J. Funct. Morphol. Kinesiol., Volume 8, Issue 4 (December 2023) – 29 articles

This study aimed to analyze the effects of a 5 min virtual reality training program (VR) on dynamic balance in tennis players. Fifty-eight college tennis players (mean age 22.9 ± 3.1 years, weight 73.9 ± 10.8 kg, height 176.6 ± 8.4 cm) were allocated to either the control group (placebo) (CG, n = 20) or the right-handed experimental group (RTG, n = 20) and left-handed experimental group (LTG, n = 18), both of which took part in the 5 min VR intervention program. Pre-tests included anthropometric measures and the Y Balance Test (YBT), and the post-test was the Y Balance Test (YBT). Three YBT trials were performed in anterior (ANT), posterolateral (PL), and posteromedial (PM) directions. After the training intervention, in the right-handed experimental group (RTG), significant differences were observed for two variables: anterior reach (right foot) (p = 0.00) and posterior medial reach (right foot) (p = 0.03). In other analyzed variables, there were no significant differences. Additionally, the effect size was small. In the left-handed experimental group (LTG), statistically significant improvements were identified in five out of six analyzed variables: anterior reach (left foot) (p = 0.00), posterior medial reach (left foot) (p = 0.00), posterior lateral reach (left foot) (p = 0.00), posterior medial reach (right foot) (p = 0.00), and posterior lateral reach (right foot) (p = 0.00). The effect size ranged between small and medium. No significant changes were observed in the control group (CG) after the training intervention. Moreover, for all variables, the time*group interaction is determined. Anterior reach (left foot), posterior medial reach (left foot), posterior medial reach (right foot), and posterior lateral reach (right foot) showed significant interactions (F = 3.04, p = 0.05; F = 3.50, p = 0.03; F = 6.08, p = 0.00; and F = 4.69, p = 0.01). The outcome of this study leads us to a further understanding that if a player were to partake in VR activity, it could show a positive effect on their dynamic balance performance. Full article

The purpose of the present study was to examine the effects of a back squat exercise with unstable load (UN) and traditional free-weight resistance (FWR) on subsequent countermovement jump (CMJ) performance. After familiarisation, thirteen physically active males with experience in resistance training visited the laboratory on two occasions during either experimental (UN) or control (FWR) conditions separated by at least 72 h. In both sessions, participants completed a task-specific warm-up routine followed by three maximum CMJs (pre-intervention; baseline) and a set of three repetitions of either UN or FWR back squat exercise at 85% 1-RM. During the UN condition, the unstable load was suspended from the bar with elastic bands and accounted for 15% of the total load. Post-intervention, three maximum CMJs were performed at 30 s, 4 min, 8 min and 12 min after the last repetition of the intervention. The highest CMJ for each participant was identified for each timepoint. No significant increases (p > 0.05) in jump height, peak concentric power, or peak rate of force development (RFD) were found after the FWR or UN conditions at any timepoint. The lack of improvements following both FWR and UN conditions may be a consequence of the low percentage of unstable load and the inclusion of a comprehensive task-specific warm-up. Further research is required to explore higher UN load percentages (>15%) and the chronic effects following the implementation of a resistance training programme. Full article

Football for people with cerebral palsy is a para-sport involving ambulant athletes with impairments, such as hypertonia, ataxia, or athetosis. The objective of the present study was to describe the somatotype of a representative sample of international football players according to different functional profiles of cerebral palsy, including spastic diparesis, athetosis/ataxia, spastic hemiparesis, and minimum impairment criteria, and to compare it with non-disabled football players. A total of 144 international para-footballers and 39 non-disabled footballers participated in the study, and their somatotype was calculated using anthropometric measurements. A Kruskal–Wallis test was used to compare the groups to determine and assess the differences between the different functional profiles, and the analysis of anthropometric variables and body composition showed no differences. Regarding somatotype, a predominance of the mesomorphic component was observed in all subgroups, and differences in somatotype were also found between non-disabled footballers and para-footballers with spastic hemiparesis and minimum impairment criteria. This study suggests that there may be a degree of homogeneity in terms of somatotype among footballers with or without physical impairments, such as hypertonia, athetosis, or ataxia. Furthermore, it provides reference values of international-level para-football players for the different sport classes, which can help coaches and trainers monitor athletes’ physical conditions. Full article

The capacity of laboratory tests to predict competition performance has been broadly researched across several endurance sports. The aim of the present study was to analyse how pool swimming performance can predict the result of the swimming segment in triathlon competitions and compare predictability differences based on competition level and distance. Eighteen male triathletes participated in the study. Three were ranked world-class, ten elite/international level, and five highly trained/national level. A total of sixty-one graded multi-stage swimming tests were conducted. Blood lactate was measured to calculate the following hypothetical predictor variables: speed at lactate threshold 1 (LT1), speed at lactate threshold 2 (LT2), and speed in the last repetition of the test (S_L200). The following data were collected for a total of 75 races: time in the swimming leg (TSL); position after the swimming leg (PSL); time difference with the first triathlete after the swimming leg (DFT); and final race position. The race levels were divided according to participant levels as follows: world series (WS) (n = 22); World Cup (WC) (n = 22); Continental Cup (CC) (n = 19); national championship (N) (n = 5); and local race (L) (n = 5). Based on distance, they were divided into Olympic distance (OD) (n = 37) and sprint distance (SD) (n = 38). A moderate to strong positive association was found between LT1, LT2, S_L200 and PSL and TSl at all race levels except for the SD CC, SD WC, and OD CC races, where no or weak-to-moderate correlations were found. The present study demonstrated that performance measured in a graded multi-stage pool lactate test can predict performance in a triathlon swimming segment. This finding is highly useful for coaches as it can help them to obtain a reliable measure of the triathlete’s specific capabilities in the swimming leg. Full article

Calf injuries are common in professional football; thus, the establishment of reliable and time-efficient methods of measuring the peak force capabilities of the plantar flexors with equipment that is accessible to football practitioners is valuable. In this study, we determined the preliminary reliability and feasibility of a new test, termed the kneeling isometric plantar flexion test (KIPFT), for footballers. Twenty-one male youth footballers (age = 17.8 ± 1.1 years, height = 182 ± 5 cm, weight = 77.6 ± 5.9 kg) from English League One football clubs completed three trials of the KIPFT on a wireless force plate at the end (2022–2023) and start (2023–2024) of the season. The within-session reliability of the peak force (relative to body weight) was good–excellent for both limbs and both occasions. On average, performance of the KIPFT took just over 1 min per limb and ~2 min to set up. The peak force values were larger for the non-dominant limbs only at the start versus the end of the season, but there were no between-limb differences. From these results, it was determined that (1) the KIPFT is feasible, (2) a minimum of 32 footballers would be required to establish its between-session reliability with ≥80% statistical power and (3) large-cohort normative data for the KIPFT may be best collected at the start of the football season. Full article

In the face of an increasingly aging population, nurses have to design and implement programs aimed at the elderly in order to keep them healthy and maintain their quality of life. Structured physical exercise and overall physical activity play a major role in maintaining an active lifestyle, improving health, preventing disease, and helping to maintain older people’s quality of life. To investigate the importance of implementing physical exercise programs for the older person in the community, taking into account the perspective of the rehabilitation nurse specialist, this is a qualitative, exploratory, and descriptive study with nine rehabilitation nurses from various regions of Portugal who have experience of implementing physical exercise programs with the elderly. This study used semi-structured interviews, one of the most common data collection procedures in social and health research. Content analysis was used to analyze the data. The study received a positive opinion from the Ethics Committee. The participants’ perspectives focused on the following subjects: “Physical exercise program for the elderly in the community”, “Importance of physical exercise in the rehabilitation of the elderly in the community”, “People’s adherence to the programs”, “Gains in health resulting from the implementation of these strategies” and “Gains from group activities”. A set of indicators emerged from the analysis. Nurses recognize the importance of using structured physical exercise programs adjusted to the rehabilitation of the older person, with gains in promoting active and healthy aging. Full article

Volleyball is an intermittent team sport that requires specific anthropometrical and physical characteristics for winning performance. The present study aimed to evaluate the maturity status of the young male players of eight volleyball teams, and to observe differences in anthropometric characteristics and body composition. Ninety-four male adolescent volleyball players were recruited during a national tournament carried out in Treviso (Italy). Anthropometric characteristics such as weight, stature, skinfold thicknesses, circumferences and diameters, and bioelectrical impedance were measured. The biological maturation was estimated for all players. Each team was classified as a higher or lower lever according to its tournament ranking. A two-way ANOVA compared team levels and players’ maturity status. Considering the maturity offset, 62 boys were classified as “on time”, 20 as “late”, and 12 as “early”. Three clubs presented many boys with “early” as the maturity offset, and two of these finished the tournament in the first position. Young volleyball players classified as “early” seemed to show anthropometric characteristics linked to better performance at the tournament (higher height, upper arm and calf muscle area, fat mass percentage, and total fat-free mass). The results of the present study could have practical implications for talent selection, but further studies are needed to better evaluate the effect of maturity status on the characteristics of volleyball players. Full article

The purpose of this study was to investigate the correlation between the reactive strength index (RSI) using the drop jump (DJ) and the isometric rate of torque development (RTD) with weightlifting performance in national-level weightlifters. Seven male weightlifters (age: 28.3 ± 5.7 years, body mass: 80.5 ± 6.7 kg, body height: 1.73 ± 0.07 m) participated in this study. Measurements were performed 2 weeks prior to the national championship and included the countermovement jump (CMJ), the squat jump (SJ), the DJ from three different drop heights (20, 30, and 40 cm), and the isometric peak torque (IPT) and RTD. Performance in CMJ and SJ was significantly correlated with weightlifting performance (r ranging from 0.756 to 0.892). Significant correlations were found between weightlifting performance with DJ contact time (r ranging from −0.759 to −0.899) and RSI (r ranging from 0.790 to 0.922). Moreover, the best RSI was significantly correlated with the snatch (r = 0.921, p = 0.003) and total performance (r = 0.832, p = 0.020). Small to very large correlations were found between IPT and RTD with weightlifting performance (r ranging from 0.254 to 0.796). These results suggest that RSI and contact time variables from DJ may predict weightlifting performance in well-trained weightlifters. Additionally, IPT and RTD may provide useful insights into the neuromuscular fitness condition of the weightlifter. Full article

This work aimed to analyze the relationships between maturity offset, anthropometric variables and the vertical force–velocity profile in youth (12–18 years old) male basketball players. The vertical force–velocity profile was measured in 49 basketball players, grouped in competitive-age categories, i.e., under 14, 16 and 18 years of age (U-14, U-16 and U-18, respectively). A bivariate correlational analysis was carried out between maturity offset, anthropometric variables (height, body mass, % fat, muscle mass, bone mass and body mass index (BMI)) and vertical force–velocity profile (theoretical maximal force [F0], theoretical maximal velocity [V0], theoretical maximal power [Pmax], force–velocity imbalance [Fvimb] and force–velocity profile orientation). The results showed significant correlations (p < 0.05) between Fvimb and maturity offset at early ages of training (12–15 years). The anthropometric profile was correlated (p < 0.05) with F0 in U-14, V0 in U-16, and Pmax in U-18 basketball players. The current findings suggest a relationship between the vertical force–velocity imbalance and maturity offset and the main vertical force–velocity profile variables. The vertical force–velocity profile is hypothesized as a useful index to correct vertical force–velocity deficits according to the maturity offset of male basketball players. Full article

Femoroacetabular impingement (FAI) is a common source of hip pain affecting a wide range of subjects. In this work, we assessed two tests, namely the balance test and the MuscleLab test, in comparison with the flexion–abduction–external rotation (FABER) and flexion–adduction–internal rotation (FADIR) tests, in order to evaluate the functionality of the neural–musculoskeletal system of the subjects affected by FAI based on the measurement of biomechanical parameters. Our goal was to investigate the early detection of an altered hip joint and to monitor pathology progression over time. A total of 52 subjects, 29 females and 23 males, with an average age of 42 ± 13 years presenting hip impingement diagnosed using X-ray, were enrolled. Twenty-eight patients without signs of hip impingements were used as the control group. The balance test, which evaluates the capacity of a person to keep the orthostatic position against terrestrial gravity, and the MuscleLab test, which measures the force and power generated by active muscles during a movement, as well as FABER and FADIR tests, were performed in each subject. The balance and MuscleLab tests presented 100% sensitivity and higher sensitivity in FAI diagnosis, with 72.9% and 70.4%, respectively, in comparison with those obtained using FABER and FADIR tests, with 59.6% and 67.3%, respectively. The evaluation of the neural–musculoskeletal system using the balance and MuscleLab tests can help in the early detection of the severity of hip impingements and the assessment of non-operative treatments used over time. Full article

Gait variability (GV) is a crucial measure of inconsistency of muscular activities or body segmental movements during repeated tasks. Hence, GV might serve as a relevant and sensitive measure to quantify adjustments of walking control. However, it has not been clarified whether GV is associated with walking speed, a clarification needed to exploit effective better bilateral coordination level. For this aim, fourteen male students (age 22.4 ± 2.7 years, body mass 74.9 ± 6.8 kg, and body height 1.78 ± 0.05 m) took part in this study. After three days of walking 1 km each day at a self-selected speed (SS) on asphalt with an Apple Watch S. 7 (Apple^TM, Cupertino, CA, USA), the participants were randomly evaluated on a treadmill at three different walking speed intensities for 10 min at each one, SS − 20%/SS + 20%/ SS, with 5 min of passive recovery in-between. Heart rate (HR) was monitored and normalized as %HR_max, while the rate of perceived exertion (RPE) (CR-10 scale) was asked after each trial. Kinematic analysis was performed, assessing the Contact Time (CT), Swing Time (ST), Stride Length (SL), Stride Cycle (SC), and Gait Variability as Phase Coordination Index (PCI). RPE and HR increased as the walking speed increased (p = 0.005 and p = 0.035, respectively). CT and SC decreased as the speed increased (p = 0.0001 and p = 0.013, respectively), while ST remained unchanged (p = 0.277). SL increased with higher walking speed (p = 0.0001). Conversely, PCI was 3.81 ± 0.88% (high variability) at 3.96 ± 0.47 km·h⁻¹, 2.64 ± 0.75% (low variability) at SS (4.94 ± 0.58 km·h⁻¹), and 3.36 ± 1.09% (high variability) at 5.94 ± 0.70 km·h⁻¹ (p = 0.001). These results indicate that while the metabolic demand and kinematics variables change linearly with increasing speed, the most effective GV was observed at SS. Therefore, SS could be a new methodological approach to choose the individual walking speed, normalize the speed intensity, and avoid a gait pattern alteration. Full article

The aim of this study was to measure the effects on three-planar active cervical range of motion (ACROM) and self-perceived pain of elastic taping (ET) application in the cervical area. Thirty participants (n: 22-M and 8-F, age 35.4 ± 4.4 years; body height 173.1 ± 8.4 cm; body mass 73.5 ± 12.8 kg) in the study group (SG) and twenty participants (n: 11-M and 9-F, age 32.6 ± 3.9 years; body height 174.9 ± 10.9 cm; body mass 71.2 ± 12.9 kg) in the control group (CG) were recruited. All subjects had neck and cervical pain in baseline condition. Each group performed an ACROM test and measured the perceived pain in the neck based on the Numerical Rating Scale (NRS 0--10, a.u.) at the baseline (T0), after 20′ from the ET application (T1), and after three days of wearing the ET application (T2). Between T0 and T1, an ET was applied to the cervical area of the SG participants. Statistical analysis did not show any significant change in CG in any measurement session for ACROM and neck pain parameters. Conversely, the SG showed significant improvements for ACROM rotation to the left (T0 64.8 ± 7.7°–T2 76.0 ± 11.1° p < 0.000) and right (T0 66.0 ± 11.9°–T2 74.2 ± 9.6° p < 0.000), lateral inclination to the left (T0 37.5 ± 6.9°–T2 40.6 ± 10.8° p < 0.000) and right (T0 36.5 ± 7.9°–T2 40.9 ± 5.2° p < 0.000), extension (T0 47.0 ± 12.9°–T2 55.1 ± 12.3° p < 0.001), and flexion (T0 55.0 ± 3.6°–T2 62.9 ± 12.0° p < 0.006). A significant decrease was also measured in SG for pain NRS between T0 and T2 (T0 7.5 ± 1.0°–T1 5.5 ± 1.4–T2 1.4 ± 1.5° p < 0.000). In conclusion, a bilateral and symmetrical ET cervical application is useful to enhance multiplanar ACROM and reduce subjective self-perceived cervical pain when it is needed. Based on the evidence, the use of ET on the neck is recommended for managing neck motion restrictions and pain in adult individuals. Full article

Muscle injuries and subsequent reinjuries significantly impact athletes, especially in football. These injuries lead to time loss, performance impairment, and long-term health concerns. This review aims to provide a comprehensive overview of the current understanding of muscle reinjuries, delving into their epidemiology, risk factors, clinical management, and prevention strategies. Despite advancements in rehabilitation programs and return-to-play criteria, reinjury rates remain alarmingly high. Age and previous muscle injuries are nonmodifiable risk factors contributing to a high reinjury rate. Clinical management, which involves accurate diagnosis, individualized rehabilitation plans, and the establishment of return-to-training and return-to-play criteria, plays a pivotal role during the sports season. Eccentric exercises, optimal loading, and training load monitoring are key elements in preventing reinjuries. The potential of artificial intelligence (AI) in predicting and preventing reinjuries offers a promising avenue, emphasizing the need for a multidisciplinary approach to managing these injuries. While current strategies offer some mitigation, there is a pressing need for innovative solutions, possibly leveraging AI, to reduce the incidence of muscle reinjuries in football players. Future research should focus on this direction, aiming to enhance athletes’ well-being and performance. Full article

Multiple sclerosis is a disease that concerns a growing number of people, especially females. There are different interventions proposed for this population, and physical activity is one of them. A proper and well-structured physical activity program can be a cheap, feasible, and practical instrument to help this population improve their quality of life. Consequently, the present study aimed to analyze, through an umbrella review, published articles to evaluate the protocols and the effect of intervention on different types of multiple sclerosis and eventually to propose a standardized intervention for this population. Systematic reviews and meta-analyses of randomized controlled trials on multiple sclerosis and physical activity effects were searched for on the electronic databases PubMed, Web of Science, and Scopus up to 22 December 2022. The quality of the studies included was determined and the results were narratively analyzed. The included studies present heterogeneity in the population, in the study design and protocols, and in the outcomes evaluated. Most of the studies detected positive outcomes on the physical function of people with multiple sclerosis. This study highlights the necessity of future studies on a population with similar characteristics, adopting similar protocols to evaluate their feasibility and validity to make physical intervention prescribed as a medicine. Full article

The purpose of this study was to investigate and compare the passive joint range of motion (PROM) and muscle strength in prepubertal rhythmic gymnasts (RGs), artistic gymnasts (AGs), and a control group (CG) of the same age. A total of 54 prepubertal girls were divided into three groups: 18 RGs (age 11.14 ± 0.7, height 142.6 ± 5.81, and body mass 31.2 ± 3.63); 18 AGs (age 11.27 ± 0.99, height 139.6 ± 5.85, and body mass 31.7 ± 3.21), and 18 school girls who are defined as CG (age 10.55 ± 0.42, height 145.33 ± 6.95, and body mass 42.1 ± 8.21) participated in the study. All athletes were elites and participated in national competitions. The CG participated only in their school physical education program. Isokinetic peak torques were measured using an isokinetic dynamometer (Cybex II) at 60, 180, and 300°·sec⁻¹. Body mass index was greater in the CG compared to RGs and AGs (p < 0.001). PROM in cervical extension in RG was significantly higher compared to the AG and CG (p < 0.001). The athlete groups, RG and AG, showed significantly greater PROM in knee flexion (p < 0.001), hip flexion (p < 0.001), and hip abduction (p < 0.05) compared to CG. PROM in hip flexion was different between the left and right leg in RGs. The relative muscle strength of the quadriceps in the RG and AG was significantly greater compared to CG (p < 0.001 and p < 0.01 respectively). Gymnastics training in prepubertal ages can improve neuromuscular function and increase the relative muscle strength. Therefore, it is essential to note that when evaluating children within the developmental ages, especially those involved in sports, the type of muscle strength to be assessed should be specified. Full article

The Army Combat Fitness Test (ACFT) is a multi-event assessment battery designed to determine the combat readiness of U.S. Army personnel. However, for Reserve Officers’ Training Corps (ROTC) programs the logistical demands of collegiate life make repeated administration of the ACFT challenging. The present study sought to design and evaluate a single, multimodal exercise tolerance test (METT) capable of serving as a time-efficient proxy measure of combat readiness. Methods: Using a formal instrument design process, we constructed the METT to mimic the demands of the ACFT and assessed its reliability, validity, and responsiveness. Results: The METT demonstrates minimal measurement error (i.e., a 2% coefficient of variation), concurrent validity with the ACFT (R² = 0.327, F = 10.67, p < 0.001), the ability to classify cadets who may be at-risk for failing the ACFT (X² = 8.16, p = 0.017, sensitivity = 0.878, specificity = 0.667), and appropriate change following a training intervention (5.69 ± 8.9%). Conclusions: The METT has the potential to provide a means to monitor progress, identify areas for improvement, and guide informed decision-making regarding individualization of cadet combat training plans. Full article

This study was aimed at comparing the force–velocity relationship during cycling and arm cranking in males and females. Thirty-two male and twenty-two female healthy volunteers performed a force–velocity test on a cycle ergometer and a cranking ergometer in a randomly selected order. The theoretical values of the maximum force at zero speed (F₀) and the maximum velocity at zero braking force (v₀) for the lower and upper limbs were determined, and the maximum anaerobic power (Pmax) was calculated from the individual force–velocity relationship. The Pmax and F₀ of the upper limbs related to the lower limbs correspond to 78.2 ± 14.3% and 80.1 ± 17.3% in men and 65.5 ± 12.5% and 74.5 ± 6.5% in women, respectively. The theoretical maximum velocity v₀ of the upper limbs to the lower limbs attained 129.1 ± 29.0% in men and 127.4 ± 26.4% in women. The results of the study can serve as reference data for the force–velocity characteristics of the upper and lower limbs of male and female athletes. The results can be used both in training and rehabilitation programs, where the starting point is the objectification of possible strength deficits in various areas of the force–velocity characteristic spectrum of the muscles of the upper and lower limbs. Full article

In recent years, much effort has been made to reduce the injury rate in combat sports. However, the question remains to what extent these measures are effective. Analysis of studies could provide evidence of the effectiveness of measures aimed at reducing the incidence of injuries. This scoping review aims (1) to map research articles dealing with the effectiveness of proper use of protective measures in reducing the incidence of injuries in combat sports; (2) to investigate to what extent the proper use of protective measures and compliance with sports rules help to reduce the incidence of injuries in combat sports; and (3) to identify gaps in the existing literature and suggest future research on this topic. The literature search was conducted on articles published between 2010 and 2023. The main inclusion criteria were studies investigating the effect of sports rules and protective equipment used during training or competition in combat sports on reducing the incidence of injuries. After meeting the criteria, only seven articles from boxing, karate, and taekwondo were included in this study. Results showed that mandatory head guards, along with modern thicker gloves, significantly reduced the rate of knockouts (KOs) and head injuries in boxing despite an increase in the number of head blows. However, the number of facial cuts increased significantly due to the removal of head guards as a piece of mandatory equipment. The use of mouth guards has significantly reduced the number of oral injuries. Changes in rules, such as shortening the duration of bouts, along with the introduction of greater competencies of referees in the supervision of bouts (the standing count, outclassed rule, and medical stops) have helped to reduce the rate of injuries in boxing. The application of a computerised scoring system also contributed to the rate of injuries reduction. The increase in the number of weight divisions had the same effect on U21 karate athletes. However, a higher incentive to attack the head area in taekwondo did not increase the incidence of injuries in youth athletes. It can be concluded that the proper use of protective measures (head and mouth guards) in combination with the rules established for health protection (higher competencies of referees and more weight divisions in competitions) effectively reduces the occurrence of injuries in combat sports. In all Olympic combat sports, the injury incidence should be regularly assessed using the Injury Incidence Rate (IIR) per 1000 min exposures (MEs). Nonetheless, further studies are needed to monitor how established rules (e.g., prohibited behaviour) affect the IIRs. Full article

This study aimed to associate body composition with fractional oxygen extraction at rest in healthy adult men. Fourteen healthy adults (26.93 ± 2.49 years) from Chile participated. Body composition was assessed with octopole bioimpedance, and resting muscle oxygenation was evaluated in the vastus lateralis quadriceps with near-infrared spectroscopy (NIRS) during a vascular occlusion test, analyzing the muscleVO₂, resaturation velocity during reactive hyperemia via the muscle saturation index (%TSI), and the area above the curve of HHb (AACrep). It was observed that the total and segmented fat mass are associated with lower reoxygenation velocities during hyperemia (p = 0.008; β = 0.678: p = 0.002; β = 0.751), and that the total and segmented skeletal muscle mass are associated with higher reoxygenation velocities during hyperemia (p = 0.020; β = −0.614: p = 0.027; β = −0.587). It was also observed that the total and segmented fat mass were associated with a higher area above the curve of HHb (AACrep) during hyperemia (p = 0.007; β = 0.692: p = 0.037; β = 0.564), and that total and segmented skeletal muscle mass was associated with a lower area above the curve of HHb (AACrep) during hyperemia (p = 0.007; β = −0.703: p = 0.017; β = −0.632). We concluded that fat mass is associated with lower resaturation rates and lower resting fractional O₂ extraction levels. In contrast, skeletal muscle mass is associated with higher resaturation rates and fractional O₂ extraction during reactive hyperemia. The AACrep may be relevant in the evaluation of vascular adaptations to exercise and metabolic health. Full article

Our aim was to evaluate musculoskeletal discomfort and the lifestyle of military police officers of administrative and tactical force departments. Military police officers were distributed into two groups: administrative (Adm, n = 15) and tactical force (TF, n = 16) departments. Their lifestyle was assessed using the Fantastic Lifestyle questionnaire. Moreover, physical activity quantification was assessed using the International Physical Activity questionnaire, and musculoskeletal discomfort was quantified using the Corlett diagram. The mean total time of physical activity was 546 ± 276 min per week. No differences (p = 0.0832) were found between the Adm (454 ± 217 min) and TF (623 ± 301 min) groups. Concerning lifestyle, in general the sample presented very good (42%) and good (42%) style classification. For this parameter, no significant differences were found, but only a tendency was discovered (x²: 7.437; p = 0.0592); indeed, the TF presented a better classification (63%) of very good, compared to the Adm (53%) of good. No differences (p > 0.05) were found in musculoskeletal perception of discomfort between the right and left sides (p > 0.05) for all police officers and between the Adm and FT groups (p > 0.05). Military police officers showed high and moderate risk for waist circumference and waist-to-hip ratio, respectively; however, lifestyle and total time of physical activity were considered adequate without differences between military administrative and tactical force sectors. Full article

Reliable fitness tests with low day-to-day and trial-to-trial variation are a prerequisite for tracking a player’s performance or for identifying meaningful changes in training interventions. The present study examined the inter- and intra-session reliability of 30 m linear speed with and without ball possession as well as the reliability of a specific performance index of pubertal soccer players. A total of 40 pubertal (14.87 ± 1.23 years old) male soccer players performed two testing sessions (test–retest) separated by 72 h. Both testing sessions included a protocol consisting of two maximal trials of 30 m linear speed with and without ball possession. A performance index, indicating the difference between the two speed tests, was also calculated using two different equations (delta value and percentage value). The relative and absolute inter-session reliabilities were good/high for all testing variables (ICC = 0.957–0.995; SEM% = 0.62–8.83). There were also good/high relative and absolute intra-session reliabilities observed for all testing variables (ICC = 0.974–0.987; SEM% = 1.26–6.70%). According to the Bland–Altman plots, the differences between test–retest and trials for all observations were within the defined 95% limits of agreement. The reliable testing protocols and performance index for the evaluation of linear speed with and without ball possession, observed in this study, may be used in speed monitoring and training planning of pubertal soccer players. Full article

Intense, long exercise can increase oxidative stress, leading to higher levels of inflammatory mediators and muscle damage. At the same time, fatigue has been suggested as one of the factors giving rise to delayed-onset muscle soreness (DOMS). The aim of this study was to investigate the efficacy of a specific electrical stimulation (ES) treatment (without elicited muscular contraction) on two different scenarios: in the laboratory on eleven healthy volunteers (56.45 ± 4.87 years) after upper limbs eccentric exercise (Study 1) and in the field on fourteen ultra-endurance athletes (age 47.4 ± 10.2 year) after an ultra-running race (134 km, altitude difference of 10,970 m+) by lower exercising limbs (Study 2). Subjects were randomly assigned to two experimental tasks in cross-over: Active or Sham ES treatments. The ES efficacy was assessed by monitoring the oxy-inflammation status: Reactive Oxygen Species production, total antioxidant capacity, IL-6 cytokine levels, and lactate with micro-invasive measurements (capillary blood, urine) and scales for fatigue and recovery assessments. No significant differences (p > 0.05) were found in the time course of recovery and/or pre–post-race between Sham and Active groups in both study conditions. A subjective positive role of sham stimulation (VAS scores for muscle pain assessment) was reported. In conclusion, the effectiveness of ES in treating DOMS and its effects on muscle recovery remain still unclear. Full article

Older adults often suffer an accidental fall when navigating challenging surfaces during common locomotor tasks, such as walking and ascending stairs. This study examined the effect of slick and uneven surfaces on lower limb joint work in older and younger adults while walking and ascending stairs. Fifteen young (18–25 years) and 12 older (>65 years) adults had stance phase positive limb and joint work quantified during walking and stair ascent tasks on a normal, slick, and uneven surface, which was then submitted to a two-way mixed model ANOVA for analysis. The stair ascent required greater limb, and hip, knee, and ankle work than walking (all p < 0.001), with participants producing greater hip and knee work during both the walk and stair ascent (both p < 0.001). Surface, but not age, impacted positive limb work. Participants increased limb (p < 0.001), hip (p = 0.010), and knee (p < 0.001) positive work when walking over the challenging surfaces, and increased hip (p = 0.015), knee (p < 0.001), and ankle (p = 0.010) work when ascending stairs with challenging surfaces. Traversing a challenging surface during both walking and stair ascent tasks required greater work production from the large proximal hip and knee musculature, which may increase the likelihood of an accidental fall in older adults. Full article

The goal of this study was to investigate the effects of photobiomodulation therapy (PBMT) on performance, oxygen uptake (VO₂) kinetics, and lower limb muscle oxygenation during three successive time-to-exhaustions (TTEs) in cyclists. This was a double-blind, randomized, crossover, placebo-controlled trial study. Sixteen cyclists (~23 years) with a cycling training volume of ~460 km/week volunteered for this study. In the first session, cyclists performed a maximal incremental test to determine maximal oxygen uptake and maximal power output (PO_MAX). In the following sessions, cyclists performed three consecutive TTEs at PO_MAX. Before each test, PBMT (135 J/thigh) or a placebo (PLA) was applied to both thighs. VO₂ amplitude, O₂ deficit, time delay, oxyhemoglobin (O₂Hb), deoxyhemoglobin (HHb), and total hemoglobin (tHb) were measured during tests on the right vastus lateralis. The PBMT applied before three successive TTE increased performance of the first and second TTE (~10–12%) tests, speed of VO₂ and HHb kinetics during the first test, and increased peripheral muscle oxygenation (increase in HHb and tHb) in the first and second exhaustion tests. However, the PBMT effects were attenuated in the third TTE, as performance and all the other outcomes were similar to the ones from the PLA intervention. In summary, PBMT application increased the first and second successive TTEs, speed of VO_2, and muscle oxygenation. Full article

Current metrics like baseline heart rate (HR) and HR recovery fail in predicting overtraining (OT), a syndrome manifesting from a deteriorating autonomic nervous system (ANS). Preventing OT requires tracking the influence of internal physiological loads induced by exercise training programs on the ANS. Therefore, this study evaluated the predictability of a novel, exercise cardiac load metric on the deterioration of the ANS. Twenty male American football players, with an average age of 21.3 years and body mass indices ranging from 23.7 to 39.2 kg/m² were included in this study. Subjects participated in 40 strength- and power-focused exercise sessions over 8 weeks and wore armband monitors (Warfighter Monitor, Tiger Tech Solutions) equipped with electrocardiography capabilities. Exercise cardiac load was the product of average training HR and duration. Baseline HR, HR variability (HRV), average HR, and peak HR were also measured. HR recovery was measured on the following day. HRV indices assessed included the standard deviation of NN intervals (SDNN) and root mean square of successive RR interval differences (rMSSD) Linear regression models assessed the relationships between each cardiac metric and HR recovery, with statistical significance set at α < 0.05. Subjects were predominantly non-Hispanic black (70%) and aged 21.3 (±1.4) years. Adjusted models showed that exercise cardiac load elicited the strongest negative association with HR recovery for previous day (β = −0.18 ± 0.03; p < 0.0000), one-week (β = −0.20 ± 0.03; p < 0.0000) and two-week (β = −0.26 ± 0.03; p < 0.0000) training periods compared to average HR (βetas: −0.09 to −0.02; p < 0.0000) and peak HR (βetas: −0.13 to −0.23; p < 0.0000). Statistically significant relationships were also found for baseline HR (p < 0.0000), SDNN (p < 0.0000) and rMSSD (p < 0.0000). Exercise cardiac load appears to best predict ANS deterioration across one- to two-week training periods, showing a capability for tracking an athlete’s physiological tolerance and ANS response. Importantly, this information may increase the effectiveness of exercise training programs, enhance performance, and prevent OT. Full article

Inertial sensors (IMUs) have been recently widely used in exercise and rehabilitation science as they can provide reliable quantitative measures of range of motion (RoM). Moreover, the pressure pain threshold (PPT) evaluation provides an objective measure of pain sensation in different body areas. The aim of this study was to evaluate the efficacy of physiotherapy treatment in people with adhesive capsulitis in terms of RoM and pain improvement measured by IMUs and the PPT. A combined prospective cohort/cross-sectional study was conducted. Nineteen individuals with adhesive capsulitis (10/19 females, 54 ± 8 years) and nineteen healthy controls (10/19 females, 51 ± 6 years) were evaluated for active glenohumeral joint RoM and PPT on shoulder body areas. Then, individuals with adhesive capsulitis were invited to 20 sessions of a physiotherapy protocol, and the assessments were repeated within 1 week from the last session. The range of motion in the flexion (p = 0.001) and abduction (p < 0.001) of the shoulder increased significantly after the physiotherapy protocol. Similarly, the PPT was found to increase significantly in all the assessed shoulder body areas, leading to no significant differences compared to the healthy controls. IMU and PPT assessments could be used to evaluate the efficacy of physical therapy in people with adhesive capsulitis. Full article

Injury in sports is an occurrence that prevents athletes from participating in training and competitions and has an incidence of 8.1 injuries/1000 h of practice. This translates into a cost and also into danger, especially if the event is repeated, for the health of the athlete; the injury certainly has a multifactorial causality. On the other hand, having instruments that can represent an alarm could be helpful for those involved in sports science. We used a specifically designed instrument, presented in a previous work, which shows excellent reliability and repeatability in measuring the strength of the knee flexors and extensors to test 107 players belonging to three different teams playing in the Italian Serie A. We took three measurements, beginning of the season, mid-season, and close to the end of the season. This retrospective study on 107 professional soccer players demonstrates that isometric force-related parameters of the knee extensors and flexors are associated with the risk of injury to lower limbs. Logistic regression evidenced a significant correlation between the parameter indicating the imbalance of the force between the flexors of the two limbs ($p\le 0.05$, OR = 1.089) and the occurrence of injuries. Survival analyses ($p\le 0.001)$ evidenced a correlation between the population survival time and the injury incidence. We demonstrated that the analysis of the strength imbalance is correlated with injury occurrence, but it is well known that sports injuries are a multifactorial event; so, they cannot be predicted by only one parameter. However, the method proposed in this paper could represent a useful tool for sport scientists. Full article

The objective of the study was to examine the effects of Pilates exercise training combined with walking on cardiorespiratory fitness, functional capacity, and disease activity in patients with non-radiologically confirmed axial spondylitis (nr-axSpA). Thirty patients with nr-axSpA (seven women (90%), with a mean age of 46.07 ± 10.48 years old and C-reactive protein (CRP) 2.26 ± 2.14 mg/L) were randomly divided into two groups: A (n₁ = 15 patients) and B (n₂ = 15 patients). Group A followed a 6-month home-based Pilates exercise training program, while Group B remained untrained until the end of the study. A cardiopulmonary exercise test (CPET), timed up and go test (TUG), five times sit-to-stand test (5×STS), sit-and-reach test (SR), back scratch test for the right (BSR) and the left arm (BSL), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and Ankylosing Spondylitis Disease Activity Score (ASDAS) were applied to all patients, both at the beginning and at the end of the study. After 6 months, Group A showed higher values in exercise time by 37.41% (p = 0.001), higher peak oxygen uptake (VO₂peak) by 25.41% (p = 0.01), a higher ratio between oxygen uptake and maximum heart rate (VO₂/HRmax) by 14.83% (p = 0.04), and higher SR by 18.70% (p = 0.007), while lower values were observed in TUG by 24.32% (p = 0.001), 5×STS by 12.13% (p = 0.001), BASDAI score by 20.00% (p = 0.04) and ASDAS score by 23.41% (p = 0.03), compared to Group B. Furthermore, linear regression analysis showed a positive correlation in Group A between BASDAI and 5×STS (r = 0.584, p = 0.02), BASDAI and TUG (r = 0.538, p = 0.03), and ASDAS and 5×STS (r = 0.538, p = 0.03), while a negative correlation was found between BASDAI and VO₂peak (r = −0.782, p < 0.001), ASDAS and SR (r = −0.548, p = 0.03), and ASDAS and VO₂peak (r = −0.659, p = 0.008). To sum up, cardiorespiratory fitness, functional capacity, and disease activity improved after a long-term Pilates exercise training program in patients with nr-axSpA. Full article