Exercise Recovery and Endurance Clinical Trial
Official title:
Establishing the Effect of Long-term Orange Peel Extract Supplementation on Exercise Performance and Recovery
Rationale: Numerous studies have shown the positive effect of a healthy diet and regular
moderate exercise. Although, exercise has also been correlated with an increase in reactive
oxygen species (ROS) production and a higher incidence of injury. ROS production seems to
induce muscle damage, which reduces muscle performance and induces fatigue. Increasing
muscle recovery could be an effective way to increase exercise performance. Several food
ingredients have been of growing interest due to their specific functioning on the human
body. Citrus flavonoids are abundantly available in citrus fruits. Prior studies show a
positive effect of citrus flavonoids on endothelial function, by promoting vasodilation. In
addition it has a positive effect on the nitric oxide (NO) synthesis, a known compound in
regulating endothelial response. This capacity of citrus flavonoids could be useful in
stimulating performance and recovery after exercise. Additionally, the ability of scavenging
ROS could reduce muscle damage caused by exercise induced oxidative damage.
Objective: Determine the 4-week effect of daily citrus flavonoid supplementation on exercise
recovery and performance.
Study design: Randomized, double-blind, placebo-controlled study with parallel design, in
which 40 subjects engage in three exercise sessions. The sessions will be subdivided into a
pre-test and test 1 and 2. Between test 1 and 2, participants receive daily for 4 weeks
citrus flavonoid supplement or a placebo. Each day, subjects should consume 2 capsules each
morning, containing in total 500 mg of citrus flavonoids or 500 mg placebo.
Study population: The subjects will be healthy normal weight trained males, with an age of
18 - 25. Additionally, subjects are non-smokers and free of a medication.
Intervention: Participants will be randomly placed in either the citrus flavonoid or placebo
group. Participants will be instructed to ingest 2 capsules each morning for 4 consecutive
weeks. Each capsule equals to 250 mg of citrus flavonoids or cellulose in case of the
placebo treatment.
Main study parameters/endpoints: The main study parameter is the average amount of work load
produced during the 10-minute time trail test. In addition, oxygen per minute will be
determined as well as the heart rate. Finally, for each test, the subjective rating of
perceived exertion (RPE) will be determined during the pre-test and test 1 and 2 by using a
Borg scale.
n/a
Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator)