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1.
Br J Clin Pharmacol ; 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31925809

RESUMO

AIMS: To determine the effects of statins on postprandial lipemia (PPL) and to study if exercise could enhance statin actions. METHODS: Ten hypercholesterolemic (blood cholesterol 204±36 mg·dL-1 ; LDL-c 129±32 36 mg·dL-1 ) overweight (BMI 30±4 kg·m-2 ), metabolic syndrome (MetS) individuals chronically medicated with statins (> 6 months) underwent 5-hr PPL tests in four occasions in a randomized order; a) substituting their habitual statin medication by placebo during 96 hours (PLAC trial), b) taking their habitual statin medicine (STA trial), c) placebo combined with a bout of intense aerobic exercise (EXER+PLAC trial) and d) combining exercise and statin medicine (EXER+STA trial). RESULTS: Before the fat meal, statin withdrawal (i.e., PLAC and EXER+PLAC) increased blood triglycerides (TG; 24%), LDL-c (31%) and total cholesterol (19%; all P<0.05) evidencing treatment compliance. After the meal, statin withdrawal increased 5-h postprandial TG (PPTG) compared to its matched trials (94% higher PLAC vs STA and 45% higher EXER+PLAC vs EXER+STA; P<0.05). EXER+PLAC trial did not lower PPTG below PLAC (i.e., incremental AUC of 609±152 vs 826±190 mg·dL-1 ·5 h; P=0.09). Neither adding exercise to statin resulted in larger reductions in PPTG (i.e., EXER+STA vs STA iAUC of 421±87 vs 421±84 mg·dL-1 ·5 h; P=0.99). CONCLUSION: In hypercholesteremic MetS individuals, chronic statin therapy blunts the elevations in TG after a fat meal (i.e., iAUC of PPTG) reducing the cardiovascular risk associated to their atherogenic dyslipidemia. However, a single bout of intense aerobic exercise before the high fat meal, does not reduce PPTG but neither interferes with the effects of statin treatment.

2.
PLoS One ; 14(12): e0225893, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31821339

RESUMO

High-intensity interval training (HIIT), is effective to improve cardiorespiratory fitness (CRF) and metabolic syndrome (MetS) components in adults. However, it is unclear if CRF and MetS components respond similarly in men and women after HIIT. For 16 weeks, 63 women (53±7 years) and 56 men (55±8 years) with MetS underwent a three day/week HIIT program. Bodyweight and composition, VO2MAX, surrogate parameters of CRF (Ventilatory threshold (VT), oxygen uptake efficiency slope (OUES) and VE/VCO2 slope), maximal rate of fat oxidation (MFO), and MetS components were assessed before and after training. All reported variables were analyzed by split-plot ANOVA looking for time by sex interactions. Before training men had higher absolute values of VO2MAX (58.6%), and MFO (24.6%), while lower body fat mass (10.5%) than women (all P<0.05). After normalization by fat-free mass (FFM), VO2MAX remained 16.6% higher in men (P<0.05), whereas differences in MFO disappeared (P = 0.292). After intervention VO2MAX (P<0.001), VO2 at VT (P<0.001), OUES (P<0.001), and VE/VCO2 slope (P<0.001) increased without differences by sex (P>0.05). After training MetS Z-score (P<0.001) improved without differences between men and women (P>0.05). From the MetS components, only blood pressure (P<0.001) and waist circumference (P<0.001) improved across time, without differences by sex. In both, women and men, changes in OUES (r = 0.685 and r = 0.445, respectively), and VO2 at VT (r = 0.378, and r = 0.445, respectively), correlated with VO2MAX. While only bodyweight changes correlated with MetS Z-score changes (r = 0.372, and = 0.300, respectively). Despite baseline differences, 16-weeks of HIIT similarly improved MetS, cardiorespiratory and metabolic fitness in women and men with MetS. This suggests that there are no restrictions due to sex on the benefits derived from an intense exercise program in the health of MetS participants. Trial Registration: clinicaltrials.gov NCT03019796.

3.
Int J Sports Med ; 40(12): 756-761, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31476782

RESUMO

We studied the effects of supramaximal interval exercise (SIE) with or without antihypertensive medication (AHM) on 21-hr blood pressure (BP) response. Twelve hypertensive patients chronically medicated with AHM, underwent three trials in a randomized order: a) control trial without exercise and substituting their AHM with a placebo (PLAC); b) placebo medicine and a morning bout of SIE (PLAC+SIE), and c) combining AHM and exercise (AHM+SIE). Acute and ambulatory blood pressure responses were measured for 21-hr after treatment. 20 min after treatment, systolic blood pressure (SBP) readings were reduced, similar to readings after PLAC+SIE (-9.7±6.0 mmHg, P<0.001) and AHM+SIE (-10.4±7.9 mmHg, P=0.001). 21 h after treatment, SBP remained reduced after PLAC+SIE (125±12 mmHg, P=0.022) and AHM+SIE (122±12 mmHg, P=0.013) compared to PLAC (132±16 mmHg). The BP reduction in PLAC+SIE faded out at 4 a.m., while in AHM+SIE it continued overnight. At night, BP reduction was larger in AHM+SIE than PLAC+SIE (-5.6±4.0 mmHg, P=0.006). Our data shows that a bout of supramaximal aerobic interval exercise in combination with ARB medication in the morning elicits a sustained blood pressure reduction lasting at least 21-h. Thus, the combination of exercise and angiotensin receptor blocker medication seems superior to exercise alone for acutely decreasing blood pressure.


Assuntos
Anti-Hipertensivos/uso terapêutico , Treinamento Intervalado de Alta Intensidade , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipotensão Pós-Exercício/fisiopatologia , Actigrafia/métodos , Idoso , Pressão Sanguínea/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Monitores de Aptidão Física , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Postura/fisiologia , Estudos de Tempo e Movimento
4.
Med Sci Sports Exerc ; 51(9): 1876-1883, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31415443

RESUMO

PURPOSE: Continuous and interval are the two types of aerobic exercise training commonly used for health promotion. We sought to determine which aerobic exercise training program results in larger health improvements in metabolic syndrome (MetS) individuals. METHODS: One hundred twenty-one MetS patients (age, 57 ± 8 yr; weight, 92 ± 15 kg; and MetS factors, 3.8 ± 0.8 components) with low initial cardiorespiratory fitness (CRF) (V˙O2peak, 24.0 ± 5.5 mL·kg·min) were randomized to undergo one of the following 16-wk exercise program: (a) 4 × 4-min high-intensity interval training at 90% of HRMAX (4HIIT group; n = 32), (b) 50-min moderate-intensity continuous training at 70% of HRMAX (MICT group; n = 35), (c) 10 × 1-min HIIT at 100% of HRMAX (1HIIT group; n = 32), or (d) no exercise control group (CONT; n = 22). We measured the evolution of all five MetS components (i.e., MetS Z Score) and CRF (assessed by V˙O2peak) before and after intervention. RESULTS: MetS Z score decreased 41% after 4HIIT (95% confidence interval [CI], 0.25-0.06; P < 0.01) and 52% in MICT (95% CI, 0.24-0.06; P < 0.01), whereas it did not change in 1HIIT (decreased 24%; 95% CI, -0.16 to 0.03; P = 0.21) and CONT (increased 20%; 95% CI, -0.19 to 0.04; P = 0.22). However, the three exercise groups improved similarly their V˙O2peak (4HIIT, 11%; 95% CI, 0.14-0.33; MICT, 12%; 95% CI, 0.18-0.36; and 1HIIT, 14%; 95% CI, 0.21-0.40 L·min; all P < 0.001). CONCLUSIONS: Our findings suggest that in sedentary individuals with MetS and low initial CRF level any aerobic training program of 16 wk with a frequency of three times per week is sufficient stimulus to raise CRF. However, the more intense but shorter 1HIIT training program is not effective on improving MetS Z score, and thus we caution its recommendation for health promotion purposes in this population.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Terapia por Exercício/métodos , Síndrome Metabólica/fisiopatologia , Síndrome Metabólica/terapia , Idoso , Peso Corporal/fisiologia , Metabolismo Energético/fisiologia , Feminino , Treinamento Intervalado de Alta Intensidade , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Comportamento Sedentário
5.
Eur J Sport Sci ; 19(4): 549-556, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30381027

RESUMO

The aim of the present study was to study if training intensity relative to ventilatory thresholds (VTs) determines the improvements in cardiorespiratory fitness (CRF) in middle-aged sedentary individuals with obesity. Before and after 16-weeks of HIIT (43-min alternating bouts at 70/90% of HRMAX), oxygen consumption ( V˙ O2) and heart rate (HR) at ventilatory threshold 1 ( V˙ O2VT1, HRVT1), ventilatory threshold 2 ( V˙ O2VT2, HRVT2) and at maximal effort ( V˙ O2MAX, HRMAX) were assessed during a graded cycle-ergometer exercise test. Retrospectively, participants were divided into two groups based on whether training intensities were under (UNDER; n = 39) or over (OVER; n = 37) VT1 and VT2. At baseline, age, body composition, V˙ O2VT1, V˙ O2VT2, and HRMAX were similar in both groups. However, V˙ O2MAX was higher in OVER (P = 0.033), whereas HRVT1 and HRVT2 were higher in UNDER (P < 0.05). V˙ O2MAX (9.0%) and HRMAX (2.2%) improved similarly in both groups. V˙ O2VT1 and V˙ O2VT2 improved with training in both groups (P < 0.001) but the improvement was larger in OVER versus UNDER in V˙ O2VT1 (P = 0.013) and tended to be higher in V˙ O2VT2 (P = 0.068). HRVT1 increased only in OVER (P < 0.001), whereas HRVT2 did not change in any group (P = 0.248). A 16-week programme of HIIT improves V˙ O2MAX similarly in individuals training at intensities over or under their VTs. However, individuals training over their VTs showed a larger improvements in V˙ O2VT1 expanding exercise workloads fuelled by oxidative metabolism.


Assuntos
Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade , Obesidade/metabolismo , Consumo de Oxigênio , Composição Corporal , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Sedentário
6.
Med Sci Sports Exerc ; 50(10): 1983-1991, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29781921

RESUMO

PURPOSE: We aimed to determine if yearly repeated exercise training reduces metabolic syndrome (MetS) and the use of medicines to control MetS components. METHODS: Fifty-five MetS individuals were randomized into a TRAIN group that underwent two yearly programs of 16-wk high-intensity interval training or a nonexercising CONT group. We measured the evolution of all five MetS components, cardiorespiratory fitness (assessed by V˙O2PEAK) and medicine use, at baseline (0 months), mid (12 months), and end-point (24 months). Testing took place 8 months after the last training session to assess the chronic effects of training. RESULTS: Daily physical activity (wristband activity monitors) and calorie intake (3-d nutritional diary) remained similar to baseline at 1 and 2 yr in each group and were not different between groups. Blood triglycerides and glucose concentrations did not significantly vary in any group. However, waist circumference increased only in CONT after 2 yr (107 ± 2 cm to 111 ± 3 cm; P = 0.004). Mean arterial pressure decreased in TRAIN (101 ± 2 mm Hg to 94 ± 2 mm Hg; P = 0.002), whereas it remained unchanged in CONT (98 ± 2 mm Hg to 99 ± 2 mm Hg; P = 1.000) after 2 yr. Starting from similar levels at baseline, after 2 yr V˙O2PEAK was higher (2.32 ± 0.14 L·min vs 1.98 ± 0.11 L·min; P = 0.049) and medicine use lower (1.27 ± 0.22 vs 2.23 ± 0.43; P = 0.043) in TRAIN than CONT. The reduction in MAP in TRAIN commanded a parallel reduction in MetS Z-score from baseline to 2 yr (0.30 ± 0.1 to 0.07 ± 0.1; P = 0.013). CONCLUSIONS: Two yearly 16-wk high-intensity interval training programs are enough exercise to chronically lower MetS while preventing the reductions in cardiorespiratory fitness associated to aging. Of clinical relevance, yearly exercise training halts the increase in medicine use that occurs in non-exercising MetS individuals.


Assuntos
Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade , Síndrome Metabólica/terapia , Adulto , Composição Corporal , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/terapia , Método Simples-Cego
7.
Int J Sports Med ; 38(7): 560-567, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28482361

RESUMO

The purpose of this study was to compare the magnitude of post-exercise hypotension (PEH) after a bout of cycling exercise using high-intensity interval training (HIIT) in comparison to a bout of traditional moderate-intensity continuous exercise (CE). After supine rest 14 obese (31±1 kg·m-2) middle-age (57±2 y) metabolic syndrome patients (50% hypertensive) underwent a bout of HIIT or a bout of CE in a random order and then returned to supine recovery for another 45 min. Exercise trials were isocaloric and compared to a no-exercise trial (CONT) of supine rest for a total of 160 min. Before and after exercise we assessed blood pressure (BP), heart rate (HR), cardiac output (Q), systemic vascular resistance (SVR), intestinal temperature (TINT), forearm skin blood flow (SKBF) and percent dehydration. HIIT produced a larger post-exercise reduction in systolic blood pressure than CE in the hypertensive group (-20±6 vs. -5±3 mmHg) and in the normotensive group (-8±3 vs. -3±2 mmHg) while HIIT reduced SVR below CE (P<0.05). Percent dehydration was larger after HIIT, and post-exercise TINT and SKBF increased only after HIIT (all P<0.05). Our findings suggest that HIIT is a superior exercise method to CE to acutely reduce blood pressure in MSyn subjects.


Assuntos
Exercício/fisiologia , Treinamento Intervalado de Alta Intensidade , Síndrome Metabólica/fisiopatologia , Hipotensão Pós-Exercício/fisiopatologia , Pressão Sanguínea , Temperatura Corporal , Desidratação/fisiopatologia , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Resistência Vascular
8.
Med Sci Sports Exerc ; 49(3): 518-526, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27787335

RESUMO

PURPOSE: The health benefits of a training program are largely influenced by the exercise dose and intensity. We sought to determine whether during a training bout of continuous versus interval exercise the workload needs to be reduced to maintain the prescribed target heart rate (HR). METHODS: Fourteen obese (31 ± 4 kg·m) middle-age (57 ± 8 yr) individuals with metabolic syndrome, underwent two exercise training bouts matched by energy expenditure (i.e., 70 ± 5 min of continuous exercise [CE] or 45 min of interval exercise, high-intensity interval training [HIIT]). All subjects completed both trials in a randomized order. HR, power output (W), percent dehydration, intestinal and skin temperature (TINT and TSK), mean arterial pressure, cardiac output (CO), stroke volume (SV), and blood lactate concentration (La) were measured at the initial and latter stages of each trial to assess time-dependent drift. RESULTS: During the HIIT trial, power output was lowered by 30 ± 16 W to maintain the target HR, whereas a 10 ± 11 W reduction was needed in the CE trial (P < 0.05). Energy expenditure, CO, and SV declined with exercise time only in the HIIT trial (15%, 10%, and 13%, respectively). During HIIT, percent dehydration, TINT, and TSK increased more than during the CE trial (all P = 0.001). Mean arterial pressure and La were higher in HIIT without time drift in any trial. CONCLUSION: Our findings suggests that while CE results in mild power output reductions to maintain target HR, the increasingly popular HIIT results in marked reductions in power output, energy expenditure, and CO (21%, 15%, and 10%, respectively). HIIT based on target HR may result in lower than expected training adaptations because of workload adjustments to avoid HR drift.


Assuntos
Frequência Cardíaca/fisiologia , Treinamento Intervalado de Alta Intensidade , Síndrome Metabólica/fisiopatologia , Condicionamento Físico Humano/métodos , Pressão Sanguínea , Temperatura Corporal , Débito Cardíaco , Desidratação/fisiopatologia , Metabolismo Energético , Humanos , Ácido Láctico/sangue , Pessoa de Meia-Idade , Temperatura Cutânea , Volume Sistólico
9.
PLoS One ; 11(9): e0163389, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27657502

RESUMO

PURPOSE: The purpose of this study was to determine, i) the reliability of blood lactate and ventilatory-based thresholds, ii) the lactate threshold that corresponds with each ventilatory threshold (VT1 and VT2) and with maximal lactate steady state test (MLSS) as a proxy of cycling performance. METHODS: Fourteen aerobically-trained male cyclists ([Formula: see text] 62.1±4.6 ml·kg-1·min-1) performed two graded exercise tests (50 W warm-up followed by 25 W·min-1) to exhaustion. Blood lactate, [Formula: see text] and [Formula: see text] data were collected at every stage. Workloads at VT1 (rise in [Formula: see text];) and VT2 (rise in [Formula: see text]) were compared with workloads at lactate thresholds. Several continuous tests were needed to detect the MLSS workload. Agreement and differences among tests were assessed with ANOVA, ICC and Bland-Altman. Reliability of each test was evaluated using ICC, CV and Bland-Altman plots. RESULTS: Workloads at lactate threshold (LT) and LT+2.0 mMol·L-1 matched the ones for VT1 and VT2, respectively (p = 0.147 and 0.539; r = 0.72 and 0.80; Bias = -13.6 and 2.8, respectively). Furthermore, workload at LT+0.5 mMol·L-1 coincided with MLSS workload (p = 0.449; r = 0.78; Bias = -4.5). Lactate threshold tests had high reliability (CV = 3.4-3.7%; r = 0.85-0.89; Bias = -2.1-3.0) except for DMAX method (CV = 10.3%; r = 0.57; Bias = 15.4). Ventilatory thresholds show high reliability (CV = 1.6%-3.5%; r = 0.90-0.96; Bias = -1.8-2.9) except for RER = 1 and V-Slope (CV = 5.0-6.4%; r = 0.79; Bias = -5.6-12.4). CONCLUSIONS: Lactate threshold tests can be a valid and reliable alternative to ventilatory thresholds to identify the workloads at the transition from aerobic to anaerobic metabolism.

10.
Med Sci Sports Exerc ; 48(5): 822-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26694843

RESUMO

PURPOSE: The objective of this study is to determine whether muscle water content (H2Omuscle) expands with training in deconditioned middle-age men and the effects of this expansion in other muscle metabolites. METHODS: Eighteen obese (BMI = 33 ± 3 kg⁻¹·m⁻²) untrained (V˙O2peak = 29 ± 7 mL⁻¹·kg⁻¹·min⁻¹) metabolic syndrome men completed a 4-month aerobic cycling training program. Vastus lateralis muscle biopsies were collected before and 72 h after the completion of the last training bout. Water content, total protein, glycogen concentration, and citrate synthase activity were measured in biopsy tissue. Body composition was assessed using dual-energy X-ray absorptiometry, and cardiometabolic fitness was measured during an incremental cycling test. RESULTS: Body weight and fat mass were reduced -1.9% and -5.4%, respectively (P < 0.05), whereas leg fat free mass increased with training (1.8%, P = 0.023). Cardiorespiratory fitness (i.e., V˙O2peak), exercise maximal fat oxidation (i.e., FOmax), and maximal cycling power (i.e., Wmax) improved with training (11%, 33%, and 10%, respectively; P < 0.05). After 4 months of training, H2Omuscle increased from 783 ± 18 to 799 ± 24 g·kg⁻¹ wet weight (ww) (2%, P = 0.011), whereas muscle protein concentration decreased 11% (145 ± 15 to 129 ± 13 g·kg⁻¹ ww, P = 0.007). Citrate synthase activity (proxy for mitochondrial density) increased by 31% (17 ± 5 to 22 ± 5 mmol·min⁻¹·kg⁻¹ ww, P = 0.024). Muscle glycogen concentration increased by 14% (22 ± 7 to 25 ± 7 g·kg⁻¹ ww) although without reaching statistical significance when expressed as per kilogram of wet weight (P = 0.15). CONCLUSIONS: Our findings suggest that aerobic cycling training increases quadriceps muscle water although reduces muscle protein concentration in obese metabolic syndrome men. Reduced protein concentration coexists with increased leg lean mass suggestive of a water dilution effect that however does not impair increased cycling leg power with training.


Assuntos
Ciclismo/fisiologia , Exercício/fisiologia , Obesidade/metabolismo , Músculo Quadríceps/metabolismo , Água/metabolismo , Adulto , Composição Corporal , Aptidão Cardiorrespiratória , Glicogênio/metabolismo , Humanos , Masculino , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade , Proteínas Musculares/metabolismo
11.
Appl Physiol Nutr Metab ; 39(7): 787-92, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24971679

RESUMO

The aim of the present study was to determine which of the available glucose tolerance tests (oral (OGTT) vs. intravenous (IVGTT)) could more readily detect the insulin sensitizing effects of a bout of continuous exercise. Ten healthy moderately fit young men (V̇O2peak of 45.4 ± 1.8 mL·kg(-1)·min(-1); age 27.5 ± 2.7 yr) underwent 4 OGTT and 4 IVGTT on different days following a standardized dinner and overnight fast. One test was performed immediately after 55 min of cycle-ergometer exercise at 60% V̇O2peak. Insulin sensitivity index was determined during a 50 min IVGTT according to Tura (CISI) and from a 120 min OGTT using the Matsuda composite index (MISI). After exercise, MISI improved 29 ± 10% without reaching statistical significance (p = 0.182) due to its low reproducibility (coefficient of variation 16 ± 3%; intra-class reliability 0.846). However, CISI significantly improved (50 ± 4%; p < 0.001) after exercise showing better reproducibility (coefficient of variation 13 ± 4%; intra-class reliability 0.955). Power calculation revealed that 6 participants were required for detecting the effects of exercise on insulin sensitivity when using IVGTT, whereas 54 were needed when using OGTT. The superior response of CISI compared with MISI suggests the preferential use of IVGTT to assess the effects of exercise on insulin sensitivity when using a glucose tolerance test.


Assuntos
Exercício/fisiologia , Teste de Tolerância a Glucose/métodos , Resistência à Insulina , Adulto , Estudos Cross-Over , Humanos , Masculino , Reprodutibilidade dos Testes
12.
Appl Physiol Nutr Metab ; 38(1): 42-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23368827

RESUMO

A high saturated fatty acids diet (HSFAD) deteriorates metabolic and cardiovascular health while aerobic training improves them. The aim of this study was to investigate in physically inactive and overweight people if 2 weeks of HSFAD leads to hyperlipemia or insulin resistance and if concurrent aerobic exercise training counteracts those effects. Fourteen overweight (body mass index, 27.5 ± 0.6 kg·m(-2)), healthy, young individuals (aged 24.8 ± 1.8 years) were randomly assigned to a diet (D) or a diet plus exercise (D + E) group. During 14 consecutive days both groups increased dietary saturated fatty acids from 31 ± 10 to 52 ± 14 g·day(-1) (p < 0.001) while maintaining total fat intake. Concurrent to the diet, the D + E group underwent 11 cycle-ergometer sessions of 55 min at 60% peak oxygen uptake (V˙O(2peak)). Before and after intervention, insulin sensitivity and body composition were estimated, and blood lipids, resting blood pressure, and VO(2peak) were measured. Body weight and composition, plasma free fatty acids composition and concentration, and insulin sensitivity remained unchanged in both groups. However, post-intervention total cholesterol (T(C)) and low-density lipoprotein cholesterol (LDL-C) increased above pre-intervention values in the D group (147 ± 8 to 161 ± 9 mg·dL(-1), p = 0.018 and 71 ± 10 to 82 ± 10 mg·dL(-1), p = 0.034, respectively). In contrast, in the D + E group, T(C) and LDL-C remained unchanged (153 ± 20 to 157 ± 24 mg·dL(-1) and 71 ± 21 to 70 ± 25 mg·dL(-1)). Additionally, the D + E group lowered systolic blood pressure (6 ± 2 mm Hg, p = 0.029) and increased VO(2peak) (6 ± 2 mL·kg(-1)·min(-1), p = 0.020). Increases in T(C) and LDL-C concentration induced by 14 days of HSFAD can be prevented by concurrent aerobic exercise training, which, in addition, improves cardiorespiratory fitness.


Assuntos
Colesterol/sangue , Dieta Hiperlipídica/métodos , Gorduras na Dieta/sangue , Exercício/fisiologia , Sobrepeso/sangue , Adulto , Ciclismo/fisiologia , Biomarcadores/sangue , Pressão Sanguínea , Composição Corporal , Peso Corporal , Gorduras na Dieta/administração & dosagem , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/prevenção & controle , Resistência à Insulina , Lipídeos/sangue , Masculino , Adulto Jovem
13.
PLoS One ; 7(4): e33807, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22496767

RESUMO

PURPOSE: To investigate whether caffeine ingestion counteracts the morning reduction in neuromuscular performance associated with the circadian rhythm pattern. METHODS: Twelve highly resistance-trained men underwent a battery of neuromuscular tests under three different conditions; i) morning (10:00 a.m.) with caffeine ingestion (i.e., 3 mg kg(-1); AM(CAFF) trial); ii) morning (10:00 a.m.) with placebo ingestion (AM(PLAC) trial); and iii) afternoon (18:00 p.m.) with placebo ingestion (PM(PLAC) trial). A randomized, double-blind, crossover, placebo controlled experimental design was used, with all subjects serving as their own controls. The neuromuscular test battery consisted in the measurement of bar displacement velocity during free-weight full-squat (SQ) and bench press (BP) exercises against loads that elicit maximum strength (75% 1RM load) and muscle power adaptations (1 m s(-1) load). Isometric maximum voluntary contraction (MVC(LEG)) and isometric electrically evoked strength of the right knee (EVOK(LEG)) were measured to identify caffeine's action mechanisms. Steroid hormone levels (serum testosterone, cortisol and growth hormone) were evaluated at the beginning of each trial (PRE). In addition, plasma norepinephrine (NE) and epinephrine were measured PRE and at the end of each trial following a standardized intense (85% 1RM) 6 repetitions bout of SQ (POST). RESULTS: In the PM(PLAC) trial, dynamic muscle strength and power output were significantly enhanced compared with AM(PLAC) treatment (3.0%-7.5%; p≤0.05). During AM(CAFF) trial, muscle strength and power output increased above AM(PLAC) levels (4.6%-5.7%; p≤0.05) except for BP velocity with 1 m s(-1) load (p = 0.06). During AM(CAFF), EVOK(LEG) and NE (a surrogate of maximal muscle sympathetic nerve activation) were increased above AM(PLAC) trial (14.6% and 96.8% respectively; p≤0.05). CONCLUSIONS: These results indicate that caffeine ingestion reverses the morning neuromuscular declines in highly resistance-trained men, raising performance to the levels of the afternoon trial. Our electrical stimulation data, along with the NE values, suggest that caffeine increases neuromuscular performance having a direct effect in the muscle.


Assuntos
Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Ritmo Circadiano , Exercício , Força Muscular/efeitos dos fármacos , Treinamento de Resistência , Adulto , Estudos de Casos e Controles , Estudos Cross-Over , Método Duplo-Cego , Ingestão de Alimentos , Humanos , Masculino , Força Muscular/fisiologia , Resistência Física/efeitos dos fármacos , Testosterona/sangue , Adulto Jovem
14.
Appl Physiol Nutr Metab ; 35(6): 741-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21164544

RESUMO

The purpose of this study was to determine whole-body fat oxidation in endurance-trained (TR) and untrained (UNTR) subjects exercising at different intensities in the heat. On 3 occasions, 10 TR cyclists and 10 UNTR healthy subjects (peak oxygen uptake = 60 ± 6 vs. 44 ± 3 mL·kg-1·min-1; p < 0.05) exercised at 40%, 60%, and 80% peak oxygen uptake in a hot, dry environment (36 °C; 25% relative humidity). To complete the same amount of work in all 3 trials, exercise duration varied (107 ± 4, 63 ± 1, and 45 ± 0 min for 40%, 60%, and 80% peak oxygen uptake, respectively). Substrate oxidation was calculated using indirect calorimetry. Blood samples were collected at the end of exercise to determine plasma epinephrine ([EPI]plasma) and norepinephrine ([NEPI]plasma) concentrations. The maximal rate of fat oxidation was achieved at 60% peak oxygen uptake for the TR group (0.41 ± 0.01 g·min-1) and at 40% peak oxygen uptake for the UNTR group (0.28 ± 0.01 g·min-1). TR subjects oxidized absolutely (g·min-1) and relatively (% of total energy expenditure) more fat than UNTR subjects at 60% and 80% peak oxygen uptake (p < 0.05). At these exercise intensities, TR subjects also had higher [NEPI]plasma concentrations than UNTR subjects (p < 0.05). In the heat, whole-body peak fat oxidation occurs at higher relative exercise intensities in TR than in UNTR subjects (60% vs. 40% peak oxygen uptake). Moreover, TR subjects oxidize more fat than UNTR subjects when exercising at moderate to high intensities (>60% peak oxygen uptake).


Assuntos
Exercício/fisiologia , Temperatura Alta , Metabolismo dos Lipídeos , Aptidão Física/fisiologia , Adolescente , Adulto , Algoritmos , Ciclismo , Calorimetria Indireta , Metabolismo Energético , Epinefrina/sangue , Humanos , Norepinefrina/sangue , Oxirredução , Consumo de Oxigênio , Resistência Física/fisiologia , Fatores de Tempo , Adulto Jovem
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