muscle co-contraction. [ABSTRACT FROM AUTHOR]

The purposes of this study were to clarify the electromyography (EMG) of plantar flexors and to analyze the fascicle and tendon behaviors of the gastrocnemius medialis (GM) during running in the carbon-fiber plate embedded in thicker midsole racing shoes, such as the Nike ZoomX Vaporfly (VF) and traditional racing shoes (TRAD). We compared the fascicle and series elastic element behavior of the GM and EMG of the lower limb muscles during running (14 km/h, 45 s) in athletes wearing VF or TRAD. GM EMGs in the push-off phase were approximately 50% lower in athletes wearing VF than in TRAD. Although the series elastic element behavior and/or mean fascicle-shortening velocity during the entire stance phase were not significantly different between VF and TRAD, a significant difference was found in both the mean EMG and integral EMG of the GM during the push-off phase. EMG of the gastrocnemius lateralis (GL) during the first half of the push-off phase was significantly different between VF and TRAD. Present results suggest that VF facilitates running propulsion, resulting in a decrease in GM and GL EMGs at a given running velocity during the push-off phase, leading to a reduction in metabolic cost. [ABSTRACT FROM AUTHOR]

No studies have reported ground reaction force (GRF) profiles of the repeated depth jump (DJ) protocols commonly used to study exercise-induced muscle damage. Furthermore, while compression garments (CG) may accelerate recovery from exercise-induced muscle damage, any effects on the repeated bout effect are unknown. Therefore, we investigated the GRF profiles of 2 repeated bouts of damage-inducing DJs and the effects of wearing CG for recovery. Nonresistance-trained males randomly received CG (n = 9) or placebo (n = 8) for 72 hours recovery, following 20 × 20 m sprints and 10 × 10 DJs from 0.6 m. Exercise was repeated after 14 days. Using a 3-way (set × bout × group) design, changes in GRF were assessed with analysis of variance and statistical parametric mapping. Jump height, reactive strength, peak, and mean propulsive forces declined between sets (P <.001). Vertical stiffness, contact time, force at zero velocity, and propulsive duration increased (P <.05). According to statistical parametric mapping, braking (17%–25% of the movement) and propulsive forces (58%–81%) declined (P <.05). During the repeated bout, peak propulsive force and duration increased (P <.05), while mean propulsive force (P <.05) and GRF from 59% to 73% declined (P <.001). A repeated bout of DJs differed in propulsive GRF, without changes to the eccentric phase, or effects from CG. [ABSTRACT FROM AUTHOR]

Bike fitting aims to optimize riders' positions to improve their performance and reduce the risk of injury. To calculate joint angles, the location of the joint centers of the lower limbs needs to be identified. However, one of the greatest difficulties is the location of the hip joint center due to the frequent occlusion of the anterior superior iliac spine markers. Therefore, the objective of this study was to validate a biomechanical model adapted to cycling (modified pelvic model, MPM), based on the traditional pelvic model (TPM) with an additional lateral technical marker placed on the iliac crests. MPM was also compared with a widely used model in cycling, trochanter model (TM). Thirty-one recreational cyclists pedaled on a roller bike while the movement was captured with a 7-camera VICON system. The position of the hip joint center and knee angle were calculated and compared with the TPM continuously (along 10 pedaling cycles) and discreetly at 90° and 180° crank positions. No significant differences were found in the position of the hip joint center or in the knee flexion/extension angle between the TPM and the MPM. However, there are differences between TPM and TM (variations between 4.1° and 6.9° in favor of the TM at 90° and 180°; P <.001). Bland–Altman graphs comparing the models show an average difference or bias close to 0° (limits of agreement [0.2 to −8.5]) between TPM and MPM in both lower limbs and a mean difference of between −4° and −7° (limits of agreement [−0.6 to −13.2]) when comparing TPM and TM. Given the results, the new cycling pelvic model has proven to be valid compared with the TPM when performing bike fitting studies, with the advantage that the occluded markers are avoided. Despite its simplicity, the TM presents measurement errors that may be relevant when making diagnoses, which makes its usefulness questionable. [ABSTRACT FROM AUTHOR]

The aim of this systematic review, meta-analysis, and meta-regression was to examine the effects of virtual reality–based training on global cognition and executive function compared with conventional training or information-based treatment in older adults, regardless of cognitive level. A systematic literature search was conducted using four databases. A total of 31 randomized controlled trials were identified. Pooled effect sizes were calculated, the risk of bias was assessed, and evidence was graded. The primary analyses showed a small but statistically significant effect of virtual reality–based training compared with control on global cognition (Hedges' g 0.42, 95% confidence interval [0.17, 0.68], I2 = 70.1%, n = 876, 20 randomized controlled trials, low evidence) and executive function (Hedges' g 0.35, 95% confidence interval [0.06, 0.65], I2 = 68.4%, n = 810, 16 randomized controlled trials, very low evidence). Meta-regression yielded inconclusive results. Virtual reality–based training may be more effective than control in improving cognition in older adults; however, more high-quality studies are needed. [ABSTRACT FROM AUTHOR]

Manipulating the amount of muscle mass engaged during exercise can noninvasively inform the contribution of central cardiovascular and peripheral vascular-oxidative functions to endurance performance. To better understand the factors contributing to exercise limitation in older and younger individuals, exercise performance was assessed during single-leg and double-leg cycling. 16 older (67 ± 5 years) and 14 younger (35 ± 5 years) individuals performed a maximal exercise using single-leg and double-leg cycling. The ratio of single-leg to double-leg cycling power (RatioPower SL/DL) was compared between age groups. The association between fitness (peak oxygen consumption, peak power output, and physical activity levels) and RatioPower SL/DL was explored. The RatioPower SL/DL was greater in older compared with younger individuals (1.14 ± 0.11 vs. 1.06 ± 0.08, p =.041). The RatioPower SL/DL was correlated with peak oxygen consumption (r =.886, p <.001), peak power output relative to body mass (r =.854, p <.001), and levels of physical activity (r =.728, p =.003) in the younger but not older subgroup. Reducing the amount of muscle mass engaged during exercise improved exercise capacity to a greater extent in older versus younger population and may reflect a greater reduction in central cardiovascular function compared with peripheral vascular-oxidative function with aging. [ABSTRACT FROM AUTHOR]

The aim of this study was to quantify physical activity and sedentary behavior in older adults recovering from hip fracture and to identify groups based on movement patterns. In this cross-sectional cohort study, older adults (≥70 years) were included 3 months after surgery for proximal femoral fracture. Patients received an accelerometer for 7 days. Demographics and outcomes related to physical function, mobility, cognitive functions, quality of life, and hip fracture were assessed. In total, 43 patients with sufficient accelerometer wear time were included. Across all groups, participants engaged in very low levels of physical activity, spending an average of 11 hr/day in prolonged sedentary behavior. Based on the extracted components from a principal component analysis, three groups with substantial differences in levels of physical activity and sedentary behavior could be distinguished. [ABSTRACT FROM AUTHOR]

Back pain lifetime incidence is 60%–70%, while 12%–20% of older women have vertebral fractures (VFs), often with back pain. We aimed to provide objective evidence, currently lacking, regarding whether back pain and VFs affect physical activity (PA). We recruited 69 women with recent back pain (age 74.5 ± 5.4 years). Low- (0.5 < g < 1.0), medium- (1.0 ≤ g < 1.5), and high-impact (g ≥ 1.5) PA and walking time were measured (100 Hz for 7 days, hip-worn accelerometer). Linear mixed-effects models assessed associations between self-reported pain and PA, and group differences (VFs from spine radiographs/no-VF) in PA. Higher daily pain was associated with reduced low (β = −0.12, 95% confidence interval, [−0.22, −0.03], p =.013) and medium-impact PA (β = −0.11, 95% confidence interval, [−0.21, −0.01], p =.041), but not high-impact PA or walking time (p >.11). VFs were not associated with PA (all p >.2). Higher daily pain levels but not VFs were associated with reduced low- and medium-impact PA, which could increase sarcopenia and falls risk in older women with back pain. [ABSTRACT FROM AUTHOR]

As rates of obesity continue to rise, so does the impact of obesity on cognitive function. Engaging in physical activity is one pathway through which individuals can help maintain cognitive function. This study examined whether any link between exercise and cognitive function was associated with weight characteristics. Data from 6,012 participants in the Health and Retirement Study were used. The association between participation in light or moderate physical activity and better cognitive function was particularly strong for overweight or obese adults and less so for those who were normal weight. Overall, the findings suggested that while being physically active is associated with better cognitive function regardless of weight, the associations were stronger for individuals who were overweight/obese compared with those who were normal weight. Given the results were particularly pronounced for waist circumference (relative to body mass index), further research should be conducted to examine if individuals with greater abdominal adiposity may benefit most from staying active in terms of their cognitive function. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was 2-fold: (1) to examine the relationships between psychophysiological responses and locomotor demands with variations in technical performance during 2v2 and 4v4 conditioned games and (2) to compare psychophysiological and locomotor responses among players exhibiting higher and lower technical performance levels during the conditioned games. Methods: Twenty-four male youth soccer players (16.3 ± 0.8 y old) participating at the trained/developmental level underwent monitoring for psychophysiological responses (including heart rate, rating of perceived exertion, and visual analog scale), locomotor demands (such as distance covered), and technical performance variables (including successful and unsuccessful passes and shots, as well as lost balls) across 2v2 and 4v4 formats. These formats were applied 4 times within a single session and were replicated twice over 2 weeks. Results: Large correlations between the number of lost balls per minute and mean heart rate were found in both the 2v2 and 4v4 games (r =.586 and r =.665, respectively). Successful shots were inversely and largely correlated with mean heart rate (r = −.518) in 4v4 games. The number of interceptions per minute was inversely and significantly correlated with the visual analog scale in 2v2 and 4v4 games (r = −.455 and r = −.710, respectively). The frequency of lost balls was significantly higher among players who attained a higher mean heart rate (2v2: +42.9%, P =.031, d = −0.965; 4v4: +57.1%, P <.001, d = −2.072). Conclusions: Coaches should be aware that highly psychophysiologically demanding scenarios may significantly impair technical performance. Therefore, prioritizing technical performance by deliberately adjusting the intensity should be considered. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to cross-validate a recently proposed equation for the prediction of maximal oxygen uptake ( V ˙ O 2 max) in cycling exercise by using the average power output normalized by the body mass from a 5-minute time trial (RPO5-min) as the independent variable. Further, the study aimed to update the predictive equation using Bayesian informative prior distributions and meta-analysis. Methods: On different days, 49 male cyclists performed an incremental graded exercise test until exhaustion and a 5-minute time trial on a stationary cycle ergometer. We compared the actual V ˙ O 2 max with the predicted value obtained from the RPO5-min, using a modified Bayesian Bland–Altman agreement analysis. In addition, this study updated the data on the linear regression between V ˙ O 2 max and RPO5-min, by incorporating information from a previous study as a Bayesian informative prior distribution or via meta-analysis. Results: On average, the predicted V ˙ O 2 max using RPO5-min underestimated the actual V ˙ O 2 max by −6.6 mL·kg–1·min–1 (95% credible interval, −8.6 to −4.7 mL·kg–1·min–1). The lower and upper 95% limits of agreement were −17.2 (−22.7 to −12.3) and 3.8 (−1.0 to 9.5) mL·kg–1·min–1, respectively. When the current study's data were analyzed using the previously published data as a Bayesian informative prior distribution, the accuracy of predicting sample means was found to be better when compared with the data combined via meta-analyses. Conclusions: The proposed equation presented systematic bias in our sample, in which the prediction underestimated the actual V ˙ O 2 max. We provide an updated equation using the previous one as the prior distribution, which could be generalized to a greater audience of cyclists. [ABSTRACT FROM AUTHOR]

Background: Durability (ie, the ability to attenuate the decline in performance after accumulated work) has been identified as a performance determinant in elite cyclists. The aim of the present study was to compare durability in elite cyclists of various performance levels, particularly after high-intensity work, referred to as "high-intensity durability." Methods: Forty-nine (N = 49) male road cyclists were categorized as either under 23 years of age (U23) (N = 11), Pro Team (N = 13), or World Tour (N = 24). The participants' critical power (CP) was assessed during the preseason. Thereafter, the participants' maximum mean power (MMP) values were determined for efforts of different durations (from 5 s to 30 min) after different levels of accumulated work above CP (from 0 to 7.5 kJ·kg−1). Results: U23 cyclists showed a significant reduction of all relative MMP values for durations ≥1 minute after ≥5 kJ·kg−1 above CP compared with the "fresh" state (0 kJ·kg−1), whereas in Pro Team and World Tour cyclists, a significant reduction was not observed until 7.5 kJ·kg−1 above CP. In the "fresh" state, both Pro Team and particularly World Tour cyclists attained higher MMP values for efforts ≥10 minutes than U23 riders. However, more differences emerged with greater previous work levels, and indeed after 7.5 kJ·kg−1 above CP World Tour cyclists attained higher MMP values than both U23 and Pro Team cyclists for most efforts (≥30 s). Conclusion: Pro Team and particularly World Tour cyclists tolerate greater levels of accumulated work at high intensity, which might support the importance of high-intensity durability for performance. [ABSTRACT FROM AUTHOR]