Vitamin D in Healthy Adults After Strenuous Endurance Exercise

Effects of Vitamin D Supplementation on Biochemical Responses and Aerobic Capacity After Strenuous Endurance Exercise

The purpose of this study was to investigate the effects of vitamin D supplementation on biochemical response and aerobic capacity after strenuous endurance exercise (SEE).

All participants conducted a graded exercise test on an ergometric bicycle to determine the maximal oxygen consumption (VO2max) before and after supplementation, and the speed equivalent to 65% VO2max was conducted for a SEE test by ergometric bicycle for 2 hours, followed by increasing 100 RPM until exhaustion. Venous blood samples were drawn before, immediately after, 2-hour after, 4-hour after, 8-hour after, and 24-hour after the SEE test to determine the concentrations of biomarkers. Data was analyzed by Two-way mixed design ANOVA.

Inclusion Criteria:

• The volunteers included have conditions as stated below :

  1. no history of cardiovascular, liver, kidney and diabetes disease
  2. no acute sport injury
  3. male adult whose concentration of 25(OH)D is under 30 ng/mL, and maximal oxygen consumption is over 40 ml/kg/min
  4. did not participated in any clinical trials or research in the last 3 months before our experiment
  5. no supplements were taken during the experimental period
  6. were requested to maintain their regular daily life style and avoid alcohol intake

Exclusion Criteria:

• The volunteers were excluded if they have the situation stated below:

  1. history of cardiovascular, liver, kidney and diabetes disease
  2. acute sport injury
  3. their concentration of 25(OH)D is over 30 ng/mL, or maximal oxygen consumption is under 40 ml/kg/min
  4. participated in any clinical trials or experimental research in the last 3 months before our experiment
  5. taking supplement during the experimental period
  6. did not maintain their regular eating habit or drink alcohol