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1.
Eur J Appl Physiol ; 123(6): 1311-1321, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36802029

RESUMO

PURPOSE: This study evaluated the concurrent training (CT) effect in combination with either progressive energy restriction (PER) or severe energy restriction (SER) on body composition and strength-related variables in resistance-trained women. METHODS: Fourteen women (29.5 ± 3.8 years; 23.8 ± 2.8 kg·m-2) were randomly assigned to a PER (n = 7) or SER (n = 7) group. Participants performed an 8-week CT program. Pre- and post-intervention measures of fat mass (FM) and fat-free mass (FFM) were assessed by dual-energy X-ray absorptiometry and strength-related variables were assessed through 1-repetition maximum (in the squat and bench press) and countermovement jump. RESULTS: Significant reductions in FM were observed in PER and SER (Δ = - 1.7 ± 0.4 kg; P = < 0.001; ES = - 0.39 and Δ = - 1.2 ± 0.6 kg; P = 0.002; ES = - 0.20, respectively). After correcting FFM for fat-free adipose tissue (FFAT), no significant differences for this variable were found either in PER (Δ = - 0.3 ± 0.1; P = 0.071; ES = - 0.06) or in SER (Δ = - 0.2 ± 0.1; P = 0.578; ES = - 0.04). There were no significant changes in the strength-related variables. No between-group differences were found in any of the variables. CONCLUSION: A PER has similar effects to a SER on body composition and strength in resistance-trained women performing a CT program. Given that PER is more flexible and thus may enhance dietary adherence, it might be a better alternative for FM reduction compared to SER.


Assuntos
Treinamento Resistido , Feminino , Humanos , Absorciometria de Fóton , Tecido Adiposo , Composição Corporal , Dieta , Força Muscular
2.
Medicina (Kaunas) ; 58(7)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35888560

RESUMO

Background and Objectives: To determine the most commonly used patient-reported outcome measures (PROMs) in exercise-induced leg pain (EILP) and to identify specific PROMs for EILP in order to evaluate their psychometric properties and methodological quality. Materials and Methods: A strategic search was performed in different databases to identify and extract the characteristics of studies based on the use of PROMs in patients with EILP. Specific PROMs were evaluated according to the Terwee et al. and COSMIN criteria. Results: Fifty-six studies were included in the review. The Medial Tibial Stress Syndrome Score (MTSSS), Lower Extremity Functional Scale (LEFS) and Exercise-Induced Leg Pain Questionnaire (EILP-Q) were identified as specific PROMs for EILP. The Visual Analog Scale (VAS) was the most widely used instrument in the assessment of EILP. The methodological quality assessment showed six positive values for the LEFS, four for the MTSSS and three for the EILP-Q for the eight psychometric properties analyzed according to the COSMIN criteria. The evaluation of the nine psychometric properties according to Terwee showed five positive values for the LEFS and MTSSS, and three for the EILP-Q. Conclusions: The overall methodological quality of the PROMs used was low. The VAS was the most widely used instrument in the assessment of EILP, and the LEFS was the highest quality PROM available for EILP, followed by the MTSSS and EILP-Q, respectively.


Assuntos
Exercício Físico , Perna (Membro) , Dor , Medidas de Resultados Relatados pelo Paciente , Exercício Físico/efeitos adversos , Humanos , Perna (Membro)/fisiopatologia , Dor/etiologia , Psicometria , Qualidade de Vida , Inquéritos e Questionários
3.
J Pediatr Gastroenterol Nutr ; 72(1): 127-134, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32804905

RESUMO

OBJECTIVES: The aim of this study was to analyze effects of a 12-month lifestyle modification that involved a Mediterranean diet (MedDiet) and physical activity (PA) program in a population of metabolically healthy obese children (MHOCh). METHODS: We included a population of MHOCh with ≤1 of the following criteria: waist circumference and blood pressure ≥90 percentile, triglycerides >150 mg/dL, high-density lipoprotein-cholesterol (HDL-c) <40 mg/dL, or impaired fasting glucose. After 12 months of intensive lifestyle modification, anthropometric measurements, glycemic and lipid profiles, adherence to the MedDiet, energy intake, PA, body composition, and carotid intima-media thickness (cIMT) were analyzed. RESULTS: One hundred thirty-one MHOCh (70 boys and 61 girls; P = 0.65, age: 7.9 ±â€Š1.3 years, body mass index [BMI]: 24.7 ±â€Š3.5 kg/m2) were included. After 12 months of intervention, a significant decrease in standard deviation (SD) units of body weight (-0.5 ±â€Š0.1; P < 0.001) and BMI (-0.5 ±â€Š0.1; P < 0.001) were observed in the total population. A significant improvement in adherence to the MedDiet (+2 points) and a significant reduction in protein, fatty acids, total fat, and cholesterol intake in the entire population were observed. All participants did more moderate-vigorous PA, which led to a significant increase in lean and total mass and decrease in total fat. Significant improvements in the glycemic profile (insulin levels [-6.6 µIU/mL, P < 0.001] and HOMA index [-1.2, P < 0.001]) were observed. Participants with pathological cIMT values reduced this cardiovascular predictor to normal values. CONCLUSIONS: A 12-month lifestyle modification intervention involving weight loss with MedDiet and PA in MHOCh yielded improvements in MedDiet adherence, lipid intake, moderate-vigorous PA, body composition, insulin resistance, and cIMT.


Assuntos
Espessura Intima-Media Carotídea , Resistência à Insulina , Índice de Massa Corporal , Criança , Feminino , Humanos , Estilo de Vida , Masculino , Obesidade , Fatores de Risco
4.
Eur J Appl Physiol ; 121(8): 2349-2359, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34003364

RESUMO

PURPOSE: The aim of this study was to evaluate the effect of a ketogenic diet on blood pressure, visceral adipose tissue (VAT), bone mineral content (BMC), and bone mineral density (BMD) in trained women. METHODS: Twenty-one resistance-trained women performed an 8-week resistance training program after a 3-week familiarization phase. Participants were randomly assigned to a non-ketogenic diet (n = 11, NKD) or ketogenic diet (n = 10, KD) group. Health parameters were measured before and after the nutritional intervention. Blood pressure was measured using a digital automatic monitor, while VAT, BMC, and BMD changes were measured by dual-energy X-ray absorptiometry. RESULTS: There was a significant reduction in systolic blood pressure in KD (mean ± SD [IC 95%], P value, Hedges' g; - 6.3 ± 6.0 [- 10.5, - 2.0] mmHg, P = 0.009, g = - 0.81) but not in NKD (- 0.4 ± 8.9 [- 6.8, 6.0] mmHg, P = 0.890, g = - 0.04). The results on VAT showed no changes in both groups. The KD showed a small favorable effect on BMD (0.02 ± 0.02 [0.01, 0.03] g·cm-2, P = 0.014, g = 0.19) while NKD did not show significant changes (0.00 ± 0.02 [- 0.02, 0.02] g·cm-2, P = 0.886, g = 0.01). No differences in group or in the time × group interaction were found in any of the variables. CONCLUSIONS: Consuming a low-carbohydrate high-fat KD in conjunction with a resistance training program might help to promote the improvement of health-related markers in resistance-trained women. Long-term studies are required to evaluate the superiority of a KD in comparison to a traditional diet.


Assuntos
Dieta com Restrição de Carboidratos , Dieta Cetogênica , Treinamento Resistido , Adulto , Pressão Sanguínea/fisiologia , Densidade Óssea/fisiologia , Ingestão de Energia , Feminino , Humanos , Gordura Intra-Abdominal/fisiologia
5.
Biol Sport ; 37(4): 325-331, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33343065

RESUMO

The objective of this research was to compare the effect of Post-Activation Performance Enhancement (PAPE) exerted on the back squat (BS) versus the barbell hip thrust (HT) on the sprint performance (5- and 10-m). 17 male amateur rugby players participated in the study (age 22.14 ± 2.52 years; body mass 81.06 ± 9.6 kg; height 1.78 ± 0.05 m). All participants performed a dynamic maximum strength test (3RM) in BS and HT at maximum speed. Two randomized sessions were performed inducing PAPE using BS or HT trough three series with three repetitions at 85% 1RM eight minutes before the sprint tests. An ANOVA of repeated measurement, found no differences in the time for 5-m (F = 0.398, P = 0.537, η2p = 0.024) or 10-m (F = 2.589, P = 0.127, η2p = 0.139). There were no significant differences in the Protocol effect between HT and BS in 5-m or 10-m (F = 2.963, P = 0.104, η2p = 0.156 and F = 1.472, P = 0.243 η2p = 0.084, respectively). There were also no differences in the Time x Protocol interaction at 5-m (F = 0.001, P = 0.976, η2p < 0.001) or 10-m (F = 4.174, P = 0.058, η2p = 0.207). The effect size obtained in the results of the sprint tests was small in both exercises (ES < 0.2). None of the BS or HT exercises performed with heavy load induced a significant PAPE phenomenon on the ability to sprint in rugby players.

6.
Eur J Appl Physiol ; 119(4): 933-940, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30680448

RESUMO

PURPOSE: The aim of this study was to compare the effects of resistance training (RT) with an emphasis on either muscular strength-type RT or muscular endurance-type RT on measures of body composition. METHODS: Twenty-five resistance-trained men (age 28.4 ± 6.4 years; body mass 75.9 ± 8.4 kg; height 176.9 ± 7.5 cm) were randomly assigned to either a strength-type RT group that performed three sets of 6-8 repetition maximum (RM) with 3-min rest (n = 10), an endurance-type RT group that performed three sets of 20-25 RM with a 60-s rest interval (n = 10), or a control group (n = 5, CG). All groups completed each set until muscular failure and were supervised to follow a hyperenergetic diet (39 kcal·kg-1·day-1). Body composition changes were measured by dual-energy X-ray absorptiometry. RESULTS: After 8 weeks, we found significant increases in total body mass (0.9 [0.3-1.5] kg; p < 0.05; ES = < 0.2) and lean body mass (LBM) (1.3 [0.5-2.2] kg; p < 0.05; ES = 0.31) only in the strength-type RT group; however, no significant interactions were noted between groups. CONCLUSIONS: Although only strength-type RT showed statistically significant increases in LBM from baseline, no between-group differences were noted for any body composition outcome. These findings suggest that LBM gains in resistance trained are not significantly influenced by the type of training stimulus over an 8-week training period.


Assuntos
Composição Corporal/fisiologia , Força Muscular/fisiologia , Resistência Física/fisiologia , Treinamento Resistido , Absorciometria de Fóton/métodos , Adaptação Fisiológica/fisiologia , Adulto , Índice de Massa Corporal , Humanos , Masculino , Músculo Esquelético/fisiologia
7.
Int J Sports Med ; 40(13): 842-849, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491790

RESUMO

The purpose was to analyze the influence of oral contraceptive use on body composition and strength levels in trained women. Twenty-three resistance-trained women participated in this study (age=27.4±3.4 years; fat mass=28.0±5.0%; BMI=22.9±2.7 kg∙m-2). Subjects performed an 8-week non-linear resistance-training program. Participants were assigned to either a group that consumed oral contraceptives (n=12, OC) or to a group that did not consume (n=11, NOC). Changes in body composition were measured by dual energy X-ray absorptiometry. Strength performance was assessed via the one maximum repetition (1RM) test in the squat and bench press, and muscular power was evaluated using the countermovement jump (CMJ) test. Fat free mass increased significantly in OC but no changes were seen in NOC. There were no changes in fat mass for either OC or NOC. Significant changes were found in bench press 1RM for both OC and NOC; similarly, increases in squat 1RM were reported in OC and NOC. Alternatively, no significant changes were found in CMJ in both OC and NOC. No significant between-group differences were detected in any of the studied variables. The use of oral contraceptives during resistance training did not negatively affect body composition or strength levels in trained women.


Assuntos
Composição Corporal/efeitos dos fármacos , Anticoncepcionais Orais/farmacologia , Força Muscular/efeitos dos fármacos , Treinamento Resistido , Adaptação Fisiológica , Adulto , Índice de Massa Corporal , Dieta , Teste de Esforço/métodos , Feminino , Humanos , Exercício Pliométrico , Adulto Jovem
8.
Curr Obes Rep ; 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703299

RESUMO

PURPOSE OF REVIEW: The present study aims to review the existing literature to identify pathophysiological proteins in obesity by conducting a systematic review of proteomics studies. Proteomics may reveal the mechanisms of obesity development and clarify the links between obesity and related diseases, improving our comprehension of obesity and its clinical implications. RECENT FINDINGS: Most of the molecular events implicated in obesity development remain incomplete. Proteomics stands as a powerful tool for elucidating the intricate interactions among proteins in the context of obesity. This methodology has the potential to identify proteins involved in pathological processes and to evaluate changes in protein abundance during obesity development, contributing to the identification of early disease predisposition, monitoring the effectiveness of interventions and improving disease management overall. Despite many non-targeted proteomic studies exploring obesity, a comprehensive and up-to-date systematic review of the molecular events implicated in obesity development is lacking. The lack of such a review presents a significant challenge for researchers trying to interpret the existing literature. This systematic review was conducted following the PRISMA guidelines and included sixteen human proteomic studies, each of which delineated proteins exhibiting significant alterations in obesity. A total of 41 proteins were reported to be altered in obesity by at least two or more studies. These proteins were involved in metabolic pathways, oxidative stress responses, inflammatory processes, protein folding, coagulation, as well as structure/cytoskeleton. Many of the identified proteomic biomarkers of obesity have also been reported to be dysregulated in obesity-related disease. Among them, seven proteins, which belong to metabolic pathways (aldehyde dehydrogenase and apolipoprotein A1), the chaperone family (albumin, heat shock protein beta 1, protein disulfide-isomerase A3) and oxidative stress and inflammation proteins (catalase and complement C3), could potentially serve as biomarkers for the progression of obesity and the development of comorbidities, contributing to personalized medicine in the field of obesity. Our systematic review in proteomics represents a substantial step forward in unravelling the complexities of protein alterations associated with obesity. It provides valuable insights into the pathophysiological mechanisms underlying obesity, thereby opening avenues for the discovery of potential biomarkers and the development of personalized medicine in obesity.

9.
Sports Health ; : 19417381241253267, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38800872

RESUMO

BACKGROUND: The aim of this research was to evaluate the impact of a nonlinear training program on visceral adipose tissue (VAT) and systolic (SBP) and diastolic (DBP) blood pressure, as well as the response of biochemical parameters such as fasting plasma glucose (FPG), total cholesterol (TC), high-density cholesterol (HDL-C), low-density cholesterol (LDL-C), and triglycerides (TG). HYPOTHESIS: The nonlinear periodized program would produce greater improvements in outcomes than the linear periodized training program. STUDY DESIGN: Randomized cross-sectional design. LEVEL OF EVIDENCE: Level 3. METHODS: Older adults with no previous training experience (10 male and 8 female [age, 64 ± 2.1 years; height, 165.12 ± 7.5 cm; body mass, 72.5 ± 11.4 kg; body max index, 26.5 ± 3.2 kg/m2]) were randomized to linear (n = 9, TT) or undulating (n = 9, UT) periodization. After a 3-week familiarization period, all participants performed 3 sessions of resistance training per week; 8 weeks of training were conducted for each group. Dual x-ray absorptiometry was used to measure VAT, and SBP and DBP were measured using an OMRON M3 digital automatic blood pressure monitor. Blood samples were collected between 8:00 a.m. and 9:30 a.m. after 12-hour overnight fasting. RESULTS: Both interventions significantly (P < 0.05) decreased FPG, TC, LDL-C, and TG. A significant decrease in SBP and DBP was observed only in the UT group (P < 0.05). No significant between-group differences in outcomes were observed (P > 0.5). However, the effect size was marginally more pronounced for all outcomes in the UT group. CONCLUSION: An undulating periodization program was effective in improving VAT, TC, LDL-C, FPG, HDL-C, TG, and blood glucose levels in older adults. CLINICAL RELEVANCE: Resistance training can be programmed in an undulating or traditional way in older adults based on improvements in health parameters, considering adherence and individual preferences.

10.
J Int Soc Sports Nutr ; 21(1): 2306308, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38285913

RESUMO

BACKGROUND: The effect of low-carbohydrate high-fat dietary manipulation, such as the ketogenic diet (KD), on muscle strength assessment in resistance-training (RT) participants has focused on the one-repetition maximum test (1-RM). However, a pre-specified 1-RM value during an exercise training program disregards several confounding factors (i.e. sleep, diet, and training-induced fatigue) that affect the exerciser's "true" load and daily preparedness. We aimed to evaluate the effect of a 6-week RT program on load control-related variables in trained subjects following a KD intervention. METHODS: Fourteen resistance-trained individuals (3F, 11 M; 30.1 [6.2] years; 174.2 [7.6] cm; 75.7 [10.8] kg; BMI 24.8 [2.1] kg·m-2) completed this single-arm repeated-measures clinical trial. Load management variables included volume load, number of repetitions, perceived exertion (RPE), movement velocity loss, and exertion index. These primary outcomes were assessed weekly before, during, and at the end of a 6-week RT program that included traditional RT exercises (bench press, femoral lying down, lat pulldown, leg extension, and back squat). RESULTS: There was a significant difference in RPE between weeks (p = 0.015, W = 0.19) with a slight trend in decreasing RPE. We found differences in the volume load per week (p < 0.001; W = 0.73 and p < 0.001, W = 0.81, respectively), with an increase in the last weeks. In the control of the load based on movement velocity, we did not find significant differences between weeks (p = 0.591, W = 0.06), although significant differences were found in the effort index (p = 0.026, W = 0.17). CONCLUSIONS: A KD diet in recreational strength participants does not appear to lead to performance losses during a RT program aimed at improving body composition. However, the lack of adherence and familiarity with the ketogenic diet must be considered specially during first weeks.


Assuntos
Dieta Cetogênica , Treinamento Resistido , Humanos , Composição Corporal , Exercício Físico/fisiologia , Força Muscular , Músculo Esquelético
11.
J Sports Sci ; 31(16): 1741-52, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23869701

RESUMO

The International Physical Activity Questionnaire (IPAQ) has been widely used to assess physical activity in healthy populations. The present study compared physical activity assessed by the long, self-administrated version of the International Physical Activity Questionnaire with physical activity assessed by accelerometry in patients with fibromyalgia. A total of 99 (five men) participants with fibromyalgia completed the International Physical Activity Questionnaire and wore an accelerometer for nine consecutive days. We analysed the correlations of physical activity expressed as min · day(-1) of light, moderate, vigorous, and moderate to vigorous (MVPA) intensity, as well as time spent sitting, by the International Physical Activity Questionnaire and accelerometry by Spearman correlations. Bland and Altman plots were performed to verify the agreements between both instruments. The results showed weak yet significant correlations (Rs = 0.15-0.39, all P < 0.05) in all physical activity intensities between the two instruments, except for sedentary time. The highest correlations were observed for physical activity at home or in garden (Rs = 0.297, P < 0.01). The results suggest that the long self-administrated International Physical Activity Questionnaire is a questionable instrument to assess physical activity in patients with fibromyalgia. Therefore, physical activity measurement in fibromyalgia patients should not be limited solely to self-reported measures.


Assuntos
Acelerometria , Exercício Físico , Fibromialgia , Autorrelato , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Adulto Jovem
12.
PeerJ Comput Sci ; 9: e1310, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346711

RESUMO

In recent years, different tools have been introduced into the educational landscape to promote active participation and interaction between students and teachers through personal response systems. The evolution of this methodology has allowed students to participate in real-time by answering questions posed. Previous reviews on the effectiveness of real-time classroom interactive competition (RCIC) on academic performance have been performed; however, this research was based only on Kahoot, without considering other RCIC tools or programs. In addition, the RCIC effectiveness at different educational levels and its effect according to the duration of the intervention has not been meta-analytically analyzed until to date. The aim of this meta-analysis was to analyze the RCIC effectiveness in improving academic performance. A search focused on studies from the educational field published from 2010 until September 2022 was performed. Experimental studies with objective and valid data (scores based on tests or exams) were included. From a total of 397 studies considered potentially eligible, 23 studies met the inclusion criteria. The sample was n = 1,877 for the experimental group and n = 1,765 for the control group with an academic improvement in favor to experimental group (MD 7.34; CI [5.31-9.43]; p < 0.001). There was also significant improvement in academic performance when analyzing different educational levels and different tools. In addition, both short-term interventions (two weeks or less in duration) and long-term (from two weeks to one year in duration) were effective. Therefore, RCIC interventions seem to be an effective strategy to improve academic performance.

13.
Obes Rev ; 24(10): e13599, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37416977

RESUMO

The increasing prevalence of metabolic syndrome is associated with major health and socioeconomic consequences. Currently, physical exercise, together with dietary interventions, is the mainstay of the treatment of obesity and related metabolic complications. Although exercise training includes different modalities, with variable intensity, duration, volume, or frequency, which may have a distinct impact on several characteristics related to metabolic syndrome, the potential effects of exercise timing on metabolic health are yet to be fully elucidated. Remarkably, promising results with regard to this topic have been reported in the last few years. Similar to other time-based interventions, including nutritional therapy or drug administration, time-of-day-based exercise may become a useful approach for the management of metabolic disorders. In this article, we review the role of exercise timing in metabolic health and discuss the potential mechanisms that could drive the metabolic-related benefits of physical exercise performed in a time-dependent manner.


Assuntos
Síndrome Metabólica , Humanos , Síndrome Metabólica/epidemiologia , Exercício Físico , Obesidade/terapia
14.
J Clin Med ; 12(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37510938

RESUMO

The aim of this study was to verify the effects of blood flow restriction on movement velocity and muscle activity during the back squat exercise. METHODS: Twenty-four university students participated in this study. In two randomized sessions 72 h apart, participants performed a 4-set protocol consisting of 30-15-15-15 repetitions performed at 30% of their one-repetition maximum in the back squat exercise. In both sessions, neuromuscular function was monitored by surface electromyography (EMG) and movement velocity (mean propulsive velocity (MPV), peak concentric velocity (Vmax), and the effort index (EI)). Blood flow restriction (BFR) was applied during exercise in one of the experimental sessions with 80% of full arterial occlusion pressure over lower limbs. RESULTS: The BFR condition showed higher (p < 0.05) EI, peak, and rooted mean square normalized EMG in Set 1 compared to Set 2. Similar MPV and Vmax were observed in each set for both the BFR and control conditions. No significant differences were observed between conditions in any set. CONCLUSIONS: BFR did not imply changes in neuromuscular performance during low-intensity resistance training, but it might induce greater intra-series velocity loss and less excitation of the muscles involved.

15.
Sci Rep ; 13(1): 19280, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935963

RESUMO

Handball is a team sport subjected to asymmetric actions that require high physical capacity demands on players. The development of large asymmetries could negatively affect sports performance. However, few studies have analyzed body composition and the force asymmetries in elite female handball players. The aim of this study was to analyze the presence of asymmetries based on limb dominance in body composition parameters and lower limb power in jumping performances in an elite women's handball team. An entire elite women's handball team, comprised by of 14 players, was analyzed. Dual X-ray Absorptiometry (DXA) and bioimpedance were used to analyze body composition. Force plates were used to evaluate jump performance. Results show the presence of differences between all the players in the different parameters of the CMJ jump. In addition, an asymmetry between the power of the dominant and non-dominant lower limb was observed between the players. The results show differences in muscle mass between the upper limbs, but not in the lower limbs in terms of both muscle and fat mass. However, there were no crossed asymmetries or significant differences between members based on dominance. The results suggest that the presence of asymmetries does not have to be one of the main parameters to be taken into account by coaches in elite athletes and to highlight the importance of including specific analyzes of body composition and sports performance in an individualized way.


Assuntos
Desempenho Atlético , Humanos , Feminino , Desempenho Atlético/fisiologia , Atletas , Extremidade Inferior , Composição Corporal , Extremidade Superior
16.
Front Mol Neurosci ; 16: 1106765, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293542

RESUMO

Previous studies have indicated that acute treatment with the monoamine stabilizer OSU-6162 (5 mg/kg), which has a high affinity for Sigma1R, significantly increased the density of accumbal shell D2R-Sigma1R and A2AR-D2R heteroreceptor complexes following cocaine self-administration. Ex vivo studies using the A2AR agonist CGS21680 also suggested the existence of enhanced antagonistic accumbal A2AR-D2R allosteric interactions after treatment with OSU-6162 during cocaine self-administration. However, a 3-day treatment with OSU-6162 (5 mg/kg) failed to alter the behavioral effects of cocaine self-administration. To test these results and the relevance of OSU-6162 (2.5 mg/kg) and/or A2AR (0.05 mg/kg) agonist interactions, we administered low doses of receptor agonists during cocaine self-administration and assessed their neurochemical and behavioral effects. No effects were observed on cocaine self-administration; however, marked and highly significant increases using the proximity ligation assay (PLA) were induced by the co-treatment on the density of the A2AR-D2R heterocomplexes in the nucleus accumbens shell. Significant decreases in the affinity of the D2R high- and low-affinity agonist binding sites were also observed. Thus, in low doses, the highly significant neurochemical effects observed upon cotreatment with an A2AR agonist and a Sigma1R ligand on the A2AR-D2R heterocomplexes and their enhancement of allosteric inhibition of D2R high-affinity binding are not linked to the modulation of cocaine self-administration. The explanation may be related to an increased release of ATP and adenosine from astrocytes in the nucleus accumbens shell in cocaine self-administration. This can lead to increased activation of the A1R protomer in a putative A1R-A2AR-D2R complex that modulates glutamate release in the presynaptic glutamate synapse. We hypothesized that the integration of changes in presynaptic glutamate release and postjunctional heteroreceptor complex signaling, where D2R plays a key role, result in no changes in the firing of the GABA anti-reward neurons, resulting in no reduction in cocaine self-administration in the present experiments.

17.
Artigo em Inglês | MEDLINE | ID: mdl-36231929

RESUMO

Reviews focused on the ketogenic diet (KD) based on the increase in fat-free mass (FFM) have been carried out with pathological populations or, failing that, without population differentiation. The aim of this review and meta-analysis was to verify whether a ketogenic diet without programmed energy restriction generates increases in fat-free mass (FFM) in resistance-trained participants. We evaluated the effect of the ketogenic diet, in conjunction with resistance training, on fat-free mass in trained participants. Boolean algorithms from various databases (PubMed, Scopus. and Web of Science) were used, and a total of five studies were located that related to both ketogenic diets and resistance-trained participants. In all, 111 athletes or resistance-trained participants (87 male and 24 female) were evaluated in the studies analyzed. We found no significant differences between groups in the FFM variables, and more research is needed to perform studies with similar ketogenic diets and control diet interventions. Ketogenic diets, taking into account the possible side effects, can be an alternative for increasing muscle mass as long as energy surplus is generated; however, their application for eight weeks or more without interruption does not seem to be the best option due to the satiety and lack of adherence generated.


Assuntos
Dieta Cetogênica , Treinamento Resistido , Atletas , Dieta Cetogênica/efeitos adversos , Feminino , Humanos , Hipertrofia , Masculino , Músculos
18.
J Int Soc Sports Nutr ; 19(1): 529-542, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966022

RESUMO

Background: Creatine monohydrate (CrM) supplementation has been shown to be an effective and safe nutritional supplement to improve performance; however, the impact of CrM supplementation in young basketball players is less clear. This study evaluated the effects of CrM supplementation during a strength and conditioning training (SCT) program on lower-limb strength parameters and performance in under-16 (U16) basketball players. Methods: Twenty-three male U16 basketball players participated in this study (14.3 ± 0.4 years; BMI: 20.7 ± 2.2 kg∙m-2). The players were randomly assigned to either a CrM group (n = 12) that ingested 0.1 g·kg-1·day-1 of CrM or to a non-supplemented control group (n = 11, CON). The athletes participated in an 8-week SCT program consisting of two lower-limb resistance-training sessions and two plyometric sessions per week. Squat jump (SJ), drop jump (DP), countermovement jump (CMJ), and Abalakov (ABK) jump power tests as well as basketball performance (points and minutes per game) were measured before, during and/or after the intervention. Data were analyzed using a general linear model with repeated measures with independent Student's t-test pairwise comparisons. Results: The results (95% confidence interval for mean change from baseline) show that there were significant differences for all variables for CrM and CON, respectively: SJ (cm): 2.6 - 6.4, P < 0.01 and 2.2-5.1 P < 0.01; DJ (cm): 2.5-5.6, P < 0.01, and 1.8-4.4, P < 0.01; CMJ (cm): 0.3-0.8, P < 0.01, and 0.2-0.5, P < 0.01; ABK (cm): 2.8-5.5, P < 0.01 and 0.7-2.6, P = 0.003. A significant group x time interaction (p = 0.003, ηp 2 = 0.342) was observed in ABK performance. No significant group x time effects were seen in squat jump (p = 0.449, ηp 2 = 0.028), drop jump (p = 0.143, ηp 2 = 0.099), or counter movement jump (p = 0.304, ηp 2 = 0.05). A significant interaction effect was also observed in points per game (p = 0.049, ηp 2 = 0.149), while a non-significant but medium effect was seen in minutes per game (p = 0.166, ηp 2 = 0.094). Conclusions: CrM supplementation in conjunction with resistance and plyometric training increased the lower-limb ABK power and scoring performance in U16 basketball players.


Assuntos
Desempenho Atlético , Basquetebol , Treinamento Resistido , Creatina , Humanos , Masculino , Força Muscular , Treinamento Resistido/métodos
19.
J Clin Med ; 11(17)2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-36079150

RESUMO

This study aimed to evaluate the effects of preceding anodal transcranial direct stimulation (a-tDCS) over the dorsolateral prefrontal cortex (DLPFC) during the back squat exercise on movement velocity and surface electromyographic (sEMG) activity. Thirteen healthy, well-trained, male firefighters (34.72 ± 3.33 years; 178 ± 7.61 cm; 76.85 ± 11.21 kg; 26.8 ± 4.2 kg·m−2; back squat 1-repetition maximum 141.5 ± 16.3 kg) completed this randomised double-blinded sham-controlled crossover study. After familiarisation and basal measurements, participants attended the laboratory on two occasions separated by 72 h to receive either Sham or a-tDCS (current intensity of 2 mA for 20 min). Immediately after stimulation, participants completed three sets of 12 repetitions (70% of 1-RM) with three minutes of recovery between sets monitored with a linear position transducer. The sEMG of the rectus femoris (RF) and vastus lateralis (VL) of both legs were recorded. No significant differences were observed between a-tDCS and Sham interventions on mean concentric velocity at any set (p > 0.05). Velocity loss and effort index were significantly higher (p < 0.05) in set 3 compared to set 1 only in the a-tDCS group. The right-leg RM and right-leg VL elicited the greatest muscle activation during set 1 after a-tDCS and Sham, respectively (p < 0.05). Our results revealed that a-tDCS over the DLPFC might impact movement velocity or fatigue tolerance in well-trained individuals. Notwithstanding, significant differences in dominant-leg muscle activity were found both in a-tDCS and Sham.

20.
Artigo em Inglês | MEDLINE | ID: mdl-35457392

RESUMO

INTRODUCTION: Undulating training has been investigated in sedentary and trained adults, but less is known about the influence of undulating training in older adults. PURPOSE: This study aimed to evaluate body composition, strength levels, and physical fitness in response to traditional or undulating training in older adults. METHODS: A controlled, double-arm trial was conducted in eighteen older adults (10 males, 8 females; 64 ± 2.1 years; 165.12 ± 7.5 cm; 72.5 ± 11.4 kg; 26.5 ± 3.2 k·gm-2) who were randomly assigned to traditional (n = 9, TT) or undulating training (n = 9, UT) for eight weeks. Dual X-ray absorptiometry was used to measure fat-free mass (FFM), fat mass (FM), and bone mineral density (BMD). Strength levels were evaluated by the handgrip strength and the one-repetition maximum in vertical chest press, rowing machine, squat, monopodal horizontal leg press, and leg extension. In addition, functional capacity was assessed using the Senior Fitness Test (SFT). Statistical analysis included mean/median comparisons to establish the difference after the intervention (paired Student's t-test or Wilcoxon test), and effect size calculations based on estimates. RESULTS: After correction for fat-free adipose tissue, a significant increase in FFM was observed in both groups, while no significant changes were found in FM and BMD. Upper- and lower-limbs strength showed significant increases in both groups, although clinical significance varied among exercises. Favorable results were seen on the cardiorespiratory fitness and strength components of the SFT in both groups. CONCLUSIONS: The 8-week UT and TT protocols are valid options for improving FFM and increasing strength and functional capacity in women and men over 60 years of age.


Assuntos
Treinamento Resistido , Idoso , Composição Corporal , Feminino , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Aptidão Física , Treinamento Resistido/métodos
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