Muscle Strength Gain Research Articles

Outcome of a Physical Rehabilitation Program on Functionality and Impact on Quality of Life in Postoperative Liver Transplant Patients: A Systematic Review

Objectives: To conduct a systematic review of the literature on the outcomes of a physical rehabilitation program on functionality and identify possible impacts on quality of life in patients after liver transplantation. Methods: Controlled clinical trials and observational studies were selected from the PubMed, SciELO, and BIREME databases that "t the PICO (P – population; I – intervention; C – comparison; O – outcomes) question “what are the bene"ts of a physical rehabilitation program on functionality and quality of life outcomes in patients undergoing liver transplantation?” Studies written in English, Portuguese, and Spanish, published in the last 10 years were selected. After selection, the Physiotherapy Evidence Database (PEDro) scale was used to perform the methodological evaluation of the studies. Results and Discussion: A total of "ve interventionist articles were selected, most of which had good methodological quality. Only one study did not associate resistance training with aerobic exercises, but all had signi"cant results regarding increased functional capacity and reduced perception of fatigue after liver transplantation. Conclusion: !e studies indicated that the association of a resistance training program associated with aerobic training is bene"cial in terms of muscle strength gain, exercise capacity, and perception of fatigue.

Vitamin D Supplementation Does Not Enhance Gains in Muscle Strength and Lean Body Mass or Influence Cardiorespiratory Fitness in Vitamin D-Insufficient Middle-Aged Men Engaged in Resistance Training.

This study checked whether vitamin D (Vit-D) supplementation improves the efficacy of resistance training (RT) in terms of increasing muscle strength and lean body mass (LBM), and influencing cardiorespiratory fitness (VO2max) in Vit-D-deficient middle-aged healthy men. Participants (n = 28) were quasi-randomly assigned to one of two groups, which, in a double-blind manner, supplemented their diet daily with either Vit-D (8000 IU; VD) or placebo (PLC) during participation in a 12-week supervised RT program. During the intervention, serum Vit-D concentrations increased 2.6-fold (p < 0.001) in the VD group, while no changes occurred in the PLC group. Muscle strength gains (p < 0.001) as measured in seven exercises performed on RT equipment and increases (p < 0.001) in LBM were similar in the two groups. Total fat mass, percent total fat, and percent android fat decreased (p < 0.05) to a similar extent in both groups, but there was no change in VO2max in either group. In conclusion, in healthy Vit-D-insufficient middle-aged men engaged in resistance training, Vit-D supplementation increases serum 25(OH)D levels but does not enhance gains in muscle strength and LBM, or decreases in fat mass and fat percentage, and does not affect cardiorespiratory fitness.

Muscle memory in humans: evidence for myonuclear permanence and long-term transcriptional regulation after strength training.

The objective of this work was to investigate myonuclear permanence and transcriptional regulation as mechanisms for cellular muscle memory after strength training in humans. Twelve untrained men and women performed 10weeks of unilateral elbow-flexor strength training followed by 16weeks of de-training. Thereafter, 10weeks' re-training was conducted with both arms: the previously trained arm and the contralateral untrained control arm. Muscle biopsies were taken from the trained arm before and after both training periods and from the control arm before and after re-training. Muscle biopsies were analysed for fibre cross-sectional area (fCSA), myonuclei and global transcriptomics (RNA sequencing). During the first training period, myonuclei increased in type 1 (13 ± 17%) and type 2 (33 ± 23%) fibres together with a 30 ± 43% non-significant increase in mixed fibre fCSA (P=0.069). Following de-training, fCSA decreased in both fibre types, whereas myonuclei were maintained, resulting in 33% higher myonuclear number in previously trained vs. control muscle in type 2 fibres. Furthermore, in the previously trained muscle, three differentially expressed genes (DEGs; EGR1, MYL5 and COL1A1) were observed. Following re-training, the previously trained muscle showed larger type 2 fCSA compared to the control (P=0.035). However, delta change in type 2 fCSA was not different between muscles. Gene expression was more dramatically changed in the control arm (1338 DEGs) than in the previously trained arm (822 DEGs). The sustained higher number of myonuclei in the previously trained muscle confirms myonuclear accretion and permanence in humans. Nevertheless, because of the unclear effect on the subsequent hypertrophy with re-training, the physiological benefit remains to be determined. KEY POINTS: Muscle memory is a cellular mechanism that describes the capacity of skeletal muscle fibres to respond differently to training stimuli if the stimuli have been previously encountered. This study overcomes past methodological limitations related to the choice of muscles and analytical procedures. We show that myonuclear number is increased after strength training and maintained during de-training. Increased myonuclear number and differentially expressed genes related to muscle performance and development in the previously trained muscle did not translate into a clearly superior responses during re-training. Because of the unclear effect on the subsequent hypertrophy and muscle strength gain with re-training, the physiological benefit remains to be determined.

Isokinetic Knee Strengthening Impact on Physical and Functional Performance, Pain Tolerance, and Quality of Life in Overweight/Obese Women with Patellofemoral Pain Syndrome.

Background/Objectives: Patellofemoral syndrome is a common osteoarticular condition that affects many individuals. Various treatment options are available, with a significant emphasis on targeted muscle-strengthening exercises. The purpose of this study was to investigate the effect of isokinetic muscle strengthening on muscle strength, joint range of motion, quality of life, physical performance, and pain tolerance in overweight/obese women with patellofemoral syndrome. Methods: Twenty-four overweight or obese women with patellofemoral syndrome participated in the study during September and October 2023 in a private medical facility for physical medicine and functional rehabilitation. They were randomly assigned to one of two groups for six weeks of isokinetic muscle strengthening. The first group (ISO.G) followed a rehabilitation program combined with isokinetic muscle strengthening. A second group (PCM.G) followed a rehabilitation program that includes an isokinetic protocol in passive compensation movement. The extensors' peak torque was measured before and after training. Results: The flexors' peak torque, stair climbing test, 10 m walk, chair lift, monopodal support, goniometric knee flexion test, heel-buttock distance measurement, pain, and quality of life scores improved significantly in both groups. The ISO.G, on the other hand, benefited from a significant increase in quadriceps muscle strength revealed by the extensors' peak torque. Conclusions: For the treatment of patellofemoral syndrome, isokinetic muscle strengthening in concentric mode appears to have a significant advantage over the classic rehabilitation program with isokinetic passive compensation, particularly in muscle strength gain, in addition to the improvement of joint range of motion, quality of life, physical performance, and pain tolerance. Isokinetic training may be recommended as a beneficial approach for the rehabilitative treatment of patellofemoral pain syndrome in overweight/obese women.

Effects of stretching on muscle strength, endurance, and power performance: A systematic review and meta-analysis

BACKGROUND: The acute and chronic effects of stretching preceding exercises on strength, power and muscular endurance are still not entirely clear in the literature. OBJECTIVE: To verify the acute and chronic effects of the main types of stretching (static, dynamic, PNF, and ballistic) on muscle strength, power, and endurance. METHODS: A systematic literature search was performed in: PubMed, Web of Science, LILACS, Scopus, Science Direct, and CENTRAL. The methodological quality was assessed using the PEDro scale. Meta-analysis were performed using the standardized mean difference (SMD). RESULTS: 43 studies were included in the systematic review and 30 in the meta-analysis calculations. Only two studies showed high methodological quality. In general, static stretching had an impact on the potentiated the gain in muscle strength of the lower limbs in the long term (0.60 [0.20–1.00]). The acute (ES = 0.38 [0.05–0.70]) and long-term (ES = 1.04 [0.21–1.88]) dynamic stretching was able to potentiate the gain of muscle power in the lower limbs, while the acute PNF had an impact on the worsening of the muscular endurance (ES = 1.68 [0.83–2.53]). CONCLUSIONS: When the training objective is linked to acute effects, dynamic stretching should be prioritized before the main activity. For long-term effects, static and dynamic stretching have been shown to potentiate muscle strength and power gain, respectively, and are recommended in these cases.

Electromyographic activity of the ankle and foot during functional exercises and traditional exercises

IntroductionTraditional exercises using an elastic band are often standard in clinical practice to gain muscle strength. Additionally, functional exercises are considered more representative of functional tasks or sport. However, it is unclear whether functional exercises are comparable to traditional exercises in activating the ankle joint and foot. ObjectiveThe purpose of this study was to analyze the effects of functional exercise and traditional exercise on the muscle activity of the ankle joint and foot. MethodsThirty women participated in this study. Using surface electromyographic, muscle activation of the Tibialis Anterior (TA), Peroneus Longus (FL), Peroneus Short (FC), Gastrocnemius Medialis (GM) and Flexor Digitorum Shortus (FCD) was measured in nine exercises (dorsiflexion with an elastic band, plantar flexion with an elastic band, inversion with an elastic band, eversion with an elastic band, towel curl, standing plantar flexion, squats with an elastic band on the foot, diagonal propulsion and propulsion with peroneal stimulation). The muscle activation was normalized by the activation in maximum voluntary isometric contraction. ResultsFunctional exercises showed larger mean EMG amplitudes than the traditional exercises for all muscle groups (p > 0.05). ConclusionFunctional exercises provoked more activation compared with the traditional exercises. Functional exercises can be indicated to improve muscle function and functional task performance in populations that suffer dysfunction in ankle joint and foot.

Cerebral cortex activation and functional connectivity during low-load resistance training with blood flow restriction: An fNIRS study.

Despite accumulating evidence that blood flow restriction (BFR) training promotes muscle hypertrophy and strength gain, the underlying neurophysiological mechanisms have rarely been explored. The primary goal of this study is to investigate characteristics of cerebral cortex activity during BFR training under different pressure intensities. 24 males participated in 30% 1RM squat exercise, changes in oxygenated hemoglobin concentration (HbO) in the primary motor cortex (M1), pre-motor cortex (PMC), supplementary motor area (SMA), and dorsolateral prefrontal cortex (DLPFC), were measured by fNIRS. The results showed that HbO increased from 0 mmHg (non-BFR) to 250 mmHg but dropped sharply under 350 mmHg pressure intensity. In addition, HbO and functional connectivity were higher in M1 and PMC-SMA than in DLPFC. Moreover, the significant interaction effect between pressure intensity and ROI for HbO revealed that the regulation of cerebral cortex during BFR training was more pronounced in M1 and PMC-SMA than in DLPFC. In conclusion, low-load resistance training with BFR triggers acute responses in the cerebral cortex, and moderate pressure intensity achieves optimal neural benefits in enhancing cortical activation. M1 and PMC-SMA play crucial roles during BFR training through activation and functional connectivity regulation.

Resistance Training-Induced Gains in Muscle Strength and Power Mediate the Improvement in Walking Speed in Middle-Aged Women Who Are Breast Cancer Survivors.

Santagnello, SB, Martins, FM, de Oliveira Junior, GN, de Sousa, JdeFR, Nomelini, RS, Murta, EFC, and Orsatti, FL. Resistance training-induced gains in muscle strength and power mediate the improvement in walking speed in middle-aged women who are breast cancer survivors. J Strength Cond Res 38(4): 773-782, 2024-(a) Ascertain whether lower muscle mass, strength (1 repetition maximum [1RM]), and power (Pmax) in middle-aged women who are breast cancer survivors (BCS), when compared with women of a similar age never diagnosed with cancer (WNC), are related with lower walking speed (WS). (b) Ascertain whether changes in WS are associated with changes in muscle mass, 1RM, and (or) Pmax after resistance training (RT) in middle-aged BCS. A cross-section study was performed. Twenty WNC and 21 BCS were evaluated for lean mass of legs (LLM), 1RM (knee extension), muscle quality index (MQI = 1RM/LLM), Pmax (maximum muscle power-knee extension), and fast WS (10 and 400-meters). Randomized clinical trial was performed. The BCS were randomly divided into the control group ( n = 9) and the RT group ( n = 11). Breast cancer survivors exhibited lower 1RM (24.2%, p ˂ 0.001), Pmax (30.6%, p ˂ 0.001), MQI (22.2%, p = 0.001), and WS (10-m = 17.0%, p ˂ 0.001 and 400-m = 10.5%, p = 0.002) than WNC. Resistance training increased 1RM (31.6%, p = 0.001), MP (29.0%, p = 0.012), MQI (28.5%, p = 0.008), and WS (10-m = 9.4%, p = 0.009 and 400-m = 6.2%, p = 0.006) in BCS. The changes in WS were positively associated with 1RM (10-m = 68%, p = 0.001 and 400-m = 37%, p = 0.036) and Pmax (10-m = 56%, p = 0.005 and 400-m = 40%, p = 0.027) and MQI (10-m = 63%, p = 0.043 and 400-m = 37%, p = 0.035). Resistance training-induced gains in muscle strength and power mediate the improvement in WS in middle-aged BCS. Resistance training is an effective strategy to improve WS in middle-aged BCS.

Nutritional importance of animal-sourced foods in a healthy diet.

Animal-sourced foods, such as meats, poultry, eggs, milk, and fish are nutrient-dense foods that are rich sources of protein, essential amino acids, and micronutrients that can be challenging to obtain solely through plant-based foods. Animal-sourced protein foods provide crucial nutrients that support the growth and development in children, maintenance of muscle mass and function in adults, gain in muscle mass and strength in exercising individuals, and mitigation of sarcopenia in the elderly. The 2020-2025 Dietary Guidelines for Americans have identified the important role of animal-sourced foods in the diet at every stage of life. Animal-sourced foods are consumed worldwide and contribute to global food security.

Application Of Resistance Training And Strength Exercises For Improving Explosive Force In Students Of Sports University Of Tirana

Resistance training is a potent stimulus to the neuromuscular system for muscle hypertrophy and strength gain which is known to have positive effects on health, weight control and performance The capacity for human exercise performance can be enhanced with prolonged exercise training, whether it is endurance or strength-based. The purpose of this study is to analyse the effectiveness of RT performed with strength exercises for improving body composition, muscle strength and explosive force of SUT students. 45 male students of SUT, aged 18-25 years old, had participated in this study. The training period lasted 12 weeks with 3 times per week sessions. The study was performed following a training protocol by control and experimental groups. The paired samples t-test was used to the comparisons within group, whilst the independent samples t-test was used to compare variables between groups at baseline. The main findings of this study is that HIRT procedures improvements in the maximum power output (peak power) and efficiency of the motion at experimental group are slightly greater than those reported at control group and the estimated mean change in maximum power output and efficiency over the training program was 4.08 W/kg and 4.2% efficiency (p &lt; 0.05) when compared the experimental group to control group. In conclusion, the present study suggest that, the high intensity resistance training program composed by functional training, fitness challenge and core &amp; abdominal exercises have the most benefit form improving body composition, peak maximum power, efficiency and explosive force.

Effects of a 20-Week High-Intensity Strength Training Program on Muscle Strength Gain and Cardiac Adaptation in Untrained Men: Preliminary Results of a Prospective Longitudinal Study.

As strength sports gain popularity, there is a growing need to explore the impact of sustained strength training on cardiac biventricular structure and function, an area that has received less attention compared to the well-established physiological cardiac adaptation to endurance training. This study aims to implement a 20-week high-intensity strength training program to enhance maximal muscle strength and evaluate its impact on cardiac biventricular adaptation in healthy, untrained men. A total of 27 healthy and untrained young men (mean age 22.8, SD 3.2 years) participated in a strength training program designed to increase muscle strength. The training program involved concentric, eccentric, and isometric exercise phases, conducted over a consecutive 20-week time frame with a frequency of 3 weekly training sessions. Participants were evaluated before and after 12 and 20 weeks of training through body composition analysis (bioelectrical impedance), a 12-lead resting electrocardiogram, 3D transthoracic echocardiography, cardiopulmonary exercise testing, and muscle isokinetic dynamometry. The progression of strength training loads was guided by 1-repetition maximum (RM) testing during the training program. Of the initial cohort, 22 participants completed the study protocol. No injuries were reported. The BMI (mean 69.8, SD 10.8 kg/m² vs mean 72, SD 11 kg/m²; P=.72) and the fat mass (mean 15.3%, SD 7.5% vs mean 16.5%, SD 7%; P=.87) remained unchanged after training. The strength training program led to significant gains in 1-RM exercise testing as early as 4 weeks into training for leg extension (mean 69.6, SD 17.7 kg vs mean 96.5, SD 31 kg; P<.001), leg curl (mean 43.2, SD 9.7 kg vs mean 52.8, SD 13.4 kg; P<.001), inclined press (mean 174.1, SD 41.1 kg vs mean 229.2, SD 50.4 kg; P<.001), butterfly (mean 26.3, SD 6.2 kg vs mean 32.5, SD 6.6 kg; P<.001), and curl biceps on desk (mean 22.9, SD 5.2 kg vs mean 29.6, SD 5.2 kg; P<.001). After 20 weeks, the 1-RM leg curl, bench press, pullover, butterfly, leg extension, curl biceps on desk, and inclined press showed significant mean percentage gains of +40%, +41.1%, +50.3%, +63.5%, +80.1%, +105%, and +106%, respectively (P<.001). Additionally, the isokinetic evaluation confirmed increases in maximal strength for the biceps (+9.2 Nm), triceps (+11.6 Nm), quadriceps (+46.8 Nm), and hamstrings (+25.3 Nm). In this paper, only the training and muscular aspects are presented; the cardiac analysis will be addressed separately. This study demonstrated that a short-term high-intensity strength training program was successful in achieving significant gains in muscle strength among previously untrained young men. We intend to use this protocol to gain a better understanding of the impact of high-intensity strength training on cardiac physiological remodeling, thereby providing new insights into the cardiac global response in strength athletes. ClinicalTrials.gov NCT04187170; https://clinicaltrials.gov/study/NCT04187170.

Late Results of Early End-to-End Repair in Sciatic Nerve Injuries.

Mechanisms of sciatic nerve injury include gunshot injury, sharps injury, injection injury, contusion, femoral fracture injury, and iatrogenic injury due to fracture surgery. Regardless of the type of injury, patients undergoing sciatic nerve repair have poor motor and sensory outcomes. In this study, we compared the late outcomes of a group of patients in whom the author performed an early end-to-end anastomosis for sciatic nerve sharps injury and another group of patients with a similar injury who were not operated on but left to natural history. The sciatic nerve, comprising two primary divisions with distinct muscle innervations, was subject to separate examinations. Group 1 (n=10, study group) underwent tibial division anastomosis, while Group 2 (n=12, control group) received no surgical intervention involving the tibial division. Similarly, Group 3 (n=11, study group) underwent peroneal division anastomosis, while Group 4 (n=14, control group) encompassed subgroups that did not undergo peroneal division surgery. In Group 1, the rate of gain in plantar flexion muscle strength was significantly higher (p < 0.05) compared to Group 2. Furthermore, the sensory examination gain level ratio within the tibial domain was significantly greater (p < 0.05) in Group 1 than in Group 2. Additionally, Group 1 exhibited a significantly higher rate (p < 0.05) of detection of regeneration and reinnervation findings in electromyography (EMG) compared to Group 2. When evaluating the long-term outcomes following early end-to-end anastomoses of the sciatic nerve, it becomes evident that while significant improvements are observed when compared to individuals without anastomosis, the positive impact of surgical interventions on motor and sensory gains in daily life remains limited. Nevertheless, we contend that early surgical intervention holds potential advantages in terms of patient management.

Effects of Acute Loading Induced Fatigability, Acute Serum Hormone Responses and Training Volume to Individual Hypertrophy and Maximal Strength during 10 Weeks of Strength Training

This study investigated whether a strength training session-induced acute fatigue is related to individuals’ strength training adaptations in maximal force and/or muscle hypertrophy, and whether acute responses in serum testosterone (T) and growth hormone (GH) concentrations during the training sessions would be associated with individual neuromuscular adaptations. 26 males completed the 10-week strength-training intervention, which included fatiguing dynamic leg press acute loading bouts (5 x 10 RM) at weeks two, four, six, and ten. Blood samples were collected before and after the loading and after 24h of recovery for serum T, GH, and cortisol (C) concentrations at weeks 2, 6, and 10. The cross-sectional area of the vastus lateralis was measured by ultrasonography. Isometric force measurements were performed before and immediately after loadings, and loading-induced acute decrease in maximal force was reported as the fatigue percentage. The subjects were split into three groups according to the degree of training-induced muscle hypertrophy after the training period. Increases in isometric force were significant for High Responders (HR, n = 10) (by 24.3 % ± 17.2, p = 0.035) and Medium Responders (MR, n = 7) (by 23.8 % ± 5.5, p = 0.002), whereas the increase of 26.2 % (±16.5) in Low Responders (LR, n = 7) was not significant. The amount of work (cm + s) increased significantly at every measurement point in all the groups. A significant correlation was observed between the fatigue percentage and relative changes in isometric force after the training period for the whole group (R = 0.475, p = 0.022) and separately only in HR (R = 0.643, p = 0.049). Only the HR group showed increased acute serum GH concentrations at every measurement point. There was also a significant acute increase in serum T for HR at weeks 6 and 10. HR showed the strongest correlation between acute loading-induced fatigue and isometric force gains. HR was also more sensitive to acute increases in serum concentrations of T and GH after the loading. Acute fatigue and serum GH concentrations may be indicators of responsiveness to muscle strength gain and, to some extent, muscle hypertrophy.

Effects of Acute Loading Induced Fatigability, Acute Serum Hormone Responses and Training Volume to Individual Hypertrophy and Maximal Strength during 10 Weeks of Strength Training.

This study investigated whether a strength training session-induced acute fatigue is related to individuals' strength training adaptations in maximal force and/or muscle hypertrophy, and whether acute responses in serum testosterone (T) and growth hormone (GH) concentrations during the training sessions would be associated with individual neuromuscular adaptations. 26 males completed the 10-week strength-training intervention, which included fatiguing dynamic leg press acute loading bouts (5 x 10 RM) at weeks two, four, six, and ten. Blood samples were collected before and after the loading and after 24h of recovery for serum T, GH, and cortisol (C) concentrations at weeks 2, 6, and 10. The cross-sectional area of the vastus lateralis was measured by ultrasonography. Isometric force measurements were performed before and immediately after loadings, and loading-induced acute decrease in maximal force was reported as the fatigue percentage. The subjects were split into three groups according to the degree of training-induced muscle hypertrophy after the training period. Increases in isometric force were significant for High Responders (HR, n = 10) (by 24.3 % ± 17.2, p = 0.035) and Medium Responders (MR, n = 7) (by 23.8 % ± 5.5, p = 0.002), whereas the increase of 26.2 % (±16.5) in Low Responders (LR, n = 7) was not significant. The amount of work (cm + s) increased significantly at every measurement point in all the groups. A significant correlation was observed between the fatigue percentage and relative changes in isometric force after the training period for the whole group (R = 0.475, p = 0.022) and separately only in HR (R = 0.643, p = 0.049). Only the HR group showed increased acute serum GH concentrations at every measurement point. There was also a significant acute increase in serum T for HR at weeks 6 and 10. HR showed the strongest correlation between acute loading-induced fatigue and isometric force gains. HR was also more sensitive to acute increases in serum concentrations of T and GH after the loading. Acute fatigue and serum GH concentrations may be indicators of responsiveness to muscle strength gain and, to some extent, muscle hypertrophy.

The Effect of Twelve-Week Karate and Salsa Dance Training on the Physical Fitness Performance of University Students

This study was performed to determine the effect of 12-weeks Karate and Salsa Dance training on the physical fitness performances of university students. A total of 124 students (age: 21.35 ± 1.59 year; height: 1.70 ± 0.08 cm; body weight: 67.1 ± 10.78 kg) have voluntarily participated in the study. The participants were divided into three groups using a random coin toss. The numbers of Karate group (KG), the Salsa Dance Group (SDG) and Control Group (COG) are 43 people (20 female, 23 male), 40 people (17 female, 23 male) and 41 people (12 female, 29 male), respectively. Technical training programs including two days a week and 90 minutes a day for 12 weeks were applied to the KG and SDG members accepting to the study. Body weight, height measurement, BMI calculation, bass stick balance test, handgrip strength test in upper and lower extremity strength measurements, wall squat leg strength test and plate tapping test for movement speed were performed to all participants before and after 12 weeks training. Since the data did not show normal distribution, Kruskal Wallis test was used in more than two groups and Mann Whitney-U test was used in binary comparisons. Looking at the results of KG and SDG, it was found that the BMI and muscle strength values of KG were better than the SDG values (p= .00). It was determined that the static balance values of SDG were higher than KG (p= 0.00). However, there was no significant difference between the movement speed of both groups (p&amp;gt; .05). All physical fitness parameters of both groups were found to be better than COG. We can suggest that sedentary individuals can benefit from karate technique training in gaining muscle strength. In addition, we can emphasize that it may be more appropriate to use salsa dance training in the development of static balance.

Evaluation of pulsed electromagnetic field therapy to improve muscle strength and functional aspects in the elderly: A pilot study

Backgroung: Sarcopenia has been defined as a progressive and generalized disorder of skeletal muscle that involves accelerated loss of muscle mass and function. The prevalence of sarcopenia worldwide is up to 15% in healthy elderly, approximately 76% of acutely hospitalized elderly patients, and up to 69% of patients admitted for post-acute geriatric rehabilitation. The loss of muscle mass results in serious consequences and several chronic diseases and senility, characterized by functional losses, muscle weakness, loss of independence and increased risk of falls and death. Sarcopenia has been defined as a progressive and generalized muscle disorder. Here we investigate the effects of PEMF in muscle strength and functional capabilities of elderly sarcopenic patients. Methods. Fifteen elderly people of both sexes, aged between 65 and 80 years old, classified according to the degree of muscle weakness. The participants were submitted to PEMF therapy in 12 sessions three times a week with the following parameters. In the first two sessions, only submaximal contraction was applied during 30 min with a frequency of 5 Hz at the sport mode of the equipment. In the following 10 sessions we used cycles of Submaximal contractions – frequency of 5 Hz with 5s duration and Supramaximal contractions – frequency of 30 Hz with 5s duration. The intensity of the equipment was adjusted according to the sensitivity of the patient and session duration was 30 min. Results. the TUG functional tests showed a significant reduction in execution time, with an initial average of 40 ± 10s to 22 ± 6s after treatment sessions. The average increase in muscle strength was 27 ± 9% after PEMF treatment. Conclusions. This case series report is the first in the world scientific literature to demonstrate the effectiveness of PEMF (Supramaximus™) therapy in gaining muscle strength and functionality in elderly sarcopenic patients. PEMF therapy, at least for the treatment of sarcopenia in the elderly, can be considered as the definitive evolution of electrical currents, with greater effectiveness and acceptance by the patient.

Effects of Resistance Training in Individuals with Lower Limb Amputation: A Systematic Review

Individuals with lower-limb amputations may have a significant strength deficit. This deficit may be related to the stump length and can lead to changes in gait, reduced energy efficiency, walking resistance, altered joint load, and increased risk of osteoarthritis and chronic low back pain. This systematic review used the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines to examine the effects of resistance training in lower limb amputees. Interventions with resistance training and other training methods were sufficient to achieve muscle strength gain in muscles of the lower limbs, improved balance, and improvements in gait pattern and speed when walking. However, it was impossible to determine from the results whether resistance training was mainly responsible for these benefits or even whether the positive effects presented would be observed with only this training method. When combined with other exercises, interventions with resistance training made possible gains for this population. Accordingly, it is noteworthy that the main finding of this systematic review is that the effects may be different according to the level of amputation, with mainly transtibial and transfemoral amputations studied.

IMPACTOS DO TREINAMENTO DE FORÇA MUSCULAR EM JOVENS ATLETAS

ABSTRACT Introduction: Muscle strength is directly related to its cross-sectional area and the volume of its fibers, but there is no absolute linear relationship between hypertrophy and improvement in athletic performance. Under this complex perspective, muscle training strategies have been implemented to promote relevant muscle strength and improve overall athletic ability. Objective: Explore the impacts of muscle strength training on young athletes based on sport kinetic principles. Methods: we adopted the method of intragroup statistical comparison with body indexes of 10 volunteers undergoing muscle training focused on the core and lower limb set. Results: Muscle strength gain was effectively verified via electromyogram, and the test of athletic skills showed an evolution in jumping, balance, and reduction of wrong passes. Conclusion: Evidence-based muscle training can increase muscle strength and promote sports skill gain in young athletes. Level of evidence II; Therapeutic studies - investigation of treatment results.

Muscular strength, flexibility and balance analysis in women practicing ballet pilates

Introduction: Ballet Pilates is a way of associating Pilates principles with Classic Ballet movements. The exercises employ body weight as a load, they can be adapted according to physical condition of each one. In a short time of practice, it is possible to observe the results, such as reducing weight, increasing muscle strength and improving posture. Objective: Analyze the muscular strength, flexibility and balance of women who practice Ballet Pilates, comparing them as variables before and after two months of practicing the sport. Methodology: The present study is of intervention and field, of comparative character and quantitative nature. A survey included 14 volunteers practicing the sport, aged 20 to 50 years old, and a data collection was carry out at the Tiradentes University. Data were collect using the Lafayette isometric dynamometer, the Sanny analog fleximeter and the Arkipelago baropodometry platform. Results: According to a strength analysis, muscle gains were observe, especially in the quadriceps, gluteus and calves, with statistical statistics for right quadriceps (p = 0.008) and left gluteus (p = 0.021). In the flexibility variable, differences were observed before and after the activity execution, with positive impact on the following muscle groups: torso (p = 0.004), hip flexors (p &lt;0.001) and hamstrings (p &lt;0.001). No significant difference in balance was find, measured by baropodometry, after two months of performing the Ballet Pilates modality. Conclusion: It was find that the Ballet Pilates modality is capable of promoting muscle strength gain, being observe in the study participants, mainly in the quadriceps and gluteus muscle groups. In addition, it became the flexibility gain exhibited by practitioners of this activity, exerting a positive influence, especially on the torso, hip flexors and hamstrings. As for balance, very expressive results were not observed, due to fact that the students have already presented balance preservation.

Blood glucose kinetics during concentric and eccentric muscle contractions

Studies comparing the two classes of stimuli (concentric and eccentric) have shown differences in the improvement of cardiovascular, metabolic, and muscle strength gain. This is an experimental, quantitative, and prospective study that aimed to verify the effect of eccentric exercise on glycolytic consumption and kinetics. The blood glucose kinetics of 17 male subjects was evaluated during a treadmill exercise with a 10% declined floor and velocity that required a 60% metabolic activity of VO2max, for 30 minutes. Seventy-two hours later, the same subjects exercised on the treadmill with a 10% inclined floor and 60% VO2max, for 30 minutes. To quantify glucose, blood samples were collected before the exercise, every three minutes along the 30 minutes of physical activity, and five and 10 minutes after finishing the exercise. For the downward slope, there was a homogeneous group behavior for blood glucose dynamics during the exercise, which was characterized by a monotonic decrease of glucose levels until reaching a minimum value at experimental times between 20 and 30 min, followed by a progressive recovery toward initial values. For the acclivity condition, blood glucose dynamics did not follow such a homogeneous behavior. A set of different types of dynamics could be identified. Experimental data showed that the type of dynamics could be predicted, to some extent, by the basal blood glucose level of subjects. The type of floor slope (upward or downward) directly affected glycolytic consumption and kinetics for the individuals analyzed.