Blueberry Supplementation and Inflammation Resolution After Exercise

Participants will be randomized to the blueberry or placebo groups. The parallel group design is being utilized in this study because of the "repeat exercise bout" effect (i.e., post-exercise muscle damage and inflammation are reduced when the same bout is repeated within days and weeks of the first bout). Participants will come to the lab at 7:00 am at the beginning of the 2-week supplementation period, and then Monday (eccentric exercise bout) and Tuesday through Friday (recovery) in an overnight fasted state. Seven blood samples will be collected and analyzed for various measures of muscle damage, oxylipins, and inflammation. After each of the blood draws, participants will provide a muscle soreness rating (DOMS). Three 24 h urine samples will be collected and analyzed for key metabolic markers of blueberry ingestion.

Visit #1 Pre-Study Study participants will come to the performance lab for orientation to study procedures. This will include a review of the consent form, completion of basic questionnaires, and an introduction to the eccentric muscle exercise bout and the strength/power performance testing protocol (about 1.5 hours) (visit #1). During visit #1, participants will be given two 3-day food records with thorough written and oral instructions on recording procedures (with food models). The 3-day food records will be completed on a Thursday, Friday, and Saturday sequence prior to visits #2 and #3. During visit #1, participants will be given three 24 h urine collection bottles with thorough written and oral instruction on collection procedures. The 24 h urine collection bottles will be collected on the day before visits #2, #3, and #7.

This will be followed by another lab session for pre-study measurements and sample collection (visit #2). Participants will be randomized to blueberry or placebo groups, and provided a 2-weeks supply of supplements. Participants in the blueberry and placebo groups will consume 26 g/d powder mixed in water each day in split doses (half in the morning, half in the afternoon). Compliance will be checked weekly through email correspondence from the Research Manager. A 3-day food record will be collected at the beginning and end of the 2-week supplementation period to assess the background diet. The 3-day food record will be turned in and reviewed by the research team, and analyzed for nutrient and flavonoid content using the Food Processor Version 11.1 (ESHA Research, Salem, OR, USA). ESHA's port utility (Version 4.0; ESHA Research, Salem, OR, USA) will be used to upload the Flavonoid Values for USDA Survey Foods and Beverages (FNDDS) 2007-2010 database. Food/beverage intake will be assessed for macro- and micro-nutrients, total flavonoids and subtotals for each of the six flavonoid subclasses, and three individual flavonoid values (quercetin, cyanidin, and epigallocatechin gallate (EGCG)).

The study will include 5 other lab visits during a one-week period starting on a Monday (visit #3), with morning visits at 7:00 am on Tuesday through Friday (visits 4-7). At each of the 7 lab visits, study participants will come to the lab at 7:00 am not having consumed food or beverages (other than water) for at least the previous 9 hours, and having abstained from vigorous exercise for at least the previous 24-48 hours. The Monday session will take about 2.5 hours (7:00 to 9:30 am), and the Tuesday through Friday sessions will take about 30-45 minutes each. The total amount of time participants will be asked to volunteer for this study is about 8-9 hours at the performance lab.

Baseline Testing (Visit #2) Participants will come to the lab at 7:00 am in an overnight fasted state dressed in exercise clothes. Participants will provide a blood sample using standard phlebotomy procedures. Participants will turn in their 24 h urine collection bottle and 3-day food record. Height, body weight, and body composition will be measured in a private section of the lab. Bioelectrical impedance (BIA) using the seca BIA scale will be used to assess body composition (i.e., the percent of body weight that is fat tissue) and body weight. Participants will remove shoes and socks and stand with bare feet on the seca scale for about 7-10 seconds while using the hands to grasp the side rails. Percent body fat will also be measured using the BodPod. Participants will sit inside the BodPod with a tight-fitting swim suit for about 10 minutes while body fat is calculated. Delayed onset of muscle soreness (DOMS) will be assessed using a 1-10 scale.