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Despite the prognostic effect of physical activity, acute bouts of high-volume endurance exercise can induce cardiac stress and postexercise hypercoagulation associated with increased thrombotic risk. The aim of this study was to explore the effect of high-volume endurance exercise on coagulation and thrombotic activity in recreational cyclists. Thirty-four recreational cyclists completed 4.8 ± 0.3 h of cycling at 45 ± 5% of maximal power output on a bicycle ergometer. Intravenous blood samples were collected preexercise, immediately postexercise, 24 and 48 h postexercise, and analyzed for brain natriuretic peptide (BNP), cardiac troponin (cTn), C-reactive protein (CRP), D-dimer, thrombin-antithrombin (TAT) complex, tissue factor (TF), tissue factor pathway inhibitor (TFPI), and TF-to-TFPI ratio (TF:TFPI). An increase in cTn was observed postexercise (P < 0.001). CRP concentrations were increased at 24 and 48 h postexercise compared with preexercise concentrations (P ≤ 0.001). TF was elevated at 24 h postexercise (P < 0.031) and TFPI was higher immediately postexercise (P < 0.044) compared with all other time points. TF:TFPI was increased at 24 and 48 h postexercise compared with preexercise (P < 0.025). TAT complex was reduced at 48 h postexercise compared with preexercise (P = 0.015), D-dimer was higher immediately postexercise compared with all other time points (P ≤ 0.013). No significant differences were observed in BNP (P > 0.05). High-volume endurance cycling induced markers of cardiac stress among recreational cyclists. However, plasma coagulation and fibrinolytic activity suggest no increase in thrombotic risk after high-volume endurance exercise. NEW & NOTEWORTHY: In this study, a high-volume endurance exercise protocol induced markers of cardiac stress and altered plasma coagulation and fibrinolytic activity for up to 48 h in recreationally active cyclists. However, analysis of coagulation biomarkers indicates no increase in thrombotic risk when appropriate hydration and rest protocols are implemented. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine if residual neuromuscular fatigue influenced subsequent match and training activity in professional women's basketball. Prior to matches and training sessions throughout a season, players performed countermovement jumps while wearing a magnetic, angular rate and gravity (acceleration) sensor on their upper back. Flight time to contraction time ratio was used to determine neuromuscular performance and to identify neuromuscular fatigue. Average session intensity and volume, the proportion of live time spent in different intensity bands (matches), and absolute and relative time spent in different intensity bands (training) were quantified using accelerometry. Residual neuromuscular fatigue was deemed to be present when the decrement in neuromuscular performance relative to pre-season baseline was greater than the smallest worthwhile change. Players displayed residual neuromuscular fatigue before 16% of matches and 33% of training sessions. When players were fatigued prior to matches, the proportion of live time undertaking supramaximal activity was 5.7% less (p = 0.02) and moderate-vigorous activity was 3.7% more than when not fatigued (p = 0.02). When fatigued prior to training, the players displayed a 2.6% decrement in average intensity (p = 0.02), 2.8% decrement in absolute (p = 0.01) and 5.0% decrement in relative (p = 0.01) maximal activity, as well as 13.3% decrement in absolute (p < 0.01) and 6.8% decrement in relative (p < 0.01) supramaximal activity when compared to not being fatigued. These findings suggest that residual neuromuscular fatigue influences players' ability to perform supramaximal activity, which highlights the importance of monitoring neuromuscular performance throughout a professional season. Highlights Residual neuromuscular fatigue can influence the amount of supramaximal activity players perform in a subsequent training session or match. Practices should be implemented to minimise residual neuromuscular fatigue carried into matches while maintaining a sufficient training volume to elicit physiological adaptations. MARG sensors can be used as an affordable and time-efficient tool for regularly monitoring countermovement jump-derived neuromuscular fatigue. [ABSTRACT FROM AUTHOR]

Context: Accelerometer peak impact accelerations are being used to measure player physical demands in contact sports. However, their accuracy to do so has not been ascertained. Purpose: To compare peak-impact-acceleration data from an accelerometer contained in a wearable tracking device with a 3-dimensional motion-analysis (MA) system during tackling and bumping. Methods: Twenty-five semielite rugby athletes wore a tracking device containing a 100-Hz triaxial accelerometer (MinimaxX S4, Catapult Innovations, Australia). A single retroreflective marker was attached to the device, with its position recorded by a 12-camera MA system during 3 physical-collision tasks (tackle bag, bump pad, and tackle drill; N = 625). The accuracy, effect size, agreement, precision, and relative errors for each comparison were obtained as measures of accelerometer validity. Results: Physical-collision peak impact accelerations recorded by the accelerometer overestimated (mean bias 0.60 g) those recorded by the MA system (P < .01). Filtering the raw data at a 20-Hz cutoff improved the accelerometer's relationship with MA data (mean bias 0.01 g; P > .05). When considering the data in 9 magnitude bands, the strongest relationship with the MA system was found in the 3.0-g or less band, and the precision of the accelerometer tended to reduce as the magnitude of impact acceleration increased. Of the 3 movements performed, the tackle-bag task displayed the greatest validity with MA. Conclusions: The findings indicate that the MinimaxX S4 accelerometer can accurately measure physical-collision peak impact accelerations when data are filtered at a 20-Hz cutoff frequency. As a result, accelerometers may be useful to measure physical collisions in contact sports. [ABSTRACT FROM AUTHOR]

The aim of this review was to investigate associations between physical fitness characteristics, on-court activity, individual performance, and team success in basketball. Following an electronic search of three databases, 27 articles investigating associations between physical fitness characteristics, on-court activity, measures of individual performance and team success were reviewed. Review of the literature found that better change-of-direction speed was typically associated with more individual (match statistics, representative team selection) and team (ranking) success across multiple age groups and competition levels. Aerobic capacity, linear speed and jump height were typically associated with more individual success (match statistics, representative team selection, player rating) in youth players, but not in senior players. Therefore, current data suggest that improving change-of-direction speed might be beneficial for all basketball performance, while improving aerobic capacity, speed and jump height might be beneficial for youth players only. Additional findings from this review include that: aerobic capacity appears to be important for maintaining highintensity running volumes and active movements; change-of-direction speed might facilitate performing high volumes of lateral movement and total, moderate and high-intensity running; and linear speed might be important for performing high volumes of running in all speed zones. Associations between on-court activity (e.g., running volumes) and individual and team success (e.g., competition level, match outcome) were conflicting between studies, potentially due to differences between demographics or competitions, or technical and tactical factors. These findings can guide training prescription for basketball players, with more focus on the physical performance characteristics most often linked to success in their age group, and the physical performance characteristics that enable greater volumes of on-court activity. Further investigation is required to evaluate associations between on-court activity and success. [ABSTRACT FROM AUTHOR]

This study assessed the criterion validity of a magnetic, angular rate, and gravity (MARG) sensor to measure countermovement jump (CMJ) performance metrics, including CMJ kinetics before take-off, in elite basketballers. Fifty-four basketballers performed 2 CMJs on a force platform with data simultaneously recorded by a MARG sensor located centrally on the player’s back. Vertical accelerations recorded from the MARG sensor were expressed relative to the direction of gravity. Jumps were analyzed by a blinded assessor and the best jump according to the force platform was used for comparison. Pearson correlation coefficients (r) and mean bias with 95% ratio limits of agreement (95% RLOA) were calculated between the MARG sensor and the force platform for jumps performed with correct technique (n = 44). The mean bias for all CMJ metrics was less than 3%. Ninety-five percent RLOA between MARG- and force platform–derived flight time and jump height were 1 ± 7% and 1 ± 15%, respectively. For CMJ performance metrics before takeoff, impulse displayed less random error (95% RLOA: 1 ± 13%) when compared with mean concentric power and time to maximum force displayed (95% RLOA: 0 ± 29% and 1 ± 34%, respectively). Correlations between MARG and force platform were significant for all CMJ metrics and ranged from large for jump height (r = 0.65) to nearly perfect for mean concentric power (r = 0.95). Strong relationships, low mean bias, and low random error between MARG and force platform suggest that MARG sensors can provide a practical and inexpensive tool to measure impulse and flight time–derived CMJ performance metrics. [ABSTRACT FROM AUTHOR]

The purpose of this study was to validate peak acceleration data from an accelerometer contained within a wearable tracking device while walking, jogging and running. Thirty-nine participants walked, jogged and ran on a treadmill while 10 peak accelerations per movement were obtained (n = 390). A single triaxial accelerometer measured resultant acceleration during all movements. To provide a criterion measure of acceleration, a 12-camera motion analysis (MA) system tracked the position of a retro-reflective marker affixed to the wearable tracking device. Peak raw acceleration recorded by the accelerometer significantly overestimated peak MA acceleration (P < 0.01). Filtering accelerometer data improved the relationship with the MA system (P < 0.01). However, only the 10 Hz and 8 Hz cut-off frequencies significantly reduced the errors found. The walk movement demonstrated the highest accuracy, agreement and precision and the lowest relative errors. Linear increases in error were observed for jog compared with walk and for run compared to both other movements. As the magnitude of acceleration increased, the strength of the relationship between the accelerometer and the criterion measure decreased. These results indicate that filtered accelerometer data provide an acceptable means of assessing peak accelerations, in particular for walking and jogging. [ABSTRACT FROM AUTHOR]

The floor apparatus is associated with the highest rate of injury for male and female gymnasts in training and competition. This study aims to determine the magnitude of the upper and lower body impact loading when performing foundation floor tumbling skills and sequences. Fourteen sub‐elite artistic gymnasts (male, n = 9; female, n = 5) performed eight tumbling skills and sequences while wearing four inertial measurement units (IMU; upper back, lower back, forearm, and tibia). The peak resultant acceleration (PRA) during all ground contacts was calculated. The forearm and upper back PRA were analyzed for hand contacts, while the lower back and tibia PRA were analyzed for foot contacts. Descriptive statistics (median and inter‐quartile range), Wilcoxon signed‐rank tests and Friedman's ANOVA were calculated between IMU positions and gymnastics skills. Distal IMUs (forearm and tibia) recorded significantly higher loading than proximal IMUs (upper and lower back) for all ground contacts. Proximal IMUs experienced dampening due to shock attenuation properties of the human body, as these positions are located further away from the impact site. Additionally, some foundation skills exposed gymnasts to higher loading when the skill was performed separately, while other skills exposed gymnasts to higher loading when the skill was performed in a tumbling sequence. Training foundation skills separately and as a part of a tumbling sequence exposes the upper and lower body structures to high levels of impact loading. These results can be used by coaches to help in the design of safe training programs. Highlights: Distal segments (forearm and tibia) experienced significantly higher magnitudes of impact loading than the proximal areas (upper and lower back) during foundation gymnastics skills, most likely due to the shock attenuation properties of the human body when absorbing ground impacts.During the round‐off skill, gymnasts experienced greater lower back impact loading upon landing when performing the skill separately, but experienced greater upper back loading during the hand contact phase when performing the skill as part of a sequence (i.e., round‐off to backwards handspring, and round‐off, backwards handspring to backwards somersault).Impact loading differed between skills performed separately and skills that were performed within a tumbling sequence. Therefore, the loading experienced on the body was different due to the context in which the skill was performed (i.e., having to connect another skill afterward).Skill sequences should be considered as distinct or individual skills, rather than a combination of foundation skills, to better address the observed differences when prescribing and monitoring training loads. [ABSTRACT FROM AUTHOR]