Validity and reliability of the My Jump 2 app for detecting interlimb asymmetry in young female basketball players.

Introduction: The aim of this study was to examine the validity and reliability of the My Jump 2 app for the assessment of interlimb jump asymmetry in young female basketball players. Methods: Nine athletes (age 15 ± 0.9 years; weight 62.9 ± 5.8 kg; height 173.6 ± 6.1 cm) performed single-leg drop jumps (DJs) and both-leg drop jumps on a force plate (Kistler Quattro jump) and were simultaneously recorded on two smartphones using the My Jump 2 app. Jump height from flight time and contact time data were statistically analyzed to evaluate the validity of two different camera settings, drop jump performance, and interlimb jump asymmetry in basketball players. The testing was repeated after 1 week for test retest reliability. Results: High test-retest reliability [intraclass correlation coefficient (ICC) > 0.88] was observed in DJ height. High correlation between the force plate and the My Jump 2 app was observed in DJ height (r = 0.99) and DJ contact time (r = 0.98). For the interlimb jump height asymmetries, mean differences were 0.6 percentages for the My Jump 2 app and the force plate, respectively (p = 0.77). Inter-device reliability revealed almost perfect correlation for the DJ height (ICC = 0.99, r = 0.98). Conclusion: The My Jump 2 app is a valid and reliable tool to assess drop jump performance and interlimb asymmetry in young female basketball players.

How Does a 12-Week Physical Exercise Program Affect the Motor Proficiency and Cognitive Abilities of Overweight and Normal-Weight Preschool Children?

The objective of this research was to examine a 12-week exercise program and its impact on the motor proficiency and cognitive abilities of preschool children with overweight and normal weight. The study involved a total of 71 participants who were preschool children enrolled in a longitudinal study. Body mass index (BMI) was determined by measuring body height and weight, and the nutritional status of the children was assessed using the World Health Organization's (WHO) criteria. Motor proficiency encompasses both motor abilities and motor skills, and the assessment of motor abilities was conducted using subtests from the Bruininks-Oseretsky Test of Motor Proficiency (BOT-2). These subtests measured fine motor integration, manual dexterity, balance, and bilateral coordination. The evaluation of motor skills involved the utilization of the Test of Gross Motor Development (TGMD-2), which examines both locomotor skills and manipulative skills. Cognitive abilities were assessed using the School Maturity Test (TZS). All participants, regardless of weight status, took part in a 12-week physical exercise program. According to the World Health Organization's criteria, 52 children (73.2%) were categorized as having a normal weight, while 19 children (26.8%) were classified as overweight. These findings indicate that every fourth child in the study was overweight. Using a statistical analysis called SPANOVA (2 × 2, group × time), differences were observed in three out of eleven variables. Specifically, there were significant differences in two motor skill variables: manipulative skills (p = 0.006) and total movement skills (p = 0.014). Additionally, there was a significant difference in one cognitive ability variable: visual memory (p = 0.010). No significant differences were found in the remaining variables. The findings of this study aimed to contribute to the understanding of the potential benefits of regular exercise on motor and cognitive development in preschool children, specifically examining the differences between overweight and normal-weight children. By investigating these effects, the study could provide valuable insights for educators, parents, and health professionals involved in promoting the overall well-being of preschool-aged children. Regular physical exercise has been found to have positive effects on motor and cognitive abilities in both overweight and normal-weight preschool children.

Spasmolytic Activity of Gentiana lutea L. Root Extracts on the Rat Ileum: Underlying Mechanisms of Action.

The roots of Gentiana lutea L. are utilized in the preparation of various beverages and herbal remedies, serving as a traditional remedy for gastrointestinal ailments. The spasmolytic activity that could substantiate the traditional use of G. lutea root had not been investigated. The main objective goal of the study was to determine the validity of its use as a traditional remedy. The extraction of G. lutea root was performed using a 50% hydroethanolic solvent with three different extraction techniques: ultrasound-assisted extraction (UAE), heat-assisted extraction, and percolation. The spasmolytic activity was tested on isolated rat ileum. The mechanism of action was monitored using the models of spontaneous contractions and acetylcholine-, histamine-, CaCl2-, Bay K8644-, L-NAME-, ODQ-, apamin-, BaCl2-, charybdotoxin-, glibenclamide-, TRAM-34-, and quinine-modified contractions. UAE, having the best bioactivity, was further subjected to a liquid-liquid extraction fractionation. HPLC phytochemical analysis was performed for all tested extracts and fractions. Gentian root extracts were rich in secoiridoids, xanthones, and flavonoids. The UAE has shown better results on spontaneous contractions in comparison to its fractions, leading to the more detailed testing of its spasmolytic mechanism of activity. The extract's activity is primarily mediated through intermediate conductance Ca2+-activated K+ channels, ATP-sensitive K+ channels, voltage-sensitive K+ channels, and mechanisms that activate Ca2+ channels. Overall, the G. lutea root shows great potential in the treatment of spasmodic gastrointestinal ailments.

Anaplasma phagocytophilum Encephalitis: A Case Report and Literature Review of Neurologic Manifestations of Anaplasmosis.

Anaplasma phagocytophilum is an obligate intracellular, Gram-negative pathogen, causative agent of Human Granulocytic Anaplasmosis (HGA). HGA usually manifests as a non-specific febrile illness, accompanied by evidence of leucopenia, thrombocytopenia, and an alteration in liver enzymes. Neurologic manifestations of anaplasmosis are rare and rarely reported. We describe a 62-year-old man who developed encephalitis due to an Anaplasma phagocytophilum infection. The patient favorably responded to intravenous doxycycline and recovered without neurological sequela. In the tick endemic area, clinicians should have a high index of suspicion for tick-borne diseases in patients presenting with neurological deficits. A prompt diagnosis and treatment lead to improvements in morbidity and mortality.

Discriminant Analysis Approach in Morphometric Differentiation and Characterization of Serbian Autochthonous Goats.

This study investigated the possibility of using morphometric measurements to differentiate the autochthonous Serbian White goat breed from Saanen and Balkan goats, which were used as sire and dam breeds in its creation. For this purpose, a multivariate discriminant analysis was used. A total of 11 morphometric traits were measured in 98 does of 3 breeds: Saanen (n = 28), Balkan (n = 28), and Serbian White (n = 42), aged 2 to 7 years, in 4 different locations. Univariate analysis of variance revealed a significant difference in body measurements of all three breeds, with Saanen goat being the largest in format and Balkan the smallest. Discriminant analysis extracted six out of eleven tested morphometric traits with the strongest discriminatory power: heart girth, head length, chest depth, head width, pelvic width, and body length. Mahalanobis distances were significant between all three genetic groups. The discriminant function correctly classified 95.24% of the Domestic White goats investigated to their source group. The classification accuracy of the function was cross-validated and indicated an overall success rate of 91.84%. The results of this research showed that there was a clear separation between Serbian White, Saanen, and Balkan goats. The present findings could help a more rapid field assessment of Serbian White goats.

The Influence of Body Composition on Sagittal Plane Posture among Elementary School-Aged Children.

Proper posture, characterized by the appropriate alignment of the cervical, thoracic, and lumbar segments of the spine, enables these regions to maintain their normal curvature. Body composition is recognized as one of the factors that can influence overall postural alignment of the spine. The objective of this study was to determine the influence of the parameters of body composition on the prevalence of postural disorders in the sagittal plane. The cross-sectional study was conducted on 152 children of both genders (78 boys), at a mean age of 11 years ± 6 months. In order to evaluate postural disorders, the Formetric 4D System, a tool manufactured by Diers, Schlangenbad, Germany was used. Based on its output data, the following variables were obtained: hyperkyphosis, hyperlordosis, kypholordosis, flatback, and normal alignment of the body in the sagittal plane. The evaluation of body composition parameters was conducted using the InBody 770 device. To determine how body composition influences the postural status of the spinal column, a discriminant analysis was employed. The results showed that approximately 65.8% of children exhibit various types of postural disorders when assessing the alignment of the spine in the sagittal plane. The most prevalent disorder observed was hyperkyphosis, affecting 34.2% of the subjects, followed by kypholordosis at 16.4%. Moreover, the results demonstrated that body composition significantly influences body posture (p = 0.004). An increase in fat mass corresponds to a deviation from normal body posture, whereas an increase in the percentage of skeletal muscle mass and fat-free mass is associated with a reduction in postural abnormalities in the sagittal plane. Considering the results, it is clear that body composition parameters serve as more reliable predictors of the influence on body posture compared to simply calculating the body mass index. Furthermore, it can be concluded that there are consistent patterns of influence by specific body composition parameters, including fat mass, percentage of skeletal muscle, and fat-free mass, on body posture among children from various climates. These results underscore the significance of implementing strength exercises in children, particularly during periods of rapid growth and development, as a means of preventing and correcting postural disorders.

Case Study on Increasing Breeding Value Estimation Reliability of Reproductive Traits in Serbian Highly Prolific Large White and Landrace Sows.

This study investigated the influence of the degree of connectedness on the reliability of the estimated breeding values (EBVs). The focal trait in the study was the number of piglets born alive (NBA) from sows of the highly prolific Large White and Landrace sows. An analysis included total of 58,043 farrowing's during the 2008-2020 period. BLUP procedure was used to estimate the breeding values for NBA for the three herds separately and after merging all three herds into one herd. The model for EBV estimation included the following fixed factors: parity, genotype, seasons, litter sire, herds, sow age at farrowing, weaning-conception interval, length of previous lactation, and the following random effects: common litter environment, permanent litter environment, and direct additive genetic effect of animal. Heritability values for NBA ranged from 0.048 to 0.097, depending on the data included in the analysis. The connectedness between herds was analysed using the connectedness rating (CR) and the gene flow (GF) methods. CR among the observed herds ranged from 0.245 to 0.994%, depending on the data included. The exchange of genetic material between all three herds was determined using GF method. The high degree of connectedness determined by the CR and GF method had a strong effect on EBV reliability. The average EBV reliability ranged from 0.520 to 0.867, depending on the data included. The increase in average reliability was observed in both cases when the data were added, both in the analysis of average reliability for purebred animals and when crossbreeds were added, where an increase in this value was also observed. The increase in average EBV reliability is a consequence of the greater amount of information included in the joint evaluation. In conclusion, we believe that our research will improve EBV reliability and help in further selection work in the Republic of Serbia.

The effects of post-activation performance enhancement and different warm-up protocols on swim start performance.

This study aimed to examine the effects of post-activation performance enhancement (PAPE) on swim start performance and lower body power performance after different warm-up protocols. Ten male national-level swimmers performed three different warm-ups: (i) a swim-specific warm-up (SW, control protocol); (ii) PAPE (an experimental protocol); and (iii) SW followed by PAPE (SW + PAPE, an experimental protocol). PAPE consisted of performing three series of 5 drop jumps. A repeated-measures ANOVA showed significant differences between the protocols in the swim start performance (F = 8.89; P < 0.001) and countermovement jump (F = 2.22; P = 0.047). SW + PAPE induced greater improvements in swim start time to 15 m (ES = - 0.47, P = 0.017) and entry time (ES = - 1.83, P < 0.001), the countermovement jump reactive strength index modified (ES = - 1.83, P < 0.001), eccentric rate of force development (ES = 0.69, P = 0.047), and index of explosive strength (ES = 0.94, P = 0.005) compared to SW. The current findings of this study indicate that the drop jump PAPE protocol, in addition to SW, is an effective tool because it could improve athletes' capacity for a more efficient swim start and their countermovement jump performance. Furthermore, the results of this study indicate that PAPE induced by drop jumps could be time-efficient and practically applicable in facilities with limited resources.

Speed, Change of Direction Speed, and Lower Body Power in Young Athletes and Nonathletes According to Maturity Stage.

The aim of this study was to establish the role of maturation on the development of physical performance in adolescent athletes and nonathletes. The total studied sample consisted of 231 participants (131 athletes: 72 boys with an average chronological age of 13.53 ± 0.7 and 59 girls with an average chronological age of 11.97 ± 0.8; 100 nonathletes: 47 boys with an average chronological age of 13.73 ± 0.47 and 53 girls with an average chronological age of 11.93 ± 0.33), distributed according to their biological maturity stage (Pre-, Mid-, and Post-Peak Height Velocity [PHV]) and to their gender. The assessment of physical performance was performed using the following tests: Countermovement jump (CMJ), countermovement jump with arm swing (CMJA), squat jump (SJ), five-jump test (5JT), 5 m sprint (5 m), 10 m sprint (10 m), 20 m sprint (20 m), T-test, Zig Zag, and Slalom. The differences in athletes according to biological maturity were identified in all variables except for 5 m (p = 0.33) and Slalom (p = 0.07), while in nonathletes the differences were found in 5JT (p = 0.01), 5 m (p = 0.02), 10 m (p = 0.01), and 20 m (p = 0.01) tests. Additionally, a significant interaction of gender and biological maturity was detected for CMJ (p = 0.03), CMJA (p = 0.01), and Zig Zag (p = 0.05) in athletes. The findings of the current study confirm the importance of maturity status in the assessment of physical performance. As a consequence, a more rational selection of talented athletes could be provided, also enabling the timely development of physical performance in nonathletes as a "window of opportunity".

Lemon balm (Melissa officinalis L.) essential oil and citronellal modulate anxiety-related symptoms - In vitro and in vivo studies.

ETHNOPHARMACOLOGICAL RELEVANCE: Besides psyche-related symptoms, patients with anxiety disorders can have a large number of somatic symptoms as well. Although the treatment of these disorders is mainly focused on resolving their mental component, one cannot neglect the need for the treatment of accompanying somatic symptoms. Melissa officinalis L. (lemon balm), in various formulations, has been extensively used as an ethnomedicinal remedy for the treatment of different psyche-related symptoms, and its use is considered relatively safe. AIM OF THE STUDY: In the present study, the activity of M. officinalis (MO) essential oil was evaluated in several in vitro and in vivo models mimicking or involving anxiety-related somatic symptoms. MATERIALS AND METHODS: To address the effect of MO essential oil on the gastrointestinal and heart-related symptoms accompanying anxiety disorders, in vitro models were utilized that follow the function of the isolated mouse ileum and atria tissues, respectively, after exposure to MO essential oil. Effects of MO essential oil on BALB/c mice motor activity was estimated using the open field, rota-rod, and horizontal wire tests. Additionally, the essential oil was assayed for its potential in inhibiting acetylcholinesterase activity. RESULTS: The performance of mice treated with 25 mg/kg of the oil showed a statistically significant decrease in the motor impairment arising from acute anxiety (open field test), while there was a prolonged latency and a reduction of the frequency of falling from a rotating rod and/or a horizontal wire (signs of muscle weakness/spasms). Concentrations of the essential oil higher than 1 µg/mL were found to inhibit both spontaneous and induced ileum contractions. Moreover, the essential oil and citronellal were found to decrease isolated mouse atria contraction frequency, as well as contraction force. However, the oil was found to be a very weak acetylcholinesterase inhibitor. CONCLUSION: The modulation of anxiety-related symptoms by the oil was found not to be mediated through the inhibition of the acetylcholinesterase, nonetheless, the mechanistic studies involving the ileum and cardiac tissues, revealed that the activity of MO and citronellal might be related to the modification of either voltage-gated Ca2+ channels or muscarinic receptors. Mice locomotion, balance, and muscle strength were not impacted by the essential oil; however, its main constituent, citronellal, was found to exert a certain degree of muscle function inhibition. All these results suggest that the activity of MO essential oil arises from synergistic and/or antagonistic interactions of its constituents, and is not completely dependent on the oil's main constituent.

Curcumin nanoliposomes mitigate wound tissue inflammatory response caused by tooth extraction

Abstract Curcumin is a plant-derived compound with polypharmacological properties that are hampered by its poor solubility, fast degradation, etc. Wound closure complications that follow tooth extraction are numerous, and relatively frequently additional treatment is needed to prevent unwanted process chronification. The present study aims to compare the effects of free and the nanoliposome-encapsulated curcumin on tooth extraction wound closure. The experiments were performed on Wistar rats where both forms of curcumin were applied topically on a tooth extraction wound for seven days. Changes in tissue oxidative stress (malondialdehyde and oxidized proteins concentrations, and catalase activity) and inflammation (nitric oxide levels and myeloperoxidase activity) related parameters were studied three and seven days following the tooth extraction. Also, the extent of pathohistological changes and osteopontin immunohistochemical expression were studied. The obtained results indicate that both forms of curcumin prevent an increase in oxidative stress and inflammation-related parameters in the studied samples at 3-and 7-day time points. Additionally, we found that curcumin diminished tissue inflammatory response and osteopontin expression, while at the same time it caused faster granulation tissue maturation. The encapsulation of curcumin in nanoliposomes proved to be better in improving the extraction wound healing process than the free curcumin, giving this formulation a potential in the pharmaceutical industry.

Knee Pads Do Not Affect Physical Performance in Young Female Volleyball Players.

Knee pads have become increasingly popular among volleyball players. Given the fact high-intensity activities that are crucial to successfully playing this sport lead to an increased risk of a knee injury, the primary use of knee pads is to prevent potential injury. However, no research has been carried out to explain the effects of knee pads on the most important physical abilities in volleyball players, thus directly affecting performance. This study was undertaken to determine the effects of knee pads on the explosive power of the lower extremities, linear speed, and agility in young female volleyball players. In two separated sessions, 84 female volleyball players (age: 14.83 ± 0.72 years; height: 163.19 ± 8.38 cm; body mass: 53.64 ± 10.42 kg; VE: 5.30 ± 3.39 years) completed squat jumps (SJ), countermovement jumps (CMJ) with and without arm swing, linear sprints at 5-m and 10-m, modified t-test, and 5-10-5 shuttle test. Data analyses included descriptive statistics, paired sample T-tests and use of effect size (ES). There was no statistical difference between the two conditions for SJ (p = 0.156; ES = 0.18), CMJ (p = 0.817; ES = 0.03), CMJ with arm swing (p = 0.194; ES = 0.14), linear sprint at 5 m (p = 0.789; ES = 0.03) and 10 m (p = 0.907; ES = -0.01), modified t-test (p = 0.284; ES = 0.13), and 5-10-5 shuttle test (p = 0.144; ES = 0.19). Wearing knee pads has neither an inhibitory nor positive effects on explosive power of the lower extremities, linear speed, and agility in young female volleyball players.

Thymol regulates the functions of immune cells in the rat peritoneal cavity after l-arginine-induced pancreatitis.

AIMS: The present study aimed to evaluate the protective action of thymol towards l-arginine-induced acute pancreatitis (AP) by studying the function of rat peritoneal immune cells. MAIN METHODS: Rat peritoneal exudate cells (PECs), obtained 24 h after the injection of l-arginine (350 mg/100 g of b.w.), were evaluated for mitochondrial activity (MTT assay), adherence capacity (methylene-blue assay), and phagocyte enzyme activity (myeloperoxidase, MPO, assay). The activity of α-amylase and free MPO, as well as the concentration of reactive oxygen species (ROS, i.e. O2-), were determined in the peritoneal exudate fluid. Also, serum α-amylase activity determination and pancreatic tissue pathohistological analysis were performed. KEY FINDING: The administered thymol (50 and 100 mg/kg, per os) caused a significant decrease in the PEC mitochondrial activity and adherence capacity when compared with these functions of PECs isolated from rats with AP. A decrease in cellular MPO activity, as well as in the levels of ROS, α-amylase, and free MPO in peritoneal exudates was found in animals treated with thymol compared to the control animals with AP. Additionally, thymol administration prevented an increase in serum α-amylase activity, accompanied by the decrease in pancreatic tissue damage that follows l-arginine application. SIGNIFICANCE: The present results showed that thymol exerts significant immunomodulatory properties and a potential to silence PEC functions in inflammatory conditions such as the AP induced by l-arginine.

Effects of oleuropein on rat's atria and thoracic aorta: a study of antihypertensive mechanisms.

Oleuropein (OLE) is the main bioactive ingredient in the leaves of the olive plant Olea europaea L. (Oleaceae), which has proven beneficial due to the antiinflammatory, antiatherogenic, anticancer, antimicrobial, and antiviral effects. This study aimed to investigate the antihypertensive and vasodilator potential of OLE by analyzing its acute effects on spontaneous atrial contractions and vasomotor responses of the isolated thoracic aorta in rats. We showed that the application of OLE induces negative chronotropic and inotropic effects on the heart. OLE also causes mild aortic vasodilation given that the maximal reduction in tension of intact aortic rings precontracted with phenylephrine was approximately 30%. This vasodilation is likely dependent on the nitric oxide released from the endothelium based on the effect obtained on denuded and phenylephrine precontracted aortic rings and responses reordered following vasoconstriction induced by high concentrations of K+ and heparin. Our findings provide a basis for further testing of OLE cardiovascular effects, which may lead to subsequent clinical research for its application in the treatment of hypertension and heart disease.

An Impact of Psychological Stress on the Interplay between Salivary Oxidative Stress and the Classic Psychological Stress-Related Parameters.

Both oxidative and psychological (mental) stress are the likely culprits for several acute and chronic health disturbances, and adequate tests mimicking that are needed. Herein, in controlled laboratory surroundings, a PEBL (Psychology Experiment Building Language) test battery was used to evoke stress-related biological responses followed by tracking changes in saliva parameters. The study objectives were to determine the impact of psychological stress on selected salivatory parameters and to assess the correlation between the determined oxidative and stress parameters. The study was conducted on 36 healthy young subjects, mainly females (n = 24). Before and following the completion of a battery of four PEBL tests, subjects' saliva samples were collected. Stress-evoking changes in total antioxidant capacity and nitrite/nitrate levels, as oxidative stress parameters, and cortisol and immunoglobulin A (IgA), as parameters of psychological stress, were established and mutually correlated by comparing the values of the evaluated parameters pre- and post-PEBL test. The results showed that there is no change in the total salivary antioxidant capacity (p > 0.05); however, there was a significant increase in nitrites/nitrates levels after the PEBL test (p = 0.007). On the other hand, the determined cortisol levels after the test battery were found to be statistically significantly increased (p = 0.025) when compared to the values obtained before the test, while the levels of IgA were found to be statistically significantly decreased (p < 0.001). The only statistically significant correlation between the changes in the studied parameters was found to be the one between cortisol and IgA levels (Spearman's Rö = -0.4). These results suggest that the short-term stress induced by the PEBL test does evoke changes in the salivary mental stress-related parameters (an increase in cortisol and nitrite/nitrate levels, and a decrease in IgA), but not in the total antioxidant capacity. They also indicate that the constructed PEBL four-test battery might represent an adequate laboratory stress-inducing paradigm.

Impact of ellagic acid application on doxorubicin-induced cardiovascular toxicity model.

Doxorubicin is an anticancer agent that is commonly used to treat a number of tumors and is associated with acute and chronic changes of the cardiovascular system. Ellagic acid has strong free radical scavenging capacity, neuroprotective and hepatoprotective effects, and is known to protect against changes occurring due to diabetes, cardiovascular diseases, and cancer. Twenty-four Wistar rats were divided in four groups: control group received saline, doxorubicin group received doxorubicin in a single dose of 20 mg/kg, ellagic acid group received ellagic acid in a dose of 4 mg/kg, and doxorubicin + ellagic acid group received doxorubicin and ellagic acid in same doses as in previous groups. The effect of ellagic acid treatment, alone or in combination with doxorubicin, was studied on isolated heart frequency and strength of the contraction, and on thoracic aorta contractile responses. Application of ellagic acid to rats pre-treated with doxorubicin significantly prevented functional changes occurring in the heart, but not in the thoracic aorta tissue. Ellagic acid statistically significantly (p < 0.001) prevented doxorubicin-induced increase in heart rate, while at the same time increased single contraction force (p < 0.001) and attenuated morphological changes on heart tissue induced by doxorubicin. We can conclude that ellagic acid has potential to prevent doxorubicin-induced changes of the cardiovascular system.

Aggressiveness in Judokas and Team Athletes: Predictive Value of Personality Traits, Emotional Intelligence and Self-Efficacy.

Combat sports and martial arts are often associated with aggressiveness among the general public, although data on judo and/or martial arts and aggressiveness seem to be unclear. This research aims to compare athletes who have trained judo for a prolonged time (minimum 5 years) and athletes from various team sports, primarily regarding the manifestation of aggression, but also regarding personality traits, emotional intelligence, and self-efficacy. Also, the potential predictive value of personality traits, emotional intelligence, and self-efficacy for aggression within subsamples of judokas and team athletes was tested. The research findings showed that professional judo athletes are characterized by a low degree of aggression, especially low indirect and physical manifestations of aggression. In addition, the personality traits Honesty-Humility and Openness to experience are well expressed, contrary to Emotionality and Extraversion, which are less pronounced. They are also characterized by moderate general self-efficacy. On the other hand, members of team sports produced the opposite results, as they are characterized by increased aggression, pronounced traits of Emotionality and Extraversion, somewhat less pronounced traits of Honesty-Humility, Openness to new experience, and less pronounced general self-efficacy. The percentage of explained variability of aggression is slightly higher in the subsample of team sports and constitutes 49.9% of the variability, while in the subsample of judokas it constitutes 47.8% of the variability of the criteria. Practical implications, limitations, and future research directions were discussed.

Recreational Basketball Small-Sided Games Elicit High-Intensity Exercise With Low Perceptual Demand.

ABSTRACT: Stojanovic, E, Stojiljkovic, N, Stankovic, R, Scanlan, AT, Dalbo, VJ, and Milanovic, Z. Recreational basketball small-sided games elicit high-intensity exercise with low perceptual demand. J Strength Cond Res 35(11): 3151-3157, 2021-The purpose of this study was to describe and compare the internal and external load imposed on players during 1-a-side, 2-a-side, and 3-a-side recreational basketball small-sided games (SSGs). Twelve recreationally active, male college students were monitored across 10 minutes of 1-a-side, 2-a-side, and 3-a-side basketball SSG. Internal load variables included continuous measurement of heart rate (HR) responses, as well as rating of perceived exertion (RPE) and blood lactate concentration (BLa), after each game. External load variables included measurement of the total distance covered as well as the frequency of accelerations and decelerations. Blood lactate concentration and RPE were moderately (p < 0.05) greater in 1-a-side SSG than 3-a-side SSG. Total accelerations and decelerations were higher in 1-a-side and 2-a-side SSG compared with 3-a-side SSG (p < 0.05, moderate-large). All SSG formats resulted in players spending more time (p < 0.05, moderate-large) at higher HR intensities (81-100% HRmax) than lower intensities (≤80% HRmax). Furthermore, players covered greater distances (p < 0.05, large-very large) at lower intensities (0-12 km·h-1) and completed more accelerations and decelerations (p < 0.05, large-very large) at lower intensities (<2 m·s-2) than at higher intensities across SSG formats. Basketball SSG consisting of 1-3 players elicits an intermittent activity profile, promoting the extensive utilization of anaerobic and aerobic metabolism pathways, which potentially can lead to marked improvements in cardiovascular and musculoskeletal fitness in the general population when administered in recreational settings. Moreover, recreational basketball SSG with only 1 player per team elicits higher BLa, RPE, distances covered at low speeds as well as acceleration and deceleration volumes than SSG with 3 players per team.

Problematic Smartphone Use, Screen Time and Chronotype Correlations in University Students.

BACKGROUND: Besides numerous advantages and commodities offered by smartphones, there are obvious unhealthy effects. The global trend of an increase in the frequency of usage of smartphones, that is, prolonged screen time, is closely related to problematic smartphone use. The aim of our study was to measure the level of problematic smartphone use in a student population through the assessment of the smartphone screen time and the determination of the student chronotype, as well as through the correlation between these variables. METHODS: The participants were students of medicine of both sexes. Problematic smartphone use was measured by the short version of the Smartphone Addiction Scale. Smartphone screen time was assessed by the free Android application Quality Time. Chronotype was established by the Morningness-Eveningness Questionnaire. RESULTS: Almost one quarter (22.7%) of students involved in our study could be classified as being "smartphone-addicted". The students with problematic smartphone use more frequently (statistical significance) belonged to the evening chronotype. Those students spent significantly more time on their phones compared to the non-addicted ones. There was no statistically significant difference between the number of male and female students with problematic smartphone use. The best predictors of problematic smartphone use were longer daily smartphone screen time and evening chronotype personality. CONCLUSIONS: The results of our study showed that a significant number of students of medicine showed problematic smartphone use. There was a strong correlation between extensive screen time and the level of problematic smartphone use in the studied population.

Game format alters the physiological and activity demands encountered during small-sided football games in recreational players.

BACKGROUND: Conditioning in the form of football small-sided games (SSG) is being increasingly utilized as a health-promoting and performance-enhancing activity. OBJECTIVE: The aim of this study was to quantify and compare the physiological responses and activity demands encountered during 3-a-side, 4-a-side, and 5-a-side football SSG in recreational players. METHOD: Heart rate, blood lactate (BLa), rating of perceived exertion (RPE) and activity demands were measured across 2 × 20-min football sessions played on a 40 × 20-m pitch in 12 recreationally active college students. Data were collected over a period of two weeks using a repeated-measures crossover design. RESULTS: Mean heart rate was higher (moderate) during 5-a-side than 4-a-side (p = 0.02) and 3-a-side SSG (p < 0.001). BLa tended to be higher (small) in 3-a-side compared to 4-a-side (p = 0.12) and 5-a-side SSG (p = 0.46). The total distance covered was lower (large) during 5-a-side than 4-a-side SSG (p = 0.02), while the total number of accelerations (p = 0.01) and decelerations (p = 0.02) were higher (large) during 5-a-side than 4-a-side SSG. CONCLUSION: These data suggest: 1) 5-a-side SSG require a greater intermittent workload and exacerbated HR responses; 2) 4-a-side SSG require more sustained activity (distance); and 3) 3-a-side SSG result in higher BLa compared to other SSG formats. The observed intermittent workload and exacerbated HR response in 5-a-side SSG were likely due to greater turnover rates with more frequent interceptions. Sustained activity in 4-a-side SSG might be underpinned by format-specific structures permitting optimal team work, while isolated guarding of players in 3-a-side SSG may have exacerbated BLa responses.