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1.
Phys Sportsmed ; 52(1): 65-76, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36752064

RESUMO

BACKGROUND: Supplementation with Angiotensin-(1-7) [(Ang-1-7)] has received considerable attention due to its possible ergogenic effects on physical performance. The effects of a single dose of Ang-(1-7) on the performance of mountain bike (MTB) athletes during progressive load tests performed until the onset of voluntary fatigue have previously been demonstrated. This study tested the effects of Ang-(1-7) in two different exercise protocols with different metabolic demands: aerobic (time trial) and anaerobic (repeated sprint). METHODS: Twenty one male recreational athletes were given capsules containing an oral formulation of HPßCD-Ang-(1-7) (0.8 mg) and HPßCD-placebo (only HPßCD) over a 7-day interval; a double-blind randomized crossover design was used. Physical performance was examined using two protocols: a 20-km cycling time trial or 4 × 30-s repeated all-out sprints on a leg cycle ergometer. Data were collected before and after physical tests to assess fatigue parameters, and included lactate levels, and muscle activation during the sprint protocol as evaluated by electromyography (EMG); cardiovascular parameters: diastolic and systolic blood pressure and heart rate; and performance parameters, time to complete (time trial), maximum power and mean power (repeated sprint). RESULTS: Supplementation with an oral formulation of HPßCD-Ang-(1-7) reduced basal plasma lactate levels and promoted the maintenance of plasma glucose levels after repeated sprints. Supplementation with HPßCD-Ang-(1-7) also increased baseline plasma nitrite levels and reduced resting diastolic blood pressure in a time trial protocol. HPßCD-Ang-(1-7) had no effect on the time trial or repeat sprint performance, or on the EMG recordings of the vastus lateralis and vastus medialis. CONCLUSIONS: Supplementation with HPßCD-Ang-(1-7) did not improve physical performance in time trial or in repeated sprints; however, it promoted the maintenance of plasma glucose and lactate levels after the sprint protocol and at rest, respectively. In addition, HPßCD-Ang-(1-7) also increased resting plasma nitrite levels and reduced diastolic blood pressure in the time trial protocol. TRIAL REGISTRATION: RBR-2nbmpbc, registered January 6th, 2023. The study was prospectively registered.


Assuntos
Angiotensina I , Desempenho Atlético , Nitritos , Fragmentos de Peptídeos , Humanos , Masculino , Estudos Cross-Over , 2-Hidroxipropil-beta-Ciclodextrina , Ciclismo/fisiologia , Glicemia , Lactatos , Suplementos Nutricionais , Atletas , Fadiga
2.
Nutrients ; 15(14)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37513549

RESUMO

Intermittent fasting (IF) is commonly used by combat sports athletes for weight loss. However, IF can decrease performance. This study aimed to investigate the effect of IF on total body mass (TBM) and Taekwondo performance. Nine athletes (seven male, two female; 18.4 ± 3.3 years) underwent 4 weeks of 12 h IF. TBM, countermovement jump (CMJ), mean kicks (MK), and total number of kicks (TNK) were compared weekly. Performance was measured in the fed state (FED) and fast state (FAST). Results showed decreased TBM in week 1 (62.20 ± 6.56 kg; p = 0.001) and week 2 (62.38 ± 6.83 kg; p = 0.022) compared to pre-intervention (63.58 ± 6.57 kg), stabilizing in week 3 (62.42 ± 6.12 kg), and no significant change in week 4 (63.36 ± 6.20 kg). CMJ performance in week 1 was lower in FED (35.26 ± 7.15 cm) than FAST (37.36 ± 6.77 cm; p = 0.003), but in week 3, FED (38.24 ± 6.45 cm) was higher than FAST (35.96 ± 5.05 cm; p = 0.047). No significant differences were found in MK and TNK in FSKTmult. RPE, KDI, and HR were similar between FED and FAST (p < 0.05). [LAC] was higher post-test compared to pre-test (p = 0.001), with higher concentrations in FED than FAST (p = 0.020). BG was higher in FED than FAST (p < 0.05) before physical tests. Therefore, IF promotes decreased TBM without decreasing performance.


Assuntos
Desempenho Atlético , Artes Marciais , Humanos , Masculino , Feminino , Jejum Intermitente , Redução de Peso , Atletas
3.
Biology (Basel) ; 11(4)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35453772

RESUMO

BACKGROUND: to evaluate the effects of one week of supplementation with curcumin combined with piperine on physical performance, immune system cell counts, muscle damage, and plasma levels of inflammatory markers after a treadmill running training session. METHODS: This study is a double-blind, crossover-balanced clinical trial with a three-week intervention. Sixteen male runners with a mean age of 36 ± 9 years and VO2 max of 60.6 ± 9.03 mL.kg -1 min -1 were recruited and randomly divided into 2 groups: the first group (CPG) was supplemented daily for 7 days with 500 mg of curcumin + 20 mg piperine, and the second group (PG) was supplemented with 540 mg of cellulose. After the 7th day of supplementation, the volunteers participated in the experimental running protocol, where blood samples were collected before, after, and one hour after exercise for analysis of the number of leukocytes, creatine kinase, and cytokine concentration (IL-2, TNF-α, IFN, IL-6, and IL-10) using flow cytometry. This process was repeated, reversing the supplementation offered to the groups. RESULTS: curcumin and piperine supplementation could not change the physical performance, immune cell counts, and muscle damage; however, the aerobic fatiguing exercise protocol inhibited the elevation of the plasmatic levels of some cytokines. The running exercise protocol could elevate the circulating levels of IL-2 (from 49.7 to 59.3 pg/mL), TNF-α (from 48.5 to 51.5 pg/mL), INF (from 128.8 to 165.0 pg/mL), IL-6 (from 63.1 to 77.3 pg/mL), and IL-10 (from 48.9 to 59.6 pg/mL) 1 h after the end of the running protocol. However, the curcumin and piperine supplementation could inhibit this elevation. CONCLUSIONS: curcumin and piperine supplementation had no effect on physical performance, immune cell counts, or muscle damage; however, the supplementation could modulate the kinetics of IL-2, TNF-α, INF, IL-6, and IL-10 1 h after the end of exercise.

4.
BMC Sports Sci Med Rehabil ; 13(1): 47, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33957973

RESUMO

BACKGROUND: The ECA2/Ang-(1-7)/Mas axis is shown to be involved in effects mediated by physical exercise, as it can induce the release of nitric oxide (ON) and bradykinin (BK), which are potent vasodilators. The vasodilating action the NO/BK can contribute to increased metabolic efficiency in muscle tissue and central nervous system. The formulation HPß-CD-Ang-(1-7) through its mechanisms of action can be a promising supplement to aid in the maintenance and improvement of performance and may also favor recovery during competitions. The premise of this study was to investigate the effects of acute oral supplementation HPß-CD-Ang-(1-7) on the performance of mountain bike (MTB) practitioners. METHODS: Fourteen recreational athletes, involved in training programs for at least one year, participated in this crossover design study. Subjects underwent two days of testing with a seven-day interval. HPß-CD-Ang-(1-7) (1.75 mg) and HPßCD-Placebo were provided in capsules three hours prior to tests. To determine the safety of the HPß-CD-Ang-(1-7) formulation associated with physical effort, cardiovascular parameters heart rate (HR) and blood pressure (BP) were analyzed. Physical performance was measured using maximal oxygen uptake (VO2), total exercise time (TET), mechanical work (MW), mechanical efficiency (ME), and rating of perceived exertion (RPE). Respiratory exchange coefficient (REC), lactate and non-esterified fatty acids (NEFAs) were measured. Maximal incremental tests were performed on a progressively loaded leg cycle ergometer. RESULTS: There were no significant differences in terms of HR or BP at rest and maximum effort between the HPß-CD-Ang-(1-7) and placebo groups. The VO2max showed significant differences (p = 0.04). It was higher in the Ang-(1-7)condition (66.15 mlO2.kg- 1.min- 1) compared to the placebo (60.72 mlO2.kg- 1.min- 1). This was also observed for TET (Ang-(1-7) 39.10 min vs. placebo 38.14 min; p = 0.04), MW (Ang-(1-7) 156.7 vs. placebo 148.2; p = 0.04), and at the lowest RPE (Ang-(1-7) vs. placebo; p = 0.009). No significant differences were observed for REC, NEFAs, or Lactate. CONCLUSIONS: These results suggest that HPß-CD-Ang-(1-7) improves the physical performance of MTB recreational athletes and could be a promising supplement. TRIAL REGISTRATION: RBR-2 × 56pw8, registered January 15th, 2021. The study was prospectively registered.

5.
Exp Physiol ; 106(2): 412-426, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33347659

RESUMO

NEW FINDINGS: What is the central question of this study? How does swimming exercise training impact hydro-electrolytic balance, renal function, sympathetic contribution to resting blood pressure and cerebrospinal fluid (CSF) [Na+ ] in rats fed a high-sodium diet from weaning? What is the main finding and its importance? An exercise-dependent reduction in blood pressure was associated with decreased CSF [Na+ ], sympathetically driven vasomotor tonus and renal fibrosis indicating that the anti-hypertensive effects of swimming training in rats fed a high-sodium diet might involve neurogenic mechanisms regulated by sodium levels in the CSF rather than changes in blood volume. ABSTRACT: High sodium intake is an important factor associated with hypertension. High-sodium intake with exercise training can modify homeostatic hydro-electrolytic balance, but the effects of this association are mostly unknown. In this study, we sought to investigate the effects of swimming training (ST) on cerebrospinal fluid (CSF) Na+ concentration, sympathetic drive, blood pressure (BP) and renal function of rats fed a 0.9% Na+ (equivalent to 2% NaCl) diet with free access to water for 22 weeks after weaning. Male Wistar rats were assigned to two cohorts: (1) fed standard diet (SD) and (2) fed high-sodium (HS) diet. Each cohort was further divided into trained and sedentary groups. ST normalised BP levels of HS rats as well as the higher sympathetically related pressor activity assessed by pharmacological blockade of ganglionic transmission (hexamethonium). ST preserved the renal function and attenuated the glomerular shrinkage elicited by HS. No change in blood volume was found among the groups. CSF [Na+ ] levels were higher in sedentary HS rats but were reduced by ST. Our findings showed that ST effectively normalised BP of HS rats, independent of its effects on hydro-electrolytic balance, which might involve neurogenic mechanisms regulated by Na+ levels in the CSF as well as renal protection.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Rim/fisiopatologia , Sódio na Dieta , Animais , Sistema Nervoso Autônomo/patologia , Dieta , Frequência Cardíaca/fisiologia , Hipertensão/patologia , Rim/patologia , Masculino , Condicionamento Físico Animal , Ratos , Ratos Wistar , Natação , Equilíbrio Hidroeletrolítico
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