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1.
J Int Soc Sports Nutr ; 19(1): 1-16, 2022.
Article in English | MEDLINE | ID: mdl-35599921

ABSTRACT

Objective: This study examined the effects of short-term betaine supplementation on muscle endurance, plasma lactate, testosterone and cortisol levels, and the testosterone to cortisol (T/C) ratio in response to acute resistance exercise (RE). Method: Using a double-blind, crossover study design, 10 handball players (age ± SD = 16 ± 1 yrs) without prior-structured RE experience performed a high-intensity RE session (leg press followed by bench press; 5 sets to volitional fatigue using 80% baseline 1 repetition maximum (1RM)), before and after 14 days of either placebo (maltodextrin) or betaine (2.5 g·d-1) supplementation. A 30-day washout period separated each treatment. 48 h prior to testing sessions, participants recorded their food intake and did not perform strenuous exercise. Venous blood was sampled before supplementation, and before and after each RE session. Results: After betaine supplementation, participants performed more repetitions (p < 0.001) during the leg press (Betaine: 35.8 ± 4.3; Placebo: 24.8 ± 3.6, Cohen's d = 2.77) and bench press (Betaine: 36.3 ± 2.6; Placebo: 26.1 ± 3.5, Cohen's d = 3.34). Betaine resulted in lower post-exercise cortisol (Betaine: 7.6 ± 1.7; Placebo: 13 ± 3.4 µg.dL-1, p = 0.003, generalized eta squared ( η G 2 ) = 0.49) and lactate (Betaine: 5.2 ± 0.3; Placebo: 6 ± 0.3 mmol.L-1, p < 0.001, η G 2 = 0.96) and higher total testosterone (Betaine: 15.2 ± 2.2; Placebo: 8.7 ± 1.7 ng.mL-1, p < 0.001, η G 2 = 0.87) and T/C ratio (Betaine: 0.21 ± 0.05; Placebo: 0.07 ± 0.02, p < 0.001, = 0.82). Conclusions: Two weeks of betaine supplementation improved upper- and lower-body muscle endurance and influenced indices of endocrine function following an acute session of high-intensity RE in adolescent handball players.


Subject(s)
Betaine , Resistance Training , Adolescent , Athletes , Betaine/pharmacology , Cross-Over Studies , Dietary Supplements , Double-Blind Method , Humans , Hydrocortisone , Lactic Acid , Muscle Strength , Muscle, Skeletal , Testosterone
2.
PLoS One ; 17(3): e0264910, 2022.
Article in English | MEDLINE | ID: mdl-35294451

ABSTRACT

The present study aimed to propose a new multidimensional taekwondo-specific test to estimate aerobic power, anaerobic fitness, and agility. Out of sixty-five male volunteers, forty-six, forty-eight, and fifty athletes (18-35 years; black- and red-belt level) were included in the final analysis for aerobic, anaerobic, and agility assessments, respectively. Maximum oxygen uptake (VO2max, using a graded exercise test on a treadmill), anaerobic power (using the 30-s Wingate anaerobic test, WAnT), and agility performance (using the agility T-Test) were measured via non-specific laboratory and field tests across a two-week period. The taekwondo-specific aerobic-anaerobic-agility (TAAA) test comprised six 20-s intervals of shuttle sprints over a 4-m distance, and the execution of roundhouse kicks alternating the legs at the end of each distance, with 10-s rest intervals between the sets. The multiple linear regression revealed that the difference between heart rate (HR) after and 1 minute after the TAAA test (p < 0.001), and body mass index (BMI; p = 0.006) were significant to estimate VO2max. Likewise, there was a very large (R = 0.79) and large (R = 0.55) correlation between the average and maximum number of kicks performed in the TAAA test and the WAnT mean and peak power, respectively (p < 0.001). Moreover, a linear relationship was found between the T-Test and agility performance acquired in the TAAA test (R = 0.74; p < 0.001). The TAAA test can be considered a valid simple tool for monitoring VO2max, anaerobic fitness, and agility in male taekwondo athletes.


Subject(s)
Athletic Performance , Martial Arts , Anaerobiosis , Athletic Performance/physiology , Exercise Test/methods , Humans , Male , Martial Arts/physiology , Oxygen , Oxygen Consumption/physiology
3.
J Clin Hypertens (Greenwich) ; 23(5): 978-986, 2021 05.
Article in English | MEDLINE | ID: mdl-33491287

ABSTRACT

This study aimed to investigate the chronic effects of green tea (GT) extract and resistance training (RT) on ambulatory and office blood pressure (BP), heart rate (HR), and rate-pressure product (RPP) in a sample of Iranian women with high-normal/stage 1 hypertension. Forty-four middle-aged sedentary women participated in this randomized, double-blind, placebo-controlled study. They were randomly assigned to one of four groups: GT and RT (GR, n = 11), RT (n = 10), GT (n = 10), or control (n = 13). Three weeks of GT consumption were followed by six weeks of the interaction with RT. GR and RT groups performed two circuits of RT at %50 of 1RM two days per week. RT and control groups also received placebo (maltodextrin) with the same timing. The changes of each variable from baseline to post-intervention were compared between the groups using the ANOVA test, and effect size (ES) statistic was also calculated. In comparison with the control group, significant reductions were found for office systolic BP (SBP, 8%, ES = 1.22), and 24 h-SBP (5%, ES = 1.2) in the RT group. However, GR group showed significant decreases in office SBP (10.5%, ES = 1.45), mean BP (8%, ES = 1.11), RPP (13%, ES = 1.47), 24 h-SBP (5%, ES = 1.21), and 24 h-RPP (10%, ES = 1.15). The interaction of regular RT and GT consumption seems to induce more beneficial effects on some important parameters including MBP and RPP when compared to RT or GT alone.


Subject(s)
Hypertension , Resistance Training , Blood Pressure , Blood Pressure Monitoring, Ambulatory , Double-Blind Method , Female , Humans , Hypertension/diagnosis , Hypertension/drug therapy , Iran/epidemiology , Middle Aged , Tea
4.
Antioxidants (Basel) ; 9(9)2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32825755

ABSTRACT

The prevalence of waterpipe tobacco smoking (WTS), which is also known as ghalyan, shisha or hookah, is increasing rapidly around the world, especially among youth. Growing interest in this form of tobacco smoking can be traced, in part, to the use of flavored tobacco products, social acceptability as a safer option than cigarettes, and its consideration as a relaxation method or entertainment. However, there is a well-established association between WTS and oxidative stress that causes irreversible chronic pathological conditions such as cardiovascular and respiratory problems, as well as different types of cancers, and thus increases the risk of mortality. Clearly, induction of inflammation status through increased reactive oxygen species (ROS), which in turn leads to oxidative stress and harm to lipids, DNA, and proteins, is the most plausible mechanism to explain the potential harmful effects of WTS. Unlike WTS, well-designed exercise training programs increase ROS to the extent that it is beneficial to the body. In this study, we aimed to review available evidence on the impact of exercise training on oxidative stress and inflammation status. We also summarize the effect of acute and chronic WTS on different exercise capacities.

5.
Front Nutr ; 7: 570235, 2020.
Article in English | MEDLINE | ID: mdl-33521030

ABSTRACT

Fasting is one of the religious rituals of Muslims worldwide who refrain from eating foods and liquids every year during Ramadan. This year (2020), Ramadan is very different from previous years due to the outbreak of a terrible microscopic giant called coronavirus disease 2019 (COVID-19). The pandemic COVID-19 has made Ramadan very important this year because the virus has infected millions of people around the world and killed thousands, especially people with immunodeficiency. In dealing with COVID-19, maintaining good hygiene and supporting the immune system are effective, preventive approaches. Moderate exercise training and proper nutrition are the most important factors to support immune function. Lack of facilities, poor health and many traditions that lead to public community gatherings have made many Islamic countries susceptible to this dangerous virus. In such an unprecedented situation, there are many Muslims who doubt whether they can fast or not. Therefore, the proposal of usable exercise programs and effective nutritional strategies is imperative. In this study, we will look at the proposed health effects of fasting and its impact on the immune system, the effects of Ramadan intermittent fasting on resting values and responses of immunological/antioxidant biomarkers in elite and recreational athletes, together with the important health, nutrition, and exercise advice that fasting people need to follow in the event of a COVID-19 outbreak.

6.
J Women Aging ; 32(3): 279-291, 2020.
Article in English | MEDLINE | ID: mdl-30465635

ABSTRACT

The aim of the study was to evaluate the effects of an 8-week aerobic training in mineral geothermal water on hemodynamic variables, VO2max, and body composition in sedentary hypertensive women. Twenty postmenopausal women (58.55 ± 3.28 years) were divided into an exercise group (2 days/week, 30-40 minutes, 60%-75% of HRmax) and control group. Compared to the control group, a significant reduction in systolic blood pressure, heart rate, rate pressure product, body fat percent, and a significant improvement in VO2max values was found. Aerobic training in thermo-mineral spring water is a safe and effective training modality in the young-older hypertensive population.


Subject(s)
Exercise Therapy/methods , Exercise/physiology , Hypertension/therapy , Mineral Waters , Obesity/therapy , Steam , Case-Control Studies , Female , Humans , Hypertension/complications , Middle Aged , Obesity/complications , Physical Endurance/physiology , Treatment Outcome
7.
J Health Popul Nutr ; 38(1): 30, 2019 10 31.
Article in English | MEDLINE | ID: mdl-31672172

ABSTRACT

BACKGROUND: Changes in blood pressure (BP) may affect pain. However, the interaction effect of resistance training and green tea on BP and pain has not been studied. The primary aim of this study was to evaluate the impact of resistance training and green tea extract (GTE) on pain variables in hypertensive patients. Secondary aim included determining the effects of BP alterations on pain responses. METHODS: In a randomized, double-blind, placebo-controlled study, 30 middle-aged sedentary women were randomly divided into resistance training and green tea extract (GR, n = 8), resistance training (R, n = 8), green tea (G, n = 7), and control groups (C, n = 7). The study period consisted of 3 weeks of GTE (~ 245 mg total polyphenols) consumption twice a day followed by 6 weeks of interaction with resistance training. GR and R groups performed two circuits of training with ten repetitions at 50% of 1RM 2 days a week while other two groups had no any regular exercise training. R and C groups also received placebo capsules (maltodextrin) with the same timing. Pain threshold and perception, BP, and heart rate were recorded following the first and last session of training at rest and 5th and 15th minute. RESULTS: Pain perception of training groups after the last session was significantly higher than control conditions, and at this time, the magnitude of BP responses was lower in training groups. In proportion to pain threshold, there were no significant differences between groups. CONCLUSION: It seems that training-induced hypotension can alter pain perception in hypertensive women through changes in baroreceptor activation.


Subject(s)
Hypertension/therapy , Pain/physiopathology , Plant Extracts/administration & dosage , Resistance Training/methods , Tea , Adult , Blood Pressure/physiology , Double-Blind Method , Female , Humans , Hypertension/complications , Hypertension/physiopathology , Middle Aged , Pain/etiology , Pain Management/methods , Sedentary Behavior , Treatment Outcome
8.
Antioxidants (Basel) ; 8(10)2019 Sep 20.
Article in English | MEDLINE | ID: mdl-31546982

ABSTRACT

Waterpipe tobacco (WPT) smoking is a public health problem with similar or even stronger effects than cigarette smoking. Although it appears to be associated with extensive oxidative stress, there is a limited number of studies on the oxidative effects of WPT smoking in stressful conditions. We, therefore, compared the responses of salivary flow rate (SFR), uric acid (UA) concentration, and peroxidase (POX) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) activities between WPT smokers and non-smokers following a bout of exhaustive aerobic exercise (AE). Twenty-three sedentary young women (age: 22.95 ± 2.83 years) participated in this study, including 11 smokers (7.00 ± 1.41 uses/week) and 12 non-smokers. All participants were required to perform the Bruce protocol treadmill test at an initial gradient of 10% at 1.7 mph, with increases of these parameters every 3 min until exhaustion. Unstimulated saliva samples were collected before, immediately after, and 1 hour after AE. WPT smokers showed lower SFR compared with non-smokers at all time points (p < 0.05). In comparison to WPT smokers, a larger increase in POX activity (approximately 23% vs. 14%; p = 0.009) and a smaller decline in DPPH activity (approximately -8% vs. -15%; p = 0.004) were found in non-smokers compared with WPT smokers. While these changes were slowly compensated within 1 hour after exhaustion, the activity of both markers was different from the pre-exercise values (p < 0.001). There was also a trend for UA concentration in non-smokers to be higher during the recovery period, with no significant difference between the groups (p > 0.05). It seems that WPT smoking is associated with negative effects on important human antioxidants and a diminished antioxidative response following acute exercise.

9.
Antioxidants (Basel) ; 7(10)2018 Oct 20.
Article in English | MEDLINE | ID: mdl-30347824

ABSTRACT

ß-hydroxy ß-methylbutyrate (HMB) is a bioactive metabolite formed from the breakdown of the branched-chain amino acid, leucine. Given the popularity of HMB supplements among different athletes, specifically, those who participate in regular resistance training, this review was performed to summarize current literature on some aspects of HMB supplementation that have received less attention. Because of the small number of published studies, it has not been possible to conclude the exact effects of HMB on cardiovascular parameters, oxidative stress, and inflammatory markers. Thus, the interpretation of outcomes should be taken cautiously. However, the data presented here suggest that acute HMB supplementation may attenuate the pro-inflammatory response following an intense bout of resistance exercise in athletes. Also, the available findings collectively indicate that chronic HMB consumption with resistance training does not improve cardiovascular risk factors and oxidative stress markers greater than resistance training alone. Taken together, there is clearly a need for further well-designed, long-term studies to support these findings and determine whether HMB supplementation affects the adaptations induced by resistance training associated with the body's inflammatory condition, antioxidative defense system, and cardiovascular risk factors in humans.

10.
J Sports Med Phys Fitness ; 56(10): 1132-1138, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26376618

ABSTRACT

BACKGROUND: Smoking is known as a serious global public health problem, and is also an important risk factor for oral diseases and cause of oxidative stress and cellular damage. Saliva is the first biological medium encountered during inhalation of cigarette smoke. Additionally, previous studies demonstrated that exhaustive aerobic exercise could increase oxidative stress and cellular damage. Therefore, the main aim of this study was to compare the response of salivary antioxidants (peroxides (POX), uric acid (UA), 1-1dipheny l-2-picrylhydrazyl hydrate (DPPH) of exhaustive aerobic exercise between healthy smoker and non-smoker young girls. METHODS: Ten smokers and 10 non-smokers were enrolled for this study. Subjects performed a progressive cycle ergometer with an initial load of 50 W that was increased 50Wevery 3 minutes at the speed of 60rpm, until exhaustion. Un-stimulated saliva samples were collected before, immediately and 1 hour after exercise. RESULTS: The results showed that POX activity and UA concentration significantly increased immediately after exercise in both groups when compared to the pre exercise values (P<0.01). The level of salivary POX of non-smokers were greater than smokers immediately after exercise (P<0.01). Aerobic exercise caused a decrease in salivary DPPH activity immediately and 1 h after exercise in both groups (P<0.01). When the DPPH values were compared between smoker and non-smoker subjects, a significant decrease was observed in smokers immediately and 1 h after exercise (P<0.01). CONCLUSIONS: In conclusion, aerobic exercise was induced oxidative stress in both groups but oxidative stress in smoking females was greater.


Subject(s)
Antioxidants/analysis , Biomarkers/analysis , Exercise/physiology , Oxidative Stress/physiology , Saliva/chemistry , Smoking , Adult , Female , Humans , Uric Acid , Young Adult
11.
High Blood Press Cardiovasc Prev ; 21(3): 213-9, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24619865

ABSTRACT

INTRODUCTION: Resistance exercise (RE) may lead to a post-exercise hypotension (PEH) response. Previous studies showed that green tea (GT) and its polyphenols, especially Epigallocatechin-3-gallate (EGCG) may have a favorable effect on blood pressure (BP). AIM: We investigated the green tea extract (GTE) effects on BP, heart rate (HR), and rate pressure product (RPP) responses to a low-intensity RE in hypertensive women. METHODS: Middle-aged women (n = 24, 46.4 ± 6.3 years old; 66.6 ± 9.2 kg; 166.3 ± 4.2 cm) were randomly assigned into three groups of eight persons. GTE consumption group (T) and RE group (R), respectively, ingested GTE (~75 mg EGCG) and placebo (PL; maltodextrin) capsules two times a day for three weeks and then completed 2 circuits of six RE using 50% one repetition maximum (1RM). Patients of control group (C) just ingested PL and rested in a non-exercise control trial. BP, HR and RPP were measured prior and post-exercise at 0, 15, 30, 45, and 60 min. RESULTS: The repeated measures analysis of variance (ANOVA) revealed that there were no significant alterations for arterial BP, HR and RPP of C group. HR of T and R groups was increased immediately after RE. A significant fall of systolic BP (SBP) and diastolic BP (DBP) occurred in both T and R groups for 60 min post-exercise compared to resting values. Mean arterial BP (MAP) and RPP decreased significantly after RE in both exercise groups from 15 to 60 min. During 45 and 60 time points, T group had a lower RPP values than C group. The differences between T and R groups were only MAP at 0 and 15 time points. CONCLUSIONS: Three weeks of GTE ingestion did not influenced SBP, DBP and HR but may be have a favorable effect on MAP and RPP responses to an acute RE during 1 h recovery of exercise.


Subject(s)
Antioxidants/pharmacology , Heart Rate/drug effects , Hypertension/physiopathology , Plant Extracts/pharmacology , Tea , Adult , Analysis of Variance , Blood Pressure/drug effects , Blood Pressure/physiology , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/physiopathology , Catechin/analogs & derivatives , Catechin/pharmacology , Dose-Response Relationship, Drug , Female , Heart Rate/physiology , Humans , Hypertension/complications , Hypertension/drug therapy , Middle Aged , Resistance Training , Risk Factors , Treatment Outcome
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