The polyphenol composition of green tea leaves is characterized by the flavonoid catechins, that is, catechin gallate, epicatechin gallate, epigallocatechin gallate (EGCG), epicatechin epigallate, gallocatechin, and gallocatechin gallate ( Xu et al., 2004 ). Because of the processing methods of the
Mark Elisabeth Theodorus Willems, Mehmet Akif Şahin and Matthew David Cook
Ewa Jówko, Jaroslaw Sacharuk, Bozena Balasinska, Jacek Wilczak, Malgorzata Charmas, Piotr Ostaszewski and Robert Charmas
To evaluate the effect of acute ingestion of green tea polyphenols (GTP) on blood markers of oxidative stress and muscle damage in soccer players exposed to intense exercise.
This randomized, double-blinded study was conducted on 16 players during a general preparation period, when all athletes participated in a strength-training program focused on the development of strength endurance. After ingestion of a single dose of GTP (640 mg) or placebo, all athletes performed an intense muscle-endurance test consisting of 3 sets of 2 strength exercises (bench press, back squat) performed to exhaustion, with a load at 60% 1-repetition maximum and 1-min rests between sets. Blood samples were collected preexercise, 5 min after the muscle-endurance test, and after 24 hr of recovery. Blood plasma was analyzed for the concentrations of thiobarbituric acid–reacting substances (TBARS), uric acid (UA), total catechins, total antioxidant status (TAS), and activity of creatine kinase (CK); at the same time, erythrocytes were assayed for the activity of superoxide dismutase (SOD).
In both groups, plasma TBARS, UA, and TAS increased significantly postexercise and remained elevated after a 24-hr recovery period. SOD activity in erythrocytes did not change significantly in response to the muscle-endurance test, whereas in both groups plasma CK activity increased significantly after 24 hr of recovery. Acute intake of GTP cased a slight but significant increase in total plasma catechins. However, GTP was found not to exert a significant effect on measured parameters.
Acute ingestion of GTP (640 mg) does not attenuate exercise-induced oxidative stress and muscle damage.
Patrick J. O’Connor, Amanda L. Caravalho, Eric C. Freese and Kirk J. Cureton
Compounds found in the skins of grapes, including catechins, quercetin, and resveratrol, have been added to the diet of rodents and improved run time to exhaustion, fitness, and skeletal-muscle mitochondrial function. It is unknown if such effects occur in humans. The purpose of this experiment was to investigate whether 6 wk of daily grape consumption influenced maximal oxygen uptake (VO2max), work capacity, mood, perceived health status, inflammation, pain, and arm-function responses to a mild eccentric-exercise-induced arm-muscle injury. Forty recreationally active young adults were randomly assigned to consume a grape or placebo drink for 45 consecutive days. Before and after 42 d of supplementation, assessments were made of treadmill-running VO2max, work capacity (treadmill performance time), mood (Profile of Mood States), and perceived health status (SF-36 Health Survey). The day after posttreatment treadmill tests were completed, 18 high-intensity eccentric actions of the nondominant elbow flexors were performed. Arm-muscle inflammation, pain, and function (isometric strength and range of motion) were measured before and on 2 consecutive days after the eccentric exercise. Mixed-model ANOVA showed no significant effect of grape consumption on any of the outcomes. Six weeks of supplemental grape consumption by recreationally active young adults has no effect on VO2max, work capacity, mood, perceived health status, inflammation, pain, or physical-function responses to a mild injury induced by eccentric exercise.
Farnoosh Mafi, Soheil Biglari, Alireza Ghardashi Afousi and Abbas Ali Gaeini
.cger.2017.02.003 Yu , P.L. , Pu , H.F. , Chen , S.Y. , Wang , S.W. , & Wang , P.S. ( 2010 ). Effects of catechin, epicatechin and epigallocatechin gallate on testosterone production in rat leydig cells . Journal of Cellular Biochemistry, 110 ( 2 ), 333 – 342 . PubMed ID: 20432242 doi:10
Romain Meeusen and Lieselot Decroix
), which are found in onions, leeks, and broccoli; flavanols (e.g., –catechin, [–]-epicatechin, epigallocatechin, and epigallocatechin gallate), which are abundant in green tea, red wine, and chocolate; and anthocyanidins (e.g., pelargonidin, cyanidin, and malvidin), whose sources include red wine and
Ronald J. Maughan, Louise M. Burke, Jiri Dvorak, D. Enette Larson-Meyer, Peter Peeling, Stuart M. Phillips, Eric S. Rawson, Neil P. Walsh, Ina Garthe, Hans Geyer, Romain Meeusen, Luc van Loon, Susan M. Shirreffs, Lawrence L. Spriet, Mark Stuart, Alan Vernec, Kevin Currell, Vidya M. Ali, Richard G.M. Budgett, Arne Ljungqvist, Margo Mountjoy, Yannis Pitsiladis, Torbjørn Soligard, Uğur Erdener and Lars Engebretsen
promote lean mass retention ( Krieger et al., 2006 ; Wycherley et al., 2012 ) Pyruvate No data Small-to-trivial effect ( Onakpoya et al., 2014a ) Chromium Potentiates biological actions of insulin No effect ( Tian et al., 2013 ) Green tea (polyphenol catechins and caffeine) Thermogenic agent and