Racial differences in postprandial oxidative stress with and without acute exercise.
High-kilocalorie feedings induce oxidative stress. Acute exercise has the potential to attenuate postprandial oxidative stress. No study has determined whether there are racial differences in postprandial oxidative stress with and without a preceding bout of acute exercise.


OBJECTIVE
To investigate the impact of acute exercise on blood oxidative-stress biomarkers, triglycerides (TAG), and glucose in African American (AA) and White (W) women.


METHODS
10 AA (age 29 +/- 3 yr, body-mass index [BMI] 31 +/- 3 kg/m(2)) and 10 W (age 30 +/- 2 yr, BMI 30 +/- 3 kg/m(2)) women consumed a meal of 1.2 g of fat and carbohydrate and 0.25 g of protein per kilogram body mass, on 2 occasions-with and without a session of aerobic exercise 15 min preceding the meal (45 min cycling at 65% heart-rate reserve)--in a random-order crossover design. Blood samples were collected premeal (fasted), and at 1, 2, 4, and 6 hr postmeal and assayed for TAG, glucose, xanthine oxidase activity, hydrogen peroxide (H2O2), and malondialdehyde (MDA). Area under the curve (AUC) was calculated for each variable.


RESULTS
AUC was lower for AA compared with W for both the exercise and the no exercise conditions for H2O2, MDA, and TAG (p < .01). However, acute exercise had no effect on decreasing the AUC for any variable in either AA or W women (p > .05).


CONCLUSIONS
Postprandial lipemia and oxidative stress are lower in AA than in W overweight/obese women. However, acute exercise, performed at the intensity and duration in the current study, does not influence postprandial lipemia or oxidative stress in AA or W women.
Bloomer
Richard J
RJ
Cardiorespiratory/Metabolic Laboratory, University of Memphis, Memphis, TN 38152, USA.
Cole
Bradford
B
Fisher-Wellman
Kelsey H
KH
D000328:Adult; D001741:Black or African American; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D018592:Cross-Over Studies; D004041:Dietary Fats / Q000008:administration & dosage / Q000378:metabolism; D015444:Exercise / Q000502:physiology*; D005215:Fasting / Q000502:physiology; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation; D009765:Obesity / Q000097:blood / Q000378:metabolism; D050177:Overweight / Q000097:blood / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology*; D019518:Postprandial Period / Q000502:physiology*; D014280:Triglycerides / Q000097:blood; D044465:White People
D015415:Biomarkers; D001786:Blood Glucose; D004041:Dietary Fats; D014280:Triglycerides