Cocoa Intake for Health Promotion in Athletes
Condition: Healthy Subjects
Study type: Interventional

Summary: 
      Athletes consume an extra of nutritional supplements every day with the purpose of improving
      their athletic performance, sometimes without being aware of their health. Cocoa could be a
      good nutritional supplement for athletes without causing them adverse effects. One of the
      most common health concerns in athletes are gastrointestinal problems. The cause of these
      problems seem to be a compendium of physiological and mechanical causes that are altered due
      to nutritional factors. Currently, there is no assay in which a nutritional intervention
      study has been proposed over time of training, in order to improve the gastrointestinal
      problems associated with the performance of physical exercise.
    

Detailed description: 
      The objective of this project is to investigate the benefits of daily consumption of cocoa in
      endurance athletes in:

      A) Gastrointestinal problems associated with exercise. B) Reinforcement of the
      gastrointestinal barrier. C) Parameters of inflammation and oxidative stress. D) Sports
      performance. E) Body composition

      The starting hypothesis of this project is based on the fact that daily cocoa consumption
      could improve the gastrointestinal symptoms associated with resistance exercise. Cocoa
      decreases the symptoms associated with splenic hypovolemia and strengthens the
      gastrointestinal epithelial barrier increasing the presence of Lactobacillus spp. and
      Bifidobacterium spp. in the intestinal microbiota.

      A randomized, blinded, parallel placebo controlled intervention study will be carried out in
      endurance athletes who train in the sports facilities of the European University of Madrid.
      The number of male athletes for the study will be 56 (28 in each experimental group), all of
      them aimed at competition with an age between 18 and 40 years and an aerobic power
      consumption of oxygen greater than or equal to 55 mL / kg / min). The calculation of the
      sample size has been made selecting with a significance level alpha = 0.05 and a power (beta)
      of 0.90 for a 2-tailed analysis, taking into account we want to detect a difference of at
      least 15% in the improvement of the gastrointestinal symptoms, that the standard detected
      deviation in the questionnaire to be used, in previous studies, is 1.5 points out of 9 and
      that the expected proportion of losses is 15%.

      Before and after the intervention, the athletes will do a test in which we will measure their
      maximum aerobic capacity. This will be done in the facilities of Europea University of Madrid
      where there is available a rolling belt. Also, they will do a second test in which we will
      measure the time they spend running a kilometer at the maximum speed. Body composition will
      be evaluated by dual-energy X-ray absorptiometry (DEXA). Blood, urine and feces samples will
      be required before and after the physical tests. Blood and urine samples will be collected in
      the morning while the feces samples will be collected the day before. The biological samples
      will be frozen at -80ºC until analyses.

      The intervention will be carried out for 10 weeks. Cocoa or placebo will be provide in a
      single daily intake of 5 g of cocoa containing 500 mg of flavanols (dose at which a prebiotic
      effect has been demonstrated) or 5 g of maltodextrin.
    

Intervention name(s): Cocoa group; Placebo group
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): Athletes perform the same training program and they take 5 g of cocoa (83 mg of flavonoids per gram of cocoa) mixed with low-fat milk for 10 weeks.; The athletes perform the same training program and they take for 10 weeks 5 g maltodextrin mixed with low-fat milk for 10 weeks
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Double blind placebo controlled study
Masking: Double (Participant, Investigator)
Primary purpose: Prevention
Keywords: Nutritional Supplement; Cocoa; Prebiotic; Physical Exercise; Gut Microbiota