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1.
Exp Gerontol ; 171: 112030, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36423855

RESUMEN

INTRODUCTION: Faced with lockdowns, it was mandatory the development of supervised home-based RT protocols to keep patients with chronic kidney disease engaged in programs. Nonetheless, there is a lack of scientific literature regarding its effects on patients. PURPOSE: To investigate the effects of a supervised home-based progressive resistance training program on functional performance, bone mineral density, renal function, endothelial health, inflammation, glycemic homeostasis, metabolism, redox balance, and the modulation of exerkines in patients with CKD in stage 2. METHODS: Patients (n = 31) were randomized and allocated into the control group (CTL; n = 15; 58.07 ± 5.22 yrs) or resistance training group (RT; n = 16; 57.94 ± 2.74 yrs). RT group performed 22 weeks of supervised progressive home-based resistance exercises. Bone mineral density, anthropometric measurements, and functional performance were assessed. Venous blood samples were collected at baseline and after the intervention for the analysis of markers of renal function, endothelial health, inflammation, glycemic homeostasis, metabolism, and redox balance. RESULTS: Twenty-two weeks of home-based RT were effective in improving (P < 0.05) functional performance, bone mineral density, uremic profile, ADMA, inflammatory markers, the Klotho-FGF23 axis, glycemic homeostasis markers, and exerkines. These improvements were accompanied by higher concentrations of exerkines and anti-inflammatory cytokines. RT group displayed a decrease in cases of osteopenia after the intervention (RT: 50 % vs. CTL: 86.7 %; X2 = 4.763; P = 0.029). CONCLUSION: Results provide new evidence that supervised home-based progressive RT may be a relevant intervention to attenuate the progression of CKD and improve functional capacity, bone mineral density, and the immunometabolic profile. These improvements are associated with positive modulation of several exerkines.


Asunto(s)
Insuficiencia Renal Crónica , Entrenamiento de Fuerza , Humanos , Entrenamiento de Fuerza/métodos , Insuficiencia Renal Crónica/terapia , Ejercicio Físico , Terapia por Ejercicio , Densidad Ósea , Inflamación
2.
Sports (Basel) ; 12(1)2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38251280

RESUMEN

The "zero point" method allows for lower intensities for an exercise session without impairing the total training volume. This study aimed to compare the effects of the "zero point" versus the traditional method on muscle responses and muscle damage in trained men. Fifteen experienced men (age: 27.7 ± 6.4 years; body mass: 78.4 ± 11.4 kg; height: 174.8 ± 4.9 cm; experience: 5.86 ± 4.7 years; relative bench press strength: 1.38 ± 0.17 kg·kg-1) were subjected to two exercise protocols in a randomized order and separated by a week. The traditional and "zero point" methods were applied in the bench press, with loads of 70% and 50% of one repetition maximum (1RM), respectively, for 10 sets until concentric failure, with 3-min intervals between sets. The zero point method displayed a higher number of repetitions and time under tension than the traditional method, with no difference in the total training volume, echo intensity, algometry, lactate, and myoglobin. For the muscle thickness, no differences between the groups were presented, except for the deltoid muscle thickness, in which a higher post-training volume was observed compared to traditional training. The "zero point" method increases the demand on the deltoid muscles in the bench press exercise, but not on the pectoralis and triceps brachii.

3.
Front Immunol ; 13: 1006076, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36248863

RESUMEN

Background: The global burden of persistent COVID-19 in hemodialysis (HD) patients is a worrisome scenario worth of investigation for the critical care of chronic kidney disease (CKD). We performed an exploratory post-hoc study from the trial U1111-1237-8231 with two specific aims: i) to investigate the prevalence of COVID-19 infection and long COVID symptoms from our Cohort of 178 Brazilians HD patients. ii) to identify whether baseline characteristics should predict long COVID in this sample. Methods: 247 community-dwelling older (>60 years) patients (Men and women) undergoing HD (glomerular filtration rate < 15 mL/min/1.73m2) with arteriovenous fistula volunteered for this study. All patients presented hypertension and diabetes. Patients were divided in two groups: without long-COVID and with long-COVID. Body composition, handgrip strength, functional performance, iron metabolism, phosphate, and inflammatory profile were assessed. Patients were screened for 11-months after COVID-19 infection. Results were considered significant at P < 0.05. Results: We found that more than 85% of the COVID-19 infected patients presented a severe condition during the infection. In our sample, the mortality rate over 11-month follow was relatively low (8.4%) when compared to worldwide (approximately 36%). Long COVID was highly prevalent in COVID-19 survivors representing more than 80% of all cases. Phosphate and IL-10 were higher in the long COVID group, but only phosphate higher than 5.35 mg/dL appears to present an increased prevalence of long COVID, dyspnea, and fatigue. Conclusion: There was a high prevalence of COVID-19 infection and long COVID in HD patients from the Brazilian trial 'U1111-1237-8231'. HD clinics should be aware with phosphate range in HD patients as a possible target for adverse post-COVID events.


Asunto(s)
COVID-19 , Brasil/epidemiología , COVID-19/complicaciones , COVID-19/epidemiología , Femenino , Fuerza de la Mano , Humanos , Interleucina-10 , Hierro , Masculino , Fosfatos , Diálisis Renal/efectos adversos , Diálisis Renal/métodos , Síndrome Post Agudo de COVID-19
4.
Int J Sports Med ; 43(1): 29-33, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34256387

RESUMEN

Lower SIRT1 and insulin resistance are associated with accelerated telomere shortening. This study investigated whether the lifestyle of master athletes can attenuate these age-related changes and thereby slow aging. We compared insulin, SIRT1, and telomere length in highly trained male master athletes (n=52; aged 49.9±7.2 yrs) and age-matched non-athletes (n=19; aged 47.3±8.9 yrs). This is a cross-sectional study, in which all data were collected in one visit. Overnight fasted SIRT1 and insulin levels in whole blood were assessed using commercial kits. Relative telomere length was determined in leukocytes through qPCR analyses. Master athletes had higher SIRT1, lower insulin, and longer telomere length than age-matched non-athletes (p<0.05 for all). Insulin was inversely associated with SIRT1 (r=-0.38; p=0.001). Telomere length correlated positively with SIRT1 (r=0.65; p=0.001), whereas telomere length and insulin were not correlated (r=0.03; p=0.87). In conclusion, master athletes have higher SIRT1, lower insulin, and longer telomeres than age-matched non-athletes. Furthermore, SIRT1 was negatively associated with insulin and positively associated with telomere length. These findings suggest that in this sample of middle-aged participants reduced insulin, increased SIRT1 activity, and attenuation of biological aging are connected.


Asunto(s)
Atletas , Insulina/sangre , Longevidad , Sirtuina 1 , Telómero/ultraestructura , Adulto , Envejecimiento , Estudios Transversales , Humanos , Leucocitos , Masculino , Persona de Mediana Edad , Sirtuina 1/genética
5.
J Strength Cond Res ; 36(6): 1591-1595, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32639377

RESUMEN

ABSTRACT: Neto, SLdA, Herrera, JJB, Rosa, TS, de Almeida, SS, Silva, GCB, Ferreira, CES, dos Santos, MAP, Silvino, VO, de Melo, GF. Interaction between ACTN3 (R577X), ACE (I/D), and BDKRB2 (-9/+9) polymorphisms and endurance phenotypes in Brazilian long-distance swimmers. J Strength Cond Res 36(6): 1591-1595, 2022-This study investigated the interactions between the polymorphisms ACTN3 (R577X), ACE (I/D), and BDKRB2 (-9/+9) and their association with endurance phenotypes in Brazilian long-distance swimmers. Twenty-six volunteers (aged 18-30 years) were divided into 2 groups as follows: 19 subelite athletes formed the pool swimming experts (PSE: 400-1500 m) group and 7 elite athletes the open water swimming experts (OWSE: 5-25 km) group. ACTN3 (R577X), ACE (I/D), and BDKRB2 (-9/+9) polymorphisms were genotyped through polymerase chain reaction. A nonathletes control (CON) group derived from studies with the Brazilian population was created. Hardy-Weinberg equilibrium (X2) was observed in all groups. The total genotype score (TGS) associated with endurance phenotypes was used in this study. A significance level was established at p ≤ 0.05. PSE and CON groups had very similar genotyping distribution. The OWSE group had a greater frequency for the genotypes XX (57.1%), ID (57.1%), and the alleles X (71.4%) and I (57.2%) than CON and PSE groups (XX = 21.1 and 21.1%; ID = 47.1 and 52.6% [p > 0.05]; X = 44.0 and 42.1%; I = 45.3 and 42.1%, respectively). Considering BDKRB2, OWSE and PSE groups had a greater frequency of +9/+9 than the CON group (42.9% and 31.6 vs. 27.5%, respectively). Although the expected genotypic distribution was not verified among athletes, the TGS revealed small supremacy of 3-5 typical alleles in the OWSE group (54.8 ± 26.7%) compared with the PSE group (41.2 ± 17.8%) (p = 0.072; confidence interval = 95%; effect size = 0.95). The OWSE group seem to have benefited from the best genotype profile verified for ACTN3 and ACE. However, the results of this work should be approached with caution because of the small number of athletes and polymorphisms assessed.


Asunto(s)
Actinina , Peptidil-Dipeptidasa A , Actinina/genética , Brasil , Genotipo , Humanos , Peptidil-Dipeptidasa A/genética , Fenotipo , Polimorfismo Genético
6.
Oxid Med Cell Longev ; 2021: 3683796, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34621463

RESUMEN

Aerobic training (AT) promotes several health benefits that may attenuate the progression of obesity associated diabetes. Since AT is an important nitric oxide (NO-) inducer mediating kidney-healthy phenotype, the present study is aimed at investigating the effects of AT on metabolic parameters, morphological, redox balance, inflammatory profile, and vasoactive peptides in the kidney of obese-diabetic Zucker rats receiving L-NAME (N(omega)-nitro-L-arginine methyl ester). Forty male Zucker rats (6 wk old) were assigned into four groups (n = 10, each): sedentary lean rats (CTL-Lean), sedentary obese rats (CTL-Obese), AT trained obese rats without blocking nitric oxide synthase (NOS) (Obese+AT), and obese-trained with NOS block (Obese+AT+L-NAME). AT groups ran 60 min in the maximal lactate steady state (MLSS), five days/wk/8 wk. Obese+AT rats improved glycemic homeostasis, SBP, aerobic capacity, renal mitochondria integrity, redox balance, inflammatory profile (e.g., TNF-α, CRP, IL-10, IL-4, and IL-17a), and molecules related to renal NO- metabolism (klotho/FGF23 axis, vasoactive peptides, renal histology, and reduced proteinuria). However, none of these positive outcomes were observed in CTL-Obese and Obese+AT+L-NAME (p < 0.0001) groups. Although Obese+AT+L-NAME lowered BP (compared with CTL-Obese; p < 0.0001), renal damage was observed after AT intervention. Furthermore, AT training under conditions of low NO- concentration increased signaling pathways associated with ACE-2/ANG1-7/MASr. We conclude that AT represents an important nonpharmacological intervention to improve kidney function in obese Zucker rats. However, these renal and metabolic benefits promoted by AT are dependent on NO- bioavailability and its underlying regulatory mechanisms.


Asunto(s)
Riñón/metabolismo , Óxido Nítrico/metabolismo , Obesidad/metabolismo , Condicionamiento Físico Animal , Transducción de Señal/efectos de los fármacos , Animales , Disponibilidad Biológica , Glucemia/metabolismo , Inhibidores Enzimáticos/farmacología , Masculino , Mitocondrias/metabolismo , Modelos Animales , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Oxidación-Reducción/efectos de los fármacos , Ratas , Ratas Zucker , Especies Reactivas de Oxígeno/metabolismo
7.
Exp Gerontol ; 146: 111212, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33387607

RESUMEN

The aim of this systematic review and meta-analysis was 1) to assess whether master athletes have longer telomeres than age-matched non-athletes and 2) discuss possible underlying mechanisms underlying telomere length preservation in master athletes. A literature search was performed in PubMed, Web of Science, Scopus and SPORTDiscus up to August 2020. Only original articles published in peer-reviewed journals that compared telomere length between master athletes and aged-matched non-athletes were included. Eleven studies fulfilled eligibility criteria and were included in the final analysis. Overall, 240 master athletes (51.9±7.5 years) and 209 age-matched non-athletes (50.1±9.1 years) were analyzed. Master athletes had been participating in high-level competitions for approximately 16.6 years. Pooled analyses revealed that master athletes had longer telomeres than aged-matched non-athletes (SMD=0.89; 95% CI=0.45 to 1.33; p<0.001). Master athletes showed lower pro-oxidant damage (SMD=0.59; 95% CI=0.26 to 0.91; p<0.001) and higher antioxidant capacity (SMD=-0.46; 95% CI=-0.89 to -0.03; p=0.04) than age-matched non-athletes. Further, greater telomere length in master athletes is associated with lower oxidative stress and chronic inflammation, and enhanced shelterin protein expression and telomerase activity. In conclusion, 1) master athletes have longer telomeres than age-matched non-athletes, which may be the result of 2) lower levels of oxidative stress and chronic inflammation, and elevated shelterin expression and telomerase activity.


Asunto(s)
Envejecimiento , Telómero , Anciano , Atletas , Humanos , Estrés Oxidativo
8.
J Appl Physiol (1985) ; 130(2): 508-516, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33242299

RESUMEN

This study compared the effectiveness of dynamic resistance training (DRT) versus isometric RT (IRT) on osteogenesis and hormonal mechanisms involved in maintenance hemodialysis (MHD) patients. One hundred and ninety-three MHD patients were randomized into three groups: control (CTL) (n = 60), DRT (n = 66), and IRT (n = 67). A first visit was required for an anamnesis to evaluate the number of medications, biochemical, and anthropometric measurements (dialysis adequacy, creatinine, urea, body mass, height, and body mass index). Grip strength, bone mineral density (BMD), and renal-bone markers were assessed pre- and postprotocol. The DRT and IRT training was 6 mo with a frequency of three times per week, on alternate days. Each training session consisted of three sets of 8 to 12 repetitions at lower and moderate intensities. Both training sessions were prescribed approximately 1 h prior to dialysis. Statistical significances were adopted with P < 0.05. There was a greater dropout in the IRT group (24%) as compared with the DRT group (14%), which in turn had less adverse clinical effects (67%, 24%, and 61% for CTL, DRT, and IRT, respectively). DRT promoted gains in BMD in different body locations, in addition to increasing pro-osteogenic factors (Klotho and calcitriol) and reducing those related to bone loss, such as sclerostin, FGF23, and PTH. There was an improvement in Ca × PO43 for DRT, whereas these benefits did not occur in the IRT group (P < 0.05). These novel findings suggest that the DRT generates biopositive adaptations in bone tissue in MHD and can be used as a nonpharmacological strategy to improve BMD.NEW & NOTEWORTHY This study shows, for the first time, the effect of dynamic and isometric resistance training on bone mineral density in hemodialysis patients, providing a new understanding of the possible participation of the sclerostin/FGF23/Klotho axis, vitD, PTH, and calcium × phosphate product in this process. However, isometric resistance training may not be sufficient to induce these benefits. Therefore, this study supports the potential therapeutic role of dynamic resistance training counteracting chronic kidney disease-mineral and bone disorder.


Asunto(s)
Enfermedades Óseas Metabólicas , Entrenamiento de Fuerza , Densidad Ósea , Huesos , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos , Humanos , Diálisis Renal
9.
J Strength Cond Res ; 35(6): 1693-1699, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30640301

RESUMEN

ABSTRACT: Aguiar, SS, Rosa, TS, Sousa, CV, Santos, PA, Barbosa, LP, Deus, LA, Rosa, EC, Andrade, RV, and Simões, HG. Influence of body fat on oxidative stress and telomere length of master athletes. J Strength Cond Res 35(6): 1693-1699, 2021-The present investigation analyzed the role of body fat and training history on biological aging of master athletes by comparing and verifying the relationships between markers of adiposity, oxidative balance, and telomere length (TL) in middle-aged runners and untrained individuals. Master athletes (sprinters and endurance runners, n = 21; 51.62 ± 8.19 years) and untrained age-matched controls (n = 11; 45.41 ± 10.34 years) had blood samples collected for biochemical and biomolecular analyzes. Pro-oxidant and antioxidant measures as well as DNA extraction were performed using commercial kits. Relative TL (T/S) was determined in leukocytes through quantitative polymerase chain reaction analyses. Master athletes had lower body fat and longer TL than untrained controls (body fat: 12.21 ± 4.14% vs. 26.03 ± 4.29%; TL: 1.10 ± 0.84 vs. 0.56 ± 0.56 T/S; p < 0.05). Furthermore, master athletes also showed a better oxidative balance than untrained controls (p < 0.05). A negative correlation was observed between TL and body fat (r = -0.471; p = 0.007), and conicity index (r = -0.407; p = 0.021), catalase activity (r = -0.569; p = 0.001), and CAT/TBARS ratio (r = -0.463; p = 0.008) for the whole sample. In conclusion, master athletes have longer TL, better oxidative profile, and lower body fat than untrained individuals. Moreover, for this middle-aged sample, body fat was inversely correlated with both TL and markers of oxidative balance, demonstrating the key role of adiposity in biological aging.


Asunto(s)
Atletas , Telómero , Tejido Adiposo , Envejecimiento , Humanos , Persona de Mediana Edad , Estrés Oxidativo , Telómero/genética
11.
Int J Exerc Sci ; 13(3): 597-606, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32509119

RESUMEN

The objective of this study was to compare the effects of very high supervision (VHS-RT) versus high supervision (HS-RT) ratio resistance training (RT) on irisin, brain-derived neurotrophic factor (BNDF), muscle strength, functional capacity, and body composition in elderly women. Participants performed daily undulating periodized RT over 16 weeks with two different supervision ratios: VHS-RT at 1:2 (supervisor/subject) or HS-RT at 1:5. Serum was used to analyze brain derived neurotropic factor (BDNF) and irisin by enzyme-linked immunosorbent assay (ELISA). Body composition was evaluated by dual-energy X-ray absorptiometry, while functional capacity was evaluated using the Six-minute walk test, and Timed Up and Go (TUG). One- repetition maximum (1RM) was determined for bench press and 45° leg press exercises. For both groups, no differences between baseline and post-training were identified for irisin and lean mass (p > 0.05). Both groups improved bench press 1-RM, 45° leg press 1-RM, and TUG (p < 0.05). The VHS-RT group displayed higher effect sizes for 1-RM tests. Moreover, only VHS-RT group reduced body fat and body fat percentage (p < 0.05). In contrast, the HS-RT increased BDNF (p < 0.01). In this sense, RT enhances muscle strength and functional capacity in elderly women independent of supervision ratio. A greater supervision ratio during RT may induce more improvements in muscle strength, and body composition than lower supervision ratio during RT.

12.
Exp Gerontol ; 117: 113-118, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30481549

RESUMEN

Leukocyte telomere length (LTL), a biological marker of aging that is associated with age-related diseases, is longer in master endurance runners (ER) than age-matched controls, but the underlying mechanisms are poorly investigated. The LTL, nitric oxide (NO), and redox balance of ER master runners were analyzed and compared to untrained middle-aged and young adults. We hypothesized that NO and redox balance at baseline would be related to longer LTL in ER athletes. Participants (n = 38) were long-term ER runners (n = 10; 51.6 ±â€¯5.2 yrs.; 28.4 ±â€¯9.4 yrs. of experience) and untrained age-matched (n = 17; 46.6 ±â€¯7.1 yrs) and young controls (n = 11; 21.8 ±â€¯4.0 yrs). Volunteers were assessed for anamnesis, anthropometrics, and blood sampling. Measurements of pro-and anti-oxidant status and DNA extraction were performed using commercial kits. Relative LTL was determined with qPCR analyses (T/S). While the middle-aged controls had shorter LTL than the young group, no difference was observed between ER athletes and young participants. A large effect size between the LTL of ER athletes and middle-aged controls (d = 0.85) was also observed. The ER athletes and untrained young group had better redox balance according to antioxidant/pro-oxidant ratios compared to middle-aged untrained participants, which also had lower values for redox parameters (TEAC/TBARS, SOD/TBARS, and CAT/TBARS; all p < 0.05). Furthermore, the NO level of ER athletes (175.2 ±â€¯31.9 µM) was higher (p < 0.05) than middle-aged controls (67.2 ±â€¯23.3 µM) and young participants (129.2 ±â€¯17.3 µM), with a significant correlation with LTL (r = 0.766; p = 0.02). In conclusion, ER runners have longer LTL than age-matched controls, which in turn may be related to better NO bioavailability and redox balance status.


Asunto(s)
Envejecimiento/fisiología , Óxido Nítrico/fisiología , Carrera/fisiología , Homeostasis del Telómero/fisiología , Adulto , Anciano , Envejecimiento/genética , Atletas , Composición Corporal/fisiología , Estudios de Casos y Controles , Humanos , Leucocitos/metabolismo , Peroxidación de Lípido/fisiología , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Estrés Oxidativo/fisiología , Resistencia Física/fisiología
13.
J Strength Cond Res ; 32(10): 2971-2977, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29384998

RESUMEN

Souza, LR, Vicente, JB, Melo, GR, Moraes, VC, Olher, RR, Sousa, IC, Peruchi, LH, Neves, RV, Rosa, TS, Ferreira, AP, and Moraes, MR. Acute hypotension after moderate-intensity handgrip exercise in hypertensive elderly people. J Strength Cond Res 32(10): 2971-2977, 2018-Isometric handgrip (IHG) training is effective in reducing blood pressure (BP), but little is known about the occurrence of acute hypotension by postisometric exercise hypotension (PIEH) and the underlying mechanisms. Ten sedentary hypertensive elderly people (7 women and 3 men) individuals, with a mean age of 73.2 ± 2.2 years and systolic BP (SBP) of 135.1 ± 6.5, were included; they were hypertensive for 13.2 ± 3.1 years and were receiving medications. These patients underwent 2 experimental sessions of isometric exercise using a portable hydraulic handgrip dynamometer: (a) sham session with 3% of maximal voluntary isometric contraction (MVIC) and (b) experimental isometric session with 30% MVIC, completing a total of 8 sets of 1-minute contraction and 1-minute rest-pause (overload of work = 51.7 kgf·min). Blood pressure and heart rate were evaluated at rest and 1, 5, 10, 15, 30, 45, and 60 minutes postexercise. Blood lactate (Lac) and salivary nitric oxide (NO) were collected at rest, 0, 30, and 60 minutes postexercise. The SBP presented a reduction as of the tenth minute postexercise to session 30% MVIC (Δ = -14.4 at -18.7 mm Hg, p < 0.05). At 60-minute postexercise, the SBP was 30% lower vs. 3% MVIC (-20.2 mm Hg, p = 0.006). There were no differences for the other cardiovascular parameters and vasoactive substances for both sessions (p > 0.05). These results demonstrated that the IHG exercise with a higher overload of work induced PIEH in hypertensive elderly people, but there was no association with Lac and NO. Therefore, this IHG model with easy execution, quick adherence, short duration, and a portable equipment can be an excellent adjuvant strategy for the control and prevention of hypertension.


Asunto(s)
Ejercicio Físico , Fuerza de la Mano , Hipertensión/terapia , Hipotensión/etiología , Anciano , Presión Sanguínea , Determinación de la Presión Sanguínea , Sistema Cardiovascular/fisiopatología , Femenino , Frecuencia Cardíaca , Humanos , Hipertensión/fisiopatología , Contracción Isométrica , Ácido Láctico/sangre , Masculino , Dinamómetro de Fuerza Muscular , Óxido Nítrico/análisis , Descanso , Saliva/química , Factores de Tiempo
14.
Front Physiol ; 7: 122, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27148063

RESUMEN

Severe obesity affects metabolism with potential to influence the lactate and glycemic response to different exercise intensities in untrained and trained rats. Here we evaluated metabolic thresholds and maximal aerobic capacity in rats with severe obesity and lean counterparts at pre- and post-training. Zucker rats (obese: n = 10, lean: n = 10) were submitted to constant treadmill bouts, to determine the maximal lactate steady state, and an incremental treadmill test, to determine the lactate threshold, glycemic threshold and maximal velocity at pre and post 8 weeks of treadmill training. Velocities of the lactate threshold and glycemic threshold agreed with the maximal lactate steady state velocity on most comparisons. The maximal lactate steady state velocity occurred at higher percentage of the maximal velocity in Zucker rats at pre-training than the percentage commonly reported and used for training prescription for other rat strains (i.e., 60%) (obese = 78 ± 9% and lean = 68 ± 5%, P < 0.05 vs. 60%). The maximal lactate steady state velocity and maximal velocity were lower in the obese group at pre-training (P < 0.05 vs. lean), increased in both groups at post-training (P < 0.05 vs. pre), but were still lower in the obese group at post-training (P < 0.05 vs. lean). Training-induced increase in maximal lactate steady state, lactate threshold and glycemic threshold velocities was similar between groups (P > 0.05), whereas increase in maximal velocity was greater in the obese group (P < 0.05 vs. lean). In conclusion, lactate threshold, glycemic threshold and maximal lactate steady state occurred at similar exercise intensity in Zucker rats at pre- and post-training. Severe obesity shifted metabolic thresholds to higher exercise intensity at pre-training, but did not attenuate submaximal and maximal aerobic training adaptations.

15.
J Clin Transl Res ; 2(2): 63-69, 2016 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-30873463

RESUMEN

BACKGROUND AND AIM: Rapid weight loss (RWL) is extensively practiced by combat sports athletes, including Mixed Martial Arts (MMA), but its effects on performance are not well established with different magnitudes of RWL, including those higher than 5% of total body weight. The aim of the present study was to follow MMA athletes during RWL with subsequent weight regain to evaluate the responses of isometric strength, power, cognition and salivary nitrite ( NO 2 - ) content. METHODS: Two professional male MMA fighters, same age, competing in the same weight category underwent two magnitudes of RWL before a simulated competition period. Anthropometric measures, records of nutritional status, training, voluntary dehydration strategies, salivary samples, cognition response, isometric strength and muscular power were obtained: (I) 7 days before combat, (II) at the weigh-in moment, and (III) in the combat day. RESULTS AND CONCLUSIONS: Athlete 1 lost 7.2 kg (9.1% of total bodyweight) and Athlete 2 lost 4.0 kg (5.3% of total bodyweight). Athlete 1 had a lower and misbalanced caloric ingestion (708 ± 428 kcal), ingested 6 L of water during the first 5 days of RWL, underwent 2 days of fasting, water and sodium restriction before weigh-in. Athlete 2 was supervised by a nutritionist, had a balanced diet (1600 ± 0 kcal), ingested 2 L of water during the first 6 days of RWL, underwent only 1 day of fasting and water restriction, and did not restrict sodium. As expected, there was a negative effect of RWL in the evaluated parameters at the weigh-in moment, while in the combat day, salivary NO 2 - ) content. METHODS: Two professional male MMA fighters, same age, competing in the same weight category underwent two magnitudes of RWL before a simulated competition period. Anthropometric measures, records of nutritional status, training, voluntary dehydration strategies, salivary samples, cognition response, isometric strength and muscular power were obtained: (I) 7 days before combat, (II) at the weigh-in moment, and (III) in the combat day. RESULTS AND CONCLUSIONS: Athlete 1 lost 7.2 kg (9.1% of total bodyweight) and Athlete 2 lost 4.0 kg (5.3% of total bodyweight). Athlete 1 had a lower and misbalanced caloric ingestion (708 ± 428 kcal), ingested 6 L of water during the first 5 days of RWL, underwent 2 days of fasting, water and sodium restriction before weigh-in. Athlete 2 was supervised by a nutritionist, had a balanced diet (1600 ± 0 kcal), ingested 2 L of water during the first 6 days of RWL, underwent only 1 day of fasting and water restriction, and did not restrict sodium. As expected, there was a negative effect of RWL in the evaluated parameters at the weigh-in moment, while in the combat day, salivary NO 2 - was not completely reestablished at baseline levels (decreased by 35.9% in Athlete 1 and, 25.2% in Athlete 2, as compared with 7 days before). The athlete who underwent a lower weight loss (5.3%) presented better recovery of cognition and upper limbs power on the combat day as compared with the athlete who lost 9.1% of body weight. Although we cannot precisely conclude, this case report led us to believe that the recovery period between weigh-in and competition may be insufficient for total reestablishment of salivary NO 2 - after RWL, and higher amounts of RWLhave negative impacts on average power and cognition when compared with lower RWL.Relevance for patients: Scientific aspects related with performance in MMA athletes brought to light the absence of studies investigating the recovery of isometric strength, power, cognition and salivary NO 2 - during RWL with subsequent weight regain. This study revealed that athletes from the same categories can adopt different magnitudes of weight loss, and that this procedure impacts several important measures, for example, the reduction of salivary NO 2 - is associated with the lower O2 transport capacity, decreasing muscle performance.

16.
J Strength Cond Res ; 26(4): 1122-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22126975

RESUMEN

To investigate the antihypertensive effects of conventional resistance exercise (RE) on the blood pressure (BP) of hypertensive subjects, 15 middle-aged (46 ± 3 years) hypertensive volunteers, deprived of antihypertensive medication (reaching 153 ± 6/93 ± 2 mm Hg systolic/diastolic BP after a 6-week medication washout period) were submitted to a 12-week conventional RE training program (3 sets of 12 repetitions at 60% 1 repetition maximum, 3 times a week on nonconsecutive days). Blood pressure was measured in all phases of the study (washout, training, detraining). Additionally, the plasma levels of several vasodilators or vasoconstrictors that potentially could be involved with the effects of RE on BP were evaluated pre- and posttraining. Conventional RE significantly reduced systolic, diastolic, and mean BP, respectively, by an average of 16 (p < 0.001), 12 (p < 0.01), and 13 mm Hg (p < 0.01) to prehypertensive values. There were no significant changes of vasoactive factors from the kallikrein-kinin or renin-angiotensin systems. After the RE training program, the BP values remained stable during a 4-week detraining period. Taken together, this study shows for the first time that conventional moderate-intensity RE alone is able to reduce the BP of stage 1 hypertensive subjects free of antihypertensive medication. Moreover, the benefits of BP reduction achieved with RE training remained unchanged for up to 4 weeks without exercise.


Asunto(s)
Presión Sanguínea/fisiología , Hipertensión/fisiopatología , Entrenamiento de Fuerza , Adulto , Antihipertensivos/administración & dosificación , Antihipertensivos/sangre , Electrocardiografía , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
17.
Exp Biol Med (Maywood) ; 236(10): 1180-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21930716

RESUMEN

The aim of the paper is to assess nitric oxide (NO) production during aerobic training and its role on the progression of diabetic nephropathy in rats. Induction of diabetes mellitus (DM) was achieved in adult male Wistar rats with streptozotocin. Half of the animals underwent training on a treadmill and the others (sedentary) stayed on a turned-off treadmill for the same period according to the following groups: sedentary control (CTL + SE); training control (CTL + EX); sedentary diabetic (DM + SE); and training diabetic (DM + EX) (n = 9 for all groups). The training on treadmill was carried out at a work rate of 16 m/min, 60 min/d, 5 d/week for eight weeks. Before and after the exercises, rats were placed in individual metabolic cages with standard chow and water ad libitum, for 24-h urine collection, followed by three hours' fasting blood sample withdrawal from the retro-orbital plexus, under anesthesia. Diabetic animals showed reduction of body weight, creatinine and urea depurations and NO excretion, increased blood glucose concentrations, albuminuria and thiobarbituric acid reactive substance (TBARS) excretion, when compared with the respective controls. All these alterations induced by DM were attenuated in the DM + EX versus DM + SE group. Analysis of insulin concentrations at the end of the protocol showed no significant change between the DM + SE and DM + EX groups. In conclusion, our data show that a routine physical exercise resulted in a better control of glycemia with an increased NO bioavailability and oxidative stress control, associated with an amelioration of renal function. We suggest aerobic training and the control of oxidative and nitrosative stress as useful non-pharmacological tools to delay the progression of diabetic nephropathy.


Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Nefropatías Diabéticas/fisiopatología , Óxido Nítrico/biosíntesis , Condicionamiento Físico Animal/fisiología , Albuminuria/metabolismo , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Nefropatías Diabéticas/prevención & control , Progresión de la Enfermedad , Insulina/sangre , Riñón/patología , Peroxidación de Lípido/fisiología , Masculino , Estrés Oxidativo/fisiología , Ratas , Ratas Wistar
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