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The present randomized study investigated the effect of acute supplementation of 800 mg/kg of ketone monoester ingestion (KE) or placebo (PL) and 210 mg/kg of NaHCO3 co-ingestion on cycling performance of WorldTour cyclists during a road cycling stage simulation. Twenty-eight cyclists participated in the study (27.46 ± 4.32 years; 1.80 ± 0.06 m; 69.74 ± 6.36 kg). Performance, physiological, biochemical, and metabolism outcomes, gut discomfort, and effort perceived were assessed during a road cycling simulation composed of an 8-min time-trial (TT) performance + 30-s TT + 4.5 hr of outdoor cycling + a second 8-min TT + a second 30-s TT. Greater absolute and relative mean power during the first 8-min TT (F = 5.067, p = .033, ηp2=.163, F = 5.339, p = .029, ηp2=.170, respectively) was observed after KE than after PL (KE: 389 ± 34, PL: 378 ± 44 W, p = .002, d = 0.294 and KE: 5.60 ± 0.42, PL: 5.41 ± 0.44 W/kg, p = .001, d = 0.442). Additionally, greater concentration of ß-hydroxybutyrate blood concentration (F = 42.195, p < .001, ηp2=.619) was observed after KE than after PL during the first steps of the stage (e.g., after warm-up KE: 1.223 ± 0.642, PL: 0.044 ± 0.058 mM, p < .001, d = 2.589), although the concentrations returned to near baseline after 4.5 hr of outdoor cycling. Moreover, higher values of anion gap were observed (F = 2.333, p = .026, ηp2=.080) after KE than after PL ingestion, after the warm-up and after the first 8-min and 30-s TT. Additionally, lower concentrations of HCO3- were reported in the KE condition after warm-up and after the first 8-min and 30-s TT. During the initial phase of the stage simulation, acute supplementation with KE + NaHCO3 co-ingestion enhanced 8-min TT cycling performance (3.1%) in WorldTour cyclists with a concomitant hyperketonaemia.
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Desempenho Atlético , Bicarbonatos , Humanos , Ciclismo , Cetonas , Bicarbonato de Sódio/farmacologia , Ingestão de Alimentos , Método Duplo-CegoRESUMO
Resistance training (RT) variables can affect sleep quality, strength recovery and performance. The aim of this study was to examine the acute effect of RT leading to failure vs. non-failure on sleep quality (SQ), heart rate variability (HRV) overnight and one-repetition maximum (1-RM) performance 24 hours after training. Fifteen resistance-trained male athletes (age: 23.4 ± 2.4 years; height 178.0 ± 7.6 cm; weight: 78.2 ± 10.6 kg) performed two training sessions in a randomized order, leading to failure (4x10) or non-failure (5x8(10) repetitions), with 90 seconds for resting between sets at 75% 1-RM in bench press (BP) and half squat (HS). The day after, the participants completed the predicted 1-RM test for both exercises. In addition, the subjective and actigraphic SQ and HRV during sleep were measured after each training session. The day after the training protocol leading to failure, the 1-RM of BP (MD = 7.24 kg; -7.2%; p < 0.001) and HS (MD = 20.20 kg; -11.1%; p < 0.001) decreased. However, this parameter did not decrease after a non-failure RT session. No differences were observed between failure and non-failure training sessions on SQ and HRV; therefore, both types of training sessions similarly affected the SQ and the autonomic modulation during the night after the training session. This study provides an insight into the influence of different training strategies on SQ, strength performance and recovery after moderate- to high-demand training. This information could be useful especially for professional coaches, weightlifters and bodybuilders, due to the potential influence on the programming processes.
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PURPOSE: The aim of this study was to analyze the effect of hypoxia on metabolic and acid-base balance, blood oxygenation, electrolyte, and half-squat performance variables during high-resistance circuit (HRC) training. METHODS: Twelve resistance-trained subjects participated in this study. After a 6RM testing session, participants performed three randomized trials of HRC: normoxia (NORM: FiO2 = 0.21), moderate hypoxia (MH: FiO2 = 0.16), or high hypoxia (HH: FiO2 = 0.13), separated by 72 h of recovery in normoxic conditions. HRC consisted of two blocks of three exercises (Block 1: bench press, deadlift and elbow flexion; Block 2: half-squat, triceps extension, and ankle extension). Each exercise was performed at 6RM. Rest periods lasted for 35 s between exercises, 3 min between sets, and 5 min between blocks. Peak and mean force and power were determined during half-squat. Metabolic, acid-base balance, blood oxygenation and electrolyte variables, arterial oxygen saturation (SaO2), and rating of perceived exertion (RPE) were measured following each block. RESULTS: During the first set, peak force and power were significantly lower in HH than MH and NORM; whereas in the second set, mean and peak force and power were significantly lower in HH than NORM. At the end of the HRC training session, blood lactate and RPE in HH were significantly higher than in MH and NORM. SaO2, pH, HCO3-, and pO2 values were significantly lower in all hypoxic conditions than in NORM. CONCLUSION: These results indicate that simulated hypoxia during HRC exercise reduce blood oxygenation, pH, and HCO3-, and increased blood lactate ultimately decreasing muscular performance.
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Limiar Anaeróbio , Tolerância ao Exercício , Treinamento Intervalado de Alta Intensidade , Hipóxia/fisiopatologia , Treinamento Resistido , Adulto , Bicarbonatos/sangue , Humanos , Ácido Láctico/sangue , Masculino , Oxigênio/sangue , Equilíbrio HidroeletrolíticoRESUMO
A randomized, double-blind and controlled study was conducted to assess the effectiveness of the intake of 250 mL of lactose-free skimmed milk enriched with ashwagandha (Withania somnifera) alone or combined with tryptophan vs. non-enriched milk (control) on the subjective quality of sleep in healthy adults with sleep problems. The duration of supplementation was 90 days. Fifty-two eligible subjects were assigned to the study arms of ashwagandha 250 mg, ashwagandha 250 mg plus tryptophan 175 mg, ashwagandha 600 mg, and control with 13 subjects in each group. It was hypothesized that ashwagandha plus tryptophan could be superior to ashwagandha alone for improving sleep-related variables. Changes in the visual analogue scale (VAS) for sleep quality were significantly higher in the three experimental groups as compared with controls (p = 0.014). Improvements in the subscales of the Pittsburg Sleep Quality Index (PSQI) were found in all groups, but between-group differences were not significant. In the index of insomnia severity, decreases were higher in the three experimental groups as compared with controls especially in the group of ashwagandha 600 mg. Daytime somnolence was also reduced in the three experimental groups. Changes in anxiety levels and Morningness-Eveningness Questionnaire were not observed. The study products did not elicit changes in body composition and were well tolerated and safe. The data did not support the hypothesis, as the combination of ashwagandha and tryptophan did not show greater benefits in improving sleep quality than ashwagandha alone. However, the results from the three experimental groups containing ashwagandha were more favorable compared to the placebo group.
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Seventy-one healthy subjects with sleep disturbances participated in a randomized, double-blind controlled trial in which dietary supplementation with an extract of Aloysia citrodora (lemon verbena) (n = 33) or placebo (n = 38) was administered for 90 days. There were between-group differences in favor of the experimental group in the visual analogue scale (VAS) for sleep quality (6.5 ± 1.6 vs. 5.5 ± 2.1, p = 0.021) as well as in the overall score (5.8 ± 2.4, p = 0.008) and scores for sleep latency (1.6 ± 1.0 vs. 1.9 ± 0.7, p = 0.027) and sleep efficiency (84.5 ± 12.8 vs. 79.8 ± 13.6, p = 0.023) in the Pittsburgh Sleep Quality Index (PSQI). Sleep-related variables (latency, efficiency, wakefulness after sleep onset, awakenings) assessed by actigraphy also showed better scores in the experimental group (p = 0.001). Plasma nocturnal melatonin levels also increased significantly in the experimental group (199.7 ± 135.3 vs. 174.7 ± 115.4 pg/mL, p = 0.048). Changes in anthropometric parameters and physical activity levels were not found. In summary, a dietary supplement of lemon verbena administered for 3 months was associated with a significant improvement in sleep quality as compared with placebo in a population of healthy subjects with sleep problems.
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Suplementos Nutricionais , Extratos Vegetais , Qualidade do Sono , Humanos , Método Duplo-Cego , Masculino , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Feminino , Adulto , Pessoa de Meia-Idade , Melatonina/administração & dosagem , Voluntários Saudáveis , Adulto Jovem , Sono/efeitos dos fármacos , Transtornos do Sono-VigíliaRESUMO
Background: Back pain is a common health problem that affects both workers and older people, reducing their quality of life. The primary objective was to assess the effect of dietary supplementation with plant extracts of rosemary, ashwagandha, and sesame consumed for 12 weeks on the intensity of back pain. Methods: A single-center randomized double-blind study with three parallel arms depending on the product consumed. The duration of treatment was 12 weeks. The investigational product, Berelief®, contained a blend of three polyphenolic standardized extracts: rosemary (Rosmarinus officinalis L.), ashwagandha (Withania somnifera L.), and sesame (Sesamum indicum L.) seed. Two doses were tested: low dose (400 mg) and high dose (800 mg). There were 42 subjects in the placebo group, 39 in the low dose and 42 in the high dose groups. Study variables included back pain intensity [VAS score, Patient-Reported Outcomes Measurement Information System (PROMIS-29), and Cornell Musculoskeletal Discomfort Questionnaire; functionality Roland-Morris Disability (RMD) questionnaire]; quality of life (QoL) [36-item Short Form Survey (SF-36), the Beck Depression Inventory-II (BDI-II), the State-Trait Anxiety Inventory (STAI), and the Perceived Stress Scale (PSS)]; sleep quality [accelerometer and Pittsburgh Sleep Quality Index (PSQI)]. Results: The improvement in back pain recorded by the visual analogue scale (VAS) at the study visits after the beginning of treatment, as well as on a weekly basis recorded in the diary card was significantly higher in the intervention group than in the placebo group (p < 0.044 dose-low; p < 0.005 dose-high). Significant differences in pain intensity of the PROMIS-29 (p = 0.002) and upper back pain in the Cornell questionnaire (p = 0.011) in favour of the investigational product were found. Furthermore, benefits in improving health-related quality of life, mood and sleep quality were also detected. Conclusion: Dietary supplementation for 12 weeks of a blend of polyphenolic standardized extracts of rosemary, ashwagandha, and sesame was effective in reducing the intensity of pain in subjects with chronic myofascial cervical and back pain.
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BACKGROUND: The aim of the present study was to analyse the effect of 12âweeks of training, 7âweeks of detraining and 16âweeks of retraining using a moderate or high intensity training programme on cardiovascular risk factors in hypertensive patients. METHOD: Thirty-four patients took part in the study. The intensity training was 80-90% of maximum heart rate for the high-intensity training (HIT) group ( n â=â15) and at 50-70% of maximum heart rate for the moderate training (MT) group ( n â=â19). Blood pressure, body composition, lipid profile, fasting glucose, strength and cardiovascular fitness were analysed. RESULTS: The first training period did not decrease blood pressure, but the second training period saw significant decreases in blood pressures in HIT group. Moreover, 12âweeks of MT or HIT did not decrease body mass, body mass index or fat mass. However, after 7âweeks of detraining, the inclusion of a second training period using HIT saw decreases in these body composition variables. Both training periods and intensities improved high-density lipoprotein and low-density lipoprotein, but only HIT decreased total cholesterol. In addition, after 7âweeks of detraining, the lipid profile variables returned to baseline values. Additionally, 16âweeks of retraining with HIT or MT decreased blood glucose significantly. Moreover, MT and HIT training programmes in both periods improved cardiorespiratory fitness, but with 7âweeks of detraining, it returned to baseline values. CONCLUSION: Our data demonstrated the effectiveness of the inclusion of a MT or HIT programme as adjuvant therapy in hypertensive patients.
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Doenças Cardiovasculares , Hipertensão , Treinamento Resistido , Humanos , Doenças Cardiovasculares/prevenção & controle , Fatores de Risco , Exercício Físico/fisiologia , Hipertensão/terapia , Fatores de Risco de Doenças Cardíacas , LipídeosRESUMO
Introduction: Beta-alanine is a non-essential amino acid that has been a focus of increasing research by its role as ergogenic aid to improve muscle performance. Methods: A randomized, double-blind and controlled trial was conducted to determine the effect of a nutritional supplement of a sustained-release formulation of ß-alanine in recreational trained men. The active product was an innovative sustained-release ß-alanine microgranules powder blend, administered at high doses (15 g/day) divided into 3 intakes during 30 days. There were 10 participants in the experimental group and 9 in the placebo group, with a mean age of 22.5 ± 3.3 years. Participants were testing at baseline and at the end of study. Results: In the ß-alanine group, there were statistically increases in serum triglycerides, LDL-cholesterol, and urea nitrogen at the end of the study as compared with baseline, although there were no differences with the control group. The occurrence of paresthesia, described above all as tickling, was the majority but presented VAS score less than 3/10 in almost all subjects. Discussion: More studies are required to evaluate the changes in blood parameters that can be caused by high intake of ß-alanine during a long period of time. Clinical trial registration: ClinicalTrials.gov, identifier (NCT05334121).
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We compared the effect of two community-based physical activity (PA) programs on health-related quality of life (HRQL) and physical condition in people with cardiovascular risk factors. Fifty-one subjects participated in the "ACTIVA Murcia" AM3 program characterized by non-individualized training loads for 3 months, and forty-two participated in the AM6 program characterized by individualized progressive training loads for 6 months. Both programs included a 6-month follow-up period without PA. HRQL was assessed with the Short Form 36 Health Survey (SF-36) and physical condition by VO2 max, strength, flexibility, and balance. Participants in the AM6 program as compared with those in the AM3 program showed significantly higher scores in the subscales of physical functioning, mental health, energy/vitality, and general health. Mental health and general health at 6 months of follow-up were also scored significantly higher by AM6 participants. VO2 max and flexibility improved more in the AM6 group, whereas strength was better in the AM3 group. Half of the participants in the AM6 program expressed a strong willingness to continue exercising vs. 38% in the AM3 program. In this study, a community-based PA program with individualized progressive training loads of 6-month duration showed a more favorable impact on HRQL than a 3-month non-individualized PA program.
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Carlos Contreras was not included as an author in the published article [...].
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PURPOSE: To examine the acute and chronic effects of 10-weeks of progressive resistance training on sleep quality and sleeping heart rate variability in persons with Multiple Sclerosis (pwMS). METHODS: Eighteen pwMS (age = 44.8 ± 10.6 years; EDSS = 3.1 ± 1.7) completed a 10-week of resistance training, with three training sessions per week. Each session consisted of 4 lower body exercises, performing 2-4 sets of each exercise, with 8-15 repetitions each set, at an intensity ranging from 60 to 75% of 1-repetition maximum. Subjective and actigraphic sleep quality and sleeping heart rate variability were carried out at 4 different times: (1) Before the starting of the intervention on a rest day; (2) the night after training week 1 (3) the night after training week 10 and 4) after completing the resistance training program on a rest day. RESULTS: Regarding subjective sleep quality, significant main effects were observed on the variables of sleep quality, sleep comfort, easy of falling sleep, easy of waking up and felling of rest. Sleep quality, sleep comfort and easy of falling sleep were greater in rest night in week 1 vs. rest night in week 10. Actigraphic sleep quality also improved after the training program (rest night in week 1 vs. rest night in week 10). In the pair-wise comparison showed an acute effect in the session after the training program (rest night in week 10< training night in week 10) on HF, pNN50 and RMMSD. CONCLUSIONS: Resistance training is a non-pharmacological treatment that has the capacity to improve the regulation of autonomic system and, consequently, the sleep quality in pwMS.Implications for rehabilitation10 Weeks of resistance training improves the sleep quality of persons with multiple sclerosis.Resistance training can modulate autonomic cardiac control in this population.Improving the sleep quality is essential for persons with MS because of its close relationship to other variables, such as symptomatic fatigue.
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Esclerose Múltipla , Treinamento Resistido , Adulto , Sistema Nervoso Autônomo , Frequência Cardíaca/fisiologia , Humanos , Pessoa de Meia-Idade , Qualidade do SonoRESUMO
OBJECTIVE: In this pilot clinical study we investigated the effect on blood pressure (BP) of two community-based exercise training programs of high (HIT) vs. low-moderate intensity (LMIT) in hypertensive individuals receiving at least one antihypertensive drug. METHODS: The study included two phases of physical exercises based on 1-h session, 3 days/week for 12 and 16 weeks, respectively, separately by a 7-week resting period. Each phase was preceded by a four-week conditioning training period. According to the average maximal heart rate at baseline, participants were randomized to HIT (80-90%), LMIT (50-70%) or no-exercise (control). Heart rate was monitored during workout and BP profiles were registered by ambulatory BP monitoring at the beginning and end of each phase. RESULTS: Of 60 individuals randomized, 44 completed the study (HIT, n = 10; LMIT, n = 16; controls, n = 18). BP levels were significantly reduced after the second phase for both LMIT (SBP -3.1 mmHg, DBP -2.4 mmHg) and HIT (SBP -10.8 mmHg, DBP -8.3 mmHg). Similar levels of improvement were also found in daytime and night-time BP. Mean attendance of the prescribed training sessions was 87.4 ± 6.2% for HIT and 87.4 ± 5.3% for LMIT during the first phase and 84.1 ± 5.0% and 85.2 ± 5.9% during the second phase, respectively (p = 0.047). CONCLUSION: Both HIT and LMIT exercise training programs reduced BP but the HIT modality showed a lower rate of compliance with proposed training schedule. Intensity of training should be individually prescribed to improve tolerance to more high intensity exercises.
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BACKGROUND: ß-Alanine is a sport supplement with increasing popularity due to its consistent ability to improve physical performance, with the downside of requiring several weeks of supplementation as imposed to the maximum daily and single dose tolerated without side effects (i.e., paresthesia). To date, the only alternative to overcome this problem has been use of a sustained-release tablet, while powders are the most commonly used format to deliver several grams of amino acids in a single dose. In this study we assessed the bioavailability, pharmacokinetics and paresthesia effect of ß-alanine after administration in a novel controlled-released powder blend (test) versus a sustained-release tablet (reference). METHODS: Twelve subjects (25.6 ± 3.2 y, 50% female) participated in a randomized, single-blind, crossover study. Each participant was administered orally the test (ß-alanine 8 g, l-histidine 300 mg, carnosine 100 mg) or the reference product (10 tablets to reach ß-alanine 8 g, Zinc 20 mg) with a 1-week washout period. ß-Alanine plasma concentrations (0-8 h) were determined by LC-MS/MS and model-independent pharmacokinetic analysis was carried out. Paresthesia intensity was evaluated using a Visual Analog Score (VAS) and the categorical Intensity Sensory Score (ISS). RESULTS: The CMAX and AUC0â∞ increased 1.6- and 2.1-fold (both p < 0.001) in the test product, respectively, which yielded 2.1-fold higher bioavailability; Ka decreased in the test (0.0199 ± 0.0107 min-1) versus the reference (0.0299 ± 0.0121 min-1) product (p = 0.0834) as well as V/F and Cl/F (both p < 0.001); MRT0âlast increased in the test (143 ± 19 min) versus reference (128 ± 16 min) formulation (p = 0.0449); t1/2 remained similar (test: 63.5 ± 8.7 min, reference: 68.9 ± 9.8 min). Paresthesia EMAX increased 1.7-fold using the VAS (p = 0.086) and the ISS (p = 0.009). AUEC increased 1.9-fold with the VAS (p = 0.107) and the ISS (p = 0.019) reflecting scale intrinsic differences. Pharmacokinetic-pharmacodynamic analysis showed a clockwise hysteresis loop without prediction ability between CMAX, AUC0â∞ and EMAX or AUEC. No side effects were reported (except paresthesia). CONCLUSIONS: The novel controlled-release powder blend shows 100% higher bioavailability of ß-alanine, opening a new paradigm that shifts from chronic to short or mid-term supplementation strategies to increase carnosine stores in sports nutrition.
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Supplementation with ß-alanine is becoming a common practice in high-performance athletes. The purpose of the present study was to investigate the effects of a one-week high-dose ß-alanine loading phase employing a sustained-release powder on preserving the time-trial performance capacity of world tour cyclists during overreaching training. Per day, 20 g of sustained-release ß-alanine was administered during one week (7 days) of intensive team training camp in a randomised balanced placebo-controlled parallel trial design, with six participants in each ß-alanine (BA) or placebo (PLA) group. A 10-min time trial (10' TT) was carried out to analyse performance and biochemical variables. Anthropometry, paresthesia, and adverse event data were also collected. Power-based relative training load was quantified. Compared to placebo, the BA improved mean power (6.21%, 37.23 W; 95% CI: 3.98-70.48 W, p = 0.046), distance travelled (2.16%, p = 0.046) and total work (4.85%, p = 0.046) without differences in cadence (p = 0.506) or RPE. Lactate (p = 0.036) and anion gap (p = 0.047) were also higher in the BA group, without differences in pH or Bicarbonate. High daily and single doses were well tolerated. One-week high-dose ß-alanine loading with a sustained-release powder blend can help attenuate 10' TT performance losses of world tour cyclists due to intensive training.
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Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Suplementos Nutricionais , beta-Alanina/administração & dosagem , Adulto , Método Duplo-Cego , Humanos , Masculino , Pós , Adulto JovemRESUMO
The aim of a 12-week randomized double-blind placebo-controlled study was to assess the effect of daily supplementation with a natural extract of Spinacia oleracea L. (4 × 500 mg capsules/day; total 2 g per day) combined with a moderate-intensity training program (1 h session/3 times a week) on skeletal muscle fitness in adults over 50 years of age. Muscle strength assessed by isokinetic and isometric dynamometry improved significantly in the experimental (n = 23) and the placebo (n = 22) groups, but the magnitude of improvement was higher in the experimental group, with between-group differences in almost all variables, including isokinetic at 60° s-1 in knee extension, peak torque (p < 0.007); total work per repetition maximum (p < 0.009); isokinetic at 180°s-1 in knee extension, peak torque (p < 0.002); total work (p < 0.007); total work per repetition maximum (p < 0.005); average power (p < 0.027); isometric in knee extension, peak torque (p < 0.005); and average peak torque (p < 0.002). Similar findings were observed for muscle quality. Changes in quality of life (SF-36) were not found, except for improvements in the role physical (p < 0.023) and role emotional (p < 0.001) domains, likely as a result of the physical training sessions. A nutritional survey did not revealed changes in dietary habits. No adverse events were recorded. In subjects over 50 years of age, moderate-intensity strength training combined with daily supplementation for 12 weeks with a natural extract of Spinacia oleracea L. improved muscle-related variables and muscle quality. Maintaining muscle health is a key component of healthy aging.
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Suplementos Nutricionais , Força Muscular/efeitos dos fármacos , Músculo Esquelético/fisiologia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Sarcopenia/prevenção & controle , Spinacia oleracea/química , Fatores Etários , Idoso , Método Duplo-Cego , Feminino , Envelhecimento Saudável/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Fitoterapia , Sarcopenia/fisiopatologia , Fatores de TempoRESUMO
Due to COVID-19, wearing a face mask to reduce virus transmission is currently mandatory in some countries when participants practice exercise in sports centers. Therefore, the aim of the present study was to analyze the effect of wearing a surgical or FFP2 mask during a resistance training session. Fourteen people with sarcopenia (age: 59.40 ± 5.46 years; weight: 68.78 ± 8.31 kg; height: 163.84 ± 9.08 cm) that participated in the study performed three training sessions in a randomized order: 4 sets of 10 repetitions of a half-squat at 60% of the one-repetition maximum and 90 s of rest between set and were either (a) without a mask (NM), (b) wearing a surgical face mask (SM), and (c) wearing a FFP2 face mask (FFP2). We found that wearing face masks had no effect on strength performance (session mean propulsive velocity (m/s): WM: 0.396 ± 0.042; SM: 0.387 ± 0.037; and FFP2: 0.391 ± 0.042 (p = 0.918)). Additionally, no impact of wearing a mask was found on heart rate, heart rate variability, blood lactate concentration (WM: 4.17 ± 1.89; SM: 4.49 ± 2.07; and FFP2: 5.28 ± 2.45 mmol/L (p = 0.447)), or rating of perceived exertion. Wearing a surgical or FFP2 face mask during a resistance training session resulted in similar strength performance and physiological responses than the same exercise without a mask in persons with sarcopenia.
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A randomized, double-blind, placebo-controlled study was conducted with the primary objective of assessing the effect of a natural extract of Sclerocarya birrea on glucose metabolism in subjects with prediabetes. The duration of the study was 90 days. Thirty-three subjects assigned to the experimental group (daily ingestion of 100 mg of the nutraceutical product) and 34 assigned to the placebo group completed the study. There were 36 men and 31 women with a mean age of 32.3 ± 14.1 years. In the area under the curve (AUC) of the oral glucose tolerance test (OGTT), statistically significant decreases in the experimental group at 40 and 90 days as compared with baseline were found, whereas significant changes in the placebo group were not observed. Within-group differences were statistically significant in favor of the experimental group for glucose peak at OGTT, serum insulin, insulin resistance markers, and flow-mediated dilation. Changes in lipid and anthropometric parameters were not observed, although there was a trend for lower cholesterol levels and a decrease in body weight in the experimental group. Decreases in systolic blood pressure were also higher among subjects in the experimental group. This exploratory study confirms the antidiabetic activity of Sclerocarya birrea in prediabetes. Further studies using better measurements of beta-cell function are needed to clarify the underlying mechanisms of the hypoglycemic effect of this natural compound.
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Anacardiaceae , Suplementos Nutricionais , Hipoglicemiantes/administração & dosagem , Extratos Vegetais/administração & dosagem , Estado Pré-Diabético/terapia , Adulto , Área Sob a Curva , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Método Duplo-Cego , Feminino , Teste de Tolerância a Glucose , Controle Glicêmico/métodos , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/sangueRESUMO
This randomized double-blind and controlled single-center clinical trial was designed to evaluate the effect of a 6-week intake of a probiotic product (1 capsule/day) vs. a placebo on an oxidative stress model of physical exercise (high intensity and duration) in male cyclists (probiotic group, n = 22; placebo, n = 21). This probiotic included three lyophilized strains (Bifidobacterium longum CECT 7347, Lactobacillus casei CECT 9104, and Lactobacillus rhamnosus CECT 8361). Study variables were urinary isoprostane, serum malondialdehyde (MDA), serum oxidized low-density lipoprotein (Ox-LDL), urinary 8-hydroxy-2'-deoxiguanosine (8-OHdG), serum protein carbonyl, serum glutathione peroxidase (GPx), and serum superoxide dismutase (SOD). At 6 weeks, as compared with baseline, significant differences in 8-OHdG (Δ mean difference -10.9 (95% CI -14.5 to -7.3); p < 0.001), MDA (Δ mean difference -207.6 (95% CI -349.1 to -66.1; p < 0.05), and Ox-LDL (Δ mean difference -122.5 (95% CI -240 to -4.5); p < 0.05) were found in the probiotic group only. Serum GPx did not increase in the probiotic group, whereas the mean difference was significant in the placebo group (477.8 (95% CI 112.5 to 843.2); p < 0.05). These findings suggest an antioxidant effect of this probiotic on underlying interacting oxidative stress mechanisms and their modulation in healthy subjects. The study was registered in ClinicalTrials.gov (NCT03798821).
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BACKGROUND: Fish oils were studied as ergogenic aids in a number of mixed physical trial designs showing promising results. However, the heterogeneous purity of the studied supplements, combined with the variety of physical tests employed call for more studies to confirm these findings, ideally with standardised supplements. Our aim was to test a supplement highly concentrated in DHA (DHA:EPA ratio equal to approximately 8:1) on a maximal cycling test to elucidate performance improvements mainly due to DHA. METHODS: A double-blind, placebo controlled, randomised balanced, parallel design, in competitive amateur cyclists was employed. They were all male, older than 18 years old, with training routine of 2 to 4 sessions per week lasting at least one hour each. A ramp cycling test to exhaustion with a subsequent 5 min recovery phase was employed before and after treatment to analyse aerobic metabolism and lactate clearance after the bout. After 30 days of supplementation with 975 mg of re-esterified DHA, the thirty-eight cyclist who completed the study were finally included for statistical analysis. RESULTS: Mean power output at ventilatory threshold 2 (VT2) improved after DHA supplementation both as absolute (â³DHA versus â³PLA: 6.33-26.54 Watts; CI 95%) and relative (p=0.006) values, paralleled with higher oxygen consumption at VT2 both for absolute (DHA 2729.4 ±304.5, 3045.9 ±335.0; PLA 2792.3 ±339.5, 2845.5 ±357.1; ml·min-1 baseline versus post p=0.025) and relative values (DHA 36.6 ±5.0, 41.2 ±5.4; PLA 37.2 ±5.7, 38.1 ±5.2; ml·kg-1·min-1 baseline versus post p=0.024). Heart rate recovery rate improved during the recovery phase in the DHA group compared to PLA (p=0.005). CONCLUSION: DHA is capable of improving mean power output at the ventilatory threshold 2 (anaerobic ventilatory threshold) in amateur competitive cyclists. It is unclear if these findings are the result of the specific DHA supplement blend or another factor.
Assuntos
Limiar Anaeróbio/fisiologia , Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Comportamento Competitivo/fisiologia , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Substâncias para Melhoria do Desempenho/administração & dosagem , Adulto , Ácidos Docosa-Hexaenoicos/metabolismo , Método Duplo-Cego , Esterificação , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Consumo de Oxigênio , Substâncias para Melhoria do Desempenho/metabolismoRESUMO
Cardiovascular disease is one of the leading causes of death globally, and cardiovascular risk factors (CRFs) are major behavioral risk factors. Therefore, community-based programs are being designed based on the prescription of physical exercise from primary care centers to improve people's health through changes in lifestyle. The objective was to compare the effects of two types of community exercise on adherence, lipid profile, body composition and blood pressure. A prospective observational cohort study was designed with two cohorts of study depending on the duration and type of physical exercise program performed. Fifty-one participants (82.4% women) with CRF completed the observation period in which they carried out a short-term, non-individualized exercise program (3 months), and 42 participants (71.4% women) with CRF completed the observation period in which they conducted a long-term, individualized exercise program (6 months). The results suggest that participants who carried out the longer program with an individualized progression produced greater adherence to physical exercise and a decrease in diastolic blood pressure. In addition, LDL and insulin levels decreased in both groups. Therefore, our results suggest that a longer duration and individualized evolution of the loads of a community exercise program lead to higher levels of physical activity (PA) and improvements diastolic blood pressure.