The Effects of Vitamin E and Vitamin C and Exercise

Study Overview
=================
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.

Official Title
-----------------
Modulation of Insulin and Exercise Responses by Vitamin E and Vitamin C

Conditions
-----------------
Exercise and Non-exercise Effect Upon Vitamins E and C

Intervention / Treatment
-----------------
* Dietary Supplement: Vitamin E and Vitamin C


Participation Criteria
=================
Eligibility Criteria
-----------------
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

Ages Eligible for Study
-----------------
Minimum Age: 30 Years
Maximum Age: 50 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Vitamin E and Vitamin C<br>4 weeks with Vitamin E and Vitamin C supplementation with no exercise and 4 weeks of supplementation with prescribed exercise. | Dietary Supplement: Vitamin E and Vitamin C<br>* Vitamin E 400 iu/dose daily times 56 days Vitamin C 500 mg/dose twice daily times 56 days<br>|
| No Intervention: Placebo<br>Placebos instead of the Vitamin E and Vitamin C supplements | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| (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. | 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. | 28 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | 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 | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Vitamin E, Vitamin C, Exercise, Antioxidant