Whey protein precludes lipid and protein oxidation and improves body weight gain in resistance-exercised rats.
BACKGROUND
Resistance exercise such as weight-lifting (WL) increases oxidation products in plasma, but less is known regarding the effect of WL on oxidative damage to tissues. Dietary compounds are known to improve antioxidant defences. Whey protein (WP) is a source of protein in a variety of sport supplements and can enhance physical performance.


OBJECTIVE
To evaluate the effect of WL on biomarkers of lipid and protein oxidation, on liver antioxidants and on muscle growth in the absence or presence of WP in rats.


METHODS
Thirty-two male Fisher rats were randomly assigned to sedentary or exercise-trained groups and were fed with control or WP diets. The WL programme consisted of inducing the animals to perform sets of jumps with weights attached to the chest. After 8 weeks, arteriovenous blood samples, abdominal fat, liver and gastrocnemius muscle were collected for analysis.


RESULTS
WP precludes WL-mediated increases in muscle protein carbonyl content and maintains low levels of TBARS in exercised and sedentary animals. WL reduced liver CAT activity, whereas WP increased hepatic glutathione content. In addition, WL plus WP generated higher body and muscle weight than exercise without WP.


CONCLUSIONS
These data suggest that WP improves antioxidant defences, which contribute to the reduction of lipid and protein oxidation as well as body and muscle weight gain in resistance-exercised rats.
Research in Biological Sciences-NUPEB, Ouro Preto University, Minas Gerais, Brazil. fabianokenji@gmail.com
Fabiano Kenji
FK
Haraguchi
Marcelo Eustáquio
ME
Silva
Leandro Xavier
LX
Neves
Rinaldo Cardoso
RC
dos Santos
Maria Lúcia
ML
Pedrosa
D050153:Abdominal Fat / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D015415:Biomarkers / Q000032:analysis; D001835:Body Weight / Q000187:drug effects*; D002374:Catalase / Q000378:metabolism; D004032:Diet; D005978:Glutathione / Q000032:analysis; D006003:Glycogen / Q000032:analysis; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D008894:Milk Proteins / Q000494:pharmacology*; D018482:Muscle, Skeletal / Q000737:chemistry; D010084:Oxidation-Reduction; D010805:Physical Conditioning, Animal; D051381:Rats; D055070:Resistance Training; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D015430:Weight Gain / Q000187:drug effects; D000067816:Whey Proteins
D000975:Antioxidants; D015415:Biomarkers; D008894:Milk Proteins; D017392:Thiobarbituric Acid Reactive Substances; D000067816:Whey Proteins; D006003:Glycogen; D002374:Catalase; D005978:Glutathione