Ana Gomez | Facultad de derecho Udelar (original) (raw)

Papers by Ana Gomez

Journal of Strength and Conditioning Research, 2002

The object of this study was to examine changes in muscular strength, power, and resting hormonal... more The object of this study was to examine changes in muscular strength, power, and resting hormonal concentrations during 6 weeks of detraining (DTR) in recreationally strengthtrained men. Each subject was randomly assigned to either a DTR (n ϭ 9) or resistance training (RT; n ϭ 7) group after being matched for strength, body size, and training experience. Muscular strength and power testing, anthropometry, and blood sampling were performed before the experimental period (T1), after 3 weeks (T2), and after the 6-week experimental period (T3). One-repetition maximum (1RM) shoulder and bench press increased in RT at T3 (p Յ 0.05), whereas no significant changes were observed in DTR. Peak power output and mean power output significantly decreased (9 and 10%) in DTR at T2. Peak torque of the elbow flexors at 90Њ did not change in the RT group but did significantly decrease by 11.9% at T3 compared with T1 in the DTR group. Vertical jump height increased in RT at T2 but did not change in DTR. Neither group displayed any changes in 1RM squat, body mass, percent body fat, or resting concentrations of growth hormone, follicle-stimulating hormone, luteinizing hormone, sex hormone-binding globulin, testosterone, cortisol, or adrenocorticotropin. These data demonstrate that 6 weeks of resistance DTR in recreationally trained men affects power more than it does strength without any accompanying changes in resting hormonal concentrations. For the recreational weight trainer, losses in strength over 6 weeks are less of a concern compared with anaerobic power and upper arm isometric force production. Anaerobic power exercise with a high metabolic component coming from glycolysis might be of importance for reducing the impact of DTR on Wingate power performances. A minimal maintenance training program is recommended for the recreational lifter to offset any reductions in performance. . Detraining produces minimal changes in physical performance and hormonal variables in recreationally strength-trained men.

Objective: Very low-carbohydrate diets are widely used for weight loss yet few controlled studies... more Objective: Very low-carbohydrate diets are widely used for weight loss yet few controlled studies have determined how these diets impact cardiovascular risk factors compared to more traditional low-fat weight loss diets. The primary purpose of this study was to compare a very low-carbohydrate and a low-fat diet on fasting blood lipids, LDL subclasses, postprandial lipemia, and insulin resistance in overweight and obese women.

Medicine and Science in Sports and Exercise, 2002

Very low-carbohydrate (ketogenic) diets are popular yet little is known regarding the effects on ... more Very low-carbohydrate (ketogenic) diets are popular yet little is known regarding the effects on serum biomarkers for cardiovascular disease (CVD). This study examined the effects of a 6-wk ketogenic diet on fasting and postprandial serum biomarkers in 20 normal-weight, normolipidemic men. Twelve men switched from their habitual diet (17% protein, 47% carbohydrate and 32% fat) to a ketogenic diet (30% protein, 8% carbohydrate and 61% fat) and eight control subjects consumed their habitual diet for 6 wk. Fasting blood lipids, insulin, LDL particle size, oxidized LDL and postprandial triacylglycerol (TAG) and insulin responses to a fat-rich meal were determined before and after treatment. There were significant decreases in fasting serum TAG (Ϫ33%), postprandial lipemia after a fat-rich meal (Ϫ29%), and fasting serum insulin concentrations (Ϫ34%) after men consumed the ketogenic diet. Fasting serum total and LDL cholesterol and oxidized LDL were unaffected and HDL cholesterol tended to increase with the ketogenic diet (ϩ11.5%; P ϭ 0.066). In subjects with a predominance of small LDL particles pattern B, there were significant increases in mean and peak LDL particle diameter and the percentage of LDL-1 after the ketogenic diet. There were no significant changes in blood lipids in the control group. To our knowledge this is the first study to document the effects of a ketogenic diet on fasting and postprandial CVD biomarkers independent of weight loss. The results suggest that a short-term ketogenic diet does not have a deleterious effect on CVD risk profile and may improve the lipid disorders characteristic of atherogenic dyslipidemia.

Journal of Strength and Conditioning Research, 2004

Hypoenergetic very low-carbohydrate and low-fat diets are both commonly used for short-term weigh... more Hypoenergetic very low-carbohydrate and low-fat diets are both commonly used for short-term weight loss; however, few studies have directly compared their effect on blood lipids, with no studies to our knowledge comparing postprandial lipemia, an important independently identified cardiovascular risk factor. The primary purpose of this study was to compare the effects of a very low-carbohydrate and a low-fat diet on fasting blood lipids and postprandial lipemia in overweight men. In a balanced, randomized, crossover design, overweight men (n ϭ 15; body fat Ͼ25%; BMI, 34 kg/m 2 ) consumed 2 experimental diets for 2 consecutive 6-wk periods. One was a very low-carbohydrate (Ͻ10% energy as carbohydrate) diet and the other a low-fat (Ͻ30% energy as fat) diet. Blood was drawn from fasting subjects on separate days and an oral fat tolerance test was performed at baseline, after the very low-carbohydrate diet period, and after the low-fat diet period. Both diets had the same effect on serum total cholesterol, serum insulin, and homeostasis model analysis-insulin resistance (HOMA-IR). Neither diet affected serum HDL cholesterol (HDL-C) or oxidized LDL (oxLDL) concentrations. Serum LDL cholesterol (LDL-C) was reduced (P Ͻ 0.05) only by the low-fat diet (Ϫ18%). Fasting serum triacylglycerol (TAG), the TAG/HDL-C ratio, and glucose were significantly reduced only by the very low-carbohydrate diet (Ϫ44, -42, and -6%, respectively). Postprandial lipemia was significantly reduced when the men consumed both diets compared with baseline, but the reduction was significantly greater after intake of the very low-carbohydrate diet. Mean and peak LDL particle size increased only after the very low-carbohydrate diet. The short-term hypoenergetic low-fat diet was more effective at lowering serum LDL-C, but the very low-carbohydrate diet was more effective at improving characteristics of the metabolic syndrome as shown by a decrease in fasting serum TAG, the TAG/HDL-C ratio, postprandial lipemia, serum glucose, an increase in LDL particle size, and also greater weight loss (P Ͻ 0.05). J. Nutr. 134: 880 -885, 2004.

Antimicrobial Agents and Chemotherapy, 2004

Science, 1997

5ites along run-of-r~\-er ~mpoiundments (n = 13). the mean sarn~3le scores tor tlie tlrst DCX axl... more 5ites along run-of-r~\-er ~mpoiundments (n = 13). the mean sarn~3le scores tor tlie tlrst DCX axls LliJ not d~ffer from thixe ot free-tlo~iiny sites (115.8 versus 1Q2.7, P = Q.c79i), <ugye.;t-~n g that tlorlst~c recover\-may occur.

Proceedings of The National Academy of Sciences, 1997

Our recent data show that in cardiac myocytes polyunsaturated fatty acids (PUFAs) are antiarrhyth... more Our recent data show that in cardiac myocytes polyunsaturated fatty acids (PUFAs) are antiarrhythmic. They reduce I(Na), shorten the action potential, shift the threshold for excitation to more positive potentials, and prolong the relative refractory period. In this study we use patch-clamp techniques in whole-cell mode and confocal Ca2+ imaging to examine the effects of PUFAs on the voltage-gated L-type Ca2+ current (I(Ca,L)), elementary sarcoplasmic reticulum Ca2+-release events (Ca2+-sparks), and [Ca2+]i transients in isolated rat ventricular myocytes. Extracellular application of eicosapentaenoic acid (EPA; C20:5 n - 3) produced a prompt and reversible concentration-dependent suppression of I(Ca,L). The concentration of EPA to produce 50% inhibition of I(Ca) was 0.8 microM in neonatal rat heart cells and 2.1 microM in adult ventricular myocytes. While the EPA induced suppression of I(Ca,L), it did not significantly alter the shape of the current-voltage relation but did produce a small, but significant, negative shift of the steady-state inactivation curve. The inhibition of I(Ca,L) was voltage- and time-dependent, but not use- or frequency-dependent. Other PUFAs, such as docosahexaenoic acid, arachidonic acid, linolenic acid, linoleic acid, conjugated linoleic acid, and eicosatetraynoic acid had similar effects on I(Ca,L) as EPA. All-trans-retinoic acid, which had been shown to suppress induced arrhythmogenic activity in rat heart cells, also produced a significant inhibition of I(Ca,L). The saturated stearic acid and the monounsaturated oleic acid had no effect on I(Ca,L). Because both I(Ca,L) and sarcoplasmic reticulum Ca2+-release underlie many cardiac arrhythmias, we examined the effects of EPA on I(Ca,L) and Ca2+-sparks. While EPA suppressed both, it did not change the temporal or spatial character of the Ca2+-sparks, nor did it alter the ability of I(Ca,L) to trigger Ca2+-sparks. We conclude that PUFAs may act as antiarrhythmic agents in vivo in normal and Ca2+-overloaded cells principally because they reduce Ca2+ entry by blocking I(Ca,L). Furthermore, PUFAs act directly to decrease I(Na) and I(Ca,L), but indirectly to reduce the [Ca2+]i transients and [Ca2+]i-activated membrane current. Although a negative inotropic action is associated with application of PUFAs, it is clear that by reducing I(Ca,L), I(Na) and Ca2+-sparks, PUFAs can reduce spontaneous extrasystoles in the heart. The mechanisms by which PUFAs act are discussed.

La Administración Pública es el contenido esencial de la actividad correspondiente al Poder Ejecu... more La Administración Pública es el contenido esencial de la actividad correspondiente al Poder Ejecutivo, y se refiere a las actividades de gestión, que el titular de la misma desempeña sobre los bienes del Estado para suministrarlos de forma inmediata y permanente, a la satisfacción de las necesidades públicas y lograr con ello el bien general; dicha atribución tiende a la realización de un servicio público, y se somete al marco jurídico especializado que norma su ejercicio y se concretiza mediante la emisión y realización del contenido de actos administrativos emitidos exprofeso.

Journal of Strength and Conditioning Research, 2002

The object of this study was to examine changes in muscular strength, power, and resting hormonal... more The object of this study was to examine changes in muscular strength, power, and resting hormonal concentrations during 6 weeks of detraining (DTR) in recreationally strengthtrained men. Each subject was randomly assigned to either a DTR (n ϭ 9) or resistance training (RT; n ϭ 7) group after being matched for strength, body size, and training experience. Muscular strength and power testing, anthropometry, and blood sampling were performed before the experimental period (T1), after 3 weeks (T2), and after the 6-week experimental period (T3). One-repetition maximum (1RM) shoulder and bench press increased in RT at T3 (p Յ 0.05), whereas no significant changes were observed in DTR. Peak power output and mean power output significantly decreased (9 and 10%) in DTR at T2. Peak torque of the elbow flexors at 90Њ did not change in the RT group but did significantly decrease by 11.9% at T3 compared with T1 in the DTR group. Vertical jump height increased in RT at T2 but did not change in DTR. Neither group displayed any changes in 1RM squat, body mass, percent body fat, or resting concentrations of growth hormone, follicle-stimulating hormone, luteinizing hormone, sex hormone-binding globulin, testosterone, cortisol, or adrenocorticotropin. These data demonstrate that 6 weeks of resistance DTR in recreationally trained men affects power more than it does strength without any accompanying changes in resting hormonal concentrations. For the recreational weight trainer, losses in strength over 6 weeks are less of a concern compared with anaerobic power and upper arm isometric force production. Anaerobic power exercise with a high metabolic component coming from glycolysis might be of importance for reducing the impact of DTR on Wingate power performances. A minimal maintenance training program is recommended for the recreational lifter to offset any reductions in performance. . Detraining produces minimal changes in physical performance and hormonal variables in recreationally strength-trained men.

Objective: Very low-carbohydrate diets are widely used for weight loss yet few controlled studies... more Objective: Very low-carbohydrate diets are widely used for weight loss yet few controlled studies have determined how these diets impact cardiovascular risk factors compared to more traditional low-fat weight loss diets. The primary purpose of this study was to compare a very low-carbohydrate and a low-fat diet on fasting blood lipids, LDL subclasses, postprandial lipemia, and insulin resistance in overweight and obese women.

Medicine and Science in Sports and Exercise, 2002

Very low-carbohydrate (ketogenic) diets are popular yet little is known regarding the effects on ... more Very low-carbohydrate (ketogenic) diets are popular yet little is known regarding the effects on serum biomarkers for cardiovascular disease (CVD). This study examined the effects of a 6-wk ketogenic diet on fasting and postprandial serum biomarkers in 20 normal-weight, normolipidemic men. Twelve men switched from their habitual diet (17% protein, 47% carbohydrate and 32% fat) to a ketogenic diet (30% protein, 8% carbohydrate and 61% fat) and eight control subjects consumed their habitual diet for 6 wk. Fasting blood lipids, insulin, LDL particle size, oxidized LDL and postprandial triacylglycerol (TAG) and insulin responses to a fat-rich meal were determined before and after treatment. There were significant decreases in fasting serum TAG (Ϫ33%), postprandial lipemia after a fat-rich meal (Ϫ29%), and fasting serum insulin concentrations (Ϫ34%) after men consumed the ketogenic diet. Fasting serum total and LDL cholesterol and oxidized LDL were unaffected and HDL cholesterol tended to increase with the ketogenic diet (ϩ11.5%; P ϭ 0.066). In subjects with a predominance of small LDL particles pattern B, there were significant increases in mean and peak LDL particle diameter and the percentage of LDL-1 after the ketogenic diet. There were no significant changes in blood lipids in the control group. To our knowledge this is the first study to document the effects of a ketogenic diet on fasting and postprandial CVD biomarkers independent of weight loss. The results suggest that a short-term ketogenic diet does not have a deleterious effect on CVD risk profile and may improve the lipid disorders characteristic of atherogenic dyslipidemia.

Journal of Strength and Conditioning Research, 2004

Hypoenergetic very low-carbohydrate and low-fat diets are both commonly used for short-term weigh... more Hypoenergetic very low-carbohydrate and low-fat diets are both commonly used for short-term weight loss; however, few studies have directly compared their effect on blood lipids, with no studies to our knowledge comparing postprandial lipemia, an important independently identified cardiovascular risk factor. The primary purpose of this study was to compare the effects of a very low-carbohydrate and a low-fat diet on fasting blood lipids and postprandial lipemia in overweight men. In a balanced, randomized, crossover design, overweight men (n ϭ 15; body fat Ͼ25%; BMI, 34 kg/m 2 ) consumed 2 experimental diets for 2 consecutive 6-wk periods. One was a very low-carbohydrate (Ͻ10% energy as carbohydrate) diet and the other a low-fat (Ͻ30% energy as fat) diet. Blood was drawn from fasting subjects on separate days and an oral fat tolerance test was performed at baseline, after the very low-carbohydrate diet period, and after the low-fat diet period. Both diets had the same effect on serum total cholesterol, serum insulin, and homeostasis model analysis-insulin resistance (HOMA-IR). Neither diet affected serum HDL cholesterol (HDL-C) or oxidized LDL (oxLDL) concentrations. Serum LDL cholesterol (LDL-C) was reduced (P Ͻ 0.05) only by the low-fat diet (Ϫ18%). Fasting serum triacylglycerol (TAG), the TAG/HDL-C ratio, and glucose were significantly reduced only by the very low-carbohydrate diet (Ϫ44, -42, and -6%, respectively). Postprandial lipemia was significantly reduced when the men consumed both diets compared with baseline, but the reduction was significantly greater after intake of the very low-carbohydrate diet. Mean and peak LDL particle size increased only after the very low-carbohydrate diet. The short-term hypoenergetic low-fat diet was more effective at lowering serum LDL-C, but the very low-carbohydrate diet was more effective at improving characteristics of the metabolic syndrome as shown by a decrease in fasting serum TAG, the TAG/HDL-C ratio, postprandial lipemia, serum glucose, an increase in LDL particle size, and also greater weight loss (P Ͻ 0.05). J. Nutr. 134: 880 -885, 2004.

Antimicrobial Agents and Chemotherapy, 2004

Science, 1997

5ites along run-of-r~\-er ~mpoiundments (n = 13). the mean sarn~3le scores tor tlie tlrst DCX axl... more 5ites along run-of-r~\-er ~mpoiundments (n = 13). the mean sarn~3le scores tor tlie tlrst DCX axls LliJ not d~ffer from thixe ot free-tlo~iiny sites (115.8 versus 1Q2.7, P = Q.c79i), <ugye.;t-~n g that tlorlst~c recover\-may occur.

Proceedings of The National Academy of Sciences, 1997

Our recent data show that in cardiac myocytes polyunsaturated fatty acids (PUFAs) are antiarrhyth... more Our recent data show that in cardiac myocytes polyunsaturated fatty acids (PUFAs) are antiarrhythmic. They reduce I(Na), shorten the action potential, shift the threshold for excitation to more positive potentials, and prolong the relative refractory period. In this study we use patch-clamp techniques in whole-cell mode and confocal Ca2+ imaging to examine the effects of PUFAs on the voltage-gated L-type Ca2+ current (I(Ca,L)), elementary sarcoplasmic reticulum Ca2+-release events (Ca2+-sparks), and [Ca2+]i transients in isolated rat ventricular myocytes. Extracellular application of eicosapentaenoic acid (EPA; C20:5 n - 3) produced a prompt and reversible concentration-dependent suppression of I(Ca,L). The concentration of EPA to produce 50% inhibition of I(Ca) was 0.8 microM in neonatal rat heart cells and 2.1 microM in adult ventricular myocytes. While the EPA induced suppression of I(Ca,L), it did not significantly alter the shape of the current-voltage relation but did produce a small, but significant, negative shift of the steady-state inactivation curve. The inhibition of I(Ca,L) was voltage- and time-dependent, but not use- or frequency-dependent. Other PUFAs, such as docosahexaenoic acid, arachidonic acid, linolenic acid, linoleic acid, conjugated linoleic acid, and eicosatetraynoic acid had similar effects on I(Ca,L) as EPA. All-trans-retinoic acid, which had been shown to suppress induced arrhythmogenic activity in rat heart cells, also produced a significant inhibition of I(Ca,L). The saturated stearic acid and the monounsaturated oleic acid had no effect on I(Ca,L). Because both I(Ca,L) and sarcoplasmic reticulum Ca2+-release underlie many cardiac arrhythmias, we examined the effects of EPA on I(Ca,L) and Ca2+-sparks. While EPA suppressed both, it did not change the temporal or spatial character of the Ca2+-sparks, nor did it alter the ability of I(Ca,L) to trigger Ca2+-sparks. We conclude that PUFAs may act as antiarrhythmic agents in vivo in normal and Ca2+-overloaded cells principally because they reduce Ca2+ entry by blocking I(Ca,L). Furthermore, PUFAs act directly to decrease I(Na) and I(Ca,L), but indirectly to reduce the [Ca2+]i transients and [Ca2+]i-activated membrane current. Although a negative inotropic action is associated with application of PUFAs, it is clear that by reducing I(Ca,L), I(Na) and Ca2+-sparks, PUFAs can reduce spontaneous extrasystoles in the heart. The mechanisms by which PUFAs act are discussed.

La Administración Pública es el contenido esencial de la actividad correspondiente al Poder Ejecu... more La Administración Pública es el contenido esencial de la actividad correspondiente al Poder Ejecutivo, y se refiere a las actividades de gestión, que el titular de la misma desempeña sobre los bienes del Estado para suministrarlos de forma inmediata y permanente, a la satisfacción de las necesidades públicas y lograr con ello el bien general; dicha atribución tiende a la realización de un servicio público, y se somete al marco jurídico especializado que norma su ejercicio y se concretiza mediante la emisión y realización del contenido de actos administrativos emitidos exprofeso.