title: Beneficial effects of gradual intense exercise in tissues of rats fed with a diet deficient in vitamins and minerals: a pilot study.
abstract: OBJECTIVE
  This study evaluated the preliminary effects of intense physical training (swimming) on oxidative stress in rats with nutritional deficiencies.
  
  
  METHODS
  Rats were fed with a standard diet or a diet deficient in vitamins and minerals for 4 months. The deficient diet contained one-fourth of the recommended vitamin and mineral levels for rats. From the second month, half of the animals were subjected to a swimming exercise in a plastic container with water maintained at 34 +/- 1 degrees C for 1 h/d, five times per week, for 11 wk. The rats were subjected to swimming exercise with loads attached to the dorsal region, which were progressively increased according to their body weight (1% to 7%). Sedentary rats were transported to the experimental room and handled as often in a similar way as the exercise group, except that they were not put in water.
  
  
  RESULTS
  In the exercised group, blood lactate levels were significantly lower and the heart weight/body weight ratio was significantly higher than in the sedentary group (P < 0.05). Increased lipid peroxidation was observed in the liver, heart, and skeletal muscle of rats fed with the deficient diet, but it was completely reversed by exercise. Exercise also decreased lipid peroxidation levels in the heart and skeletal muscle of rats fed with the standard diet (P < 0.05).
  
  
  CONCLUSIONS
  This pilot study leads to the continuity of the studies, because the partial results observed suggest that inadequate nutrition may enhance oxidative stress, and that intense chronic physical training may activate antioxidant defenses, possibly by hormesis.
authors.affiliation: Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil.
authors.forename: Angélica
authors.initials: A
authors.lastname: Teixeira
authors.forename: Liz
authors.initials: L
authors.lastname: Müller
authors.forename: Alessandra A
authors.initials: AA
authors.lastname: dos Santos
authors.forename: Patrícia
authors.initials: P
authors.lastname: Reckziegel
authors.forename: Tatiana
authors.initials: T
authors.lastname: Emanuelli
authors.forename: João Batista T
authors.initials: JB
authors.lastname: Rocha
authors.forename: Marilise E
authors.initials: ME
authors.lastname: Bürger
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001361:Avitaminosis / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D003677:Deficiency Diseases / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D006321:Heart / Q000033:anatomy & histology*; D019344:Lactic Acid / Q000097:blood; D015227:Lipid Peroxidation; D008099:Liver / Q000033:anatomy & histology / Q000378:metabolism; D008297:Male; D008903:Minerals / Q000008:administration & dosage; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D009929:Organ Size; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010805:Physical Conditioning, Animal / Q000502:physiology*; D010865:Pilot Projects; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013550:Swimming; D017392:Thiobarbituric Acid Reactive Substances; D014815:Vitamins / Q000008:administration & dosage
chemical_list: D000975:Antioxidants; D008903:Minerals; D017392:Thiobarbituric Acid Reactive Substances; D014815:Vitamins; D019344:Lactic Acid