The purpose of this investigation is to test the hypothesis that chronic supplementation with a dairy-based beverage containing a mixture of blueberry, green tea, and cocoa flavonoids (non-nutritive natural plant compounds) will ameliorate exercise-related changes in gut permeability and inflammation. In a previous feeding study in humans, (NCT02728570) a high flavonoid diet (flavonoids at 340 mg/1000kcal) was effective in mitigating gut permeability and inflammation in overweight and obese adults compared to a low flavonoid diet (10mg/1000 kcal). To test this hypothesis, 20 trained cyclists will complete a randomized crossover study with supplementation for 2 weeks with a dairy-based sports beverage containing either a high flavonoid (approximately 620 mg) or low flavonoid (approximately 5mg) beverage. After the two week intervention, cyclists will complete a 1 hour cycling trial (45 min at 65% VO2 max then 15 minute time trial). The primary endpoints will be gut permeability as measured by plasma intestinal fatty acid binding protein (I-FABP) and the differential sugar test. Secondary endpoints will include gut inflammation (measured via fecal calprotectin), plasma cytokines (IL-6, IL-10 and TNFα) and plasma LPS. In addition, the distance completed in the time trial is a secondary endpoint.

Inclusion Criteria:

• Male or female of any race or ethnicity between 18 to 49 years of age
• Competed in a road race or triathlon in past 12 months
• Free of chronic disease and GI conditions
• Train at least 3 times per week, 1 hour at a time on average
• Willing to prepare and consume provided pre-workout beverage daily
• Maintain weight (no more/less than 5 kg change)
• Willing to avoid consumption of high flavonoid foods/supplements, large dose vitamin and mineral supplements, and NSAIDs or other medications known to affect inflammation during study period
• Willing to provide urine, stool, and blood samples

Exclusion Criteria:

• Age <18 or >50 years
• Medical history of heart disease, hypertension, diabetes, Crohn's disease, IBS, colitis, celiac disease, inflammatory or autoimmune disease, and lactose intolerance
• Uncontrolled hypertension: diastolic blood pressure >95 mm Hg or systolic blood pressure >160 mm Hg
• For women: pregnancy, breast feeding or postpartum <6 months
• Food allergies or restrictions to treatment/placebo beverages
• Chronic use of NSAIDs
• Consumption of flavonoid supplements <1 month prior to study start
• Antibiotic use <3 months prior to study start
• Other conditions (medical, psychiatric, or behavioral) that may present a safety hazard to the participant or interfere with study participation, as determined by the principal investigators