Beyond sarcopenia: frailty in chronic haemodialysis patients.

Background: Frailty, characterized by vulnerability, reduced reserves and increased susceptibility to severe events, is a significant concern in chronic haemodialysis (HD) patients. Sarcopenia, corresponding to the progressive loss of muscle mass and strength, may contribute to frailty by reducing functional capacity, mobility and autonomy. However, consensus lacks on the optimal bedside frailty index for chronic HD patients. This study investigated the influence of frailty on chronic HD patient survival and explored the associated factors. Methods: A total of 135 patients were enrolled from January to April 2019 and then followed up prospectively until April 2022. At inclusion, frailty was assessed by the Timed Up and Go (TUG) and Short Physical Performance Battery (SPPB) tests including gait speed, standing balance and lower limb muscle strength. Results: From a total of 114 prevalent chronic HD patients (66% men, age 67.6 ± 15.1 years), 30 died during the follow-up period of 23.7 months (range 16.8-34.3). Deceased patients were older, had more comorbidities and a higher sarcopenia prevalence (P < .05). The TUG and SPPB test scores were significantly reduced in patients who had died [SPPB total score: 7.2 ± 3.3 versus 9.4 ± 2.5; TUG time 8.7 ± 5.8 versus 13.8 ± 10.5 (P < .05)]. Multivariate analysis showed that a higher SPPB score (total value >9) was associated with a lower mortality risk [hazard ratio 0.83 (95% confidence interval 0.74-0.92); P < .03). Each component of the SPPB test was also associated with mortality in univariate analysis, but only the SPPB balance test remained protective against mortality in multivariate analysis. Older age, lower handgrip strength and lower protein catabolic rate were associated with SPPB total scores <9, SPPB balance score and TUG time >10 s. Conclusions: Screening for frailty is crucial in chronic HD patients, and incorporating SPPB, especially the balance test, provides valuable insights. Diminished muscle strength and inadequate protein intake negatively influence the SPPB score and balance in chronic HD patients. Effective identification and management of frailty can therefore improve outcomes. CLINICAL TRIAL REGISTRATION ClinicalTrialsgov: NCT03845452.

Risk Factors for Bone Microarchitecture Impairments in Older Men with Type 2 Diabetes - The MrOS Study.

CONTEXT: Impaired bone microarchitecture, assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT), may contribute to bone fragility in type 2 diabetes (T2DM) but data on men are lacking. OBJECTIVE: To investigate the association between T2DM and HR-pQCT parameters in older men. METHODS: HR-pQCT scans were acquired on 1794 participants in the Osteoporotic Fractures in Men (MrOS) study. T2DM was ascertained by self-report or medication use. Linear regression models, adjusted for age, race, BMI, limb length, clinic site, and oral corticosteroid use, were used to compare HR-pQCT parameters by diabetes status. RESULTS: Among 1777 men, 290 had T2DM (mean age 84.4 years). T2DM men had smaller total cross-sectional area (Tt.AR) at the distal tibia (p=0.028) and diaphyseal tibia (p=0.025), and smaller cortical area at the distal (p= 0.009) and diaphyseal tibia (p= 0.023). Trabecular indices and cortical porosity were similar between T2DM and non-T2DM. Among men with T2DM, in a model including HbA1c, diabetes duration, and insulin use, diabetes duration ≥ 10 years, compared with <10 years, was significantly associated with higher cortical porosity but with higher trabecular thickness at the distal radius. Insulin use was significantly associated with lower cortical area and thickness at the distal radius and diaphyseal tibia and lower failure load at all three scan sites. Lower cortical area, cortical thickness, total BMD, cortical BMD, and failure load of the distal sites were associated with increased risk of incident non-vertebral fracture in T2DM. CONCLUSIONS: Older men with T2DM have smaller bone size compared to non-T2DM, which may contribute to diabetic skeletal fragility. Longer diabetes duration was associated with higher cortical porosity and insulin use with cortical bone deficits and lower failure load.

Association between grip strength and walking pace with incidence of degenerative cervical myelopathy: a UK biobank observational study.

PURPOSE: This study investigates the association between handgrip strength, walking pace, and the incidence of degenerative cervical myelopathy (DCM) using the UK Biobank dataset. METHODS: We analyzed data from 364,716 UK Biobank participants without prior neurological conditions. Handgrip strength was measured with a dynamometer, and walking pace was self-reported. Cox proportional hazards models assessed hazard ratios (HRs) and 95% confidence intervals (CIs) for DCM development. RESULTS: The cohort, with an average age of 56.2 years (SD, 8.1) and 47.4% male, was followed for a median of 12.6 years. During this period, 3,993 participants (1.1%) developed DCM. A significant inverse correlation was found between handgrip strength and DCM incidence (P for trend < 0.001), with decreasing HRs for DCM across quartiles of increasing grip strength: HRs were 0.70 (95% CI: 0.64-0.76), 0.62 (95% CI: 0.57-0.68), and 0.59 (95% CI: 0.54-0.66) for the second, third, and fourth quartiles, respectively. Participants with average or brisk walking paces had a lower DCM risk (HR, 0.55; 95% CI: 0.50-0.61 and HR, 0.48; 95% CI: 0.43-0.54) compared to slow walkers. The greatest risk reduction was in those with both higher handgrip strength and faster pace (HR, 0.39; 95% CI: 0.34-0.44). CONCLUSIONS: Handgrip strength and walking pace are inversely associated with DCM incidence, suggesting their potential as cost-effective screening tools for identifying individuals at risk for DCM.

Adherence to the Mediterranean diet is associated with handgrip strength in postmenopausal women.

OBJECTIVE: This study aimed to assess the possible association of adherence to the Mediterranean diet (MD) with muscle strength and body composition. METHODS: The cross-sectional study evaluated 112 postmenopausal women (aged 41-71 years). Fasting blood samples were obtained for biochemical/hormonal assessment. The Mediterranean Dietary Score (MedDietScore) was calculated and used to stratify adherence by tertiles (low [T1], moderate [T2] or high [T3]). Handgrip strength (HGS) was measured by dynamometry and body composition with dual-X-ray absorptiometry. RESULTS: Women with low-moderate MedDietScore (T1/T2) had lower HGS values than those with higher scores (19.5 ± 4.9 kg vs. 21.9 ± 3.9 kg, p = 0.023). A linear stepwise increase of HGS values per MedDietScore tertile was found (T1 vs. T2 vs. T3: 18.4 ± 4.4 kg vs. 20.6 ± 5.2 kg vs. 21.9 ± 3.9 kg, ANOVA p-value for linear trend = 0.009, ANCOVA p-value = 0.026). Multivariable models confirmed that HGS values were independently associated with the MedDietScore (ß-coefficient = 0.266, p = 0.010). Lean mass values were associated with the MedDietScore (ß-coefficient = 0.205, p = 0.040). All models were adjusted for age and cardiometabolic risk factors. CONCLUSIONS: The data suggest that the higher the adherence to the MD, the better the muscle strength and lean mass in postmenopausal women. Prospective studies are required to evaluate the significance of these observations in cardiovascular prevention strategies at midlife.

A demethylated lignin improved PVA-based supramolecular plastic with tough, degradable, and water-resistant performances.

Poly (vinyl alcohol) (PVA), as an excellent degradable plastic feedstock, is limited by its diminishing stability in wet environment, low strength, thermal instability and nonopaque properties. In response to these concerns, a PVA/demethylated lignin-based supramolecular plastic (DPVA-HA-Fe-5) was designed and produced from PVA, demethylated lignin (DL), humic acid (HA) and Fe3+ ions via a simple casting method. As compared with pure PVA plastic, the tensile strength of DPVA-HA-Fe-5 were increased by 411 % to 410.61 MPa, and the breaking strain was increased by 149 % to 239.47 %. Notably, the hydrophobicity of DPVA-HA-Fe-5 was also significantly improved. Although in highly humid environment (stored in RH = 100 % for 10 days) or in alkaline organic solvent (stored in pyridine for 3 h), DPVA-HA-Fe-5 also showed excellent mechanical strengths of 302.9 and 222.99 MPa, respectively, which are equivalent or even superior to the most of commercial petroleum-based plastics. Moreover, the prepared plastics showed an outstanding UV resistance and shading performance, and about 98.3 % protection against ultraviolet radiation B rays and 90.7 % protection against visible light were obtained. In short, the introduction of lignin to improve the performance of PVA-based plastic is a feasible method, and it could facilitate the development of high-value utilization of lignin.

Influence of Physical Activity on Health-Related Fitness in Young Adults: An Observational Research.

Background: Health-related fitness directly depends on the level of physical activity of the individual. Inactivity contributes to around 3.3% of all deaths, making the lack of exercise and sedentary lifestyles among the young generation a current source of concern. There is a paucity of research on the association between PA and health-related physical fitness among young people. In the perspective of this, the objective of this research was to find out the effect of PA levels on physical fitness in healthy adults. Methodology: A total of 419 students between the ages of 18 and 25 participated in this cross-sectional survey. The "Global Physical Activity Questionnaire (GPAQ)" was used to evaluate the PA. Their body fat percentage was measured using a skin fold caliper, followed by measurement of VO2max using a gas analyzer and hand grip strength and endurance assessment with the help of a computerized dynamometer. For statistical analysis, Karl Pearson's correlation coefficients and the ANOVA test were utilized. Results: PA was positively correlated with VO2 max (r=0.429), and handgrip strength (r=0.408) while negatively correlated with body fat % (r=-.315). VO2 max, body fat, and hand grip strength differ significantly amongst participants having different physical activity levels. (p-value =<0.05). Conclusion: This research concludes that PA is associated with physical fitness. PA will lead to a definite improvement in overall physical fitness. With the help of the results of this study, young adults can be motivated for physical fitness.

Effect of warm-up protocols using lower and higher loads on multiple-set back squat volume-load.

Background: The present study aimed to investigate the effects of post-activation performance enhancement (PAPE) after three warm-up protocols on back squat performance in trained men. Methods: Fourteen resistance-trained men performed conditioning activity (CA) with high-load (HL-CA), low-load (LL-CA), or usual specific warm-up as a control (CON). HL-CA consisted of one set of three repetitions with 90% of one repetition maximum (RM); LL-CA consisted of one set of six repetitions with 45% of 1 RM performed at maximal velocity; CON involved eight repetitions with 45% of 1 RM at controlled velocity. The participant's performance was measured using the total number of repetitions and volume load (reps × load × sets). Results: There were no significant differences between warm-up for the total number of repetitions (p = 0.17) or total volume load (p = 0.15). There was no difference between conditions for the number of repetitions (main condition effect; p = 0.17); however, participants achieved a significantly higher volume load after HL-PAPE than after CON for the first set (p = 0.04). Conclusion: High or low equated-load CA used as warm-up strategies did not potentiate subsequent performance enhancement in multiple-set back squat exercise performed until muscle failure in comparison with usual warm-up.

A Comparative Study of the Graston Technique and Alfredson Protocol in the Management of Achilles Tendinopathy.

BACKGROUND AND OBJECTIVES: The Achilles tendon, the largest and strongest tendon in the human body, is frequently injured by overuse; this condition is known as Achilles tendinopathy (AT). It serves as a link between the heel bone and the calf muscles and is necessary for motions, such as walking, sprinting, and jumping. Evidence is presented to support the efficacy of the Graston technique and Alfredson protocol for pain reduction and improvement of function and calf muscle strength. The objective of this study is to compare the efficacy of the Graston technique versus the Alfredson protocol in patients with AT. Methods and data collection: After obtaining approval from the ethical review board of the Rawalpindi Medical University, all patients fulfilling the inclusion criteria are divided into two groups, A and B, by generating random identity numbers using Microsoft Excel for allocation. Group A comprises patients who undergo treatment with the Graston technique as conventional therapy with Alfredson protocol (12-week calf muscle eccentric exercises), while those in group B follow a Graston technique with sole heel lift. Individuals in the eccentric exercises group follow an Alfredson method-based 12-week eccentric exercise plan for their leg muscles. The workouts need to be done twice a day, seven days a week for 12 weeks. The plan includes two exercises: the first done with the knee straightened to work the gastrocnemius and the second done with the knee bent to work the soleus. Three sets of 15 repetitions with no rest interval for each exercise are completed twice a day on the affected limb to yield functional improvement. RESULTS: The results showed that both the Alfredson protocol and the Graston technique were effective in managing AT symptoms. The study involved dividing 32 participants into two groups who received either treatment for four weeks. The main way to measure improvement was a score called the Villalta-Scanlon Achilles Tendonitis Index score. In both groups, these scores showed significant improvement (with a p-value less than 0.001, which means that the results are very statistically significant). For Group A (who received the Alfredson protocol), the average Villalta-Scanlon Achilles Tendonitis Index score before treatment was 29.25. This score increased to 31.25 at mid-treatment and 34.38 after the full four weeks of treatment. Group B (who received the Graston technique) started with an average Villalta-Scanlon Achilles Tendonitis Index score of 22.94. Their scores also increased throughout the treatment, reaching 34.94 at mid-treatment and 42.88 after four weeks. These findings provide evidence that both treatments can improve AT symptoms, with some suggestions that the Graston technique might be even more effective based on the higher average Villalta-Scanlon Achilles Tendonitis Index scores after treatment. CONCLUSIONS: The Graston technique shows promising results, particularly in the mid- and post-treatment phases, indicating its potential efficacy in comparison to the Alfredson protocol in the treatment of AT.

Effect of Fiber-Reinforced Composite Placement Site on Fracture Resistance of Premolar Teeth: An in vitro Study.

Background: This study aimed to investigate the fracture behavior of upper premolars with deep MOD cavities that were restored with Ribbond resin-reinforced fibers (FRCs) placed in different orientations. Methods: A total of 54 extracted maxillary premolars were randomly divided into nine groups. The experimental groups underwent MOD cavity preparation with or without root canal treatment, followed by FRCs placed in the pulpal floor, proximal walls, or both. Fracture resistance was tested using an Instron Machine. The samples were visually inspected to analyze the fracture mode. Results: The highest fracture resistance was observed in intact teeth (1299.98 ± 284.66 MPa). Placing Ribbond fibers in the pulpal floor (1155.86 ± 244.21 MPa) or the proximal walls (1077.56 ± 260.60 MPa) significantly improved fracture resistance (p= <0.05), compared to cavities restored with only resin composite (804.58 ± 93.34 MPa). However, placing Ribbond fibers in both the pulpal and proximal walls did not enhance fracture resistance. In the MOD-RCT groups, fracture resistance was improved only when Ribbond fibers were placed in the pulpal floor and the proximal walls. Fracture mode analysis revealed a combined fracture in most of the groups. Conclusion: This study concluded that using FRCs significantly improved the fracture resistance of MOD cavities in premolars and revealed that the placement site could be a determinant factor.

This study investigated the fracture behavior of upper premolars with deep MOD cavities restored with Ribbond resin-reinforced fibers (FRCs) placed in different orientations.Placing Ribbond fibers in the pulpal floor or the proximal walls significantly improved the fracture resistance of premolars with deep MOD cavities.In the MOD-RCT groups, fracture resistance was improved only when Ribbond fibers were placed in the pulpal floor and the proximal walls.Fracture mode analysis revealed a combined fracture in most of the groups. This study concluded that using FRCs significantly improved the fracture resistance of MOD cavities in premolars and revealed that the placement site could be a determinant factor.

High Strength UV-Resistant Composite Film of Fe3+-Coordination Lignin/PVA.

The literature on polyvinyl alcohol (PVA) films is extensive, however, these methods often necessitate intricate synthesis processes or the addition of plasticizers to modify the strength and water solubility of the PVA material. A high-strength UV radiation-resistant composite film by chelating Fe3+ with lignin and PVA, which exhibits excellent hydrolysis resistance is developed. This composite film is prepared simply by incorporating a small amount of dealkalized lignin (APPL) and ferric chloride (FeCl3) into PVA through a straightforward composite process. During the scanning test, it is noted that the film exhibits a high density of uniformly dispersed particles, endowing it with efficient ultraviolet absorption capabilities. The infrared and anti-dissolution tests reveal that the coordination of Fe3+ with lignin imparts an outstanding hydrolysis resistance to the film, obviating the need for any extender, curing agent, acid or base. The tensile fracture strength reaches an impressive 187.81Mpa in the tensile test. UV and indicator card tests unequivocally demonstrate that the film achieves a remarkable 100% anti-UV efficiency. This Fe3+ chelated lignin/PVA composite film, with its facile preparation, environmental sustainability, high strength, and outstanding anti-ultraviolet efficiency, can be deployed across diverse applications requiring robust protection against ultraviolet radiation.

Relationship of Handgrip Strength and Asymmetry with Walking Ability in Older Adults with Excess Adiposity.

When low muscle mass and impaired strength and physical function coexist with excess adiposity, it is termed sarcopenic obesity (SO). Handgrip strength (HGS) is a predictor of disability and mortality. Asymmetry in HGS, particularly ≥ 10% strength differences between hands, may indicate neuromuscular dysfunction observable prior to declines in maximal strength are detectedand therefore could be incorporated to identify those at risk of physical limitations and SO. This study compares HGS values and asymmetry in older adults with excess adiposity and evaluates their relationships with physical function. Baseline data from two previous pilot weight loss studies in 85 older adults with body mass index values ≥ 30 kg m-2 are included with measures of body composition, walking speed, and chair stand ability. Sixty-three participants met the criteria for SO. HGS correlated to gait speed (r = 0.22), distance walked (r = 0.40), chair stand time for 5 repetitions (r = 0.42) and during 30 s (r = 0.31). HGS asymmetry is only correlated to gait speed (r = 0.31) and there are no differences in physical function between those with and without asymmetry. Maximal HGS tests should continue to be used to screen for functional decline and disability.

Shear bond strength of orthodontic brackets to single-shade composite surfaces: An in-vitro comparative study of different surface preparations.

PURPOSE: The primary objective of this study was to determine which single-shade composite surface yielded clinically acceptable shear bond strength (SBS) to metal orthodontics brackets. The secondary objectives were to identify the best composite surface treatment to enhance SBS and determine which surface treatment produced the least surface damage at debond. METHODS: Forty dental composite samples were selected from four different manufacturers (n=160) and grouped by manufacturer, one standard multi-shade dental system (FilTek™ Supreme Ultra) and three single-shade dental composites systems (OmniChroma®, SimpliShade™ and Venus® Diamond One). Each group of forty samples was randomly divided into four sub-groups (n=10). Each sub-group was identified by the surface treatment used, hydrofluoric acid (HFA), micro-etching (MIC), or phosphoric acid (PA). Shear bond strength testing and adhesive remnant index (ARI) were performed. Statistical analyses included Kruskal-Wallis, Wilcoxon rank-sum, and two-factorial ANOVA. RESULTS: OmniChroma® had statistically significant lower shear bond strength than the other composite materials tested. The control groups had statistically significant lower shear bond strength than Group 1/HFA (P<0.001) and Group 2/MIC (P<0.001). Group 1/HFA had the lowest distribution ARI score overall, while MIC had the highest ARI score distributions. CONCLUSIONS: The results of this in-vitro study found that all tested composite materials achieved clinically acceptable shear bond strengths. The utilization of micro-etching produced higher SBS. Significant Adhesive Remnant Index scores (< 0.001) were only found for OmniChroma® without any surface preparation.

Effect of eco-friendly pervious concrete pavement with travertine waste and sand on the heavy metal removal and runoff reduction performance.

To address the negative environmental and economic impact of the large amounts of solid waste generated during travertine mining and to reduce the dependence on natural aggregates and cement for pervious concrete pavement applications, travertine waste, as aggregate and powder, was used for the travertine powder pervious concrete (TPPC) to improve the utilization of solid waste and decrease CO2 emissions. The experimental results showed that using 25% travertine aggregate and 5% powder results in a compressive strength reduction of only 9.8% to 25.92 MPa but a significant improvement in water permeability of 57.1% from 3.89 to 6.11 mm/s. To improve the performance of TPPC, further research was done on the effect of sand addition rate (SAR) on TPPC's density, compressive strength, porosity, water permeability, freeze-thaw resistance and heavy metal removal capacity to obtain an optimal incorporation ratio. As SAR rises, the compressive strength of TPPC with sand (STPC) initially increases and then decreases, while permeability behaves inversely. At 3% SAR, the compressive strength reached a maximum of 26.51 MPa, primarily due to the sand added to fill in some of the pores and stabilize the gradation. After 25 cycles, the strength loss rate of STPC varies from 11.39 to 17.93% and the freeze-thaw resistance is most excellent when SAR is 3%. The removal rate of heavy metals using the immersion method was found to be significantly higher (83.4-100%) compared to the rapid method (11.7-28.1%). Therefore, the 3% SAR was recommended for the mixture design of STPC. A laboratory-scale version of the pavement was constructed to assess the efficacy of STPC pavement (STPCP) in reducing runoff and removing heavy metals. The results showed that STPCP could remove more than 94% of runoff with varying intensities after 1 h. The STPCP exhibited removal rates ranging from 42.0 to 99.4% for Cd2+ and 79.5-95.4% for Cu2+. STPCP also attained a removal rate above 98% for Pb2+ after 30 min, demonstrating its environmental friendliness.

The water imbalance of skeletal muscle and muscle weakness in patients with heart failure.

AIMS: A high extracellular water (ECW) to intracellular water (ICW) ratio of skeletal muscle as assessed by bioelectrical impedance analysis is reportedly associated with loss of muscle strength. However, the validity of this index for heart failure (HF), which is likely associated with changes in the water distribution, is unclear. METHODS AND RESULTS: This study involved 190 patients with HF. The total ECW and ICW of both upper and lower extremities were measured, and a high ECW/ICW ratio was defined as an ECW/ICW ratio higher than the median (≥0.636 for men, ≥0.652 for women). Low muscle strength was defined as reduced handgrip strength according to the criteria established by the Asian Working Group for Sarcopenia. Patients with a high ECW/ICW ratio had a lower handgrip strength (21.1 ± 8.1 kg vs. 27.6 ± 9.3 kg, P ≤ 0.05) and 6 min walk distance (329 ± 116 m vs. 440 ± 114 m) than those with a low ECW/ICW ratio. An increasing ECW and/or decreasing ICW was associated with a higher ECW/ICW ratio and a lower handgrip strength (P < 0.05). In the multivariate logistic regression analysis, a high ECW/ICW ratio and low skeletal muscle mass were independently associated with low muscle strength (P < 0.05). CONCLUSIONS: A high ECW/ICW ratio in limb muscles, that is, the water imbalance of increasing ECW and/or decreasing ICW, is useful in assessing muscle quality in patients with HF.

Comparative Assessment of the Shear Bond Strength of Ceramic Brackets Bonded to the Enamel Surface with a Self-adhesive System.

Objectives: This study aimed to evaluate the shear bond strength of ceramic brackets bonded to the enamel surface using Vertise Flow, with or without the application of phosphoric acid. Materials and Methods: Forty-five extracted human premolar teeth were randomly assigned to three groups (N=15) based on the adhesive used for bonding: 1) Transbond XT, etch, and bond; 2) Vertise Flow; 3) Etch and Vertise Flow. After a 500-round thermocycling procedure, the shear bond strength was measured using a universal testing machine. The samples were then evaluated under a stereomicroscope to determine failure modes, and the Adhesive Remnant Index (ARI) was measured for each group. The data were analyzed with one-way ANOVA and post-hoc Tamhane at a significance level of P<0.05. Results: The highest shear bond strength values were observed in the Transbond XT (13.5±5.38MPa), acid etch and Vertise Flow (11.2±2.89MPa), and Vertise Flow (6.2±3.16MPa) groups, respectively, in descending order. The Vertise Flow group exhibited a significantly lower shear bond strength value compared to the other two groups, with no significant difference between the latter two. Conclusion: While all three study groups demonstrated clinically acceptable shear bond strength values, Vertise Flow showed lower values compared to the other two adhesives. The Vertise Flow composite resin system, whether used alone or with acid etching, remains a suitable choice for bonding ceramic brackets, offering the advantage of a simplified bonding procedure.

Maturation-specific enhancements in lower extremity explosive strength following plyometric training in adolescent soccer players: A systematic review and meta-analysis.

Background: For adolescent soccer players, good sprinting and jumping abilities are crucial for their athletic performance. The application of plyometric training on boosting explosive strength in adolescent soccer players is contingent upon the maturation phase, which can mediate the training-induced adaptations. Purpose: This systematic review and meta-analysis aim to explore the maturation effect of plyometric training on the lower limb explosive power of adolescent soccer players, with vertical countermovement jump (CMJ) and 20-m sprint as the main outcome indicators. Methods: An extensive search of the literature was carried out on various databases including PubMed, Web of Science, Scopus, ProQuest, and the China National Knowledge Infrastructure (CNKI), covering the time period from the establishment of each database to February 6, 2023. The search was conducted using English keywords such as 'Plyometric,' 'Adolescent,' 'football,' and 'Explosive strength.' This study utilized the Cochrane risk of bias assessment tool to conduct a standardized quality evaluation of all the included literature. Additionally, the Review Manager 5.4 software was employed to perform data analysis on all the extracted data. Results: A total of 17 studies involving 681 adolescent soccer players aged 10 to 19 were included. Plyometric training significantly improved CMJ performance across different maturation stages, especially in the post-peak height velocity stage (POST-PHV) [MD = 4.35, 95 % CI (2.11, 6.59), P < 0.01, I2 = 60 %]. The pre-peak height velocity stage (PRE-PHV) showed the next best improvement [MD = 3.00, 95 % CI (1.63, 4.37)], while the middle-peak height velocity stage (MID-PHV) showed the least improvement [MD = 2.79, 95 % CI (1.16, 4.41), P < 0.01, I2 = 49 %]. However, improvements in 20 m sprint ability were only observed in the PRE-PHV [MD = -0.06, 95 % CI (-0.12, 0), P < 0.01, I2 = 0 %] and MID-PHV [MD = -0.18, 95 % CI (-0.27, -0.08), P < 0.01, I2 = 0 %] stages. Conclusion: Plyometric training serves as a potent strategy for boosting the lower limb explosive strength of adolescent soccer players, and the training effect is closely related to the players' biological maturity. Considering biological maturity is a key aspect that this study deems essential for the formulation of effective training programs for these adolescent players.

The Effects of Whole-Body Vibration Therapy in Weight-Bearing and Non-Weight-Bearing Positions for Upper and Lower Extremities on Balance and Function in Cerebral Palsy Children: A Randomized Controlled Trial.

Background and objective Cerebral palsy (CP) is one of the most prevalent neurological conditions affecting children; it is characterized by poor motor control, restricted range of motion (ROM), and poor balance. While whole-body vibration therapy (WBVT) has been used to treat these symptoms, its efficacy in different configurations remains unexplored. Hence, this study aimed to determine and compare the effects of WBVT applied to either the upper extremities, lower extremities, or both upper and lower extremities in weight-bearing and non-weight-bearing positions on ROM (shoulders, elbows, wrists, hips, knees, and ankle joints), balance, and function in children with spastic hemiplegic CP. Methods This randomized clinical trial involved 60 hemiplegic spastic CP children aged 5-15 years. After randomization, all the participants were divided into six groups of equal size based on the WBVT application for upper extremities, lower extremities, or both in weight-bearing or non-weight-bearing positions. The therapy was applied three times per week for four consecutive weeks. The outcome measures were ROM, hand grip strength, balance quantification score using My Fitness Trainer (MFT) 2.0, and timed up and go (TUG) scores. Results While all the groups were homogenous before treatment, after treatment, it was observed that all the ranges improved significantly in all groups. The same was observed for hand grip strength, balance score, and TUG test scores (p<0.05). The post-hoc analysis revealed that the weight-bearing position for the upper and lower extremities combined showed the highest level of improvement. Conclusions Based on our findings, WBVT in weight-bearing positions produces more significant results than in non-weight-bearing positions. We also observed that when WBVT is applied to the upper extremities, it can improve the function of the lower extremities and vice versa.

Comparing the acute responses between a manual and automated blood flow restriction system.

The purpose of this study was to compare acute responses between manual and automated blood flow restriction (BFR) systems. Methods: A total of 33 individuals completed this study. On visit 1, arterial occlusion pressure (AOP, mm Hg), cardiovascular responses, and discomfort (RPE-D) were measured with each BFR system at rest. On visit 2, unilateral bicep curls were completed [30% one-repetition maximum; 50% AOP] with one system per arm. Muscle thickness (MT, cm) and maximal force (N) were assessed before (pre), immediately (post-0), 5 min (post-5), and 10 min (post-10) post-exercise. Ratings of perceived exertion (RPE-E) and ratings of perceived discomfort (RPE-D) were assessed throughout the exercise. AOP and repetitions were compared with Bayesian paired t-tests. Other outcomes were compared with Bayesian RMANOVAs. BF10 represents the likelihood of the best model vs. the null. The results are presented as mean ± SD. Results: Supine cardiovascular responses and RPE-D were similar for manual and automated (all BF10 ≤ 0.2). Supine AOP for manual (157 ± 20) was higher than that of automated (142 ± 17; BF10 = 44496.0), but similar while standing (manual: 141 ± 17; automated: 141 ± 22; BF10 = 0.2). MT (time, BF10 = 6.047e + 40) increased from Pre (3.9 ± 0.7) to Post-0 (4.4 ± 0.8; BF10 = 2.969e + 28), with Post-0 higher than Post-5 (4.3 ± 0.8) and Post-10 (4.3 ± 0.8; both BF10 ≥ 275.2). Force (time, BF10 = 1.246e + 29) decreased from Pre (234.5 ± 79.2) to Post-0 (149.8 ± 52.3; BF10 = 2.720e + 22) and increased from Post-0 to Post-5 (193.3 ± 72.7; BF10 = 1.744e + 13), with Post-5 to Post-10 (194.0 ± 70.6; BF10 = 0.2) being similar. RPE-E increased over sets. RPE-D was lower for manual than automated. Repetitions per set were higher for manual (Set 1: 37 ± 18; Set 4: 9 ± 5) than automated (Set 1: 30 ± 7; Set 4: 7 ± 3; all BF10 ≥ 9.7). Conclusion: Under the same relative pressure, responses are mostly similar between BFR systems, although a manual system led to lower exercise discomfort and more repetitions.

The mechanism of static postural control in the impact of lower limb muscle strength asymmetry on gait performance in the elderly.

Background: Abnormal gait is prevalent among the elderly population, leading to reduced physical activity, increased risk of falls, and the potential development of dementia and disabilities, thus degrading the quality of life in later years. Numerous studies have highlighted the crucial roles of lower limb muscle strength asymmetry and static postural control in gait, and the reciprocal influence of lower limb muscle strength asymmetry on static postural control. However, research exploring the interrelationship between lower limb muscle strength asymmetry, static postural control, and gait performance has been limited. Methods: A total of 55 elderly participants aged 60 to 75 years were recruited. Isokinetic muscle strength testing was used to assess bilateral knee extension strength, and asymmetry values were calculated. Participants with asymmetry greater than 15% were categorized as the Asymmetry Group (AG), while those with asymmetry less than 15% were classified in the Symmetry Group (SG). Gait parameters were measured using a plantar pressure gait analysis system to evaluate gait performance, and static postural control was assessed through comfortable and narrow stance tests. Results: First, participants in the AG demonstrated inferior gait performance, characterized by slower gait speed, longer stance time and percentage of stance time in gait, and smaller swing time and percentage of swing time in gait. Spatial-temporal gait parameters of the weaker limb tended to be abnormal. Second, static postural control indices were higher in AG compared to SG in all aspects except for the area of ellipse during the comfortable stance with eyes open test. Third, abnormal gait parameters were associated with static postural control. Conclusion: Firstly, elderly individuals with lower limb muscle strength asymmetry are prone to abnormal gait, with the weaker limb exhibiting poorer gait performance. Secondly, lower limb muscle strength asymmetry contributes to diminished static postural control in the elderly. Thirdly, the mechanism underlying abnormal gait in the elderly due to lower limb muscle strength asymmetry may be linked to a decline in static postural control.