J. Funct. Morphol. Kinesiol., Volume 9, Issue 1 (March 2024) – 56 articles

Chronic ankle instability (CAI) is characterized by muscle weakness and impaired neuromuscular control. This study aimed (a) to assess the impact of external verbal feedback on the dynamic balance of athletes with CAI and (b) to examine the maintenance of dynamic balance ability after the end of the completion of the intervention balance program. Thirty athletes (mean age 21.63 ± 1.53) were randomly divided into three groups: an experimental group with external verbal feedback, 1st control group without external verbal feedback and the 2nd control group without balance training and without feedback. Assessments using a balance board and the ‘Y-balance’ test were conducted before and after the balance training period. Additionally, participants completed the Cumberland Ankle Joint Instability Tool. A retention test of balance ability was administered after the 4-week intervention period. Statistical analysis revealed a significant overall improvement in balance (F(2,36) =5.96, p = 0.006, partial η² =0.249), including those with no balance training, but no significant differences between the groups. Thus, the external verbal feedback did not show a positive impact on the balance ability between the three different groups. Also, the experimental group with the external verbal feedback demonstrated maintenance of dynamic balance learning ability. Although it appears that balance training has a positive effect on the dynamic balance of individuals with CAI, a non-positive impact of external verbal feedback was found. Also, it appears that external verbal feedback significantly led to sustained retention of balance learning ability. Further research is recommended to validate these findings. Full article

While neck pain can be defined in clinical terms, in most cases the underlying pathophysiology is largely unknown. Regional cervical spine range of motion is often found to be reduced in patients with neck pain compared to persons without pain although it is not clear if the decreased range is cause or effect. Less is known about the role of intervertebral kinematics and how that might be related to the presence of disc degeneration. In this study, the prevalence of intervertebral disc degeneration and continuous cervical intervertebral motion were both measured utilizing quantitative fluoroscopy (QF) in patients with subacute or chronic neck pain (n = 29) and gender-matched healthy controls (n = 30). A composite disc degeneration (CDD) score was calculated for each participant from the first, neutral, lateral fluoroscopic image. Intervertebral motion sharing parameters of motion-sharing inequality (MSI) and motion-sharing variability (MSV) were derived from the active cervical motion sequences obtained while patients were seated. The objective was to determine if average age, CDD, MSI, and MSV values were correlated and if there were differences in these variables between the neck pain group and the healthy control group. Correlation analysis was conducted for age, CDD, MSI, and MSV in each group. Age was moderately correlated with MSV in cervical spine extension in patients only (r = 0.63, p < 0.001). There were no significant differences in the prevalence of disc degeneration (CDD) between patients, who had on average mild pain and related disability, and healthy controls (median CDD 2 both groups, p = 0.94). There were also no significant differences in either flexion or extension intervertebral motion-sharing inequality or variability (MSI or MSV) between groups as measured during active cervical motion. Full article

The daily exercise habits and play activities of children are known to have a significant impact on the development of body control. However, previous studies have not adequately explored the correlation between force regulation during submaximal visual effort, exercise, and play experience. This study aimed to examine the correlation between exercise habits and play experience and their impact on the ability to regulate force. This study involved 23 children with an average age of 9.2 ± 1.0 years. The participants were required to match their force exertion during submaximal effort to a varying demand value displayed in a sinusoidal pattern on a screen (controlled force exertion, CFE). Individual interviews were conducted to gather information on the exercise experience (time, frequency, and duration) and play activities (number of experiences and frequency). Multiple regression analysis was performed to determine the association among exercise experience, play activity, and CFE. The results indicated that the amount of exercise experience was not significantly associated with CFE (β = −0.203, p = 0.254). However, in terms of play activities, the number of play experiences was associated with CFE (β = −0.321, p = 0.038). On the contrary, play frequency was not significantly associated with CFE (β = −0.219, p = 0.191). These findings suggest that play activities are effective in improving force regulation during childhood and that a greater variety of play experiences may be important. Full article

One of the most important implications of technology in swimming is to control training loads. Lactate control, video-analysis of the technique or the assessment of specific actions, i.e., the vertical jump, have helped to provide load adaptation indicators in swimmers in recent decades. However, these indicators have led to a longer application time, due to their indirect procedure and the need to analyze each variable. The aim of this study was to analyze whether inspiratory spirometry values can serve as a training load control tool in swimmers. Countermovement jump (CMJ), Inspiratory Force Index (S-INDEX) and Peak Inspiratory Flow (PIF) were evaluated with a load of 3 cm H₂O before, during and after performing a swimming performance test (critical speed test: specific warming up, 400 m and 100 m freestyle). Positive correlations were found between S-INDEX and jump height after warm-up, after 400 m and at the end of 100 m (Spearman = 0.470, R² = 0.280; Spearman = 0.508, R² = 0.392; Spearman = 0.458, R² = 0.359, p < 0.05, respectively). Moreover, positive correlations were also found between PIF and jump height at the same evaluated moments (Spearman = 0.461, R² = 0.305; Spearman = 0.493, R² = 0.386; Spearman = 0.454, R² = 0.374, p < 0.05). Both the S-INDEX and the PIF could serve as useful tools for swimmer load control, allowing coaches to make more immediate decisions. Full article

Periodontal disease (PD) is considered a risk factor for cardiovascular events. However, its relationship to chronic heart failure (CHF) is unclear. The aim was to compare cardiac and inflammatory parameters in CHF patients with (PG) versus without periodontitis (NPG). The following parameters were recorded in 58 patients: periodontal screening and recording (PSR), troponin T, NT-proBNP, C-reactive protein (CRP), interleukin-6 (IL-6), blood pressure, heart rate, ejection fraction (EF), ventricular systolic and diastolic function parameters, incremental test, and three questionnaires (Mediterranean Diet Adherence Screener, MEDAS; Oral Health Impact Profile, OHIP-14; Patient Health Questionnaire, PHQ). The serum levels of NT-proBNP and troponin T were significantly higher in the PG, and the left ventricular systolic and diastolic function parameters were significantly lower. The correlation analysis showed age as the only independent risk factor for periodontitis and cardiac biomarkers. No significant group differences were found in the MEDAS, OHIP-14, and PHQ scores, or in CRP, IL-6, and cardiocirculatory parameters. Overall, the BMI correlated significantly with the mean PSR and total cholesterol. The occurrence of increased PSR together with increased age and cardiac risk parameters does not exclude an association between periodontitis and CHF, though no positive correlation was calculated. Periodontitis may be a modifiable risk factor for CHF. Its treatment may help to control the inflammatory burden. Full article

This study investigates the significance of skeletal transverse dimension (STD) in orthodontic therapy and its impact on occlusal relationships. The primary goal is to enhance understanding and promote the integration of transverse skeletal diagnostics into routine orthodontic assessments. To achieve this aim, the study employs a comprehensive approach, utilizing model analysis, clinical assessments, radiographic measurements, and occlusograms. The initial step involves a meticulous assessment of deficiencies in the maxilla, mainly focusing on transverse dimension issues. Various successful diagnostic methods are employed to ascertain the type and presence of these deficiencies. Furthermore, the study compares surgically assisted maxillary expansion (SARME) and orthopedic maxillary expansion (OME) in addressing skeletal transverse issues. Stability assessments and efficacy analyses are conducted to provide valuable insights into the superiority of SARME over OME. The findings reveal that proper evaluation of STD is crucial in orthodontic diagnosis, as overlooking transverse dimension issues can lead to complications such as increased masticatory muscle activity, occlusal interferences, and an elevated risk of gingival recession. Surgically assisted maxillary expansion emerges as a more stable solution than orthopedic methods. In conclusion, incorporating skeletal transverse diagnostics into routine orthodontic assessments is imperative for achieving optimal occlusal relationships and minimizing negative consequences on dentition, periodontium, and joints. The study emphasizes the significance of accurate three-dimensional assessments and recommends the consideration of SARME over OME for addressing skeletal transverse deficiencies. Finally, the Collaborative Cross (CC) mouse model is also a novel mouse model for studying complex traits. Exploring the Collaborative Cross mouse model opens avenues for future research, promising further insights into transverse skeletal issues in orthodontics. Full article

The reflexive responses to resist external forces and maintain posture result from the coordination between the vestibular system, muscle, tendon, and joint proprioceptors, and vision. Aging deteriorates these crucial functions, increasing the risk of falls. This study aimed to verify whether a training program with water bags, an Instability Neuromuscular training (INT) using the inertial load of water, could positively impact balance ability and dynamic stability. This study was conducted with twenty-two healthy older women aged ≥ 65 (mean age: 74.82 ± 7.00 years, height: 154.20 ± 5.49 cm, weight: 55.84 ± 7.46 kg, BMI: 23.55 ± 3.58 kg/m²). The participants were randomly allocated into two groups: a group that used water bags and a control group performing bodyweight exercises. The intervention training lasted 12 weeks, with 2 sessions per week totaling 24 sessions, each lasting 60 min. The pre- and post-tests were compared using t-tests to examine within- and-between-group differences. The effect size was examined based on the interaction between group and time using a two-way repeated measures ANOVA. The Modified Timed Up and Go manual (TUG manual), Sharpened Romberg Test (SRT), and Y-balance test (YBT) were conducted to assess dynamic stability, including gait function, static stability, and reactive ability. In comparison between groups, the waterbag training group showed a decrease in task completion time associated with an increase in walking speed in the TUG manual test (p < 0.05), and an increase in static stability and reaction time in the Sharpened Romberg test with eyes closed (p < 0.05), and an increase in single-leg stance ability in both legs in the Y-balance test (p < 0.05). All statistical confidence interval levels were set 95%. INT using the inertial load of water enhanced the somatosensory system and gait related to dynamic stability in older women. Therefore, the clinical application of this training program is expected to reduce the risk of falls in healthy older women, improving dynamic stability related to gait. Full article

Athletes engaging in overhead activities often face injury risks, emphasising the need for reliable assessment tools. This study focused on the translation and psychometric evaluation of the Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow Score into Greek (Gr-KJOC) for assessing upper limb function in Greek-speaking overhead athletes. The Gr-KJOC underwent meticulous translation and adaptation processes, ensuring linguistic equivalence and cultural relevance. A sample of 60 athletes participated in the psychometric evaluation, including assessments of internal consistency, test–retest reliability, construct validity, and structural validity. The Gr-KJOC demonstrated excellent internal consistency (Cronbach’s alpha = 0.95), indicating consistent measurement of the underlying construct. Test–retest reliability was excellent (ICC = 0.95), with low measurement errors. Construct validity was confirmed through correlations with the Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire. Structural validity revealed a unidimensional structure with high explained variance (75%). No floor or ceiling effects were observed, and the questionnaire proved feasible, with an average completion time of 6 min. The Gr-KJOC emerges as a reliable, valid, and feasible tool for evaluating upper limb function in Greek-speaking overhead athletes. Its psychometric properties support its utility in clinical and research contexts, contributing to the effective assessment and management of shoulder and elbow conditions in the realm of overhead sports in Greece. Full article

The impact of exercise-specific face masks (ESFMs) in aerobically fit individuals on physiological, perceptual, respiratory, and performance responses remains unclear. How ESFMs mitigate exercise-induced bronchoconstriction (EIB) is also unknown. Thus, this study aimed to determine how an ESFM altered within-exercise physiological, perceptual, respiratory, and performance responses to graded treadmill exercise. Twenty-four individuals (11 females) completed a discontinuous graded exercise test on a treadmill under two conditions (ESFM and unmasked). Physiological, respiratory function, and perceptual measures were assessed. Performance was determined by time to exhaustion. Statistical analyses included linear mixed-effects modeling, repeated measures analysis of variance, and pairwise comparisons using an alpha value of 0.05. ESFM use significantly impaired performance (median = −150.5 s) and decreased arterial oxygen saturation at maximal intensity (mean = −3.7%). Perceptions of air hunger and work of breathing were elevated across submaximal and maximal intensities. Perceived exertion and breathing discomfort were significantly elevated submaximally but not maximally. Spirometry measures were not significantly different at termination but were significantly improved at submaximal intensities in participants with and without EIB. ESFM use in fit individuals increased perceptual discomfort, impaired performance, and augmented arterial desaturation. Respiratory function improvements were observed but were accompanied by adverse perceptual sensations. Despite this, performance impairments may limit the real-world utility of ESFMs for athletes. Full article

Compared with other sports, running is popular sport for children throughout the world. Over the last few decades, marathon running has become increasingly popular even in the age group below 18 years. While the majority of youth athletes fall within the 16–18 age range, it is noteworthy that there are also participants younger than 12 years engaging in marathon races. Advice on the safety of youth athletes participating in these events is frequently sought by parents, coaches, sport scientists, and medical professionals, particularly concerning potential short- and long-term health consequences. The act of marathon running has the potential to impact key organ systems during the crucial phases of growth and development. To ensure the safety of marathon running in youth runners, it is essential to address multiple physiological and psychological aspects of health. These recommendations are directed towards ensuring the safe participation of youth athletes in marathon races through proper and individualized assessments. Full article

Sport-related concussions (SRCs) are a mild traumatic brain injury (mTBI) that induces transient symptoms in athletes. These symptoms provide avenues for developing emerging technologies to diagnose SRCs, in particular ocular and vestibular dysfunction. The following study aims to assess the reliability of visual smooth-pursuit technology (EyeGuide Focus) in amateur field-sport athletes. A convenience sample of 30 mixed-gender athletes (mean age = 24.89 ± 6.81 years) completed two testing sessions separated by 2–7 days. Participants were tested at rest, free from distraction, and completed a 10 s smooth pursuit while seated. Participants completed 2–4 practice trials before completing three tests at each session. Appropriate difference, reliability, and repeatability tests were performed in Statistical Packages for the Social Sciences. No significant difference existed between the time points (p > 0.05). The reliability between sessions was poor (ICC = 0.24; 95% CI = 0.03–0.42), and the mean coefficients of variation were 20% and 21% for each session, indicating poor repeatability. However, the implementation of practice trials did prevent the familiarization effects that are evident in the previous literature (p > 0.05). The within-session reliability of EyeGuide Focus has varied from poor (ICC ≤ 0.50) to good (ICC = 0.75–0.90) in the previous literature, indicating the fact that greater research is required before this tool can be implemented in applied settings. Full article

Post-stroke gait is characterized by slow and asymmetrical hemiparetic gait. This is attributed to the paretic lower limb which has limited plantar propulsion. The most effective method to restore paretic limb function is constraint-induced movement therapy (CIMT), which promotes the usage of the paretic limb by restricting the movement of the unafflicted limb. However, due to the necessity of both lower limbs to perform gait, CIMT methods could not be directly applied for gait rehabilitation. In this study, we explore the feasibility of utilizing a knee scooter as a means to facilitate CIMT gait training. We hypothesize that if lower limb kinematics and muscle activation patterns during gait with a knee scooter match that of natural gait, the knee scooter could be utilized for CIMT gait training. We measured the lower-limb joint angles, plantar force, EMG patterns, stride length, and step times of 13 healthy subjects during gait with a knee scooter and natural gait. The results suggest that the gait patterns while using the knee scooter closely resemble those of natural gait. Full article

It is widely demonstrated that moderate-intensity exercise is associated with improved fitness in non-communicable chronic diseases. However, there are no specific guidelines available for transplant recipients. Body composition is closely linked to exercise capacity, typically estimated by cardiopulmonary testing, but its potential correlation with cardiovascular health outcomes has not been investigated yet. This study aims to evaluate and compare cardiorespiratory performance and body composition in two groups of liver and kidney transplant recipients. A mixed group of transplant recipients (10 kidney and 15 liver) participating in a lifestyle reconditioning program through unsupervised physical exercise prescription was examined. Both groups were assessed using bioimpedance analysis (BIA), lifestyle, and physical activity levels by IPAQ questionnaire and cardiopulmonary testing (CPET). The two groups differed by IPAQ examination: liver transplant patients practiced more physical activity. Statistically significant differences were found in peak VO₂/HR (oxygen pulse), which was higher in the kidney group compared to the liver group (15.63 vs. 12.49 with p < 0.05). Body composition did not show significant differences in BMI and the percentage of FM/FFM (FFM: 78.04 ± 7.7 in Kidney T vs. 77.78 ± 7.2 in Liver T). Systolic pressure measured at the peak was significantly higher in the liver group (162.6 vs. 134 with p < 0.01). The correlation between the CPET and BIA parameters showed a positive VO₂ max and FFM mass trend. The results suggest differences in cardiorespiratory fitness between the two populations of solid organ transplant recipients despite not being related to the physical activity level. The data support the importance of body composition analysis in sports medicine and the prescription of physical exercise, especially considering the potential correlation with VO₂ max, even though home-based exercise does not seem to alter it substantially. BMI does not appear to be a determinant of cardiovascular performance. Other determinants should be investigated to understand the differences observed. Full article

Foam rolling is widely used in fitness, sports, rehabilitation, and injury prevention. However, there are limited data available on the effect of foam rolling techniques on the upper limbs. The aim of this investigation is to assess the effects of foam rolling the latissimus dorsi area during the rest period between two consecutive lat pull-down exercise (LPDE) sets. Seventeen resistance training experienced volunteer male subjects (25.8 ± 3.4 years; 180.3 ± 9.0 cm; 79.7 ± 9.9 kg) participated in this research. Each subject performed 2 training sessions of LPDE in a random order, separated by one week. Each session consisted of 2 sets of maximum repetitions using 85% of their one-repetition maximum (1RM), with a 7 min rest period between sets. The rest period condition between sets was different in the 2 sessions: passive rest (Pr) or foam rolling the latissimus dorsi muscle bilaterally for 3 sets of 45 s (FRr). The following variables were assessed for each LPDE set: number of repetitions (REPS), average excursion per repetition in millimeters (EXC), average power of the set in watts (AP) and rating of perceived exertion (RPE). Pr did not show any significant change between the first and the second LPDE set for REPS, EXC, and AP. However, there was a significant increase for RPE (8.4 ± 0.5 vs. 8.9 ± 0.5 a.u., p = 0.003) between the two sets. FRr resulted in an increase for REPS (7.1 ± 1.5 vs. 8.2 ± 1.3, p < 0.001) and AP (304.6 ± 61.5 W vs. 318.8 ± 60.8 W, p = 0.034) between the first and the second LPDE sets, but no changes were observed for EXC and RPE. The use of foam rolling techniques on the latissimus dorsi area during the complete rest period between sets in LPDE at 85% 1RM appears to improve the number of repetitions and the movement power without affecting the RPE during the second set. Full article

Participating in sports has been shown to promote overall wellness and, at the same time, reduce health risks. As more people are participating in sports, competitions have increased, and every aspect of the game has been focused by coaches and athletes in order to improve performance. One of these aspects is the warm-up session. The purpose of this study was to investigate the acute effect of a dynamic warm-up versus a proprioceptive neuromuscular facilitation (PNF) warm-up on the sprint and jump performance of recreationally active men. Thirty (n = 30) males were randomly assigned to undergo three sessions of different warm-up types, 72 h apart, involving either proprioceptive neuromuscular facilitation (PNF), dynamic stretching (DS), or no stretching session (control). The PNF and dynamic modes of stretching improved vertical jump performance, F (2.58) = 5.49, p = 0.046, to a certain extent (mean + 3.32% vs. control, p = 0.002 for dynamic and mean + 1.53% vs. control, p = 0.048 for PNF stretching). Dynamic stretching is best used to get a better vertical jump height. Sprint performance was also increased to a greater extent following the stretching session, F (2.58) = 5.60, p = 0.01. Sprint time was +1.05% faster vs. the control, with a value of p = 0.002 after dynamic stretching, while PNF stretching demonstrated a sprint time of +0.35% vs. the control, with a value of p = 0.049. Dynamic stretching showed a better sprint performance and also vertical jump height performance in this study. PNF and dynamic stretching prove to be equally efficacious in flexibility conditioning depending on the type of movement involved. This type of stretching should be utilized to help preserve or improve the performance output of physical activity, especially in sprinting and jumping events. Full article

Hydrostatic weighing (HW) requires full submersion with the lungs at residual volume (RV) which is uncomfortable. Therefore, the purpose of this study was to find a more comfortable way to complete HW. A HW system was used to complete three comparisons: comparison 1: change in head position (head above water vs. head below water (HAW vs. HBW)), comparison 2: change in lung volume (total lung capacity (TLC) vs. RV), and comparison 3: change in head and lung volume changes. Participants were separated by males (n = 64) and females (n = 58). Comparison 1: HAW resulted in higher mean percent body fat (PBF) than HBW (4.5% overall, 3.8% in males, 5.4% in females, p < 0.05). Comparison 2: TLC resulted in lower mean PBF than RV (5.1% overall, 5.3% in males, 4.8% in females, p < 0.05). Comparison 3: HAW@TLC resulted in significantly lower (1.5% lower, p = 0.003) mean PBF for males but was not significantly lower for females or overall (0.6% higher, p = 0.39, 0.6% lower, p = 0.18, respectively) compared to HBW@RV. In conclusion, keeping the head above water and taking a deep inhale makes HW a more enjoyable, and accessible experience for everyone while still producing accurate PBF results. Full article

Transcutaneous electrical nerve stimulation (TENS) has proven effective in treating pain in many experimental and clinical studies. In addition to the analgesic effect, direct TENS of peripheral nerves had anti-inflammatory and regenerative effects in the treatment of distal polyneuropathy and spinal cord injury. This work demonstrates the experience of using direct TENS in the treatment of a 52-year-old patient with post-COVID-19 Guillain–Barré (GBS) and acute transverse myelitis (ATM) overlap syndrome. Direct TENS of peripheral nerves showed high efficiency in enhancing the therapeutic effect of combined plasma exchange and pharmacotherapy by 89.5% with a significant reduction in neuropathic pain, motor and sensory deficits, bladder and bowel disorders and regression of neurophysiological changes. We suggest that direct TENS of peripheral nerves can be a promising option for combined therapy of GBS and ATM overlap syndrome and other diseases with the simultaneous development of distal polyneuropathy and spinal cord injury. Further trial studies are required. Full article

Background: Achondroplasia is a rare genetic skeletal condition characterized by disproportionate short stature. There is limited evidence on postural control in adults with achondroplasia and how lower limb lengthening (intervention) interacts with body dynamics. This study investigated sway variability during quiet standing in adults with achondroplasia with natural growth (N) and with lower limb lengthening (LL). Methods: Sixteen adults performed bilateral/unilateral standing tasks. Linear (total excursion, amplitude, and ellipse area) and nonlinear (sample entropy and correlation dimension) center of pressure sway metrics were analyzed in the anteroposterior/mediolateral directions. Relationships between posture metrics, strength, and physical activity were explored. Between-groups statistics were calculated. Results: The LL group exhibited amplified linear sway, indicating larger postural deviations, and reduced sample entropy and correlation dimension, indicative of more rigid and repeated corrections. The N group exhibited more unpredictable and adaptive movement corrections. Numerous correlations emerged between strength and posture measures, with relationships altered by intervention. Conclusions: Adults with achondroplasia display distinct balance strategies influenced by intervention. The results indicate that LL is associated with altered variability and adaptability compared to natural development. Relationships with muscle strength spotlight a key role of muscle capacity in postural control modulation after growth alterations in this population. Full article

Findings are inconsistent with regards to whether menstrual cycle phase-associated changes in physical functioning exist. It is possible that such discrepancies are due to varying rigour in experimental approaches. The current study aimed to systematically evaluate any effect of carefully tracked menstrual cycle phase on precisely measured muscle structure and function in a physically active group (contemporary dancers). Eleven women aged (M [SD]) 23.5 [2.94] years, undergoing 10.5 [1.73] hours of contemporary dance practice and 6.12 [2.36] hours of other physical activity per week, were recruited. Sex hormone level (enzyme-linked immunosorbent assays (ELISA), skin temperature and ovulation kits), physical pain assessments (Ice Water Test, Visual Analogue Scale, The Physical Activity Readiness Questionnaire, Self-Estimated Functional Inability Because of Pain Questionnaire, and Pain Anxiety Symptoms Scale), muscle architecture measurement (B-mode ultrasonography), and physical functioning (dynamometry, force-platform and electromyography) on both lower limbs were measured at three time points during one cycle, following three months of menstrual cycle monitoring. There was no difference in musculoskeletal flexibility variables between follicular, ovulatory, or luteal phases. Nonetheless, oestrogen change was associated with variability in 11 musculoskeletal variables, progesterone change was associated with variability in 7, and relaxin change was associated with variability in 15. Negative correlations existed between progesterone and flexibility and between oestrogen and jump variables. Moreover, oestrogen and relaxin were associated with increased musculoskeletal compliance, whilst progesterone was associated with increased muscle stiffness. In short, in absolute sex hormone levels, ‘inter-individual’ variances appear more impactful than ‘intra-individual’ variances. Not only are oestrogen and progesterone associated with differing musculoskeletal outcomes, but relaxin is also associated with musculoskeletal compliance changes. These effects are anticipated to impact jump height and flexibility, and hence, they could be expected to affect overall physical performance, including dance. Full article

During the second wave of the COVID-19 pandemic, a young adult presented symptoms that were reported at first evaluation to be a frozen shoulder (adhesive capsulitis). The patient’s history, clinical manifestations related to the onset of pain, unilateral weakness, and physical examination led to a physiotherapy referral. Subsequent instrumental investigations showed an idiopathic brachial neuritis known as Parsonage–Turner Syndrome (PTS). Contrary to recent descriptions in the literature, the patient did not experience PTS either after COVID-19 vaccination or after COVID-19 virus infection. The proposed multimodal treatment, considering the patient’s characteristics, led to a recovery of muscle strength and function of the upper limb, observed even three years after the acute event. The frequency of rehabilitation treatment, the choice of exercises, the dosage, and the methods of execution require further studies in order to define an evidence-based treatment. Full article

The unprecedented COVID-19 health crisis severely disrupted global sports in 2020, prompting lengthy suspensions followed by resumed competitions under abnormal behind-closed-doors conditions without fans. These disruptions necessitated tactical adaptations by coaches and teams, attempting to still achieve successful outcomes. This study investigates the pandemic’s impacts on performance metrics and indicators within Spanish professional soccer. Utilizing systematic notational analysis, 760 match cases from the 2019–2020 La Liga season were examined, comprising 27 matchdays from the pre-COVID context and 11 after resumption. Multivariate tests identified significant pre/post differences and interactions for various technical indicators including shots, cards, corners, and offside calls. The pandemic was associated with a reduction from 12 to just 5 identifiable playing styles, suggestive of increased conservatism featuring more passive play, limited attacking depth, and horizontal ball movement. Such tactical changes appear provoked by condensed fixture scheduling post-lockdown, the lack of supportive crowds, and compromised player fitness/recovery. By quantifying these COVID-precipitated changes, the analysis provides tangible evidence for coaches to make informed adjustments in training and preparation for functioning effectively in disrupted environments. The findings emphasize that versatility and flexibility will be vital to optimize performance during times of unprecedented uncertainty. Full article

Tennis is a complex sport based on unpredictability that requires adequate physical and psychological preparation to prevent injuries. The aim of this study was to investigate the effects of 8-week specific core stability training on postural stability in competitive adolescent tennis players, aged between 14 and 19 years old. Sixty-one participants were randomly allocated into two groups: experimental (n = 32) and control (n = 29) groups. The first group wore proprioceptive insoles 8 h a day and performed a detailed training 3 times a week for 8 weeks; the second group only received proprioceptive insoles to wear 8 h a day for 8 weeks. The postural stability parameters (center-of-pressure length, center-of-pressure velocity, and 95% confidence ellipse sway area) included three assessment times: baseline (T₀), intermediate test (T₁), post-test (T₂), and retention test (T₃). Data analysis showed a significant improvement in the experimental group compared with the control group, indicating a large effect size in center-of-pressure length, ellipse sway area, and center-of-pressure velocity at T₂ and T₃ (p < 0.05). In conclusion, our results suggest that a specific and detailed core stability training plays a significant role in improving balance and postural stability in young tennis players, especially in terms of preventing the risk of injury. Full article

The COVID-19 lockdown and the consequent distance school learning made epochal changes in children’s lifestyles; however, little is known about the lockdown effects on school teacher habits. The aim of this observational study is to examine differences in the lifestyle of nursery (NS) and primary (PS) school teachers after one of the COVID-19 lockdowns and investigate the relationship between perceived physical/mental health and demographics, weight status and lifestyle determinants, such as adherence to the Mediterranean Diet (MD) and physical activity level (PAL). A total sample of 265 participants (49.22 ± 6.95 years) filled out an online information questionnaire and standardized questionnaires to collect data on the Physical Component Summary (PCS), Mental Component Summary (MCS), PAL and MD-adherence. A t-test or ANOVA analysis was used to assess differences between quantitative variables: Mann–Whitney U or Kruskal–Wallis tests for qualitative variables. Spearman’s correlations and multinomial logistic regression analyses were performed to identify categorical factors associated with classes of PCS and MCS. Teachers showed sufficient/high PAL, with a significantly higher level in the PS group (p < 0.05). This last showed a higher PCS score (p < 0.05). No differences between groups were found for MD-adherence, which was moderate/fair in both groups, and MCS, which was sufficient/good. Logistic regression showed that the only positive predictor of a high PCS was being physically active (OR 2.10, 95%CI 1.05–4.2, p < 0.05), while MCS was positively associated with normal weight status (OR 0.48, 95%CI 0.33–0.78, p = 0.020). This study highlights that PS teachers are more active than the NS group and perceive a higher physical health level. Mere predictors of physical and mental well-being are PA practice and being normal weight, respectively. This suggests that interventions to improve perceived health in this work category should be focused on the promotion of physical activity practice and on the maintenance of an optimal weight status. Full article

The study aimed to evaluate the impact of listening to preferred music during active/passive rest on power output and heart rate in barbell squats (BS) and bench presses (BP). Fifteen participants (13 males and 2 females), moderately resistance trained, were engaged in four randomized experimental sessions with varying rest intervals (active/passive) and music presence (listening or not). Each session involved three sets of three repetitions of BS and BP at a 50% one-repetition maximum. ANOVA showed a significant main effect of the set for BP relative mean and peak power output (p < 0.001; both). The post hoc comparisons indicated a significantly higher BP relative mean and peak power output in set_2 (p < 0.001; effect size [ES] = 0.12 and p < 0.001; ES = 0.10) and set_3 (p < 0.001; ES = 0.11 and p = 0.001; ES = 0.16) in comparison to set_1. Moreover, a main effect of the set indicating a decrease in BS relative peak power output across sets was observed (p = 0.024) with no significant differences between sets. A significantly higher mean heart rate during active rest in comparison to passive rest was observed (p = 0.032; ES = 0.69). The results revealed no significant effect of listening to music on relative power output and heart rate during BS and BP. Full article

A topical medical device, AI500^®, constituted of a single-chain polypeptide embedded in hyaluronic acid, was tested and evaluated in patients with reduced knee function due to osteoarthritis and other knee conditions. A total of 35 participants with reduced knee function assessed by the WOMAC Physical Function score were recruited. Four study visits were planned, from the first application at V0 to 1 week follow up at V3. Patient symptomatology was evaluated after 24 h (V1) and after 48 h (V2) through phone contact, and after 1 week from V0, on site (V3). The overall duration of the follow up was one week. An amelioration of 40% in WOMAC Physical Functional scores after 1 week of treatment was recorded, thus achieving the primary endpoint of 20%. Furthermore, a reduction of 29% in Physical Functional scores and of 28% in total WOMAC scores between V0-V2 was registered, together with a decrease of 39% between V0 and V3. The NRS scale showed a 29% and 37% reduction in pain between V0-V1 and V0-V2, respectively. Product safety was confirmed by the very low rate of adverse effects, non-device related, observed in only 2 patients out of 35, resolved spontaneously within 24–48 h. No safety concerns or risks associated with the use of the device were highlighted. There are few the studies on the topical use of HA-based gels for the treatment of knee problems. Compared to invasive intra-articular injections and oral pharmacological therapies used in cases of knee pain, the topical application of AI500^® is non-invasive, safe, and appreciated by patients. Good results in terms of functional improvement and symptoms resolution were obtained in less than 1 week. Full article

Cardiovascular capacity, expressed as maximal oxygen uptake (VO_2max), is a strong predictor of health and fitness and is considered a key measure of physiological function in the healthy adult population. The aim of this study was to investigate the influence of the physical activity levels (PA_level) of participants in the StepTest4all (validated protocol for the estimation of VO_2max in adults). The sample consisted of 69 participants, including 27 women (age 21.7 ± 3.6 years; body mass = 63.5 ± 14.8 kg; height = 1.64 ± 0.06 m; body mass index = 23.7 ± 5.3 kg/m²) and 42 men (aged 21.7 ± 3.4 years; body mass = 72.0 ± 7.3 kg; height = 1.77 ± 0.07 m; body mass index = 23.1 ± 2.1 kg/m²). The participants were assigned to one of the two groups: (i) the VO_2max prediction group and (ii) the prediction model validation group. In the multiple linear regression, the following predictors of VO_2max remained significant: sex (p < 0.001), physical activity level (p = 0.014), and HRR₆₀ (p = 0.020). The prediction equation (R² = 74.0%, SEE = 4.78) showed a close and strong relationship between the measurements and can be expressed as follows: VO_2max = 17.105 + 0.260·(HRR₆₀) + 8.563·(sex) + 4.097·(PA_level), in which HRR₆₀ is the magnitude of the HR decrease (bpm) in one minute immediately after stopping the step, and sex: men = 1, women = 0, and PA_level is level 1 (low), level 2 (moderate), and level 3 (high). The StepTest4all was shown to be a suitable method for estimating cardiovascular capacity, expressed as VO_2max, in young adults. Retaining PA_level as a significant predictor allows us to better individualize the participants’ VO_2max. Full article

This study aimed to assess which multidimensional performance indexes were the best predictors of talent identification in volleyball. Fifty-five female players (age: 13.8 ± 1.81 years; mass: 55.12 ± 8.12 kg; height: 158.23 ± 7.62 cm) were clustered into two groups according to some physical characteristics (i.e., the first group included players with more favorable performance predictors). Musculoskeletal Fitness (MSF), Functional Motor Competence (FMC), and Declarative Tactical Knowledge (DTK) were measured as multidimensional indexes of performance. Moderate-to-large differences between groups were found for each index in favor of the first group. Regression analyses were performed to examine the variance explained by MSF, FMC, and DTK in the two groups. A model with FMC components explained slightly more variance in the group predictor variables (R² = 0.53) than a model using only MSF components (R² = 0.45). Among FMC components, the score of the Throw-and-Catch test resulted in the best predictor (Odds Ratio = 1.58) for determining group selection, followed by the score of the Supine-to-Stand-and-Go test (Odds Ratio = 0.02). An additional model composed by MSF and FMC significant predictors (i.e., functional fitness index) and DTK explained 63% of the variance (R² = 0.63), and these were significant predictors of group membership (Odds Ratio = 6.32 and Odds Ratio = 1.51, respectively). A more comprehensive multidimensional analysis of youth performances is warranted to identify and monitor the best players in a youth volleyball context. Full article

The aim of this research is to verify whether there is a difference in the average duration of the active and passive phases of the game between volleyball and beach volleyball. A total of 2392 active and passive phases were measured during high-level volleyball and beach volleyball matches for males. Matches were played by four teams (53 players) in indoor volleyball (age 29 ± 4.94 years) and five teams (10 players) in beach volleyball (age 28.27 ± 6.64 years). Possible differences were evaluated using the Mann–Whitney U test. The average duration of the active phase in volleyball is 5.55 s ± 4.38 s. In beach volleyball, the active phase lasts marginally longer, at 6.00 s ± 3.44 s. The average duration of the passive phase in volleyball is 35.27 s ± 25.96 s and it lasts longer than the average passive phase in beach volleyball at 33.82 s ± 22.98 s. The Mann–Whitney U test showed a statistically significant difference (p = 0.00) between the active phases in volleyball (Md = 3.53, n = 727) and beach volleyball (Md = 3.43, n = 484), U = 140770.00, z = −5.90 with small effect according to Cohen’s criterion (r = 0.14). The Mann–Whitney U test (U = 160773.00, z = −1.10) showed no statistically significant difference in the average duration of the passive phases at volleyball and beach volleyball. This research determined that there is a statistically significant difference in the average duration of the active phase between volleyball and beach volleyball. The new insights gained in this research can support a more precise programming of training intensity in high-level volleyball and beach volleyball. Full article

The main objective of this study was to investigate the influence of carbohydrate intake (cyclodextrin) on performance during the performance of two consecutive workouts of the day (WODs) lasting 20 min each. Twenty-one male CrossFit (CF) athletes (29.5 ± 4.3 years; 72.81 ± 12.85 kg; 1.74 ± 0.06 m; 3.41 ± 1.21 years of experiences) participated in a crossover, randomized, and double-blind study. The effect of supplementation with 30 g of cyclodextrin (SG) (Cluster Dextrin^®) or placebo (PG) (Bolero Advanced Hydration^®) was evaluated on the performance of two specific WOD. Additionally, the effect on handgrip maximum strength, countermovement jump (CMJ), Wingate test, and 1 RM bench press test was evaluated. The effect on blood glucose and lactate was also evaluated. No differences were found in time, height, and power (W/Kg) in CMJ. However, there was a percentage improvement in CMJ jump power (W) (p < 0.05) between the groups, assuming an improvement in performance due to the intervention. Moreover, both conditions experimented differences in execution speed between sets (p < 0.05) in pre-WOD, and differences in post-WOD only in the placebo group, as well as decreases in this variable per repetition across the set (p < 0.01) in both conditions. However, no differences were found in the rest of the variables. Supplementation with 30 g of cyclodextrin did not have any metabolic or performance effects in CF tests. Although some differences between groups were observed in CMJ and power tests for bench press, the data are not conclusive and further research is needed in this regard. Full article