Category: Home

Green tea extract and sports performance

Green tea extract and sports performance

examined the Speed optimization services of drinking green tea extrqct moderate-intensity exercise and extrat that concomitant Topical antifungal remedies for athletes foot of the two Topical antifungal remedies for athletes foot increased metabolism of fat, which was the predominant fuel during exercise [ 44 ]. Apex has the perfect blend of both. Results of neuromuscular electrical activity obtained from GTE and placebo groups during the cycling trials with and without fatigue condition.

Green tea extract and sports performance -

This is the case of ultra-marathons, trail running, cycling distance challenges, and professional or amateur cycling tours Lucia et al. Therefore, strategies to minimize the fatigue effects on performance of repeated bouts of exercise are of interest for both coaches and athletes.

A plausible strategy to achieve this purpose is to promote a faster exercise recovery. In this regard, supplementation with natural products has attracted interest of athletes from different competitive levels. Considering that fatigue and its effects on performance during repeated sessions of exercise have important participation of oxidative stress and muscle damage Kyparos et al.

GTE is rich in polyphenols including epigallocatechin gallate, epicatechin, epigallocatechin, and epicatechin gallate, which result in a powerful antioxidant activity Jowko, ; Schimidt et al. Previous studies showed that GTE supplementation might reduce oxidative stress Sugita et al.

Furthermore, GTE can reduce muscle soreness resultant of eccentric exercise Herrlinger et al. Similar effects were not found when a single-dose of GTE was intake before intense muscle-endurance tests Jowko et al.

The effects described for GTE supplementation on muscle damage and oxidative stress suggest that GTE could be a valid strategy to preserve performance during repeated bouts of exercise leading to a cumulative fatigue. To the best of our knowledge, our study is the first to address this question.

The potential effect of GTE supplementation on performance under a fatigue state has important practical applications. For instance, amateur competitions can involve consecutive days racing without a proper time for recovery Shing et al.

Therefore, the main goal of our study was to determine whether GTE supplementation minimizes muscle damage and oxidative stress contributing to the preservation of neuromuscular function in trained athletes exposed to consecutive sessions of exercise leading to cumulative fatigue.

We performed a randomized triple blinded placebo control experiment. Upon start of the study, 22 healthy trained men were recruited, but 16 completed all the phases of the study and had the data included in the analysis.

The competitive level included participation in state and national competitions. During the study participants were requested to avoid ingestion of any medicine or stimulants, and to keep their regular routine of training and diet. They should inform the need to start any medical treatment during the entire experimental phase.

Six participants were excluded due to these criteria and therefore we had eight participants in each group. Intervention group was supplemented with green tea extract and the control received capsules with placebo.

Table 1 describes the study participants. Experiments started with the participants completing an incremental maximal cycling test to determine the individual peak power output PPO.

In the following days they performed submaximal cycling trials combined or not with sessions of knee extension exercise to fatigue. The whole experiment lasted 23 days for each participant. In the different visits to the laboratory, neuromuscular parameters were determined based on electrical neuromuscular activity; muscle damage and oxidative stress were determined from blood samples; and a cardiac monitor recorded heart rate.

Data were compared between the GTE and placebo groups and between the conditions with or without the fatigue. All participants were evaluated with or without fatigue.

In the case of non-fatigue condition, we ensured at least 5 days without supplementation and without performance of vigorous exercise Chow et al. We call fatigue the condition of being tested after completing knee extension trials until exhaustion in two consecutive days before a submaximal cycling trial.

Figure 1 illustrates our experimental design. All participants signed a consent term before starting participation in the study; procedures were conducted in agreement with declaration of Helsinki, and this research was approved by the institutional committee of ethics in research IRB no.

FIGURE 1. Experimental design. All participants completed the same protocols. Experiment started with the incremental maximal test to determine peak power output PPO. In the last 3 days of supplementation participants repeated the submaximal cycling trial after two sessions of knee extensors exercise to fatigue.

To avoid learning effects from the first test on the results after fatigue condition, half of the participants from each group performed the non-fatigue submaximal cycling test after the fatigue period, and the other half before.

rpm: cadence, in revolution per minute, PPO: PPO, EMG: record of electrical muscle activation by surface electromyography, RVL: vastus lateralis from right leg, left vastus lateralis LVL : vastus lateralis from left leg.

Cycling trials were performed always between 3 and 6 pm on a cycle ergometer Lode Excalibur Sport, Lode, Netherlands properly adjusted to the individual body posture of the participants.

The last workload completed was therefore named the PPO Priego Quesada et al. Neuromuscular electrical activity was determined during the submaximal cycling tests using surface electromyography EMG. EMG signals were recorded bilaterally from the vastus lateralis, which was selected due to its main role for power production in cycling Bini et al.

Data were sampled at 1. EMG signals were filtered using a band-pass digital Butterworth filter with cut off frequency of 0. Onset and offset of neuromuscular electrical activity for each contraction burst were determined using the criteria of variation of two standard deviation for increase and decrease considering the average activation recorded during rest Hodges and Bui, From each contraction burst during the cycling trials, the root mean square RMS value was determined as an indicator of magnitude of activation Moritani et al.

At the end, for each participant we had five moments of 5-min EMG record. EMG data from moment 1 5—10 min of exercise was considered the reference to the normalization of RMS values obtained during the exercise.

We aimed to elicit a condition of cumulative fatigue by combining 2 days of strenuous knee extension exercises until exhaustion and the performance of a submaximal cycling trial on the subsequent day. The trials for knee extension were also performed between 3 and 6 pm using a seated knee extensor machine with the participant performing concentric-eccentric knee extensions until exhaustion.

A metronome set at 20 beats per minute controlled the movement velocity. In the first set of repetitions the maximal number of voluntary repetitions was determined. Cycling trial was performed 24 h after the second fatigue protocol.

Participants received 15 capsules not identified and were advise to intake one capsule per day, before breakfast, with a glass of water. The capsules from GTE and placebo groups were identical.

Supplementation was administrated in capsules because this strategy results in larger bioavailability Henning et al. Capsules content were GTE and celulomax E, an inactive excipient that served as a placebo. GTE dose was defined considering the results from a previous study in which the same supplementation dose reduced fatigue-induced muscle damage da Silva et al.

GTE was purchased from a local commercial supplier, manipulated by a pharmaceutics registered professional, and tested using high performance liquid chromatography HPLC to ensure the presence of epigallocatechin gallate 1.

HPLC was performed with a Shimadzu Prominence Auto Sampler YL system Shimadzu, Kyoto, Japan , equipped with Shimadzu YL reciprocating pumps connected to an YL degasser with an YL integrator, and YL diode array detector. To determine compounds profile the extracts were analyzed using a reversed phase carried out under gradient conditions using Synergi Fusion-RP 80A column 4.

A flow rate of 0. Phenolic compounds were identified and quantified by comparing the retention time and UV—Visible spectral data to known previously injected standards. The chromatography peaks were confirmed by comparing the retention time with those of reference standards and by DAD spectra.

All chromatography operations were performed at ambient temperature and in triplicate. During the supplementation period participants were requested to report any consume of stimulants, other supplements, medications, and teas originated from C.

sinensis or other plant. Furthermore, they were requested to avoid consume of fruits, milk, caffeine, and alcohol on the day before each cycling tests when blood samples were collected Sugita et al.

Participants received daily messages to recall them about the orientations and to avoid mistakes in capsules intake. Blood samples 10 mL were collected from the ulnar vein before and after each cycling submaximal test.

Samples were centrifuged 10 min, rpm to separate the plasma that was stored at °C to further determination of total activity of creatine kinase CK Noakes, using enzymatic commercial kits Labtest. The blood samples for biochemical analyzes of oxidative damage were collected in tubes with heparin.

The analysis of substances reactive to the thiobarbituric acid TBARS served to determine the lipid peroxidation Ohkawa et al. To ensure that participants had no damage in soft tissues that could increase CK for instance, a muscle strain, tendon, or ligament injury, etc.

we determined the serum levels of the C reactive protein Pritchett, using immunological kits Labtest. The blood analyses are named in the result section as: A pre cycling without fatigue, B post-cycling without fatigue, C pre cycling with fatigue, and D post-cycling with fatigue.

Data are expressed as mean and standard deviation. Normality of data distribution was confirmed using the Shapiro—Wilk test. EMG signals within cycling trials were compared between the moments by one-way ANOVA with Bonferroni post hoc , and the comparison between the groups and fatigue conditions by two-way ANOVA with Bonferroni post hoc.

Biochemical and heart rate data were compared within cycling trials by one-way ANOVA with Bonferroni post hoc. For non-parametric data Friedman and Wilcoxon testes were used.

Comparisons between the groups were performed using independent t -test. Significance level was set at 0. Results of C-reactive protein suggest that participants from GTE and placebo groups did not suffer macro injuries related to the experiments data not shown.

Muscle damage was lower in the GTE supplemented participants. FIGURE 2. Plasma A creatine kinase CK and B plasma lipid peroxidation measured by thiobarbituric acid reactive substances TBARS. Placebo group showed higher oxidative stress in the fatigue condition, suggesting a protective role of GTE supplementation.

Cardiovascular responses estimated by heart rate showed that GTE supplemented group experienced lower cardiac workload than placebo group. Heart rate responses to the cycling trials Figure 3 were analyzed by the angular coefficient of the regression curve considering second-to-second data recorded during the exercise.

FIGURE 3. Heart rate HR curve slope over time of exercise in the different groups and conditions. Neuromuscular activation from the left vastus lateralis LVL of the participants of placebo group showed significant impairment in the fatigue condition.

FIGURE 4. Results of neuromuscular electrical activity obtained from GTE and placebo groups during the cycling trials with and without fatigue condition. Data are shown as mean bars and standard deviation vertical lines for A root mean square RMS and B median frequency MDF normalized to the moment 1 for right RVL and left vastus lateralis LVL.

Here we set out to determine whether GTE supplementation could benefit performance under a condition of cumulative fatigue. GTE has been shown as a potential antioxidant, with positive effects on different tissues, and could be a good option for competitive sports. Despite of its popularity among athletes, few evidences of the benefits are available concerning amateur competitive sport.

To the best of our knowledge, this is the first study demonstrating that GTE supplementation before cumulative fatigue minimizes muscle damage and oxidative stress in trained athletes, therefore playing a significant role in exercise recovery, and with important effects on neuromuscular and cardiovascular performance during exercise.

Previous studies on GTE supplementation in athletes were limited to the determination of performance improvement resultant of higher lipid oxidation due to GTE activity Ichinose et al.

Rather than an effect on energy supply, here we focused on performance during endurance trials of cycling under cumulative fatigue, which is close to the experienced by athletes in competitions lasting more than 1 day, and found GTE results supporting benefits of this supplementation on both muscle damage and recovery markers, as well neuromuscular function Fuglevand et al.

These are important implication for training and competition. Placebo group showed higher muscle damage after fatigue. Increase in CK activity is commonly associated with damage resultant of mechanical stress and structural acute changes in the muscle, which happens in coexistence with increase in oxidative stress Morillas-Ruiz et al.

Such result supports the role of GTE in minimizing muscle damage resultant of exercise. Oxidative stress is the most accepted explanation to the presence of muscle damage, and the results from GTE group support the lower oxidative stress as an explanation to the lower CK activity observed in the GTE supplemented group Panza et al.

CK activity determined from the circulating blood can be variable, and it is important to ensure the absence of other lesions that could influence CK activity. We found no changes in C-reactive protein and therefore attribute the changes in CK activity to the stress imposed by the exercise protocols Pritchett, Green tea extract supplementation resulted in stable lipid peroxidation, which was used as a marker of oxidative stress.

It is known that oxidative stress is not cumulative along different days of exercise Shing et al. This result is in agreement with a previous study addressing sprints tasks that resulted in an oxidative stress condition in placebo but not in the GTE supplemented group Jowko et al.

The exercise configuration used here leaded to an imbalance in the oxidative status resulting in oxidative stress Vollaard et al. Oxidative stress has important implications on the contraction mechanisms and force output capacity Prochniewicz et al. GTE catechins work as scavengers of reactive species of oxygen better than observed in response to other supplementation strategies commonly used in sports, such as vitamin C and E Zaveri, It supports our idea that the antioxidant properties of GTE are the main explanation to our results in the fatigue condition.

The metabolic damage in the muscle tissue impaired muscle activation in a way visible considering simple markers of surface electromyography. Placebo group showed lower magnitudes of neuromuscular activity and higher indicators of muscle fatigue.

The decrease in the magnitude of neuromuscular activation and its correlation with increase in markers of muscle fatigue is expected in muscles exposed to repeated bouts of exercise under cumulative fatigue Mendez-Villanueva et al. Our cycling trials involved constant workload relative to the individual PPO.

While this rationale seems evident to the placebo group, GTE group showed better indicators of neuromuscular performance and cardiovascular demand.

Our study has limitations. We were unable to fully control the diet of the participants and it may have influenced the higher variability observed in the results, which is also a common issue in previous studies.

To minimize this effect we delivered detailed recommendations to the participants, like avoiding intermittent fasting that affect oxidative stress Dannecker et al. We controlled the highest number of factors possible we could to minimize other variables of influence on our results.

Neuromuscular results showed consistent impairments in the left leg, and it may have some relation with variables of motor control like leg preference, which deserves attention in future researches. Measurements of force would help to determine the extend of damage due to the exercise McHugh et al.

We were unable to evaluate knee extensors force. The pharmacokinetics of the catechins in the blood may have influenced our results. In rats dosed with green tea catechins, concentrations in the blood exhibited peak up to 3 h after intake Janle et al.

In humans, peak plasma concentrations are reached between 1. We tried to minimize these effects by controlling the period of the day in which tests were performed according to the time when the supplementation was intake. Finally, although the dosage is different among the studies, a higher dosage is not related to better results on muscle soreness, for example Arent et al.

Green tea extract supplementation before an event of cumulative fatigue minimizes muscle damage and oxidative stress in trained athletes. It also shows positive effects on neuromuscular parameters related to muscle activation and muscle fatigue.

Therefore, GTE supplementation can be considered a valid strategy in the context of competitive endurance sport aiming at exercise recovery and performance of athletes.

This study was approved by the ethics committee from Universidade Federal do Pampa and all participants signed a consent term prior to start the participation in this research. ÁM, WdS, MS, and FC designed the study, interpretated the data, and prepared the manuscript.

ÁM, WdS, and MS collected and processed the data. All authors approved the final manuscript. ÁM and MS were supported by CAPES-Brazil student fellowships. A research fellow of CNPq-Brazil supports FC. The authors declare that they have no financial or other interest concerning the content of this paper.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The authors would like to thank Caetano Lazzari, Daiana Ávila, and Pamela Mello-Carpes for their technical support during data analysis.

ÁM received a student fellowship from CAPES — Brazil. CNPq — Brazil supported MS and FC. Abbiss, C. Models to explain fatigue during prolonged endurance cycling. Sports Med. doi: PubMed Abstract CrossRef Full Text Google Scholar. Ahtiainen, J. Acute hormonal and neuromuscular responses and recovery to forced vs.

Maximum repetitions multiple resistance exercises. Arent, S. The effects of theaflavin-enriched black tea extract on muscle soreness, oxidative stress, inflammation, and endocrine responses to acute anaerobic interval training: a randomized, double-blind, crossover study.

Sports Nutr. The Kao lab "recently demonstrated that the long-term consumption of tea catechins was beneficial in counteracting the obesity-inducing effects of a high-fat diet, and that their effects may be attributed, at least in part, to the activation of hepatic lipid catabolism" in mice.

We also analyzed changes in energy metabolism, especially lipid metabolism. We demonstrated that GTE intake improved endurance capacity and this was accompanied by an increase in lipid catabolism. Our results support the hypothesis that stimulation of lipid metabolism is a promising strategy for improving the capacity for endurance training.

The ideas for the experiment come from the fact that "skeletal muscles utilize carbohydrates, lipids and amino acids as energy sources, but the ratio in which they are used varies with the intensity of exercise and the level of fitness" as well as the type of exercise involved.

For instance "during endurance exercise, excess glucose is undesirable because it induces insulin secretion, which in turn simultaneously inhibits lipid metabolism and stimulates lactate production.

Conversely, enhanced availability and utilization of free fatty acids are considered to reduce carbohydrate utilization, which in turn spare glycogen and suppresses lactate production and results in an increase in endurance.

To test what effects GTE and its components would have on endurance exercise, the researchers ran two experiments. In the first, swimming endurance capacity was measured at eight weeks of age and the mice were divided into four groups of 10 each. All subjects had unlimited access to water for exercise.

For 10 weeks, controls ate a standardized diet only, while experimental animals had this diet supplemented with 0. During this period experimental mice were exercised in a pool twice a week, but non-exercise mice weren't.

The second experiment was similar to the first but the experimental groups received a diet containing 0. At the beginning of the experiment, the mice swam about 26 minutes until they were exhausted. After 10 weeks on the training regimen, the time-to-exhaustion for the exercise-control mice no GTE or EGCG supplement rose to about 33 minutes, showing the effects of unaided practice on endurance capacity.

From the first week of the experiment, the mice on GTE showed greater improvement compared with the exercise-controls. By week eight, the improved performance of mice on 0. In the global search for enhanced athletic performance and health and fitness , the Kao team said they "have shown that GTE improved endurance capacity and that the improvement was dose-dependent.

A similar effect was observed in mice fed EGCG, a major constituent of GTE, suggesting that the effects of GTE were mediated at least in part by EGCG. Although long-term intake of GTE enhanced endurance capacity, no marked effects were observed after a single dose of GTE, suggesting that some biochemical changes induced by habitual GTE intake, such as up-regulation of muscular beta-oxidation, contributed to the improvement in endurance capacity.

The study found that plasma NEFA non-esterified fatty acid measured immediately after exercise slightly, but significantly, increased in mice fed tea catechins. Though they concede that the effect of plasma fatty acid level on endurance capacity is controversial, they say that increased supply of circulating fatty acids would "induce the uptake of fatty acids, and thereby stimulate lipid metabolism in muscle.

Indeed, lab results showed that muscular beta-oxidation was higher in GTE-fed mice compared with non-exercise and exercise-control mice , "suggesting that GTE enhanced the capacity of muscle to catabolize lipids and utilize fatty acids as an energy source. Taken together the experimental results "suggest that habitual exercise and the intake of GTE enhance fatty acid availability, catabolism and utilization in muscle, and this is accompanied by a reduction in carbohydrate use, which together result in prolonged swimming times to exhaustion.

Kao researchers controlled for possible influences of caffeine and possible weight-fat changes that might affect buoyancy. Aware that previous studies were criticized by the possible role of caffeine on fatty acids and exercise, the Kao researchers reduced the amount of caffeine in supplements.

Thus our results overall suggest that the effects observed in this study are not attributable to caffeine. In particular, our findings that purified EGCG improved endurance capacity supports this conclusion.

The "precise molecular mechanism by which GTE stimulates fatty acid metabolism is unclear at present and remains to be elucidated. For instance, the researchers wrote, "it is possible that the anti-oxidant properties of tea catechins mediate their effects on endurance capacity.

And finally they noted: "Although the clinical efficacy of GTE has not yet been confirmed in human studies, our results suggest that GTE may be a useful tool for improving endurance capacity.

The study, "Green tea extract improves endurance capacity and increases muscle lipid oxidation in mice," was conducted by Takatoshi Murase, Satoshi Haramizu, Akira Shimotoyodome, Azumi Nagasawa and Ichiro Tokimitsu, appears in the online edition of the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, published by the American Physiological Society.

All researchers work at the Biological Science Laboratories of Kao Corp. The American Physiological Society was founded in to foster basic and applied bioscience.

The Bethesda, Maryland-based society has more than 10, members and publishes 14 peer-reviewed journals containing almost 4, articles annually. APS provides a wide range of research, educational and career support and programming to further the contributions of physiology to understanding the mechanisms of diseased and healthy states.

In May, APS received the Presidential Award for Excellence in Science, Mathematics and Engineering Mentoring PAESMEM. Materials provided by American Physiology Society. Note: Content may be edited for style and length. Science News. Facebook Twitter Pinterest LinkedIN Email.

FULL STORY. Results came from the equivalent of about 4 cups of tea a day Although it's difficult to extrapolate from mice eating GTE as a food supplement to a major leaguer or Olympic swimmer sipping green tea, the study's lead author, Takatoshi Murase said: "We estimate that an athlete weighing 75 kilograms pounds would have to drink about four cups 0.

RELATED TERMS Health benefits of tea Tea White tea Physical exercise Green tea Caffeine Herbal tea Weight training.

Green tea extract Green tea extract and sports performance antioxidant protection Greeen Gut health benefits and tissues under performannce stress of exercise. It stimulates thermogenesis, the generation of body heat from digestion, absorption, and metabolism Sports nutrition food. Green tea improves insulin spofts, and stabilizes blood GGreen levels, Green to increased stamina and faster recovery. The ability of green tea extract to stimulate fat utilization and athletic capacity is the focus of a great deal of research from sports physiologists. Green tea extract is produced from the lightly steamed and dried leaves of Camellia sinensiswhich is one of the most widely consumed beverages in the world. Green tea is extremely high in polyphenols which have impressive medicinal actions. Steaming tea inactivates enzymes in tea leaves that would otherwise degrade and oxidize the medicinal polyphenols.


I Researched EVERY Ingredient: BAD News for Athletes - Athletic Greens - Cycling Science Explained Although research suggests that antioxidant supplementation can protect against exercise-induced muscle damage Topical antifungal remedies for athletes foot oxidative Immunity boosting solutions, also extrat Green tea extract and sports performance muscle perormance and hindered adaptation to training were reported Green tea extract and sports performance the Nootropic for Productivity Boost athletes. Geeen purpose of the study was to evaluate performancw effects of green tea extract GTE supplementation on selected blood markers of oxidative stress and muscle damage in sprinters during preparatory phase of their training cycle. Sixteen sprinters participated in a double-blind, randomized, placebo PL -controlled crossover study, including two 4-week treatment periods with PL and GTE mg polyphenols daily. The sprinters performed two repeated cycle sprint tests RST; 4 × 15 s, with 1-min rest intervalsafter PL and GTE supplementation. Blood was sampled before at rest5 min after RST, and after the h recovery. Green tea extract and sports performance

Author: Brasida

5 thoughts on “Green tea extract and sports performance

Leave a comment

Yours email will be published. Important fields a marked *

Design by