Recovery kinetics following sprint training: resisted versus unresisted sprints.

PURPOSE: To determine the recovery kinetics of performance and exercise-induced muscle damage following different sprint-training protocols. METHODS: In a crossover design, ten male and female athletes (20.6 ± 2.4 years) performed 2 × (3 × 20 m: 2 min rest) and 1× (3 × 30 m: 3 min rest) of: (a) unresisted sprints (UST), (b) resisted sprints with 10% of body mass (BM) load (RST10), (c) resisted sprints with 20% BM load (RST20), against a control trial (no-training). RESULTS: Blood lactate (mmol/L) increased post-training versus pre-training in all sprint-training trials (6.7 ± 2.4 vs 1.2 ± 0.2, 5.6 ± 2.4 vs 1.3 ± 0.3, 7.3 ± 2.7 vs 1.2 ± 0.3, in UST, RST10, RST20, respectively), as did creatine kinase (U/L) 24 h, 48 h and 72 h post-training (UST: 251 ± 173, 238 ± 154, 209 ± 115 vs 155 ± 9, RST10: 252 ± 134, 240 ± 83, 218 ± 103 vs 164 ± 106; RST20: 237 ± 133, 323 ± 303, 262 ± 184 vs 179 ± 106, respectively). DOMS of knee-extensors (KE) and knee-flexors (KF) increased post-training up to 72 h in all sprint-training trials versus pre-training (ranging from 1.6 ± 1.3 to 3.8 ± 2.8 vs 1.0 ± 0, respectively). Eccentric torque (N m) of the KE of the non-dominant limb, decreased 24 h post-training versus pre-training in all sprint-training trials (UST: 249 ± 49 vs 266 ± 54; RST10: 229 ± 52 vs 273 ± 72; RST20: 253 ± 6 vs 262 ± 56), as did that of the KF of the dominant limb (UST: 135 ± 29 vs 144 ± 26; RST10: 130 ± 29 vs 140 ± 25; RST20: 139 ± 33 vs 142 ± 26). 10-m sprint-time (s) increased 48 h post-training versus pre-training (1.81 ± 0.15 vs 1.77 ± 0.11), and 30-m sprint-time increased 24 h, 48 h, 72 h post-training versus pre-training (4.35 ± 0.36, 4.40 ± 0.44, 4.33 ± 0.41 vs 4.21 ± 0.34, respectively), only in RST20. CONCLUSIONS: Unresisted and resisted sprint-training induces prolonged reduction of muscle strength (24 h), and sprinting performance (72 h), associated with prolonged increase of DOMS and CK (72 h).

Recovery kinetics following eccentric exercise is volume-dependent.

The present study compared the effect of 75 vs 150 vs 300 intensity-matched eccentric contractions on muscle damage and performance recovery kinetics. Ten healthy males participated in a randomized, cross-over study consisted of 4 experimental trials (ECC75, ECC150, ECC300 and Control - no exercise) with a 4-week washout period in-between. Performance and muscle damage, inflammatory and oxidative stress markers were evaluated at baseline, post-exercise, 24, 48 and 192 hours following each exercise protocol. Concentric and eccentric peak torque decreased similarly in ECC150 and ECC300 during the first 48 h of recovery (p < 0.05) but remained unaffected in ECC75. Countermovement jump indices decreased post-exercise and at 24 h in ECC150 and ECC300, with ECC300 inducing a more pronounced reduction (p < 0.05). Creatine kinase increased until 48 h of recovery in all trials and remained elevated up to 192 h only in ECC300 (p < 0.05). Delayed onset of muscle soreness increased, and knee-joint range of motion decreased in a volume-dependent manner during the first 48 h (p < 0.05). Likewise, a volume-dependent decline of glutathione and a rise of protein carbonyls was observed during the first 48 h of recovery (p < 0.05). Collectively, our results indicate that muscle damage and performance recovery following eccentric exercise is volume dependent, at least in lower limbs.

The Effects of a Single Session of a Rhythmic Movement Program on Selected Biopsychological Parameters in PD Patients: A Methodological Approach.

The aim of the present study is to examine the acute effects of a specially designed musicokinetic (MSK) program for patients with Parkinson's disease (PD) on (a) anxiety levels, (b) select kinematic and kinetic parameters, and (c) frontal cortex hemodynamic responses, during gait initiation and steady-state walking. Methods: This is a blind cross-over randomized control trial (RCT) in which 13 volunteers with PD will attend a 45 min MSK program under the following conditions: (a) a synchronous learning format and (b) an asynchronous remote video-based format. Changes in gait biomechanics and frontal cortex hemodynamic responses will be examined using a 10-camera 3D motion analysis (Vicon T-series, Oxford, UK), and a functional near-infrared spectroscopy (f-NIRS-Portalite, Artinis NL) system, respectively, while anxiety levels will be evaluated using the Hamilton Anxiety Rating Scale. Expected results: Guided by the rules of music, where periodicity is distinct, our specially designed MSK program may eventually be beneficial in improving motor difficulties and, hence, reducing anxiety. The combined implementation of f-NIRS in parallel with 3D gait analysis has yet to be evaluated in Parkinsonian patients following a MSK intervention. It is expected that the aforementioned intervention, through better rhythmicity, may improve the automatization of motor control, gait kinematics, and kinetics-supported by decreased frontal cortex hemodynamic activity-which may be linked to reduced anxiety levels.

The Effects of Spirulina Supplementation on Redox Status and Performance Following a Muscle Damaging Protocol.

Spirulina plantensis is a popular supplement which has been shown to have antioxidant and performance enhancing properties. The purpose of this study was to evaluate the effects of spirulina supplementation on (a) redox status (b) muscle performance and (c) muscle damage following an eccentric bout of exercise that would induce muscle damage. Twenty-four healthy, recreationally trained males participated in the study and were randomly separated into two groups: a spirulina supplementation (6 g per day) and a placebo group. Both groups performed an eccentric bout of exercise consisting of 5 sets and 15 maximum reps per set. Blood was collected at 24, 48, 72 and 96 h after the bout and total antioxidant capacity (TAC) and protein carbonyls (PC) were assessed in plasma. Delayed onset muscle soreness (DOMS) was also assessed at the same aforementioned time points. Eccentric peak torque (EPT) was evaluated immediately after exercise, as well as at 24, 48, 72 and 96 h post exercise. Redox status indices (TAC and PC) did not change significantly at any time point post exercise. DOMS increased significantly 24 h post exercise and remained elevated until 72 h and 96 h post exercise for the placebo and spirulina group, respectively. EPT decreased significantly and immediately post exercise and remained significantly lower compared to baseline until 72 h post exercise. No significant differences between groups were found for DOMS and EPT. These results indicate that spirulina supplementation following a muscle damaging protocol does not confer beneficial effects on redox status, muscle performance or damage.

Upper-Body Posture in Adolescent Pianists: A Cross-Sectional Study.

AIMS: Although the significance of upper-body posture in relation to piano performance has often been highlighted, the role of experience remains unclear. The aim of this study was to examine selected upper body posture parameters in adolescent piano students of different performance level (beginners vs advanced). METHODS: Thirteen (13) adolescent piano students (14.7±0.5 yrs; 7 beginners and 6 advanced) volunteered. They all performed two specific major scales (G-major and E-major) in five octaves in two predetermined different tempi (slow and fast). An upper body biomechanical model consisting of 27 reflective markers was applied on specific bony landmarks. A 10-T camera Vicon system running Nexus 2 was employed to capture upper body motion--a) sway of the trunk in relation to the instrument, b) finger/hand sway over the keyboard, c) overall hand movement, and d) spinal angles--at selected moments of four different performances. RESULTS: Beginners demonstrated more trunk sway than their advanced counterparts (p<0.05), more finger/hand sway (p<0.05), more overall hand movement (p<0.05), and more flexed spinal angles at the start of their performance (p<0.05). Most of these differences appeared in the G-fast performances, whereas the G-slow equivalents revealed no differences. CONCLUSION: Less-experienced piano players are characterized by more movement in their trunk posture and more upper limb activity than their more advanced colleagues. Future research should examine whether interventional programs designed to alter upper-body posture would have beneficial effects in piano performance.

Variable, but not free-weight, resistance back squat exercise potentiates jump performance following a comprehensive task-specific warm-up.

Studies examining acute, high-speed movement performance enhancement following intense muscular contractions (frequently called "post-activation potentiation"; PAP) often impose a limited warm-up, compromizing external validity. In the present study, the effects on countermovement vertical jump (CMJ) performance of back squat exercises performed with or without elastic bands during warm-up were compared. After familiarization, fifteen active men visited the laboratory on two occasions under randomized, counterbalanced experimental squat warm-up conditions: (a) free-weight resistance (FWR) and (b) variable resistance (VR). After completing a comprehensive task-specific warm-up, three maximal CMJs were performed followed by three back squat repetitions completed at 85% of 1-RM using either FWR or VR Three CMJs were then performed 30 seconds, 4 minutes, 8 minutes, and 12 minutes later. During CMJ trials, hip, knee, and ankle joint kinematics, ground reaction force data and vastus medialis, vastus lateralis, and gluteus maximus electromyograms (EMG) were recorded simultaneously using 3D motion analysis, force platform, and EMG techniques, respectively. No change in any variable occurred after FWR (P > 0.05). Significant increases (P < 0.05) were detected at all time points following VR in CMJ height (5.3%-6.5%), peak power (4.4%-5.9%), rate of force development (12.9%-19.1%), peak concentric knee angular velocity (3.1%-4.1%), and mean concentric vastus lateralis EMG activity (27.5%-33.4%). The lack of effect of the free-weight conditioning contractions suggests that the comprehensive task-specific warm-up routine mitigated any further performance augmentation. However, the improved CMJ performance following the use of elastic bands is indicative that specific alterations in force-time properties of warm-up exercises may further improve performance.

Similar femoral growth and deformity with one screw versus two smooth pins for slipped capital femoral epiphysis.

PURPOSE: To compare longitudinal growth and cam deformity of the proximal femur after treatment for slipped capital femoral epiphysis (SCFE) with one screw versus two smooth pins. METHODS: We studied 43 patients (29 males, 14 females; mean age, 12.1 years; range, 9.5-14 years) with idiopathic unilateral SCFE treated with in situ fixation with one cannulated screw (group A, n = 23) or two smooth pins (group B, n = 20). Anteroposterior and frog-leg radiographs of the pelvis were evaluated for each patient at initial presentation, post-operatively and at physeal closure. Longitudinal growth was evaluated using the femoral neck length (FNL), the caput-collum-diaphyseal (CCD) angle, and the articulo-trochanteric distance (ATD). Cam deformity was assessed using the anterior offset α-angle and the head-neck offset ratio (HNOR). The mean follow-up was 5.1 years (range, 4-7 years). RESULTS: Postoperatively, the mean CCD angle was 138.3°, the mean α-angle was 66.1° and the mean HNOR was - 0.030. At physeal closure, mean CCD angle significantly decreased to 133.6°, mean α-angle significantly reduced to 52.1°, and mean HNOR significantly improved to + 0.039. CCD, FNL, ATD, α-angle, and HNOR were not different between groups. CONCLUSIONS: One screw or two smooth pins result in similar longitudinal growth and deformity of the proximal femur after SCFE. The femoral head-neck junction remarkably improves until physeal closure; however, residual cam deformity is not avoided after in situ pinning. The complication rate with smooth pins is higher.

Validation and cross-cultural adaptation of Greek version of Achilles tendon Total Rupture Score.

BACKGROUND: The purpose of this study was the translation, cross-cultural adaptation and validation of the Achilles Tendon Total Rupture Score (ATRS) in Greek population. METHODS: The translation and cross-cultural adaptation of the original version of ATRS in Greek language was performed according to the methodology described by Beaton et al. Validation and test-retest reliability were evaluated in forty-six patients, treated surgically for acute Achilles tendon rupture. Validity was evaluated by correlation of total and all subscale scores of Greek version of Manchester Foot Pain and Disability Index (MFPDI). Test-retest reliability evaluated with interclass correlation coefficient and Crombach's α coefficient was used for internal consistency. RESULTS: The internal consistency (α=0.96) and test-retest reliability (ICC=0.97) were excellent. There were no ceiling and floor effects during test-retest assessment. The Greek version of ATRS showed strong correlation with all subscales and overall score of MFPDI (pain subscale: R=-0.954, p<0.01, function subscale: R=-0.811, p<0.01, appearance subscale: R=-0.763, p<0.01, overall: R=-0.914, p<0.01). CONCLUSIONS: Greek version of ATRS was successfully adapted in Greek population and it appears to be a valid and reliable instrument to evaluate outcomes in Greek speaking patients after Achilles tendon rupture. LEVEL OF EVIDENCE: Level III.

Dynamic Effect of Quadriceps Muscle Activation on Anterior Tibial Translation After Single-Bundle and Double-Bundle Anterior Cruciate Ligament Reconstruction.

PURPOSE: To examine differences in anterior tibial translation in 3 groups: single-bundle anterior cruciate ligament (ACL)-reconstructed, double-bundle ACL-reconstructed, and ACL-intact knees under gradual dynamic quadriceps muscle activation. METHODS: Thirty male patients underwent successful single-bundle (n = 15) and double-bundle (n = 15) ACL reconstructions; 15 healthy controls were included in the study. Anterior tibial translation was assessed at 30° of knee flexion in the resting position (0% quadriceps activation) and under 50% and 100% of maximum quadriceps concentric contraction using an isokinetic dynamometer with the KT-2000 arthrometer securely attached to the participants' knees. RESULTS: The 2 ACL-reconstructed groups were similar regarding International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Score (KOOS), Tegner, and Lysholm scores and preliminary isokinetic evaluation (P = .38). Quadriceps activation significantly affected anterior tibial translation (P = .001, α = 0.98). In all 3 study groups, anterior tibial translation was significantly higher under 100% quadriceps activation compared with 0% contraction (P = .01) and 50% quadriceps activation (P = .047). There were no between-group differences in anterior tibial translation with 0%, 50%, or 100% quadriceps activation (P = .46). CONCLUSIONS: Under quadriceps muscle activation, anteroposterior knee laxity in ACL-intact and ACL-reconstructed knees is gradually increased. Single-bundle and double-bundle ACL-reconstructed knees show a similar increase in anterior tibial translation under gradual quadriceps contraction. When comparing different ACL reconstruction techniques in the experimental setting, dynamic, in addition to static, testing is advised to reach a comprehensive assessment of anteroposterior knee stability. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Comparison of functional gains after arthroscopic rotator cuff repair in patients over 70 years of age versus patients under 50 years of age: a prospective multicenter study.

PURPOSE: To assess rotator cuff rupture characteristics and evaluate healing and the functional outcome after arthroscopic repair in patients older than 70 years versus patients younger than 50 years. METHODS: We conducted a multicenter, prospective, comparative study of 40 patients younger than 50 years (group A) and 40 patients older than 70 years (group B) treated with arthroscopic rotator cuff repair. Patients older than 70 years were operated on only if symptoms persisted after 6 months of conservative treatment, whereas patients younger than 50 years were operated on regardless of any persistent symptoms. Imaging consisted of preoperative magnetic resonance imaging and postoperative ultrasound. Preoperative and postoperative function was evaluated with Constant and modified Constant scores. Patient satisfaction was also assessed. The evaluations were performed at least 1 year postoperatively. RESULTS: No patient was lost to follow-up. The incidence of both supraspinatus and infraspinatus tears was greater in group B. Greater retraction in the frontal plane and greater fatty infiltration were observed in group B. The Constant score was significantly improved in both groups (51 ± 12.32 preoperatively v 77.18 ± 11.02 postoperatively in group A and 48.8 ± 10.97 preoperatively v 74.6 ± 12.02 postoperatively in group B, P < .05). The improvement was similar in both groups. The modified Constant score was also significantly improved in both groups (57.48 ± 18.23 preoperatively v 81.35 ± 19.75 postoperatively in group A and 63.09 ± 14.96 preoperatively v 95.62 ± 17.61 postoperatively in group B, P < .05). The improvement was greater for group B (P < .05). Partial rerupture of the rotator cuff occurred in 2 cases in group A and 5 cases in group B. Complete rerupture was observed in 2 patients in group B. In group A, 29 patients (72.5%) were very satisfied, 8 (20%) were satisfied, and 3 (7.5%) were less satisfied. In group B, 33 patients (82.5%) were very satisfied, 6 (15%) were satisfied, and only 1 (2.5%) was less satisfied. CONCLUSIONS: Rotator cuff tears are characterized by greater retraction in the frontal plane and greater fatty infiltration in patients older than 70 years compared with patients younger than 50 years. After arthroscopic repair, healing is greater for patients younger than 50 years. Functional gain is at least equal between the 2 groups. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Development and validation of a questionnaire (FASH--Functional Assessment Scale for Acute Hamstring Injuries): to measure the severity and impact of symptoms on function and sports ability in patients with acute hamstring injuries.

OBJECTIVE: To develop a condition-specific patient-reported outcome measure, the Functional Assessment Scale for Acute Hamstring Injuries (FASH), de novo in three languages, following distinct and rigorous methodology for content generation, analysis and validation and to assess its psychometric properties. BACKGROUND: To our knowledge, there is no patient-reported functional scale specific for acute hamstring injuries. METHODS: The development of the scale followed specific guidelines, as well as de novo construction in three languages (Greek, English and German). Item generation was accomplished by selecting three different sources of items: literature review, focus group and key informant interviews. Content analysis was conducted by an expert committee. The 21 items selected as appropriate were tested through a structured content analytic method and item-content validity coefficient, and 10 were retained for the FASH. The validation and assessment of its psychometric properties followed theConsensus-based Standards for the selection of health status Measurement Instruments (COSMIN) recommendations to ensure quality, in a convenience sample of 140 participants. RESULTS: The face validity was adequate and tested by expert committees, authors and participants. Content validity was characterised as well addressed and conducted independently by experts and through specific content validation procedures. The dimensionality analysis indicated a one-factor solution explaining the 95.8% of total variance. Known group validity was demonstrated by significant differences between patients and controls (p<0.001). The FASH exhibited very good test-retest reliability (intraclass correlation coefficient=0.9, p<0.001), internal consistency (α=0.98) and responsiveness (3.81 and 5.23 using baseline and pooled SD, respectively; standardised response mean (SRD)=4.68). CONCLUSION: This study provides initial evidence for psychometric properties of the first scale assessing hamstring injuries.

Influence of variable resistance loading on subsequent free weight maximal back squat performance.

The purpose of the study was to determine the potentiating effects of variable resistance (VR) exercise during a warm-up on subsequent free-weight resistance (FWR) maximal squat performance. In the first session, 16 recreationally active men (age = 26.0 ± 7.8 years; height = 1.7 ± 0.2 m; mass = 82.6 ± 12.7 kg) were familiarized with the experimental protocols and tested for 1 repetition maximum (1RM) squat lift. The subjects then visited the laboratory on 2 further occasions under either control or experimental conditions. During these conditions, 2 sets of 3 repetitions of either FWR (control) or VR (experimental) squat lifts at 85% of 1RM were performed; during the experimental condition, 35% of the load was generated from band tension. After a 5-minute rest, 1RM, 3D knee joint kinematics, and vastus medialis, vastus lateralis, rectus femoris, and semitendinosus electromyogram (EMG) signals were recorded simultaneously. No subject increased 1RM after FWR, however, 13 of 16 (81%) subjects increased 1RM after VR (mean = 7.7%; p < 0.01). Lower peak and mean eccentric (16-19%; p ≤ 0.05) and concentric (12-21%; p ≤ 0.05) knee angular velocities were observed during the 1RM following VR when compared with FWR, however, no differences in knee flexion angle (1.8°; p > 0.05) or EMG amplitudes (mean = 5.9%; p > 0.05) occurred. Preconditioning using VR significantly increased 1RM without detectable changes in knee extensor muscle activity or knee flexion angle, although eccentric and concentric velocities were reduced. Thus, VR seems to potentiate the neuromuscular system to enhance subsequent maximal lifting performance. Athletes could thus use VR during warm-up routines to maximize squat performance.

Test-retest reliability of handgrip strength measurement using a hydraulic hand dynamometer in patients with cervical radiculopathy.

OBJECTIVE: The purpose of this study was to evaluate the test-retest reliability of handgrip strength measurement using a hydraulic hand dynamometer in patients with cervical radiculopathy (CR). METHODS: A convenience sample of 19 participants (14 men and 5 women; mean ± SD age, 50.5 ± 12 years) with CR was measured using a Jamar hydraulic hand dynamometer by the same rater on 2 different testing sessions with an interval of 7 days between sessions. Data collection procedures followed standardized grip strength testing guidelines established by the American Society of Hand Therapists. During the repeated measures, patients were advised to rest their upper limb in the standardized arm position and encouraged to exert 3 maximum gripping efforts. The mean value of the 3 efforts (measured in kilogram force [Kgf]) was used for data analysis. The intraclass correlation coefficient, SEM, and the Bland-Altman plot were used to estimate test-retest reliability and measurement precision. RESULTS: Grip strength measurement in CR demonstrated an intraclass correlation coefficient of 0.976, suggesting excellent test-retest reliability. The small SEM in both testing sessions (SEM1, 2.41 Kgf; SEM2, 2.51 Kgf) as well as the narrow width of the 95% limits of agreements (95% limits of agreement, -4.9 to 4.4 Kgf) in the Bland-Altman plot reflected precise measurements of grip strength in both occasions. CONCLUSIONS: Excellent test-retest reliability for grip strength measurement was measured in patients with CR, demonstrating that a hydraulic hand dynamometer could be used as an outcome measure for these patients.

Are Surface Electromyography Parameters Indicative of Post-Activation Potentiation/Post-Activation Performance Enhancement, in Terms of Twitch Potentiation and Voluntary Performance? A Systematic Review.

The aim was to identify if surface electromyography (sEMG) parameters are indicative of post-activation potentiation (PAP)/post-activation performance enhancement (PAPE), in terms of twitch potentiation and voluntary performance. Three databases were used in April 2024, with the following inclusion criteria: (a) original research, assessed in healthy human adults, and (b) sEMG parameters were measured. The exclusion criteria were (a) studies with no PAP/PAPE protocol and (b) non-randomized control trials. The following data were extracted: study characteristics/demographics, PAP/PAPE protocols, sEMG parameters, twitch/performance outcomes, and study findings. A modified physiotherapy evidence database (PEDro) scale was used for quality assessment. Fifteen randomized controlled trials (RCTs), with a total of 199 subjects, were included. The M-wave amplitude (combined with a twitch torque outcome) was shown to generally be indicative of PAP. The sEMG amplitudes (in some muscles) were found to be indicative of PAPE during ballistic movements, while a small decrease in the MdF (in certain muscles) was shown to reflect PAPE. Changes in the Hmax/Mmax ratio were found to contribute (temporally) to PAP, while the H-reflex amplitude was shown to be neither indicative of PAP nor PAPE. This review provides preliminary findings suggesting that certain sEMG parameters could be indicative of PAP/PAPE. However, due to limited studies, future research is warranted.

Tactical Situations and Playing Styles as Key Performance Indicators in Soccer.

The game of soccer is complex and unpredictable, demanding multifaceted strategies for success. Performance analysis has evolved, focusing on key performance indicators (KPIs) to determine the factors that most significantly influence a team's success or failure during matches. Traditional performance analysis methods have emphasized quantifiable data like physical exertion and basic play events but often neglected the subtler tactical dimensions that could significantly impact game outcomes. This study aimed to fill the gap in the current literature by creating a comprehensive framework that incorporates tactical situations as KPIs. The objective was to examine whether specific playing styles adopted by teams in various tactical situations and phases of the game could predict the outcome of matches. A dataset comprising all First Division Championship matches from 11 different European countries for the 2021-2022 season was analyzed. Variables representing tactical situations were correlated with match outcomes using a Generalized Estimating Equation framework. The model was specified with a binomial distribution and a logit link function. Statistical significance was determined using Wald χ2 tests with a significance level set at p < 0.05. The study's findings revealed that possession style, counterattacking during offensive transitions, and a balanced aggressive defensive strategy significantly increase a team's chances of victory. It also showed that successful teams tend to focus on central attacks, minimize crossing, and execute strategic plays that lead to final attempts on goal with minimal ball possession. The above findings demonstrate that adopting certain tactical approaches significantly influences soccer match outcomes, highlighting the importance of considering tactical aspects as KPIs.

Effects of Muscular Fatigue on Position Sense in Two Phases of the Menstrual Cycle.

It is generally accepted that local muscular fatigue can negatively affect position sense. Interestingly, it has been proposed that in women, position sense and neuromuscular coordination may be affected by fluctuations of estrogen and progesterone levels. The aim of this study was to examine the possible effect of localized muscle fatigue on knee joint position sense at two phases of the menses: follicular and luteal. Twenty physically active females aged 19-30 years, with normal menses, volunteered for this study. An isokinetic dynamometer was used to evaluate proprioception and perform the fatigue protocol of the knee extensors and flexors. Knee proprioception at rest and after fatigue at three knee target angles (30°, 45°, 60°) was measured. A three-way ANOVA analysis with repeated measures was performed. The results showed that the main effect of fatigue was significant, but no main effect of the menstrual cycle phase was found. Additionally, a main effect was found for the target angle (more flexed target knee joint angles were associated with larger angular error deviations). In conclusion, localized muscle fatigue can significantly reduce the accuracy of active knee joint repositioning in both the luteal and the follicular menstrual phases in young, physically active healthy women.

Analysis of Greek prehistoric combat in full body armour based on physiological principles: A series of studies using thematic analysis, human experiments, and numerical simulations.

One of the oldest complete suits of European armour was discovered in 1960 near the village of Dendra, in Southern Greece, but it remained unknown whether this armour was suitable for extended use in battle or was purely ceremonial. This had limited our understanding of the ancient Greek-Late Bronze Age-warfare and its consequences that have underpinned the social transformations of prehistoric Europe and Eastern Mediterranean. In a series of archeo-physiological studies, merging knowledge in archaeology, history, human physiology, and numerical simulation, we provide supporting evidence that the Mycenaean armour found at Dendra was entirely compatible with use in extended combat, and we provide a free software enabling simulation of Late Bronze Age warfare. A group of special armed-forces personnel wearing a replica of the Dendra armour were able to complete an 11-hour simulated Late Bronze Age combat protocol that we developed from a series of studies based on the available evidence. Numerical simulation of the thermal exchanges in Late Bronze Age warfare extended this conclusion across different environmental conditions and fighting intensities. Our results support the notion that the Mycenaeans had such a powerful impact in Eastern Mediterranean at least partly as a result of their armour technology.

The effects of eccentric exercise-induced muscle damage on running kinematics at different speeds.

This study investigated the effects of knee localised muscle damage on running kinematics at varying speeds. Nineteen young women (23.2 ± 2.8 years; 164 ± 8 cm; 53.6 ± 5.4 kg), performed a maximal eccentric muscle damage protocol (5 × 15) of the knee extensors and flexors of both legs at 60 rad · s(-1). Lower body kinematics was assessed during level running on a treadmill at three speeds pre- and 48 h after. Evaluated muscle damage indices included isometric torque, muscle soreness and serum creatine kinase activity. The results revealed that all indices changed significantly after exercise, indicating muscle injury. Step length decreased and stride frequency significantly increased 48 h post-exercise only at the fastest running speed (3 m · s(-1)). Support time and knee flexion at toe-off increased only at the preferred transition speed and 2.5 m · s(-1). Knee flexion at foot contact, pelvic tilt and obliquity significantly increased, whereas hip extension during stance-phase, knee flexion during swing-phase, as well as knee and ankle joints range of motion significantly decreased 48 h post-exercise at all speeds. In conclusion, the effects of eccentric exercise of both knee extensors and flexors on particular tempo-spatial parameters and knee kinematics of running are speed-dependent. However, several pelvic and lower joint kinematics present similar behaviour at the three running speeds examined. These findings provide new insights into how running kinematics at different speeds are adapted to compensate for the impaired function of the knee musculature following muscle damage.

The effects of eccentric exercise on muscle function and proprioception of individuals being overweight and underweight.

The aim of this study was to estimate the effect of being overweight or underweight on proprioception at rest and after muscle damaging eccentric exercise. Twelve lean, 12 overweight, and 8 underweight female participants performed an eccentric exercise session using the knee extensor muscles of the dominant leg. Muscle damage indices and proprioception were assessed up to 3 days postexercise. The results indicated that proprioception at baseline of the lean individuals was superior to that of the other 2 groups. The overweight individuals exhibited a smaller knee joint reaction angle to release than did the lean group, whereas the underweight individuals exhibited a larger reaction angle to release than did the lean group. After eccentric exercise, proprioception was affected more in the overweight and the underweight groups than in the lean group. The greater exercise-induced muscle damage appeared in the overweight group, and the deficient muscle mass of the underweight participants could explain in part the greater disturbances that appeared in proprioception in these 2 groups than for the lean counterparts. In conclusion, deviating from the normal body mass is associated with significant disturbances in the proprioception of the legs at rest and after participation in activities involving eccentric actions.

Identifying Soccer Players' Playing Styles: A Systematic Review.

Identifying playing styles in football is highly valuable for achieving effective performance analysis. While there is extensive research on team styles, studies on individual player styles are still in their early stages. Thus, the aim of this systematic review was to provide a comprehensive overview of the existing literature on player styles and identify research areas required for further development, offering new directions for future research. Following the PRISMA guidelines for systematic reviews, we conducted a search using a specific strategy across four databases (PubMed, Scopus, Web of Science, and SPORTDiscus). Inclusion and exclusion criteria were applied to the initial search results, ultimately identifying twelve studies suitable for inclusion in this review. Through thematic analysis and qualitative evaluation of these studies, several key findings emerged: (a) a lack of a structured theoretical framework for player styles based on their positions within the team formation, (b) absence of studies investigating the influence of contextual variables on player styles, (c) methodological deficiencies observed in the reviewed studies, and (d) disparity in the objectives of sports science and data science studies. By identifying these gaps in the literature and presenting a structured framework for player styles (based on the compilation of all reported styles from the reviewed studies), this review aims to assist team stakeholders and provide guidance for future research endeavors.