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Jae-Keun Oh, Young-Oh Shin, Jin-Ho Yoon, Seong Ho Kim, Hyeon-Cheol Shin and Hye Jeong Hwang

Ecklonia cava polyphenol (ECP) is a potent antioxidant and procirculatory agent that may contribute to improvement of endurance performance during highly intense exercise. This study evaluated the acute effect of an ECP-supplemented drink against a placebo on maximum endurance capacity and related physiological parameters. Twenty men 18–23 yr old volunteered as participants. Each performed 2 randomized trials with a 1-week interval between them. One trial was with ECP and the other with a placebo drink. Participants in this randomized, placebo-controlled, crossover design ingested either a placebo or ECP drink 30 min before each exercise trial. Time to exhaustion, VO2max, and postexercise blood glucose and lactate levels were evaluated. ECP supplementation increased time to exhaustion (2.39 min) compared with placebo. This result was accompanied by a 6.5% higher mean VO2max in the ECP group, although the difference was not statistically significant. The blood glucose level in the ECP group at 3 min after exhaustive exercise was significantly higher than that of the placebo group (+ 9.9%). The postexercise blood lactate levels in the ECP group showed a decreasing trend compared with placebo, but it was nonsignificant. This study was not able to determine any physiological mechanisms behind the improved endurance performance, but, based on these results, it is speculated that the ECP supplementation may have contributed to enhanced oxidation of glucose and less production of lactate during intense exercise, possibly by its free-radical-scavenging and procirculatory activities. However, careful verification is required to elucidate the correct mechanism.

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Ahmed Ismaeel, Michael Holmes, Evlampia Papoutsi, Lynn Panton and Panagiotis Koutakis

any attenuations in strength increases following a RT protocol. Effects on Antioxidant Status and Oxidative Stress The theoretical basis for the use of antioxidant supplements with RT to quench oxygen-free radicals is quite strong. According to the ischemia reperfusion injury theory, muscle

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André L. Estrela, Aline Zaparte, Jeferson D. da Silva, José Cláudio Moreira, James E. Turner and Moisés E. Bauer

. , Bertoni-Freddari , C. , Collins , A. , … Astley , S.B. ( 2002 ). Biomarkers . Molecular Aspects of Medicine, 23 ( 1–3 ), 101 – 208 . PubMed 10.1016/S0098-2997(02)00017-1 Gutteridge , J.M. , & Halliwell , B. ( 2000 ). Free radicals and antioxidants in the year 2000. A historical look to the

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Sang-Ho Lee, Steven D. Scott, Elizabeth J. Pekas, Jeong-Gi Lee and Song-Young Park

can ultimately result in damage to the cells. 5 This is concerning, as an impairment in lipid metabolism and an increase in free radical production can lead to greater risks of cardiovascular and metabolic disease in these athletes. 6 , 7 Octacosanol, a straight-chain, high-molecular-weight, primary

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Nathan A. Lewis, Ann Redgrave, Mark Homer, Richard Burden, Wendy Martinson, Brian Moore and Charles R. Pedlar

carotenoids No range a 1.24 5.93 3.30 378 166 a Abbreviations: CDV, critical difference value; FORD, free-radical oxygen defense; FORT, free-radical oxygen test; GSH, glutathione; post, postintervention; RBC, red blood cell; SOD, superoxide dismutase. a Unknown/not published. The following factors may have

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David C. Nieman, Giuseppe Valacchi, Laurel M. Wentz, Francesca Ferrara, Alessandra Pecorelli, Brittany Woodby, Camila A. Sakaguchi and Andrew Simonson

muscle tissue ( Bloomer et al., 2007 ). The 4-HNE is one of the most abundant and cytotoxic aldehydes generated during free radical-mediated peroxidation of omega-6 polyunsaturated fatty acids in the cell membrane lipid bilayer ( Castro et al., 2017 ; Di Domenico et al., 2017 ; Valacchi et al., 2017

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Jason P. Brandenburg and Luisa V. Giles

The elevated metabolic demands of exercise increase production of free radicals that include reactive oxygen species ( Ferreira & Reid, 2008 ). With the metabolic demands accompanying prolonged and/or high-intensity exercise, the production of free radicals exceeds the endogenous antioxidant

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Tom Clifford

, 1990 ). These findings provide support for the “free radical theory of aging,” which suggests that the age-related increased generation of RS progressively damages cellular structures and curtails the life span ( Cui et al., 2012 ). From a muscle damage context, it has been suggested that the cells

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Graeme L. Close, Craig Sale, Keith Baar and Stephane Bermon

. Owens et al. ( 2015 , 2018 ) Vitamins C and E It has been claimed that increased free radical production increases the magnitude of muscle damage following exercise and, therefore, supplements with vitamins C and E could increase recovery time. Literature, however, indicates that vitamins C and E have

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Michal Botek, Jakub Krejčí, Andrew J. McKune and Barbora Sládečková

with mitochondrial dysfunction and cellular damage 2 that may contribute to fatigue and delayed recovery in athletes. 3 Molecular hydrogen (H 2 ) has been shown to be a strong and selective antioxidant with high scavenger affinity toward cytotoxic hydroxyl free radicals, thus aiding in maintaining