Leg Muscles Research Articles

Endurance of leg muscle strength and endurance of arm muscle strength to the ability of swimming speed 200 meters breaststroke

The lack of breaststroke swimming ability among athletes has led to a decline in breaststroke swimming performance in the Solok city swimming association. This problem is thought to be related to the low endurance of leg and arm muscles to the swimming speed of 200 meters breaststroke. This correlational study aims to reveal the contribution of leg muscle endurance, arm muscles, and the joint contribution of both to swimming speed 200 meters breaststroke in athletes coaching achievements in the Solok city swimming association. This study involved 25 swimming athletes in Solok city, with total sampling technique. Data on leg muscle strength endurance was measured through the squat jump test, arm muscle strength endurance through the push up test, and swimming speed through the 200 meter breaststroke swimming test. Data were analyzed using simple and multiple correlations with a significant level of α = 0.05, and the contribution was calculated by the formula r² x 100%. The results of data analysis showed that leg muscle strength endurance contributed 74.65%, while arm muscle strength endurance contributed 70.06%. The combination of both contributed 74.99% to the ability of 200 meters breaststroke swimming speed of athletes coaching achievements in swimming associations in Solok city.

Abstract 4137264: Subclassification of Peripheral Artery Disease Based on Muscle Force: Leg Failure with Reduced Muscle Force and Leg Failure with Preserved Muscle Force

Introduction: All claudicating patients with peripheral artery disease (PAD) exhibit leg failure, as evidenced by distinct walking impairment. However, based on a detailed evaluation of leg biomechanics, some claudicating patients maintain preserved leg muscle strength, while others demonstrate reduced strength. In this study, we aim to compare the clinical and physiological characteristics of the two groups. Methods: Fifty-four claudicating patients were categorized into two groups: leg failure with preserved muscle force (LEF-PF) versus leg failure with reduced muscle force (LEF-RF), based on the peak torque (PT) from performing maximum isometric plantar flexion contractions on a Biodex system. All patients underwent history and physical exam, measurement of leg hemodynamics, walking performance and quality of life, and gastrocnemius biopsy to evaluate the histology and biochemistry of the affected leg muscles. We used independent samples T test and chi-square test to compare the two groups. Results: LEF-PF (N=19, PT 92±15 Nm) and LEF-RF (N=35, PT 49±13 Nm) had similar demographic and comorbidity profiles. While ankle-brachial index didn't differ between the two groups, during the reactive hyperemia test, ankle pressure of LEF-RF dropped more significantly (p=0.021) upon occlusion release and took longer to recover (p=0.023). Both groups performed similarly on the Gardner Treadmill test, but LEF-PF performed better in the 6-Minute Walking test (p=0.062). LEF-PF also trended towards higher scores on the modified falls efficacy scale (p=0.056). Histologically, gastrocnemius muscle from LEF-PF had larger myofibers, while biochemically, they exhibited lower mitochondrial respiratory activity dependent on complex-II compared to LEF-RF. Conclusion: Our study presents a novel approach to understanding the physiology of claudication, focusing on the strength of the ischemic muscles. Despite comparable demographics and hemodynamics at rest, notable differences separate the two groups during stress-induced hemodynamics, walking performance, myofiber histology, and mitochondrial biochemistry. Further investigations are necessary to elucidate the underlying mechanisms behind the differences in muscle strength among patients with claudication. Such insights may enhance our understanding of PAD physiology and potentially correlate with variations in mortality rates, progression to more advanced PAD stages, and responses to different therapeutic interventions.

The Relatioship between Leg Muscle Strength Arm Muscles and Self-Confidence with 50 Metres Swimming Speed Free Style

The purpose of this study was to determine the relationship between leg muscle strength and self-confidence, arm muscle strength and self-confidence, and leg muscle strength, arm muscle strength and self-confidence with 50-meter freestyle swimming speed. The sample of this study was 30 male students. In accordance with the formulation of the problem and the objectives to be achieved, the research method used in this study is a quantitative method with correlation and descriptive techniques, namely the researcher will see the relationship between one variable and another. Based on the results of the analysis of research data and discussion, it can be concluded that the following research results (a) there is a relationship between leg muscle strength and 50-meter freestyle swimming speed of 3.61 (b) there is a relationship between arm muscle strength and 50-meter freestyle swimming speed of 3.47. (c) there is a relationship between self-confidence and 50-meter freestyle swimming speed of 4.95 which then the relationship between leg muscle strength and arm muscle strength and self-confidence with 50-meter freestyle swimming speed of 14.99. Thus, the stronger the leg and arm muscles, as well as good self-confidence, the better the 50-meter freestyle swimming speed of male students of the Health and Sports Study Program, FKIP Unpatti Ambon. Keywords: Swimming 50 meters freestyle, leg muscle strength, arm muscle, self-confidence

The influence of leg muscle power, waist flexibility and self-confidence on soccer long passing ability

The problem in this study is the low ability of Long Passing soccer school players Buah Hati. This study aims to see the effect of leg muscle strength, waist flexibility and self-confidence on long passing ability, both directly and indirectly and simultaneously. This type of research is quantitative with a path analysis approach. the sample in this study were all 30 players of Buah Hati Football School. Sample withdrawal using saturated sampling technique. The leg muscle power instrument uses the Vetical Jump Test, waist flexibility using the Sit and reach test, confidence using a Likert scale model questionnaire and long passing ability with the Aerial Pass for Accuaracy test. The results showed that, (1) there is a direct effect of leg muscle power on long passing ability with ρz1 = 0.337 or 11.35%, (2) there is a direct effect of waist flexibility on long passing ability, with ρz2 = 0.458 or 20.97%, (3) there is a direct effect of self-confidence on long passing ability, with ρz3 = 0.225 or 5.06%, (4) there is an indirect effect of leg muscle power on Long Passing ability through self-confidence, with ρz31 = 0.1131 or 11.31%, (5) there is an indirect effect of waist flexibility on Long Passing ability through self-confidence, with ρz32 = 0.0893 or 8.93% and (6) there is an effect of leg muscle power, waist flexibility and self-confidence simultaneously on three point shooting ability, with ρz123 = 0.942 or 94.2%.

Repeatability of diffusion kurtosis tensor parameters in muscles of the lower legs.

The aim of this study was to provide measurements from and investigate the repeatability of diffusion kurtosis tensor parameters in the muscles of the lower legs. Test-retest acquisition of a kurtosis tensor sequence was performed in 13 healthy volunteers. Quantitative kurtosis tensor parameters were derived, and repeatability of each parameter was evaluated by muscle group and over the whole muscle through intraclass correlation coefficient (ICC) and within-subject coefficient of variation (wsCV). Bland-Altman analysis was also conducted. Differences in parameter values by muscle group were investigated through an analysis of variance. Axial kurtosis and radial kurtosis values from the test data were 0.63 ± 0.04 and 0.70 ± 0.05, respectively. Kurtosis tensor parameters from all muscle groups and over the whole muscle had wsCV below 15%. ICC for the parameters from most muscle groups was above 85%, with the lowest ICC over the whole muscle being 88.39%. The medial gastrocnemius and extensor digitorum longus showed highest repeatability. Mean, axial, and radial diffusivity had higher wsCV despite being lower-order terms than kurtosis. This study sought to examine the repeatability of diffusion kurtosis tensor-derived parameters in the legs and verify that they could potentially be used as longitudinal imaging metrics. wsCV values from test-retest data indicated high repeatability throughout all examined muscle groups. There were minimal differences in kurtosis and diffusivity parameters between muscle groups in this healthy volunteer cohort.

Genome-wide methylation and transcriptome differential analysis of skeletal muscle in broilers with valgus-varus deformity

ABSTRACT 1. Valgus-varus deformity (VVD) is a disease that severely affects leg function in broilers and for which there is no effective control method current available. Although DNA methylation has an important impact on most physiological and pathological processes, its involvement in skeletal muscle growth and development in VVD broilers is unknown. In this study, genome-wide DNA methylation was analysed in VVD-affected and normal broilers using whole genome resulphite sequencing. 2. The results showed that in the cytosine-phosphoric acid-guanine (CG) sequence environment there was a methylation rate of about 55% and 4,265 differentially methylated regions (DMRs) were found in the CG. Of these, 550 were located in the promoter, 547 in the exon region, and 1,718 in the intron region. 3. All differentially methylated genes (DMGs) were analysed for enrichment of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The GO was enriched in pathways related to protein degradation such as proteasome complex, endopeptidase complex and extracellular region. The KEGG pathways were enriched in signalling pathways related to protein degradation and catabolism such as proteasome, nitrogen metabolism, adherens junction and alanine. 4. Protein interactions analysis revealed that FOS, MYL9, and FRAS1 had a high degree of interactions, in which the DNA methylation level of the MYL9 promoter region was negatively correlated with mRNA expression level. Further studies showed that 5-azacytidine (5-AzaC) inhibited DNMT1 and DNMT3A gene expression and promoted MYL9 expression. 5. This study systematically investigated overall DNA methylation patterns in the leg muscle of VVD and normal broilers. It screened common differential genes in conjunction with transcriptomic data to further identify genes associated with muscle growth and development. This study provides new insights to better understand the pathogenesis of VVD from an epigenetic perspective.

The Reliability and Validity of the Rebound Countermovement Jump in National Collegiate Athletic Association Division I American Football Players.

Talpey, SW, Drake, M, Haintz, L, Belanger, A, O'Grady, MW, Young, WB, Mundy, PD, James L, Gabbett, TJ, Gardner, EC. The reliability and validity of the rebound countermovement jump in National Collegiate Athletic Association Division I American Football Players. J Strength Cond Res XX(X): 000-000, 2024-The purpose of this study was to investigate the reliability and validity of the rebound countermovement jump (R-CMJ), as an alternate test of leg muscle function to the CMJ and drop jumps (DJs). Because the first phase of the R-CMJ mimics that of the CMJ, it is hypothesized that variables obtained in phase I of the R-CMJ will be like those of a CMJ. Similarly, because the second phase of a R-CMJ mimics a DJ, it is believed that the variables obtained from phase II will be like those from a DJ. Collegiate male American football players (N = 46) aged 18-24 years completed CMJs and R-CMJs on a portable force plate. Tests were completed on 3 separate days to determine the repeatability of select variables and to establish their validity. In addition, a subgroup (N = 20) of players from the cohort completed DJs from both 30 cm (DJ30) and 45 cm (DJ45) to determine the concurrent validity of the variables obtained from the second phase of the R-CMJ. Most variables obtained from the CMJ and R-CMJ phase I were found to be reliable, except for time-to-take-off. The variables from the DJ30, DJ45, and R-CMJ phase II displayed moderate to good reliability; however, all coefficient of variations were >10%. Jump height achieved in the CMJ was significantly greater than that achieved in phase I of the R-CMJ. The reactive strength index was significantly different in the R-CMJ compared with the DJ from both 30 and 45 cm heights. Although the R-CMJ may be inviting for coaches to use owing to its ease and time efficiency, the results of this study highlight that it may not provide a valid representation of an athlete's reactive strength.

Age- and Gender-Specific Reference Values for Physical Performance in Tunisian Youth Basketball Players

Background/Objectives: Physical performance is becoming increasingly critical in basketball, as it directly influences players’ agility, power, and endurance. This study aimed to assess the progression of body composition and physical performance metrics across different ages and genders, establishing age- and gender-specific reference values for Tunisian basketball athletes. Methods: A total of 469 Tunisian basketball players (239 boys and 230 girls) were assessed and grouped by age. Anthropometric measures—including standing and sitting height, body mass, leg length, body mass index, fat mass, fat-free mass, body fat percentage, wingspan, and leg muscle volume—were collected alongside physical performance metrics. Performance tests included countermovement and squat jumps, change-of-direction speed, maximal oxygen uptake, flexibility, the five-jump test, and 5 m, 10 m, and 20 m sprints with and without the ball. Normative data were generated based on age and gender categories. Results: The findings revealed significant age-related improvements in both anthropometric and performance parameters. Boys consistently outperformed girls in physical and fitness-related measures, with gender differences becoming more pronounced with age. Stepwise regression analyses indicated that, for boys, body fat percentage, leg muscle volume, standing height, and wingspan were the best predictors of physical performance. For girls, body fat percentage, standing height, and sitting height were identified as key predictors. Conclusions: The newly established Tunisian reference values for physical performance in youth basketball provide valuable benchmarks that can support the development of explosive power and strength in players, aiding in talent identification and potentially enhancing individual and team performance outcomes.

Comparative Analysis of Lower Limb Muscle Strength Based on Gender and Children Aged 10-12 Year at Muhammadiyah Elementary School 08 Dau

Background: The growth and development of children aged 0-12 years are individuals who experience a very rapid growth and development process. However, in this modern era, technological developments have resulted in children becoming very lazy and reluctant to do physical activity. This can affect the development of motor skills. Muscle strength is a crucial aspect in human physical development. Muscle strength, especially in the lower leg muscles, can be influenced by several factors such as age and gender. Objective: to determine the comparison of leg muscle strength based on gender and children aged 10-12 years at SD Muhammadiyah Malang. Method: The research used was cross-sectional by taking a sample of 116 respondents. Meanwhile, the test used uses a comparison test. Results: One way ANOVA test showed p-value = 0.79 (<0.05) which shows that there is no significant difference at the age level of 10, 11 and 12 years on leg muscle strength in children. And Mann Whitney p-value = 0.00 (<0.05) which shows that there are differences based on male and female gender. Conclusion: Comparative analysis of lower leg muscle strength based on gender and age 10-12 years at SD Muhammadiyah 08 Dau did not provide significant results regarding differences in lower leg muscle strength based on age 10, 11, 12 years. Meanwhile, there are differences in lower leg muscle strength based on gender.

Muscle characteristics of lower limb in association with physical activity in candidates of total knee arthroplasty with knee osteoarthritis

Background&AimsThis study aimed to clarify the association between physical activity (PA) and physical functions, including both muscle quantity and quality of ankle plantar flexor muscles in patients with knee osteoarthritis (OA). MethodsA retrospective cohort study was conducted with ninety-two patients with knee OA. PA, leg muscle cross-sectional area (CSA), knee strength, passive knee angle, and knee pain of the affected side were assessed. PA was assessed by the 2011 Knee Society scoring system. CSA of the quadriceps and ankle plantar flexor muscles on the affected side was measured using a computed tomography image. Based on muscle attenuation assessed with Hounsfield units (HU), the muscle quality of targeted muscle was divided into 4 groups as follows: fat tissue (-190 to -30 HU), very low-density muscle (-29 to -1 HU), low-density muscle (0 to 34 HU), and normal-density muscle (NDM, 35 to 100 HU). The CSA was obtained for each of the 4 groups. Univariate and multivariate linear regression analyses were performed to determine the factors associated with PA. ResultsThe regression analysis revealed that higher PA was independently associated with the NDM CSA of ankle plantar flexor (β = 0.51), higher knee extension strength (β = 0.28), and milder knee pain (β = -0.29) after adjustment with age, sex, height, weight, and body mass index. ConclusionThe present study suggested that NDM CSA of ankle plantar flexor in addition to knee function is one of the factors determining the PA in patients with knee OA.

Increase the speed of running 100 meters using the bench and skipping training methods

Background and Study Aim. Running 100 meters requires optimal speed, strength, and physical endurance. Running speed is often a key indicator of physical ability and athletic performance. However, not everyone achieves optimal speed and physical ability in running the 100 meters. Many factors influence a student's running performance, including the training methods used. The aim of the research is to determine the increase in speed for running 100 meters using bench and skipping training methods. Material and Methods. This research is an experimental study aiming to find cause and effect relationships in one or more experimental groups through different training treatments. The design used is a two-group pretest-posttest design. The participants were male students actively involved in sports activities, capable of performing running techniques well, and willing to participate in the training sessions. Initially, students underwent a pretest to determine their treatment group by ranking the pretest scores. This allowed the formation of two groups: one group of 15 students participating in bench climbing exercises, and another group of 15 students engaging in skipping exercises, using ordinal pairing. The instrument used for the 100-meter running test is the 100-meter running test. Results. Based on the results of hypothesis testing using pretest and posttest t-tests, the 100-meter running speed after bench up and down training was 4.621. The pretest and posttest data for 100-meter running speed with skipping training was 4.790. For the posttest, the running speed for 100 meters with bench up and down training and skipping training was 4.240. The two-way p-value was 0.000, which is less than 0.05, indicating a significant difference in the 100-meter running speed before and after the exercise. Conclusions. Bench climbing exercises can increase the strength of the primary leg muscles used in sprinting, such as the quadriceps, hamstrings, and calves. These exercises improve body balance and coordination, which are crucial for efficient running posture and technique. Meanwhile, skipping can enhance explosive power and the ability of leg muscles to generate power quickly and efficiently. Skipping also improves coordination between hands and feet, aiding in maintaining rhythm and efficiency in running movements. Overall, bench climbing exercises are more effective in improving 100-meter running performance compared to skipping exercises.

Effects of genotype and sex on carcass composition, meat quality, digestive tract morphometries and leg bone dimensions of spent parent Pekin ducks

The purpose of the present study was to analyze carcass composition, physicochemical properties, muscle texture, and structure, as well as morphometry of the digestive tract and leg bone dimensions of Cherry Valley ducks (SM3 Heavy hybrid) and Orvia ducks (ST5 Heavy hybrid) after laying. A total of 32 ducks were dissected, 8 females and 8 males from each breeding set. Analysis of meat quality (breast muscle, leg muscle) in terms of color (L*, a*, b*), acidity (pH24), electrical conductivity (EC24), and basic chemical composition (protein, water, fat, collagen) was performed. Analysis of the texture and structure of the pectoral muscle was also performed. The dimensions of the various lengths of the digestive tract and the dimensions of the tibia and femur were analyzed. Cherry Valley ducks after laying have better slaughter performance and a higher proportion of breast muscle in the carcass (P < 0.001). Also more favorable chemical composition (protein, fat, water) and physical properties (acidity, electrical conductivity, thermal loss) of muscle. In terms of texture characteristics, the pectoral muscle of Cherry Valley ducks was more elastic and cohesive, but also more flexible with higher viscosity, while the pectoral muscles of Orvia ducks in terms of structure were characterized by smaller values of the analyzed characteristics (cross-sectional area of fibers and smaller vertical and horizontal diameter). Analyzing the morphometry of the digestive system, Orvia ducks were characterized by longer sections of the digestive tract, which certainly has a beneficial effect on the absorption of nutrients. In terms of tibia and femur measurements taken, there were no differences between genotypes, while males were characterized by higher values of the analyzed traits compared to females.

Comparative effects of cognitive and instability resistance training versus instability resistance training on balance and cognition in elderly women

This study investigates the effects of integrated instability resistance training and cognitive training (IRCT) versus isolated instability resistance training (IRT) on balance, gait, muscle strength, and cognitive functions in elderly women.This randomized controlled trial included 36 participants, with 18 in the IRCT group and 18 in the IRT group. The sample size was estimated to achieve a statistical power of 0.95 with a large effect size (0.40; n = 12 each group). The closed-eye single-leg stand test was measured for static balance, the closed-eye stepping test, and the Timed Up and Go Test (TUGT) were measured for dynamic balance. Dual-task balance was assessed by combining the TUGT with cognitive tasks (TUGT-C) and motor tasks (TUGT-M). Gait performance was evaluated using a gait function system. Lower limb muscle strength was measured with the 30-Second Chair Stand Test. Cognitive function was assessed through the Trail Making Test (TMT), Digit Span Test (DST), Stroop Color and Word Test (Stroop), and Digit Symbol Substitution Test (DSST). Results IRCT group showed better improvements in both cognitive (p < 0.001) and motor (p = 0.812 for baseline; p < 0.001 for post-intervention) dual-task abilities, IRCT also experienced better enhancement in certain cognitive functions, particularly in the TMT (p = 0.001) and DSST (p = 0.022) compared to the IRT group. Both groups demonstrated enhancements in walking abilities as shown on selective markers of the gait performance test (p < 0.05) and leg muscle strength via 30-Second Chair (p < 0.001 for time main effect). These results suggest that combining cognitive exercises with physical training more effectively addresses the complex challenges associated with aging in women. The study highlights the potential of comprehensive training approaches in boosting health and quality of life for the elderly, with implications for developing tailored exercise programs focused on reducing fall risks and enhancing quality of life in this population.

Influence of genotype on carcass composition, metric traits of the digestive system and leg bones of laying hens after the egg-production season

Context The genotype of laying hens is one of the most important factors influencing their carcass composition and anatomical features. Aims The aim of the present study was to compare two genotypes of laying hens, Lohmann Brown and Lohmann White, after the laying period. Methods The experimental material consisted of 26 carcasses obtained after slaughtering spent laying hens at the age of 83 weeks. Key results The genotype of the birds had a significant (P &lt; 0.05) effect on carcass weight, and the proportion (%) of the breast muscle, leg muscle and gizzard weight. Significant correlations were also found between bodyweight and the weight of the stomach, proventriculus, liver and spleen. The origin of the laying hens also had a significant impact on the length of the sections on intestinal segments, namely, jejunum, ileum and colon. Significant differences in the correlations between bodyweight and length of duodenum, jejunum and rectum were also found. The compared hybrids of laying hens differed significantly in the dimensions of the femur and tibia. Lohmann Brown (LB) hens were characterized by higher greatest length, medial length, smallest breadth of the corpus, and greatest breadth of the distal end of the femur compared with Lohmann White (LW) hens. Dimensions of the tibia greatest length, axial length, smallest breadth of the corpus, greatest breadth of the distal end and greatest depth of the distal end in LB hens were also significantly (P &lt; 0.05) higher than those in LW hens. Conclusions The results showed that the genotype of laying hens tested after the laying period influenced carcass weight and muscle percentage, as well as differentiated the birds in terms of dimensions of individual segments of the digestive tract, femur, and tibia bones. Implications The results of this research may be useful for consumers of laying hen carcasses and people interested in poultry anatomy.

The effect of variability knee tuck jump training and box jump training on the explosive capabilities of legs muscles

The problem in this research is the low jumping ability of male volleyball athletes which effect on the decreased performance. The aim of this research is to know the effect of knee tuck training and box jump training on the explosive capability of the legs muscles of volleyball athletes. The type of the research is quasi-experiment with the research population is all male volleyball athletes at SMK 1 Solok Selatan which totally 24 athletes aged 17 years. The technique of sampling which is used is total sampling with a sample is 24 athlete. The instrument in this research is to use Vertical Jump to measure the explosive power of leg muscles. Before giving a treatment, an initial test (pte-test) is carried out to see the explosive power of leg muscles. The testees used as a samples are drawn into two groups. The group 1 is given the Knee Tuck Jump training treatment and the group 2 is given Box Jump Training treatment. This treatment is given 16 times (8 weeks), then the final test will be given. The data analysis technique which is used to test the hypothesis is t analysis at the significance level of 5%. Based on the data analysis in this study, 1) the Knee Tuck Jump get an average increase of (7.703) and was marked by getting t count (10.631)&gt; t table(1.796). It means that the application of Knee Tuck Jump can increase the explosive power capability of leg muscles, 2) the Box Jump training get an average increase (2.456) and was marked by getting t count (9.240)&gt; t table (1.769), it means that the application of the Box Jump training can increase the explosive power of leg muscles, 3) there was an influence training. Where in Knee Tuck Jump is getting the average increase is (7.703) while the box jump training is (2.456) and is indicated by getting t count (2.05)&gt;t table (1.796). It means that the application of Knee Tuck Jump training and Box jump training could increase the explosive power capability of the leg muscles, where the Knee Tuck Jump training shows better results in increasing the explosive power of the leg muscles. Coaches apply knee tuck jump training at the right age level to achieve maximum results according to the athlete's training capacity.

Supraspinal contributions to defective antagonistic inhibition and freezing of gait in Parkinson's disease.

The neuromuscular circuit mechanisms of freezing of gait in Parkinson's disease have received little study. Technological progress enables researchers chronically to sense local field potential activity of the basal ganglia in patients while walking. To study subthalamic activity and the circuit processes of supraspinal contributions to spinal motor integration, we recorded local field potentials, surface EMG of antagonistic leg muscles and gait kinematics in patients while walking and freezing. To evaluate the specificity of our findings, we controlled our findings to internally generated volitional stops. We found specific activation-deactivation abnormalities of oscillatory activity of the subthalamic nucleus both before and during a freeze. Furthermore, we were able to show with synchronization analyses that subthalamo-spinal circuits entrain the spinal motor neurons to a defective timing and activation pattern. The main neuromuscular correlates when turning into freezing were as follows: (i) disturbed reciprocity between antagonistic muscles; (ii) increased co-contraction of the antagonists; (iii) defective activation and time pattern of the gastrocnemius muscle; and (iv) increased subthalamo-muscular coherence with the gastrocnemius muscles before the freeze. Beyond the pathophysiological insights into the supraspinal mechanisms contributing to freezing of gait, our findings have potential to inform the conceptualization of future neurorestorative therapies.

Prevalence of Vitamin D Deficiency in Children Aged Between 1 to 16 Years: An Observational Study

Introduction: Vitamin D is crucial for bone growth, mineralization, and various metabolic processes in the body. Consequently, a deficiency or insufficiency of this vitamin can lead to long-term consequences, especially in children. Therefore, this study aimed to assess the prevalence of vitamin D deficiency vitamin D deficiency in children aged between 1 to 16 years. Methods: This was an observational study conducted in the Department of Paediatrics, Dr. Sirajul Islam Medical College &amp; Hospital, Dhaka &amp; Ad-Din Akij Medical College Hospital, Khulna, Bangladesh during the period from July 2023 to July 2024. The study enrolled children aged 1 to 16 years from the pediatric department, excluding those with specific health issues. Data analysis was conducted with SPSS 23, and ethical approval was obtained from Dr. Sirajul Islam Medical College &amp; Hospital and Ad-Din Akij Medical College Hospital. Results: In our study, we included 100 children with vitamin D deficiency symptoms who attended the paediatrics department of our study institutions. Participants were categorized into four age groups: 1-3 years (30%), 4-6 years (15%), 7-10 years (21%), and 11-16 years (34%). The sample comprised 59% females and 41% males, with an average age of 12.84 years. Most were from middle-class families (39%), and 48% were in primary school. Common health issues included leg pain (58%), growth retardation (47%) and muscle pain/bone pain (39%). Vitamin D deficiency was prevalent, with rates of 50.00% in 1-3 years, 53.33% in 4-6 years, 47.62% in 7-10 years, and 61.76% in 11-16 years, indicating increased insufficiency with age. Conclusion: This study shows that vitamin D deficiency is high among our study children. A comprehensive action plan, including supplementation and food fortification, is crucial to prevent this deficiency in Bangladesh.

Evaluation of the Growth Performance and Meat Quality of Different F1 Crosses of Tengchong Snow and Xichou Black Bone Chicken Breeds.

Unlike other chicken breeds, Xichuan Black Bone (XBB) chickens are an established breed in China with excellent production performance and unique characteristics, including black meat, beaks, skin, bones, and legs, and they produce blue-shelled eggs. The Tengchong Snow (TS) chicken breed has relatively lower growth performance than commercial breeds but is considered one of the main genetic treasures of black meat in China. To improve the production and meat quality traits of the TS chickens by hybridization, the current study aimed to investigate the growth performance, carcass indices, meat quality physical properties, and muscle fiber traits of fiber traits of F1 crosses of TS with XBB chickens. Three groups of crossbreeding combinations were produced: (1) XT group (XBB × TS ), (2) TX group (TS × XBB ), and (3) TT group (TS × TS ), with the TT group used as a control. A total of 725 healthy chicks (XT group: 247, TX group: 180, TT group: 298) were reared up to 20 weeks of age to estimate the growth performance and associated meat parameters. The results showed that the XT and TX groups had higher body weight and body size compared with the TT group (p < 0.05). Similarly, breast width, breast length, width of body, and carcass weights were also greater (p < 0.05) in the XT and TX groups compared with the TT group. Meat physical properties, including color, water-holding capacity, and tenderness, were improved (p < 0.05) for the XT and TX group compared to the TT group. The XT group had the better color of the leg muscles with the unique orientation of muscle fibers. Based on the results, the XT group is more in line with the future breeding direction as they have greater body weight, larger size, and lower abdominal fat. This study is a baseline technical reference for the protection, evaluation, and utilization of germplasm resources of Tengchong Snow chicken for screening the best matching lines and combinations with local chickens.

Transcriptomic analysis reveals differentially expressed genes associated with meat quality in Chinese Dagu chicken and AA+ broiler roosters

BackgroundWith the improvement of living standards, the quality of chicken has become a significant concern. Chinese Dagu Chicken (dual-purpose type) and Arbor Acres plus broiler (AA+ broiler) (meat-type) were selected as the research subjects in this study, the meat quality of the breast and leg muscles were measured. However, the molecular mechanism(s) underlying regulation of muscle development are not yet fully elucidated. Therefore, finding molecular markers or major genes that regulate muscle quality has become a crucial breakthrough in chicken breeding. Unraveling the molecular mechanism behind meat traits in chicken and other domestic fowl is facilitated by identifying the key genes associated with these developmental events. Here, a comparative transcriptomic analysis of chicken meat was conducted on breast muscles (BM) and leg muscles (LM) in AA+ broilers (AA) and Dagu chicken (DG) to explore the differences in their meat traits employing RNA-seq.ResultsTwelve cDNA libraries of BM and LM from AA and DG were constructed from four experimental groups, yielding 14,464 genes. Among them, Dagu chicken breast muscles (DGB) vs AA+ broilers breast muscles (AAB) showed 415 upregulated genes and 449 downregulated genes, Dagu chicken leg muscles (DGL) vs AA+ broilers leg muscles (AAL) exhibited 237 upregulated genes and 278 downregulated genes, DGL vs DGB demonstrated 391 upregulated genes and 594 downregulated genes, and AAL vs AAB displayed 122 upregulated genes and 154 downregulated genes. 13 genes, including nine upregulated genes (COX5A, COX7C, NDUFV1, UQCRFS1, UQCR11, BRT-1, FGF14, TMOD1, MYOZ2) and four downregulated genes (MYBPC3, MYO7B, MTMR7, and TNNC1), were found to be associated with the oxidative phosphorylation signaling pathway. Further analysis revealed that the differentially expressed genes (DEGs) from muscle were enriched in various pathways, such as metabolic pathways, oxidative phosphorylation, carbon metabolism, glycolysis, extracellular matrix-receptor interaction, biosynthesis of amino acids, focal adhesion, vascular smooth muscle contraction, and cardiac muscle contraction, all of which are involved in muscle development and metabolism. This study also measured the meat quality of the breast and leg muscles from the two breeds, which demonstrated superior overall meat quality in Chinese Dagu Chicken compared to the AA+ broiler.ConclusionsOur findings show that the meat quality of dual-purpose breeds (Chinese Dagu chicken) is higher than meat-type (AA+ broiler), which may be related to the DEGs regulating muscle development and metabolism. Our findings also provide transcriptomic insights for a comparative analysis of molecular mechanisms underlying muscle development between the two breeds, and have practical implications for the improvement of chicken breeding practices.

Justification of the effective sequence of group fitness classes with second mature women (45-55 years old)

This article deals with issues that are aimed at the organization of strength training. First of all, it is necessary to note significant differences between women and men in terms of strength. In women, they are 15-20% lower than in men. Women have a lower tendency to gain muscle mass. This is primarily related to the hormonal background, since the male hormone testosterone is responsible for the growth of muscle mass, and its amount in the body of women is many times smaller than that of men. At the same time, women's ability to display strength indicators of leg muscles is close to men's. Experts in age-related physiology note that at the age of 40-45, reverse processes begin in a woman's body. The main metabolism slows down, the productivity of various organs and systems decreases, the possibility of various pathological processes, chronic diseases, etc. increases. In connection with the decrease in the hormonal background, negative changes are observed in all organs and systems of the body. Blood pressure often rises, a tendency to osteoporosis appears, fat metabolism is disturbed, which often leads to an increase in body fat. There are significant changes in the respiratory system, the vital capacity of the lungs decreases, the mobility of the chest decreases. After 40 years, there is a significant decrease in muscle strength in women. The elasticity of muscles, tendons, and joint performance is lost. At the same time, muscle tone decreases, which leads to negative changes in posture.