Intramuscular adipose tissue, muscle area, and power as predictors of performance in breast cancer survivors.

PURPOSE: The decline in physical performance, assessed by physical tests such as the timed up and go (TUG) test, is a consequence of reduced physiological reserves at higher levels of a hierarchical process. This occurs due to changes in muscle architecture, including atrophy and fat infiltration into the muscles, which in turn lead to changes in muscle function, resulting in reduced muscle strength and power and, consequently, affecting physical performance. This study investigated predictive factors for physical performance in breast cancer survivor (BCS), focusing on intramuscular adipose tissue (IMAT), quadríceps muscle area (QMA), and muscular power. METHODS: This observational, analytical, and cross-sectional study included 23 women without a history of cancer (age, 58.5 ± 8.3 years; BMI, 27.2 ± 5.1 kg/m2) and 56 BCS (age, 58.5 ± 8.3 years; BMI, 27.2 ± 5.1 kg/m2). QMA and IMAT were assessed using computed tomography images. Muscular power and physical performance were measured using the 5-repetition sit-to-stand and TUG tests, respectively. RESULTS: IMAT (r = 0.4, P < 0.01) and muscular power (r = - 0.4, P < 0.01) were associated with TUG performance in BCS, whereas QMA (r = - 0.22, P = 0.10) showed no significant association. QMA (r = 0.55, P < 0.01) was associated with muscular power, while no significant association was found between IMAT and muscular power (r = - 0.05, P = 0.73). Age explained 19% (P < 0.01) of TUG performance variability. Adding muscular power increased explanatory power by 12% (P < 0.01), and including IMAT further increased it by 7% (P = 0.02) for TUG performance. Collectively, age, muscular power, and IMAT accounted for 38% of the performance variance in the TUG test (age, B = 0.06, P = 0.043; muscular power, B = - 0.01, P = 0.002; IMAT, B = - 0.05, P = 0.020). CONCLUSIONS: Our findings suggest that IMAT and muscular power predict the physical performance of BCS, while QMA does not have the same predictive capability.

Propulsive forces and muscle activation during gait: comparisons between premenopausal and postmenopausal midlife women.

OBJECTIVE: The aim of this study was to investigate whether there is a reduction in propulsive force during gait in postmenopausal women compared with premenopausal women. METHODS: Forty-four women (21 premenopausal and 23 postmenopausal women) aged 40 to 55 years were selected. The ability to reach peak propulsive forces was assessed during the step execution test. The test was performed at the usual speed on 2 nonconsecutive days, with two attempts per day, using a force platform. Four temporal parameters were defined and calculated: initiation phase, preparation phase, swing phase, and total time. Peak force (anteroposterior and vertical) and time to reach peak force were obtained in both preparation and swing phases. The rate of force development was defined as peak force divided by time to reach peak force. RESULTS: The postmenopausal women group presented a longer time in the preparation phase (540.6 ± 77 ms vs 482.5 ± 93 ms, P = 0.024) and consequently a longer total time in the step execution test (1,191 ± 106.4 ms vs 1,129 ± 114.3 ms, P = 0.045). There were differences between the groups for the rate of force development in the anteroposterior (postmenopausal women, 142.5 ± 38.1 N/s vs premenopausal women, 174.7 ± 70.5 N/s; P = 0.022) and vertical directions in the preparation phase (postmenopausal women, 102.7 ± 62.3 N/s vs premenopausal women, 145.3 ± 71 N/s; P = 0.012). No significant differences ( P > 0.05) were found in force, time to peak force, and rate of force development during the swing phase. In addition, there were no observed differences in surface electromyography of the medial and lateral gastrocnemius muscles during the preparation phase and swing phase of the step execution test between the two groups. CONCLUSIONS: Postmenopausal women exhibited lower ability to generate propulsive force rapidly (rates of force development) in both the anteroposterior and vertical directions during the preparation phase of gait compared with premenopausal women. This indicates that postmenopausal women experience a reduction in propulsive force during gait.

Association between physical and cognitive function in post menopause: a cross-sectional study / Associação entre função física e cognitiva na pós-menopausa: um estudo transversal

Functional tests have been performed to predict cognitive decline in postmenopausal women and may be an important tool to identify early reductions in cognitive performance in this population. However, it is still unclear which functional test is more sensitive for detecting cognitive decline in the investigated sample. The aim of this study was to verify the association between functional per-formance and cognitive function in postmenopausal women and to analyze whether the gait speed of 400 meters (400wt) and Timed Up and Go (TUG) tests are predictors of cognitive function in this sample. One hundred and twenty-eight postmenopausal women (60.8 ± 7.9 years) participated in this cross-sectional study. Body composition was assessed using Dual Energy X-ray Absorpti-ometry (DXA), functional performance by the TUG and 400wt tests, cognitive performance by the Montreal Cognitive Assessment (MoCA) test and muscle strength by maximum voluntary isometric contraction (MVIC) in lower limbs. An association between functional performance and cognitive function was observed in middle-aged postmenopausal women. The TUG test was associated with the MoCA test (B = -0.79; SE = 0.29; p = 0.008). However, no association was observed between 400wt with the MoCA test (B = 3.03; SE = 1.92; p = 0.117). These results show that the TUG test is a good predictor of cognitive decline in postmenopausal middle-aged women

Testes funcionais têm sido realizados para predizer declínio cognitivo em mulheres na pós-menopausa e podem ser uma ferramenta importante para identificar reduções precoces no desempenho cognitivo nessa população. No entanto, ainda não está claro qual teste funcional é mais sensível para detectar precocemente o declínio cognitivo na amostra investigada. O objetivo deste estudo foi verificar se há associação entre desempenho funcional e função cognitiva em mulheres na pós-menopausa e analisar se os testes de velocidade de marcha de 400 metros ( Vm400) e Timed Up and Go (TUG) são preditores da função cognitiva nesta amostra. Cento e vinte oito mulheres na pós-menopausa (60,8 ± 7,9 anos) participaram deste estudo de carácter transversal. A composição corporal foi avaliada pela Absorciometria Radiológica de Dupla Energia (DXA), desempenho funcional pelos testes Vm400 e TUG, desempenho cognitivo pelo teste Montreal Cognitive Assessment (MoCA) e força muscular pela contração isométrica voluntaria máxima (CIVM) dos membros inferiores. Uma associação entre desempenho funcional e função cognitiva foi observada na amostra investigada. O teste TUG foi associado ao teste MoCA (B = -0,79; SE = 0,29; p = 0,008). No entanto, não foi observada associação entre Vm400 com o teste MoCA (B = 3,03; SE = 1,92; p = 0,117). Esses resultados mostram que o teste TUG é um bom preditor de declínio cognitivo em mulheres na pós-menopausa na meia idade

Resistance Training Volume Enhances Muscle Hypertrophy, but Not Strength in Postmenopausal Women: A Randomized Controlled Trial.

ABSTRACT: Nascimento de Oliveira Júnior, G, de Freitas Rodrigues de Sousa, J, Augusto da Silva Carneiro, M, Martins, FM, Santagnello, SB, Campos Souza, MV, and Orsatti, FL. Resistance training volume enhances muscle hypertrophy, but not strength in postmenopausal women: a randomized controlled trial. J Strength Cond Res 36(5): 1216-1221, 2022-Among several possible resistance training (RT) variables to be manipulated, the training volume has been considered as a critical variable to maximize RT-induced hypertrophy. Many of the studies that compared one set of RT with 3 sets have failed to show a difference in muscle hypertrophy in older adults. However, it is not clear whether further increases in RT volume (i.e., 6 sets) would result in even greater RT-related hypertrophy than 3 sets in older adults. This study aimed to investigate whether higher-volume RT (HV-RT) maximizes gains in lean body mass and muscle strength (MS) when compared with lower-volume RT (LV-RT) in postmenopausal women (PW). Fifty-eight PW were randomized into 1 of the 3 groups: control group (CT, no exercise), HV-RT (6 sets per exercise), and LV-RT (3 sets per exercise). Volunteers took part in a supervised training program (leg press 45°, leg extension, leg curl and standing calf raises) and were assessed for leg lean mass (LLM; dual X-ray absorptiometry) and lower limb MS (leg press and leg extension; 1 repetition maximum [1RM]) before and after 12 weeks of RT. Both HV-RT and LV-RT groups increased (p < 0.05) LLM and MS when compared with the CT group. Higher increases in LLM gains were observed for the HV-RT group when compared with the LV-RT group (6.1 and 2.3%, p < 0.001). Both HV-RT and LV-RT groups similarly increased 1RM in the leg press and leg extension. Thus, there seems to be a dose-response relationship between RT volume and muscle hypertrophy, but not for MS gains in PW.

Determination of individual glucose threshold using pharmacy portable blood glucose meter / Determinação do limiar glicêmico individual com o uso de glicosímetro portátil de farmácia / Determinación del umbral glucémico individual con el uso de glucómetro portátil de farmacia

ABSTRACT Introduction The individual glucose threshold (IGT) has been used to estimate the anaerobic threshold with low-cost analyses and shorter times. However, the reliability of the glycemic analysis using a portable pharmacy glucose meter has received little attention. Objective To identify the IGT using a portable glucose meter and to compare it with the ventilatory threshold (VT). Methods Fourteen active, healthy men (25.9 ± 3.2 years; %BF = 17.9 ± 3.7%) performed an incremental treadmill test. The anaerobic threshold was identified by two different methods: (1) IGT, corresponding to the intensity of the lowest glucose value during the test; and (2) VT, corresponding to the break in linearity of the ventilation curve and an increase in the respiratory oxygen equivalent, without an equivalent increase in carbon dioxide. Results There were significant differences between VT (9.9 ± 1.2 km/h) and IGT (9.5 ± 1/1 km/h), corresponding to 75.4 ± 9.2 and 72.5 ± 10.4 %VO2max, respectively. The methods presented high correlation (r = 0.82, p = 0.002) and the Bland-Altman technique showed agreement between IGT and VT, with a mean difference of 0.5 km/h. Conclusion It was possible to determine the intensity of IGT by the glycemic response in the incremental test using a portable glucose meter. The IGT underestimated the intensity of VT by approximately 0.5 km/h, but with a high correlation and agreement between them. Level of evidence III, Case-Controle Study.

RESUMO Introdução O limiar glicêmico individual (LGI) tem sido utilizado para estimar o limiar anaeróbico com baixo custo das análises e também em menor tempo. Entretanto, dá-se pouca atenção para a confiabilidade das análises glicêmicas por meio do glicosímetro portátil de farmácia. Objetivo Determinar o LGI por meio de glicosímetro portátil e comparar com o limiar ventilatório (LV). Métodos: Catorze homens saudáveis e ativos (25,9 ± 3,2 anos; %G = 17,9 ± 3,7%) realizaram teste incremental em esteira. Determinou-se o limiar anaeróbico por duas metodologias: (1) LGI, correspondendo à intensidade do menor valor glicêmico durante o teste; (2) LV, correspondendo à quebra da linearidade da curva da ventilação e aumento do equivalente respiratório de oxigênio sem aumento do equivalente de dióxido de carbono. Resultados Foram observadas diferenças significativas entre LV (9,9 ± 1,2 km/h) e LGI (9,5 ± 1,1 km/h), correspondendo a 75,4 ± 9,2 e 72,5±10,4 %VO2máx, respectivamente. As duas metodologias apresentaram correlação alta (r = 0,82; p = 0,002) entre si. A técnica de Bland-Altman evidenciou concordância entre os métodos LGI e LV, com uma diferença média de 0,5 km/h. Conclusão Foi possível determinar a intensidade do LGI por meio da resposta glicêmica em teste incremental com o uso de glicosímetro portátil de farmácia. O LGI subestimou em aproximadamente 0,5 km/h a intensidade do LV, no entanto, com alta correlação e concordância entre eles. Nível de evidência III, Estudo de Caso-controle.

RESUMEN Introducción El umbral glucémico individual (UGI) ha sido utilizado para estimar el umbral anaeróbico con bajo costo de los análisis y también en menor tiempo. Sin embargo, se presta poca atención a la confiabilidad de los análisis glucémicos a través del glucómetro portátil de farmacia. Objetivo Determinar el UGI a través de glucómetro portátil y comparar con el umbral de ventilación (UV). Métodos Catorce hombres sanos y activos (25,9 ± 3,2 años; %G = 17,9 ± 3,7%) realizarán una prueba incremental en cinta. El umbral anaeróbico se determinó mediante dos metodologías: (1) UGI correspondiente a la intensidad del valor glucémico más bajo durante la prueba; (2) UV, correspondiente a la quiebra de la linealidad de la curva de la ventilación y aumento del equivalente respiratorio de oxígeno sin aumento del equivalente de dióxido de carbono. Resultados Se observaron diferencias significativas entre UV (9,9 ± 1,2 km/h) y UGI (9,5 ± 1,1 km/h), correspondiendo a 75,4 ± 9,2 y 72,5 ± 10,4, %VO2max, respectivamente. Las dos metodologías presentaron una correlación alta (r = 0,82, p = 0,002) entre sí. La técnica de Bland-Altman evidenció concordancia entre los métodos UGI y UV, con una diferencia media de 0,5 km/h. Conclusión Fue posible determinar la intensidad del UGI por medio de la respuesta glucémica en prueba incremental con el uso de glucómetro portátil de farmacia. El UGI subestimó en aproximadamente 0,5 km/h la intensidad del UV, sin embargo, con alta correlación y concordancia entre ellos. Nivel de evidencia III, Estudio de caso-control.

Wearing Colored Glasses can Influence Exercise Performance and Testosterone concentration?

Perception of red color is associated with higher testosterone concentration and better human performance. Thus, we evaluated the acute effects of wearing colored-lens glasses on the YoYo intermittent endurance exercise test 2 (YoYoIE2) performance indicators and testosterone concentration. Ten soccer players performed three YoYoIE2 (counterbalanced crossover) wearing colorless (control), blue- or red-lensed glasses (2-4 days of rest in between). YoYoIE2 performance did not differ among the trials ( p >0.05), but blood testosterone increased post-exercise in red compared to red baseline (red=14%, effect size=0.75). Analysis showed faster heart rate recovery ( p <0.05) at 1 min post-test for blue compared to red lenses. Rating of perceived exertion and blood lactate concentration did not differ ( p >0.05) among the trials. Wearing red-colored lenses during high-intensity intermittent exercise increased testosterone concentration, but do not influence performance.

Resistance training and caloric restriction prevent systolic blood pressure rise by improving the nitric oxide effect on smooth muscle and morphological changes in the aorta of ovariectomized rats.

In this study, we investigated the effects of resistance training (RT), caloric restriction (CR), and the association of both interventions in aortic vascular reactivity and morphological alterations, matrix metalloproteinase-2 (MMP-2) activity, insulin resistance and systolic blood pressure (SBP) in ovariectomized rats. Fifty female Holtzman rats were subjected to ovariectomy and Sham surgery and distributed into the following groups: Sham-sedentary, ovariectomized-sedentary, ovariectomized-resistance training, ovariectomized-caloric restriction, and ovariectomized-resistance training and caloric restriction groups. RT and 30% CR protocols were performed for 13 weeks. Analyses were conducted to evaluate the following: acetylcholine and sodium nitroprusside-induced relaxation of aortic rings, MMP-2 activity, insulin tolerance test, highlighting of the aorta wall cross-sectional area by hematoxylin-eosin stain, aorta vessel remodeling and SBP. We observed that ovariectomy decreased the potency of dependent and independent endothelium relaxation and MMP-2 activity, prevented insulin resistance, promoted aorta vessel remodeling in the cross-sectional area, and promoted the media-to-lumen ratio, the collagen content, and the alteration of the structure and elastic fibers of the vessel. The effects of the ovariectomy could contribute to SBP increases. However, the association of exercise and diet improved the relaxation potency in dependent and independent endothelium relaxation, elevated MMP-2 activity, ameliorate insulin sensitivity, increased the aorta cross-sectional area and media-to-lumen ratio, decreased collagen content and promoted histological parameters of the aorta vessel wall, preventing the increase of SBP. CONCLUSION: Our study revealed that the RT and CR separately, and even associatively, improved vascular function, activated MMP-2, and produced a beneficial hypertrophic remodeling, preventing the elevation of SBP in ovariectomized rats.

Effects of resistance training and estrogen replacement on adipose tissue inflammation in ovariectomized rats.

Estrogen deficiency is directly related to central obesity and low-grade inflammation. Hormonal replacement and exercise training are both able to decrease fat accumulation and inflammation in postmenopausal women. However, the efficiency of resistance training (RT) and estrogen replacement (ER) in minimizing adiposity and inflammation in the visceral adipose tissue (VAT) of ovariectomized (OVX) rats has not yet been elucidated. In this study, Sprague-Dawley rats were divided into the following 6 groups: sham-operated sedentary (Sham-Sed), OVX-Sed, Sham-RT, OVX-RT, OVX-Sed-ER, and OVX-RT-ER groups. ER was performed by implanting silastic capsules containing 17ß-estradiol. For RT, the animals were required to climb a 1.1-m vertical ladder with conical flasks containing weights attached to their tails for 12 weeks. Histological analyses were used to evaluate morphological changes. Gene expression levels were determined by quantitative real-time reverse transcriptase polymerase chain reaction, and protein concentrations were determined using Multiplex/Luminex assays. Ovariectomy increased the body mass (BM), adipocyte area, and inflammation in the VAT, the latter of which was indicated by reduced interleukin-10 (48%) and increased tumor necrosis factor (TNF)-α concentration (∼3%). RT efficiently decreased BM, adipocyte area, and inflammation in the OVX groups. The combination of RT and ER decreased BM (19%) and the TNF-α concentration (18%) and increased the gene and protein expression levels of adiponectin (173% and 18%). These results indicate that RT and the combination of RT and ER are efficient strategies for reducing the BM and improving the inflammatory status of OVX rats.

Resistance training improves body composition and increases matrix metalloproteinase 2 activity in biceps and gastrocnemius muscles of diet-induced obese rats.

OBJECTIVE: We investigated the influence of resistance training on body composition and matrix metalloproteinase 2 activity in skeletal muscles of rats fed a high-fat diet. METHODS: Thirty-two Wistar rats were divided into four experimental groups (n = 8/each) according to diet and exercise status: Control (standard diet), Obese Control (high-fat diet), Resistance Training (standard diet) and Obese Resistance Training (high-fat diet) groups. Animals were fed a high-fat diet for 12 weeks to promote excessive weight gain. Resistance Training groups performed 12 weeks of training periods after this period in a vertical ladder three times/week. Fat percentage, fat-free mass and fat mass were assessed using dual-energy X-ray absorptiometry, and matrix metalloproteinase 2 activity in biceps and gastrocnemius muscles was analyzed using zymography. RESULTS: Resistance training significantly reduced body and fat masses and fat percentages in both trained groups (p<0.05). The maximal carrying load between trained groups was not different, but relative force was higher in the Resistance Training group (p<0.05). Of note, increased matrix metalloproteinase 2 activity was noted in the tested muscles of both trained groups (p<0.05). CONCLUSION: In conclusion, altered body composition and muscle matrix metalloproteinase 2 activity promoted by excessive weight gain were positively modified by resistance training.

Resistance training improves body composition and increases matrix metalloproteinase 2 activity in biceps and gastrocnemius muscles of diet-induced obese rats

OBJECTIVE: We investigated the influence of resistance training on body composition and matrix metalloproteinase 2 activity in skeletal muscles of rats fed a high-fat diet. METHODS: Thirty-two Wistar rats were divided into four experimental groups (n = 8/each) according to diet and exercise status: Control (standard diet), Obese Control (high-fat diet), Resistance Training (standard diet) and Obese Resistance Training (high-fat diet) groups. Animals were fed a high-fat diet for 12 weeks to promote excessive weight gain. Resistance Training groups performed 12 weeks of training periods after this period in a vertical ladder three times/week. Fat percentage, fat-free mass and fat mass were assessed using dual-energy X-ray absorptiometry, and matrix metalloproteinase 2 activity in biceps and gastrocnemius muscles was analyzed using zymography. RESULTS: Resistance training significantly reduced body and fat masses and fat percentages in both trained groups (p<0.05). The maximal carrying load between trained groups was not different, but relative force was higher in the Resistance Training group (p<0.05). Of note, increased matrix metalloproteinase 2 activity was noted in the tested muscles of both trained groups (p<0.05). CONCLUSION: In conclusion, altered body composition and muscle matrix metalloproteinase 2 activity promoted by excessive weight gain were positively modified by resistance training. .

Estudo do comportamento cortisol, gh e insulina apos uma sessao de exercicio resistido agudo / Study of the behavior of cortisol, gh and insulin after a session of acute resisted exercise / Estudio del comportamiento de cortisol, gh e insulina despues de uma sesion de ejercicio resistido agudo

INTRODUÇÃO: Muitos trabalhos têm estudado o comportamento hormonal nos exercício resistido, entretanto poucos relacionam os hormônios cortisol, GH e insulina. OBJETIVO: Estudar os ajustes das concentrações plasmáticas dos hormônios cortisol, GH e insulina em exercícios resistidos de mesma intensidade com relação à massas musculares distintas. MÉTODOS: Dez voluntários, com 20,3 ± 4,2 anos, 74,1 ± 10,2 kg de peso, 177,2 ± 4,6 cm de estatura e 23,8 ± 3,2 kg/m2 de IMC, realizaram uma sessão de leg press (LP) e supino reto (SR) com quatro séries com 10 repetições a 70% 1 RM com três minutos de intervalo. Foram coletadas amostras de sangue para dosagem das concentrações plasmáticas de cortisol, GH e insulina em repouso (Pré) e em 0' (Rec. 0'), 30' (Rec. 30') e 90' (Rec. 90') de recuperação. RESULTADOS: As concentrações plasmáticas de cortisol foram significativamente reduzidas ao final da recuperação em LP (2,20±0,37 ng/dl para 1,33±0,38ng/dl) em relação à pré-dosagem. As concentrações de GH e insulina elevaram-se significativamente durante a recuperação. GH em LP foi significativamente maior em Rec. 0' (2,75±3,29 ng/ml para 9,60±5,32 ng/dl) do que em pré. A insulina elevou-se significativamente em Rec. 30' em LP (14,70±7,92 ulU/ml para 21,66 ± 8,61 ulU/ml) e em SR (6,17 ± 2,99 ulU/ml para 19,70 ± 13,8 ulU/ml) em relação à pré. As concentrações plasmáticas de insulina pré em LP foram significativamente superiores a SR (14,70 ulU/ml e 6,17 ± 2,99 ulU/ml). CONCLUSÃO: O exercício resistido promoveu diferentes ajustes nas concentrações hormonais de cortisol, GH e insulina durante o período de recuperação. .

INTRODUCTION: Many works have studied the hormonal behavior in resistance exercise, however, few relate the cortisol, GH and insulin hormones. OBJECTIVE: To study the adjustments of plasma concentrations of the cortisol, GH and insulin hormones in resisted exercises of the same relative intensity with different muscle musses. METHODS: Ten volunteers, aged 20.3 ± 4.2 years, weight 74.1 ± 10.2 Kg, 177.2 ± 4.6 cm of stature and 23.8 ± 3.2 Kg/m2 of BMI, underwent a session of leg press (LP) and bench press (BP) with four sets of 10 repetitions at 70% 1 RM with three minutes apart. We collected blood samples to measure plasma concentrations of cortisol, GH and insulin at rest (Pre) and 0' (Rec. 0'), 30' (Rec. 30') and 90' (Rec. 90') of recovery. RESULTS: Plasma concentrations of cortisol decreased significantly at the end of the recovery in LP (2.20 ± 0.37 ng/dl to 1.33 ± 0.38 ng/dl) compared to pre. The GH and insulin concentrations significantly increased during recovery. GH was significantly higher in LP Rec. 0' (2.75 ± 3.29 ng/ml to 9.60 ± 5.32 ng/dl) than in pre. Insulin was significantly elevated in Rec. 30' in LP (14.70 ± 7.92 ulU/ml to 21.66 ± 8.61 ulU/ml) and BP (6.17 ± 2.99 ulU/ml to 19.70 ± 13.8 ulU/ml) for pre. The plasma insulin concentrations pre PL were significantly higher in the BP (14.70 ulU/ml and 6.17 ± 2.99 ulU/ml). CONCLUSION: Resisted exercise promoted different adjustments in hormone concentrations of cortisol, GH and insulin during the recovery period. .

INTRODUCCIÓN: Muchos trabajos han estudiado el comportamiento hormonal en el ejercicio de resistencia, sin embargo, pocos se refieren el cortisol, GH y las hormonas insulina. OBJETIVO: Estudiar los ajustes de las concentraciones plasmáticas de las hormonas cortisol, GH e insulina en ejercicios resistidos, de igual intensidad, en relación con las masas musculares diferentes. MÉTODOS: Diez voluntarios, con 20,3 ± 4,2 años, 74,1 ± 10,2 kg de peso, 177,2 ± 4,6 cm de estatura y 23,8 ± 3,2 kg/m2 de IMC, realizaron una sesión de leg press (LP) y supino recto (SR) con cuatro series, de 10 repeticiones a 70% 1 RM, con tres minutos de intervalo. Se recolectaron muestras de sangre para dosificación de las concentraciones plasmáticas de cortisol, GH e insulina en reposo (Pré) y en 0' (Rec. 0'), 30' (Rec. 30') y 90' (Rec. 90') de recuperación. RESULTADOS: Las concentraciones plasmáticas de cortisol se redujeron significativamente al final de la recuperación en LP (2,20±0,37 ng/dl para 1,33±0,38ng/dl) en relación con la predosificación. Las concentraciones de GH e insulina aumentaron significativamente durante la recuperación. GH en LP fue significativamente mayor en Rec. 0' (2,75±3,29 ng/ml para 9,60±5,32 ng/dl) en comparación con la predosificación. La insulina se elevó significativamente en Rec. 30' en LP (14,70±7,92 ulU/ml para 21,66 ± 8,61 ulU/ml) y en SR (6,17 ± 2,99 ulU/ml para 19,70 ± 13,8 ulU/ml) en relación con la predosificación. Las concentraciones plasmáticas de insulina, predosificación, en LP fueron significativamente superiores a SR (14,70 ulU/ml y 6,17 ± 2,99 ulU/ml). CONCLUSIÓN: El ejercicio resistido causó diferentes ajustes en las concentraciones hormonales de cortisol, GH e insulina durante el período de recuperación. .

Resistance training restores the gene expression of molecules related to fat oxidation and lipogenesis in the liver of ovariectomized rats.

Decreased levels of estrogen are associated with hepatic steatosis (HS), through changes in gene expression of molecules related to fat oxidation and lipogenesis. Both resistance training (RT) and endurance training (ET) prevent HS in ovariectomized (Ovx) rats. However, the molecular events associated with this process were only investigated for ET, but not for RT. Thus, the aim of this study was to investigate the effects of Ovx and RT on the gene expression of molecules related to fat oxidation and lipogenesis in the liver of rats. Sprague-Dawley adult female rats were grouped into four (n = 6 per group): sham-operated sedentary (Sham-Sed); Ovx sedentary (Ovx-Sed); sham-Rt and Ovx-Rt. A 10-week RT period, during which the animals climbed a 1.1-m vertical ladder with weights attached to their tails, was used. The sessions were performed three times a week, with 4-9 climbs and 8-12 dynamic movements per climb. Gene expression was analyzed by RT-PCR by the ∆∆Ct method. The estrogen deficiency associated with ovariectomy decreased the gene expression of molecules related to fat oxidation, carnitine palmitoyltransferase I (53%) and ß-hydroxyacyl-CoA dehydrogenase (27%), and increased molecules related to lipogenesis, sterol regulatory element-binding protein-1c (106%), acetyl-CoA carboxylase (ACC) (72%) and stearoyl CoA desaturase-1 (109%). With the exception of ACC, the ovariectomy-induced changes in the expression of these molecules were restored by RT. The present results indicate that RT has important effects on the prevention of HS in Ovx animals, through changes in gene expression of molecules related to hepatic lipid metabolism.