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1.
J Vis Exp ; (205)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38619246

RESUMO

The treatment of type 2 diabetes mellitus (T2DM) is a major difficulty in improving patient health. Exercise is one of the main interventions for T2DM. Static strength training is one of the key forms of traditional sports in China. Research shows that static strength training is an effective clinical method for T2DM intervention, but there is no experimental device suitable for static training in mice. One of the difficulties in moving from clinical to basic research is to design appropriate experimental devices. In order to further study the mechanism of static training intervention in T2DM, a simple method for making a static training device for mice is introduced in this paper. This device has the advantages of simple operation, cheap material, and high feasibility. Previous studies conducted under this protocol have shown that static training can effectively reduce blood glucose levels and improve the mitochondrial function of skeletal muscle cells in T2DM mice. The purpose of introducing this device is to promote research on the mechanism of traditional exercise in the intervention of T2DM and to lay a foundation for the quantitative intervention of exercise.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Treinamento de Força , Humanos , Animais , Camundongos , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Experimental/terapia , China , Mitocôndrias
2.
Nutrients ; 16(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38612975

RESUMO

Aging-related sarcopenia exerts harmful impacts on muscle mass, strength, and physical mobility. Protein supplementation has been demonstrated to augment efficacy of resistance training (RT) in elderly. This study compared the relative effects of different protein supplements on muscle mass, strength, and mobility outcomes in middle-aged and older individuals undergoing RT. A comprehensive search of online databases was performed to identify randomized controlled trials (RCTs) examining the efficacy of protein supplement plus RT in untrained community-dwelling adults, hospitalized, or institutionalized residents who suffered acute or chronic health conditions. Network meta-analysis (NMA) was performed using a frequentist method for all analyses. Treatment effects for main outcomes were expressed as standard mean difference (SMD) with 95% confidence interval (CI). We used the surface-under-the cumulative-ranking (SUCRA) scores to rank probabilities of effect estimation among all identified treatments. Meta-regression analyses were performed to identify any relevant moderator of the treatment efficacy and results were expressed as ß with 95% credible interval (CrI). We finally included 78 RCTs (5272 participants) for analyses. Among the six protein sources identified in this NMA, namely whey, milk, casein, meat, soy, and peanut, whey supplement yielded the most effective treatments augmenting efficacy of RT on muscle mass (SMD = 1.29, 95% CI: 0.96, 1.62; SUCRA = 0.86), handgrip strength (SMD = 1.46, 95% CI: 0.92, 2.00; SUCRA = 0.85), and walking speed (SMD = 0.73, 95% CI: 0.39, 1.07; SUCRA = 0.84). Participant's health condition, sex, and supplementation dose were significant factors moderating the treatment efficacy on muscle mass (ß = 0.74; 95% CrI: 0.22, 1.25), handgrip strength (ß = -1.72; 95% CrI: -2.68, -0.77), and leg strength (ß = 0.76; 95% CrI: 0.06, 1.47), respectively. Our findings suggest whey protein yields the optimal supplements to counter sarcopenia in older individuals undergoing RT.


Assuntos
Treinamento de Força , Sarcopenia , Idoso , Pessoa de Meia-Idade , Humanos , Metanálise em Rede , Vida Independente , Sarcopenia/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Suplementos Nutricionais , Músculos
3.
Physiol Rep ; 12(7): e15991, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38605421

RESUMO

Skeletal muscle mass is critical for activities of daily living. Resistance training maintains or increases muscle mass, and various strategies maximize the training adaptation. Mesenchymal stem cells (MSCs) are multipotent cells with differential potency in skeletal muscle cells and the capacity to secrete growth factors. However, little is known regarding the effect of intramuscular injection of MSCs on basal muscle protein synthesis and catabolic systems after resistance training. Here, we measured changes in basal muscle protein synthesis, the ubiquitin-proteasome system, and autophagy-lysosome system-related factors after bouts of resistance exercise by intramuscular injection of MSCs. Mice performed three bouts of resistance exercise (each consisting of 50 maximal isometric contractions elicited by electrical stimulation) on the right gastrocnemius muscle every 48 h, and immediately after the first bout, mice were intramuscularly injected with either MSCs (2.0 × 106 cells) labeled with green fluorescence protein (GFP) or vehicle only placebo. Seventy-two hours after the third exercise bout, GFP was detected only in the muscle injected with MSCs with concomitant elevation of muscle protein synthesis. The injection of MSCs also increased protein ubiquitination. These results suggest that the intramuscular injection of MSCs augmented muscle protein turnover at the basal state after consecutive resistance exercise.


Assuntos
Células-Tronco Mesenquimais , Treinamento de Força , Humanos , Masculino , Camundongos , Animais , Injeções Intramusculares , Proteínas Musculares/metabolismo , Atividades Cotidianas , Músculo Esquelético/metabolismo , Células-Tronco Mesenquimais/metabolismo
4.
Sci Rep ; 14(1): 7744, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565633

RESUMO

This study aimed to determine the effects of resistance training combined with a probiotic supplement enriched with vitamin D and leucine on sestrin2, oxidative stress, antioxidant defense, and mitophagy markers in aged Wistar rats. Thirty-five male rats were randomly assigned to two age groups (old with 18-24 months of age and young with 8-12 weeks of age) and then divided into five groups, including (1) old control (OC: n = 5 + 2 for reserve in all groups), (2) young control (YC: n = 5), (3) old resistance training (OR: n = 5), (4) old resistance training plus supplement (ORS: n = 5), and old supplement group (OS: n = 5). Training groups performed ladder climbing resistance training 3 times per week for 8 weeks. Training intensity was inserted progressively, with values equal to 65, 75, and 85, determining rats' maximal carrying load capacity. Each animal made 5 to 8 climbs in each training session, and the time of each climb was between 12 and 15 s, although the time was not the subject of the evaluation, and the climbing pattern was different in the animals. Old resistance plus supplement and old supplement groups received 1 ml of supplement 5 times per week by oral gavage in addition to standard feeding, 1 to 2 h post training sessions. Forty-eight hours after the end of the training program, 3 ml of blood samples were taken, and all rats were then sacrificed to achieve muscle samples. After 8 weeks of training, total antioxidant capacity and superoxide dismutase activity levels increased in both interventions. A synergistic effect of supplement with resistance training was observed for total antioxidant capacity, superoxide dismutase, and PTEN-induced kinase 1. Sestrin 2 decreased in intervention groups. These results suggest that resistance training plus supplement can boost antioxidant defense and mitophagy while potentially decreasing muscle strength loss.


Assuntos
Condicionamento Físico Animal , Probióticos , Treinamento de Força , Humanos , Idoso , Ratos , Masculino , Animais , Lactente , Pré-Escolar , Ratos Wistar , Antioxidantes/metabolismo , Treinamento de Força/métodos , Mitofagia , Condicionamento Físico Animal/fisiologia , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Músculo Esquelético/metabolismo
5.
Pediatr Phys Ther ; 36(2): 207-215, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568267

RESUMO

PURPOSE: To investigate the effects of inspiratory strength training on respiratory muscle strength, pulmonary function, and walking capacity in children with cerebral palsy, with Gross Motor Function Classification System I to III. METHODS: Searches were conducted in CINAHL, LILACS, MEDLINE, and Physiotherapy Evidence Database (PEDro) databases. The outcomes of interest were respiratory muscle strength, pulmonary function, and walking capacity. The quality was assessed by PEDro Scale. The Grading of Recommendations Assessment, Development, and Evaluation system was used to summarize the quality of evidence. RESULTS: Inspiratory strength training increased the strength of inspiratory muscles and may increase the strength of the expiratory muscles. No changes were observed in pulmonary function or walking capacity. CONCLUSIONS: This systematic review provides moderate-quality evidence that inspiratory strength training is effective for increasing inspiratory muscle strength in children with cerebral palsy. Benefits may be carried over to improving expiratory muscle strength but were not observed on pulmonary function or walking capacity.


Assuntos
Paralisia Cerebral , Treinamento de Força , Criança , Humanos , Caminhada , Força Muscular
6.
FASEB J ; 38(7): e23596, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38597350

RESUMO

Myokines, released from the muscle, enable communication between the working muscles and other tissues. Their release during physical exercise is assumed to depend on immune-hormonal-metabolic interactions concerning mode (endurance or resistance exercise), duration, and intensity. This meta-analysis aims to examine the acute changes of circulating myokines inducing immunoregulatory effects caused by a bout of resistance exercise and to consider potential moderators of the results. Based on this selection strategy, a systematic literature search was conducted for resistance exercise intervention studies measuring interleukin (IL-) 6, IL-10, IL-1ra, tumor necrosis factor (TNF-) α, IL-15, IL-7, transforming growth factor (TGF-) ß1, and fractalkines (FKN) before and immediately after resistance exercise in healthy individuals. Random-effects meta-analysis was performed for each myokine. We identified a moderate positive effect of resistance exercise for IL-6 and IL-1ra. Regarding IL-15 and TNF-α, small to moderate effects were found. For IL-10, no significant effect was observed. Due to no data, meta-analyses for IL-7, TGF-ß1, and FKN could not be performed. No moderators (training status, type of exercise, risk of bias, age, sex, time of day, exercise volume, exercise intensity, exercise dose) of the results were detected for all tested myokines. Taken together, this systematic review and meta-analysis showed immediate positive effects of an acute resistance exercise session on IL-6, IL-1ra, TNF-α, and IL-15 levels.


Assuntos
Interleucina-15 , Treinamento de Força , Humanos , Interleucina-15/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , 60635 , Proteína Antagonista do Receptor de Interleucina 1 , Fator de Necrose Tumoral alfa/metabolismo , Músculo Esquelético/metabolismo , Interleucina-7/metabolismo , Exercício Físico/fisiologia
7.
BMC Pediatr ; 24(1): 247, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594697

RESUMO

BACKGROUND: Sports practice during adolescence is important to enhance bone development, although it may provide different effects depending on the mechanical impact present in the sport. Besides, resistance training (RT) may also induce bone changes directly (via muscle contractions) and indirectly (via myokines). However, there have been no studies analyzing the longitudinal influence of engaging in sport with and without added mechanical load. Thus, this study aims to analyze the combined effects of sports participation and resistance training on areal bone mineral density (aBMD) accrual in adolescent athletes participating in swimming and impact sports for 12-months. METHODS: This was a 12-month longitudinal study. The sample comprised 91 adolescents (21 females) aged 10 to 18 years, engaged in impact sports (basketball, tennis, track & field, baseball and gymnastics, n = 66) and non-impact sport (swimming, n = 25). The sample was divided according to resistance training participation: impact sports only (n = 45), impact sports + resistance training (n = 21), swimming-only (n = 17) and swimming + resistance training (n = 8). aBMD and soft tissues were measured using dual-energy X-ray absorptiometry. Generalized linear models analysis was used for the resistance training (RT) x type of sport interaction in predicting aBMD changes overtime, adjusting for maturation, sex and baseline aBMD. RESULTS: After 12-months, all groups showed a significant increase in aBMD, except for the swimming groups (regardless of resistant training), which showed a significant loss in spine aBMD (-0.045 [-0.085 to -0.004] g/cm2 in swimming-only and - 0.047 [-0.073 to -0.021] g/cm2 in swimming + RT). In comparisons between groups, only swimming + RT group, compared with swimming-only group presented higher upper limbs aBMD (0.096 g/cm2 [0.074 to 0.118] in swimming + RT vs. 0.046 [0.032 to 0.060] g/cm2 in swimming only; p < 0.05) and whole body less head (WBLH) aBMD (0.039 [0.024 to 0.054] g/cm2 in swimming + RT vs. 0.017 [0.007 to 0.027] g/cm2 swimming-only; p < 0.05). CONCLUSION: Despite the significant gain in aBMD in all groups and body sites after 12-months, except for the spine site of swimmers, the results indicate that participation in RT seems to improve aBMD accrual in swimmers at the upper limbs and WBLH.


Assuntos
Treinamento de Força , Natação , Feminino , Adolescente , Humanos , Natação/fisiologia , Estudos Longitudinais , Densidade Óssea/fisiologia , Absorciometria de Fóton/métodos , Desenvolvimento Ósseo/fisiologia
8.
BMJ Open ; 14(4): e082192, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38643006

RESUMO

INTRODUCTION: With increasing life expectancy of older adult population, maintaining independence and well-being in later years is of paramount importance. This study aims to investigate the impact of three distinct interventions: cognitive training, resistance training and a combination of both, compared with an inactive control group, on cognitive performance, mobility and quality of life in adults aged ≥65 years. METHODS AND ANALYSIS: This trial will investigate healthy older adults aged ≥65 years living independently without cognitive impairments. Participants will be randomly assigned to one of four groups: (1) cognitive training, (2) resistance training, (3) combined cognitive and resistance training, and (4) control group (n=136 participants with 34 participants per group). The interventions will be conducted over 12 weeks. The cognitive training group will receive group-based activities for 45-60 min two times a week. The resistance training group exercises will target six muscle groups and the combined group will integrate cognitive tasks into the resistance training sessions. Primary outcomes are: Short Physical Performance Battery, Sit-to-Stand Test, Montreal Cognitive Assessment, Trail Making Test and Stroop Test combined with gait on a treadmill (dual task). Life satisfaction will be measured by the Satisfaction With Life Scale. Secondary outcomes encompass hand grip strength and the Functional Independence Measure. ETHICS AND DISSEMINATION: Ethical approval was provided by the local Ethics Committee at the University of Hamburg (no. 2023_009). Informed consent will be obtained from all study participants. The results of the study will be distributed for review and discussion in academic journals and conferences. TRIAL REGISTRATION NUMBER: DRKS00032587.


Assuntos
Treinamento de Força , Humanos , Idoso , Treinamento de Força/métodos , Força da Mão , Qualidade de Vida , Marcha , Cognição , Terapia por Exercício/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Psicol. conduct ; 32(1): 181-202, Abr 1, 2024. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-232228

RESUMO

El ejercicio físico en altos volúmenes y descontrolado puede generar dependencia psicológica y cambios en el estado de ánimo. La regulación emocional y el afecto negativo son procesos relevantes para el desarrollo de patrones adictivos. Este estudio analizó las diferencias en afecto negativo y regulación emocional en función del perfil de práctica del ejercicio físico; la relación entre la dependencia del ejercicio, la regulación emocional y el afecto negativo; y el papel mediador de la regulación emocional en dicha relación. Participaron 375 practicantes de deportes de resistencia. Las diferencias en los perfiles de práctica del ejercicio físico fueron significativas en todas las variables de estudio. La dependencia del ejercicio correlacionó de forma positiva y significativa con las dificultades de regulación emocional y con el afecto negativo. Las dificultades de regulación emocional fueron predictoras de la dependencia del ejercicio. Hubo un efecto de mediación de las dificultades de regulación emocional entre el afecto negativo y la dependencia del ejercicio. Mejorar las habilidades de regulación emocional podría prevenir la aparición de la dependencia del ejercicio.(AU)


The copious and uncontrolled practice of exercise can generate psychologicaldependence and mood changes. Emotional regulation and negative affectivity arerelevant processes for the development of addictive patterns. This study analysedthe differences in negative affectivity and emotional regulation based on thepractice profile of exercise; the relationship between exercise dependence,emotional regulation, and negative affectivity; and the mediating role of emotionalregulation in such relationship. 375 endurance sports practitioners participated.The differences in the physical exercise practice profiles were significant in all thestudy variables. Exercise dependence correlated positively and significantly withemotional regulation difficulties and with negative affectivity. Emotional regulationdifficulties were predictors of exercise dependence. There was a mediating effectof emotional regulation difficulties between negative affect and exercisedependence. Improving emotional regulation skills could prevent the onset ofexercise dependence.(AU)


Assuntos
Humanos , Masculino , Feminino , Exercício Físico , Esportes/psicologia , Treinamento de Força , Afeto
10.
BMC Cancer ; 24(1): 493, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637770

RESUMO

BACKGROUND: Muscle mass is important for metastatic prostate cancer survival and quality of life (QoL). The backbone of treatment for men with metastatic castration sensitive prostate cancer (mCSPC) is androgen deprivation therapy (ADT) with an androgen signaling inhibitor. ADT is an effective cancer treatment, but it facilitates significant declines in muscle mass and adverse health outcomes important to mCSPC survivors, such as fatigue, and reductions in physical function, independence, insulin sensitivity, and QoL. In non-metastatic CSPC survivors, resistance training (RT) preserves muscle mass and improves these related health outcomes, but the biggest barrier to RT in CSPC survivors of all stages is fatigue. Creatine monohydrate supplementation coupled with RT (Cr + RT) may address this barrier since creatine plays a critical role in energy metabolism. Cr + RT in cancer-free older adults and other clinical populations improves muscle mass and related health outcomes. Evidence also suggests that creatine supplementation can complement cancer treatment. Thus, Cr + RT is a strategy that addresses gaps in survivorship needs of people with mCSPC. The purpose of this parallel, double-blind randomized controlled trial is to test the effects of 52-weeks of Cr + RT compared with placebo (PLA) and RT (PLA + RT) on muscle mass, other related health outcomes, and markers of cancer progression. METHODS: We will carry out this trial with our team's established, effective, home-based, telehealth RT program in 200 mCSPC survivors receiving ADT, and evaluate outcomes at baseline, 24-, and 52-weeks. RT will occur twice weekly with elastic resistance bands, and an established creatine supplementation protocol will be used for supplementation delivery. Our approach addresses a major facilitator to RT in mCSPC survivors, a home-based RT program, while utilizing a supervised model for safety. DISCUSSION: Findings will improve delivery of comprehensive survivorship care by providing a multicomponent, patient-centered lifestyle strategy to preserve muscle mass, improve health outcomes, and complement cancer treatment (NCT06112990).


Assuntos
Neoplasias da Próstata , Treinamento de Força , Masculino , Humanos , Idoso , Creatina/uso terapêutico , Creatina/farmacologia , Qualidade de Vida , Antagonistas de Androgênios/uso terapêutico , Neoplasias da Próstata/patologia , Androgênios , Força Muscular , Composição Corporal , Processos Neoplásicos , Método Duplo-Cego , Suplementos Nutricionais/efeitos adversos , Músculos/patologia , Poliésteres/farmacologia , Poliésteres/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Sci Rep ; 14(1): 8823, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38627495

RESUMO

The aging process leads to the degeneration of body structure and function. The objective of this study is to conduct a systematic review and meta-analysis of the effects of resistance circuit training (RCT) on comprehensive health indicators of older adults. PubMed, Embase, and Web of Science were searched until August 2023. Primary outcomes were body composition, muscle strength, cardiorespiratory endurance, blood pressure, and functional autonomy. Muscle function and exercise intensity subgroups were analyzed. RCT reduces body fat (MD = - 5.39 kg, 95% CI - 10.48 to - 0.29), BMI (MD = - 1.22, 95% CI - 2.17 to - 0.26), and body weight (MD = - 1.28 kg, 95% CI - 1.78 to - 0.78), and increases lean body mass (MD = 1.42 kg, 95% CI 0.83-2.01) in older adults. It improves upper limb strength (SMD = 2.09, 95% CI 1.7-2.48), lower limb strength (SMD = 2.03, 95% CI 1.56-2.51), cardiorespiratory endurance (MD = 94 m, 95% CI 25.69-162.67), and functional autonomy (MD = - 1.35, 95% CI - 1.73 to - 0.96). High-intensity RCT benefits BMI and body weight, while low-intensity exercise reduces blood pressure. RCT improves muscle function in push, pull, hip, and knee movements in older adults. RCT improves body composition, muscle strength, cardiorespiratory endurance, blood pressure, and functional autonomy in older adults. High-intensity training is superior for body composition, while moderate to low intensity training is more effective for lowering blood pressure.


Assuntos
Exercícios em Circuitos , Treinamento de Força , Humanos , Idoso , Exercício Físico , Força Muscular , Peso Corporal
12.
Sci Rep ; 14(1): 8388, 2024 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600177

RESUMO

MicroRNAs (miRNAs) may play a crucial regulatory role in the process of muscle atrophy induced by high-altitude hypoxia and its amelioration through resistance training. However, research in this aspect is still lacking. Therefore, this study aimed to employ miRNA microarray analysis to investigate the expression profile of miRNAs in skeletal muscle from an animal model of hypoxia-induced muscle atrophy and resistance training aimed at mitigating muscle atrophy. The study utilized a simulated hypoxic environment (oxygen concentration at 11.2%) to induce muscle atrophy and established a rat model of resistance training using ladder climbing, with a total intervention period of 4 weeks. The miRNA expression profile revealed 9 differentially expressed miRNAs influenced by hypoxia (e.g., miR-341, miR-32-5p, miR-465-5p) and 14 differentially expressed miRNAs influenced by resistance training under hypoxic conditions (e.g., miR-338-5p, miR-203a-3p, miR-92b-3p) (∣log2(FC)∣ ≥ 1.5, p < 0.05). The differentially expressed miRNAs were found to target genes involved in muscle protein synthesis and degradation (such as Utrn, mdm2, eIF4E), biological processes (such as negative regulation of transcription from RNA polymerase II promoter, regulation of transcription, DNA-dependent), and signaling pathways (such as Wnt signaling pathway, MAPK signaling pathway, ubiquitin-mediated proteolysis, mTOR signaling pathway). This study provides a foundation for understanding and further exploring the molecular mechanisms underlying hypoxia-induced rats muscle atrophy and the mitigation of atrophy through resistance training.


Assuntos
MicroRNAs , Treinamento de Força , Humanos , Ratos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Hipóxia/genética , Hipóxia/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/genética , Atrofia Muscular/metabolismo , Perfilação da Expressão Gênica
13.
PLoS One ; 19(4): e0299481, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625975

RESUMO

INTRODUCTION: Exercise produces an immediate lessening of pain sensitivity (Exercise-Induced Hypoalgesia (EIH)) in healthy individuals at local and distant sites, possibly through a shared mechanism with conditioned pain modulation (CPM). Dynamic resistance exercise is a recommended type of exercise to reduce pain, yet limited research has examined the effects of intensity on EIH during this type of exercise. Therefore, the primary purpose of this study is to compare changes in PPT at a local and distant site during a leg extension exercise at a high intensity, a low intensity, or a quiet rest condition. A secondary purpose is to examine if CPM changes after each intervention. The final purpose is to examine if baseline pain sensitivity measures are correlated with response to each intervention. METHODS: In a randomized controlled trial of 60 healthy participants, participants completed baseline pain sensitivity testing (heat pain threshold, temporal summation, a cold pressor test as measure of CPM) and were randomly assigned to complete a knee extension exercise at: 1) high intensity (75% of a 1 Repetition Maximum (RM), 2) low intensity (30% 1RM), or 3) Quiet Rest. PPT was measured between each set at a local (quadriceps) and distant (trapezius) site during the intervention. CPM was then repeated after the intervention. To test the first purpose of the study, a three-way ANOVA examined for time x site x intervention interaction effects. To examine for changes in CPM by group, a mixed-model ANOVA was performed. Finally, a Pearson Correlation examined the association between baseline pain sensitivity and response to each intervention. RESULTS: Time x site x intervention interaction effects were not significant (F(5.3, 150.97) = 0.87, p = 0.51, partial eta2 = 0.03). CPM did not significantly change after the interventions (time x intervention F(1,38) = 0.81, p = 0.37, partial eta2 = 0.02. EIH effects at the quadriceps displayed a significant, positive moderate association with baseline HPT applied over the trapezius (r = 0.61, p<0.01) and TS (r = 0.46, p = 0.04). DISCUSSION: In healthy participants, PPT and CPM did not significantly differ after a leg extension exercise performed at a high intensity, low intensity, or quiet rest condition. It is possible pre-intervention CPM testing with a noxious stimuli may have impaired inhibitory effects frequently observed during exercise but future research would need to examine this hypothesis.


Assuntos
Treinamento de Força , Humanos , Medição da Dor , Percepção da Dor/fisiologia , Dor , Limiar da Dor/fisiologia
14.
Scand J Med Sci Sports ; 34(3): e14608, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38515303

RESUMO

PURPOSE: The aim of this study was to determine whether a 9-week resistance training program based on high load (HL) versus low load combined with blood flow restriction (LL-BFR) induced a similar (i) distribution of muscle hypertrophy among hamstring heads (semimembranosus, SM; semitendinosus, ST; and biceps femoris long head, BF) and (ii) magnitude of tendon hypertrophy of ST, using a parallel randomized controlled trial. METHODS: A total of 45 participants were randomly allocated to one of three groups: HL, LL-BFR, and control (CON). Both HL and LL-BFR performed a 9-week resistance training program composed of seated leg curl and stiff-leg deadlift exercises. Freehand 3D ultrasound was used to assess the changes in muscle and tendon volume. RESULTS: The increase in ST volume was greater in HL (26.5 ± 25.5%) compared to CON (p = 0.004). No difference was found between CON and LL-BFR for the ST muscle volume (p = 0.627). The change in SM muscle volume was greater for LL-BFR (21.6 ± 27.8%) compared to CON (p = 0.025). No difference was found between HL and CON for the SM muscle volume (p = 0.178).There was no change in BF muscle volume in LL-BFR (14.0 ± 16.5%; p = 0.436) compared to CON group. No difference was found between HL and CON for the BF muscle volume (p = 1.0). Regarding ST tendon volume, we did not report an effect of training regimens (p = 0.411). CONCLUSION: These results provide evidence that the HL program induced a selective hypertrophy of the ST while LL-BFR induced hypertrophy of SM. The magnitude of the selective hypertrophy observed within each group varied greatly between individuals. This finding suggests that it is very difficult to early determine the location of the hypertrophy among a muscle group.


Assuntos
Músculos Isquiossurais , Treinamento de Força , Humanos , Músculos Isquiossurais/diagnóstico por imagem , Força Muscular/fisiologia , Hipertrofia , Tendões , Treinamento de Força/métodos , Fluxo Sanguíneo Regional/fisiologia , Músculo Esquelético/fisiologia
15.
PeerJ ; 12: e17008, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464757

RESUMO

This study aimed to compare the mechanical (lifting velocity and maximum number of repetitions), physiological (muscular activation, lactate, heart rate, and blood pressure), and psychological (rating of perceived exertion) responses to upper-body pushing exercises performed wearing a sports elastomeric garment or a placebo garment. Nineteen physically active young adults randomly completed two training sessions that differed only in the sports garment used (elastomeric technology or placebo). In each session, subjects performed one set of seated shoulder presses and another set of push-ups until muscular failure. The dependent variables were measured immediately after finishing the set of each exercise. Compared to the placebo garment, the elastomeric garment allowed participants to obtain greater muscular activation in the pectoralis major (push-ups: p = 0.04, d = 0.49; seated shoulder press: p < 0.01, d = 0.64), triceps brachialis (push-ups, p < 0.01, d = 0.77; seated shoulder press: p < 0.01, d = 0.65), and anterior deltoid (push-ups: p < 0.01, d = 0.72; seated shoulder press: p < 0.01, d = 0.83) muscles. Similarly, participants performed more repetitions (push-ups: p < 0.01; d = 0.94; seated shoulder press: p = 0.03, d = 0.23), with higher movement velocity (all p ≤ 0.04, all d ≥ 0.47), and lower perceived exertion in the first repetition (push-ups: p < 0.01, d = 0.61; seated shoulder press: p = 0.05; d = 0.76) wearing the elastomeric garment compared to placebo. There were no between-garment differences in most cardiovascular variables (all p ≥ 0.10). Higher diastolic blood pressure was only found after the seated shoulder press wearing the elastomeric garment compared to the placebo (p = 0.04; d = 0.49). Finally, significantly lower blood lactate levels were achieved in the push-ups performed wearing the elastomeric garment (p < 0.01; d = 0.91), but no significant differences were observed in the seated shoulder press (p = 0.08). Overall, the findings of this study suggest that elastomeric technology integrated into a sports garment provides an ergogenic effect on mechanical, physiological, and psychological variables during the execution of pushing upper-limb resistance exercises.


Assuntos
Treinamento de Força , Adulto Jovem , Humanos , Ombro/fisiologia , Levantamento de Peso/fisiologia , Lactatos , Vestuário
16.
Sensors (Basel) ; 24(6)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38544173

RESUMO

Incorrect limb position while lifting heavy weights might compromise athlete success during weightlifting performance, similar to the way that it increases the risk of muscle injuries during resistance exercises, regardless of the individual's level of experience. However, practitioners might not have the necessary background knowledge for self-supervision of limb position and adjustment of the lifting position when improper movement occurs. Therefore, the computerized analysis of movement patterns might assist people in detecting changes in limb position during exercises with different loads or enhance the analysis of an observer with expertise in weightlifting exercises. In this study, hidden Markov models (HMMs) were employed to automate the detection of joint position and barbell trajectory during back squat exercises. Ten volunteers performed three lift movements each with a 0, 50, and 75% load based on body weight. A smartphone was used to record the movements in the sagittal plane, providing information for the analysis of variance and identifying significant position changes by video analysis (p < 0.05). Data from individuals performing the same movements with no added weight load were used to train the HMMs to identify changes in the pattern. A comparison of HMMs and human experts revealed between 40% and 90% agreement, indicating the reliability of HMMs for identifying changes in the control of movements with added weight load. In addition, the results highlighted that HMMs can detect changes imperceptible to the human visual analysis.


Assuntos
Treinamento de Força , Humanos , Reprodutibilidade dos Testes , Treinamento de Força/métodos , Levantamento de Peso/fisiologia , Postura , Extremidades , Movimento
17.
Sensors (Basel) ; 24(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38544213

RESUMO

Movement control can be an indicator of how challenging a task is for the athlete, and can provide useful information to improve training efficiency and prevent injuries. This study was carried out to determine whether inertial measurement units (IMU) can provide reliable information on motion variability during strength exercises, focusing on the squat. Sixty-six healthy, strength-trained young adults completed a two-day protocol, where the variability in the squat movement was analyzed at two different loads (30% and 70% of one repetition maximum) using inertial measurement units and a force platform. The time series from IMUs and force platforms were analyzed using linear (standard deviation) and non-linear (detrended fluctuation analysis, sample entropy and fuzzy entropy) measures. Reliability was analyzed for both IMU and force platform using the intraclass correlation coefficient and the standard error of measurement. Standard deviation, detrended fluctuation analysis, sample entropy, and fuzzy entropy from the IMUs time series showed moderate to good reliability values (ICC: 0.50-0.85) and an acceptable error. The study concludes that IMUs are reliable tools for analyzing movement variability in strength exercises, providing accessible options for performance monitoring and training optimization. These findings have implications for the design of more effective strength training programs, emphasizing the importance of movement control in enhancing athletic performance and reducing injury risks.


Assuntos
Treinamento de Força , Adulto Jovem , Humanos , Treinamento de Força/métodos , Reprodutibilidade dos Testes , Fenômenos Biomecânicos , Postura , Exercício Físico
18.
PLoS One ; 19(3): e0301037, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547208

RESUMO

BACKGROUND: The favorable health-promoting adaptations to exercise result from cumulative responses to individual bouts of physical activity. Older adults often exhibit anabolic resistance; a phenomenon whereby the anabolic responses to exercise and nutrition are attenuated in skeletal muscle. The mechanisms contributing to age-related anabolic resistance are emerging, but our understanding of how chronological age influences responsiveness to exercise is incomplete. The objective was to determine the effects of healthy aging on peripheral blood metabolomic response to a single bout of resistance exercise and whether any metabolites in circulation are predictive of anabolic response in skeletal muscle. METHODS: Thirty young (20-35 years) and 49 older (65-85 years) men and women were studied in a cross-sectional manner. Participants completed a single bout of resistance exercise consisting of eight sets of 10 repetitions of unilateral knee extension at 70% of one-repetition maximum. Blood samples were collected before exercise, immediately post exercise, and 30-, 90-, and 180-minutes into recovery. Proton nuclear magnetic resonance spectroscopy was used to profile circulating metabolites at all timepoints. Serial muscle biopsies were collected for measuring muscle protein synthesis rates. RESULTS: Our analysis revealed that one bout of resistance exercise elicits significant changes in 26 of 33 measured plasma metabolites, reflecting alterations in several biological processes. Furthermore, 12 metabolites demonstrated significant interactions between exercise and age, including organic acids, amino acids, ketones, and keto-acids, which exhibited distinct responses to exercise in young and older adults. Pre-exercise histidine and sarcosine were negatively associated with muscle protein synthesis, as was the pre/post-exercise fold change in plasma histidine. CONCLUSIONS: This study demonstrates that while many exercise-responsive metabolites change similarly in young and older adults, several demonstrate age-dependent changes even in the absence of evidence of sarcopenia or frailty. TRIAL REGISTRATION: Clinical trial registry: ClinicalTrials.gov NCT03350906.


Assuntos
Treinamento de Força , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Estudos Transversais , Histidina/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/fisiologia , Espectroscopia de Prótons por Ressonância Magnética , Adulto Jovem , Adulto
19.
Nutrition ; 122: 112389, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38428220

RESUMO

PURPOSE: Nutrient timing is a concept that emphasizes the intentional ingestion of whole or fortified foods, and dietary supplements, to adequately fuel for, and recover from, acute and chronic exercise. The nutrition strategies used by powerlifters around training sessions have not, to our knowledge, been previously investigated. This study explored the self-reported periworkout (before, during, and after) nutrition practices of competitive powerlifters, including what, why, and information source that informed practice, with comparison to current sport nutrition guidelines. METHODS: Actively competing male (n = 240) and female (n = 65) powerlifters completed a cross-sectional online survey of self-reported periworkout nutrition practices in the pre-, intra-, and postexercise periods, fasted training, and supplementation. Data are presented as the number (n) and percentage (%) of all powerlifters practicing a given strategy followed by a % of responses reporting various practices or beliefs within this strategy. Categorical subgroups (sex, age, and weight class; and competitive caliber) were analyzed with a chi-square test or Fisher's exact test and denoted where significant (P ≤ 0.05). RESULTS: Most powerlifters reported paying specific attention to nutrition practices in the pre-exercise period (n = 261; 85.6%) by ingesting more carbohydrate (CHO) rich foods (n = 234; 89.6%) for the purpose of assisting in training performance (n = 222; 85.1%). Most powerlifters reported intraexercise nutrition strategies (n = 211; 69.2%), of which most included ingesting more CHO rich foods (n = 159; 74.5%) for the purpose of feeling less hungry and/or boosting energy levels during training (n = 129; 61.1%). Most powerlifters reported paying attention to postexercise nutrition (n = 244; 80%), by ingesting more protein rich foods (n = 182; 74.6%) for the purpose of recovering better for the whole day (n = 152; 62.3%) and enhancing the benefits of training (n = 149; 61.1%). Most powerlifters did not complete training sessions in the fasted state (n = 262; 85.9%). Most powerlifters reported paying attention to supplementation before training (n = 237; 77.7%), of which preworkout formulas (n = 137; 57.8%), energy drinks (n = 101; 42.6%), creatine (n = 88; 37.1%), and caffeine pills (n = 70; 29.5%) were most reported. Supplementation was used to assist in training performance (n = 197; 83.1%) and increase wakefulness/alertness (n = 183; 77.2%). Males reported more often than females that they informed multiple elements of their nutrition practices with the information they read or watched somewhere (P = 0.002-0.012). CONCLUSION: The periworkout nutrition practices used by competitive powerlifters followed current sport nutrition guidelines, by using CHO sources to fuel for training and ensuring the provision of protein postexercise. Competitive powerlifters may wish to exert caution with supplementation, as there is a risk of harm or inadvertent doping.


Assuntos
Treinamento de Força , Humanos , Masculino , Feminino , Estudos Transversais , Exercício Físico , Suplementos Nutricionais , Estado Nutricional
20.
BMC Public Health ; 24(1): 798, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481173

RESUMO

BACKGROUND: The COVID-19 pandemic has had a significant impact on individual health and fitness routines globally. Resistance training, in particular, has become increasingly popular among men and women looking to maintain or improve their physical fitness during the pandemic. However, using Anabolic Steroids (AS) for performance enhancement in resistance training has known adverse effects. Thus, this study aimed to explore the prevalence of AS use among men and women resistance training practitioners after the COVID-19 pandemic. METHODS: A cross-sectional survey was conducted among 3,603 resistance training practitioners (1,855 men and 1,748 women) in various geographical locations impacted by COVID-19. The participants were asked to complete self-administered questionnaires, which included questions regarding demographic information, training habits, and current or prior usage of AS. The data were analyzed using SPSS statistical software and the chi-square method, with a significance level of (P < 0.05). RESULTS: A total of 3603 men and women resistance training practitioners completed the survey. In the study, 53.05% of men and 41.99% of women used anabolic and androgenic steroids. Of those men who used steroids, 29.47% used Testosterone, while 31.20% of women used Winstrol. Additionally, 50.30% of men used steroids via injection, while 49.05% of women used them orally. According to the study, 49.99% of the participants had 6 to 12 months of experience with resistance training, and 64.25% of them underwent three training sessions per week. The analysis using the χ2 test did not reveal any significant difference between men and women in terms of duration of bodybuilding, frequency per week, and engagement in other activities. CONCLUSION: This study shows that a significant proportion of men and women resistance training practitioners used AS, particularly among young adults with limited training experience. Thus, there is a need for targeted education and awareness campaigns to address the hazards of AS use and promote healthy training habits during the COVID-19 pandemic.


Assuntos
Anabolizantes , COVID-19 , Treinamento de Força , Masculino , Adulto Jovem , Humanos , Feminino , Esteróides Androgênicos Anabolizantes , Pandemias , Treinamento de Força/métodos , Prevalência , Estudos Transversais , Anabolizantes/uso terapêutico , Congêneres da Testosterona , Esteroides
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