Search Results

You are looking at 1 - 6 of 6 items for :

  • "beta-carotene" x
Clear All
Restricted access

Antoni Aguiló, Pere Tauler, Emilia Fuentespina, Gerardo Villa, Alfredo Córdova, Josep A. Tur and Antoni Pons

Objective:

The aim of this work was to check the effects of antioxidant supplementation (vitamins E and C, and β-carotene) on the basal iron status of athletes prior to and following their training and competition season (3 months).

Design:

Eighteen amateur trained male athletes were randomly distributed in 2 groups: placebo (lactose) and antioxidant supplemented (vitamin E, 500 mg/d; vitamin C, 1 g/d; and β-carotene, 30 mg/d). The study was double blind. Hematological parameters, dietary intake, physical activity intensity, antioxidant status (GSH/GSSG ratio), and basal iron status (serum iron, transferrin, ferritin, and iron saturation index) were determined before and after the intervention trials.

Results:

Exercise decreased antioxidant defenses in the placebo group but not in the antioxidant-supplemented group. No changes were found in the number of erythrocytes, hematocrit, or hemoglobin concentration, or in values of serum iron parameters, after taking the antioxidant cocktail for 3 months, in spite of the exercise completed. The placebo group showed a high oxidative stress index, and decreases in serum iron (24%) and iron saturation index (28%), which can neither be attributed to aspects of the athletes’ usual diet, nor to hemoconcentration.

Conclusions:

Antioxidant supplementation prevents the decrease of serum iron and the iron saturation index, and a link between iron metabolism and oxidative stress may also be suggested.

Restricted access

Mitchell M. Kanter

Free radicals have been implicated in the development of diverse diseases such as cancer, diabetes, and cataracts, and recent epidemic-logical data suggest an inverse relationship between antioxidant intake and cardiovascular disease risk. Data also suggest that antioxidants may delay aging, Research has indicated that free radical production and subsequent lipid peroxidation are normal sequelae to the rise in oxygen consumption with exercise. Consequently, antioxidant supplementation may detoxify the peroxides produced during exercise and diminish muscle damage and soreness. Vitamin E, beta carotene, and vitamin C have shown promise as protective antioxidants. Other ingestible products with antioxidant properties include selenium and coenzyme Q10. The role (if any) that free radicals play in the development of exercise-induced tissue damage, or the protective role that antioxidants may play, remains to be elucidated. Current methods used to assess exercise-induced lipid peroxidation are not extremely specific or sensitive; research that utilizes more sophisticated methodologies should help to answer many questions regarding dietary antioxidants.

Restricted access

Christian Mariacher, Hannes Gatterer, Joachim Greilberger, Radoslav Djukic, Michaela Greilberger, Marc Philippe and Martin Burtscher

Background/Objectives:

To compare the effects of a 3-week supplementation between two different mixtures of antioxidants and placebo on aerobic exercise performance in acute normobaric hypoxia.

Subjects/Methods:

Seventeen subjects were randomly assigned in a double-blind fashion to receive a broad-based antioxidants supplement containing beta-carotene, ascorbic acid, d-alpha-tocopherol-succinate, N-acetylcysteine, riboflavin, zinc, and selenium (antioxidant capsule group [AO group]), or a combination of alpha-ketoglutaric acid (α-KG) and 5-hydroxymethylfurfural (5-HMF; CYL concentrate supplementation group [CS group]), or placebo (PL group). Before and after supplementation, subjects performed two incremental cycle-exercise tests until exhaustion. The first test was conducted under normoxic conditions (LA, FiO2 of 20.9%, ~547 m) and the second after the 3-week supplementation period under normobaric hypoxic conditions (AHA, FiO2 of 12.9%, ~4300m).

Results:

In CS peak cycling performance (peak power) declined from LA to AHA 7.3% (90% CI: 2.2–12.4) less compared with PL (p = .04) and 6.7% (90%CI: 3.2–10.2) less compared with AO (p = .03). Better maintenance of aerobic exercise capacity in CS was associated with an attenuated reduction in maximal heart rate in hypoxia.

Conclusions:

Aerobic exercise performance was less impaired in acute normobaric hypoxia after 3 weeks with supplementation of α-KG and 5-HMF compared with a broad-based antioxidants supplement or PL.

Restricted access

David C. Nieman, Courtney L. Capps, Christopher R. Capps, Zack L. Shue and Jennifer E. McBride

-Freeman & Sesso, 2014 ). Of all carotenoids studied in vitro, lycopene is the most effective singlet oxygen scavenger and exhibits quenching rates multiple times greater than beta-carotene and vitamin C ( Shi & Le Maguer, 2000 ). Human trials suggest that tomato carotenoid intake reduces systemic inflammation in

Restricted access

Nathan A. Lewis, Andrew J. Simpkin, Sarah Moseley, Gareth Turner, Mark Homer, Ann Redgrave, Charles R. Pedlar and Richard Burden

function (thyroid stimulating hormone); nutritional status (vitamin C, vitamin D, alpha-tocopherol, and the carotenoids: lutein, alpha-carotene, and beta-carotene); muscle damage and inflammation (creatine kinase, C-reactive protein) were measured at the beginning of the study period and again prior to the

Open access

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

.1002/14651858.CD000980.pub4 Hemila , H. , Virtamo , J. , Albanes , D. , & Kaprio , J. ( 2003 ). Physical activity and the common cold in men administered vitamin E and beta-carotene . Medicine & Science in Sports & Exercise, 35 ( 11 ), 1815 – 1820 . PubMed doi:10.1249/01.MSS.0000093616.60899.92 10