Exercise and Non-exercise Effect Upon Vitamins E and C
Conditions
Keywords
Vitamin E, Vitamin C, Exercise, Antioxidant
Brief summary
Moderate exercise is thought to be one of the best known means to improve how insulin works in people. Taking vitamin C and vitamin E is also thought to have the same effect. This study is being done to see if taking vitamin C and vitamin E improves or hinders how insulin works when people do not exercise and when they do exercise.
Detailed description
The objective of the study is to determine in humans whether anti-oxidant supplementation with ascorbate (vitamin C) or R,R,R-α-tocopherol acetate (vitamin E) improves insulin sensitivity in the untrained state but blocks exercise-induced increases in insulin sensitivity and other adaptations to exercise. The results will provide new information on the roles of anti-oxidant supplementation in modifying insulin sensitivity, and will inform guidelines for anti-oxidant supplementation as an adjunct to exercise.
Interventions
DIETARY_SUPPLEMENTVitamin E and Vitamin C
Vitamin E 400 iu/dose daily times 56 days Vitamin C 500 mg/dose twice daily times 56 days
Sponsors
USDA Grand Forks Human Nutrition Research Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
TRIPLE (Subject, Caregiver, Investigator)
Eligibility
Sex/Gender
ALL
Age
30 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* 30 to 50 years of age * Willing to not change eating habits * Willing to not change physical activity habits * Willing to complete the 28 week study * Able to swallow pills
Exclusion criteria
* smoke or use tobacco or nicotine in any form including snuff, pills, and patches * take any medication that makes you unable to do hard exercise * have cardiovascular, pulmonary, and/or a metabolic disease such as diabetes * have uncontrolled high blood pressure * have alcohol, anabolic steroids, or other substance abuse issues * consume more than 3 alcoholic drinks/week * have any joint or muscle injuries that affects your ability to exercise * have cancer (other than skin cancer or carcinoma in situ of the cervix) * are pregnant or nursing
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| (1) Blood glucose and insulin following glucose challenge in non-exercising and exercising people (BMI 27 to 35) taking anti-oxidants (vitamin E and vitamin C) or placebo. | 28 weeks | Individuals will be in placebo and vitamin supplemented groups in a cross-over design. A total of 6 oral glucose tolerance tests will be performed per subject in the study. |
Secondary
| Measure | Time frame |
|---|---|
| (1) Resting metabolic rate, body composition, plasma oxidative stress, plasma vitamin E and vitamin C levels in non-exercising and exercising people (BMI 27 to 35) taking anti-oxidants (vitamin E and vitamin C) or placebo. | 28 weeks |
| (2) Fitness measures (heart rate, exercise work, VO2, VCO2, blood lactate) in non-exercising and exercising people (BMI 27 to 35) taking anti-oxidants (vitamin E and vitamin C) or placebo. | 28 weeks |
Countries
United States
Outcome results
None listed