Blueberries, Bananas, Exercise Recovery
Condition: Inflammatory Response; Metabolic Disturbance; Immune Suppression
Study type: Interventional

Summary: 
      The PURPOSE of this study is to investigate the combined influence of 2-weeks blueberry
      ingestion and banana ingestion (during exercise) on performance and in mitigating metabolic
      perturbation, immune dysfunction, and increase in inflammation following a 75-km cycling time
      trial. We hypothesize that the combination of 2-weeks ingestion of blueberries (versus
      placebo) and acute ingestion of bananas (versus water alone) during 75-km cycling will:

        1. Enhance performance.

        2. Attenuate the magnitude of metabolic perturbation due to exercise (using a targeted
           panel of metabolites) which may be associated with increased plasma levels of beneficial
           gut-derived phenolics.

        3. Attenuate post-exercise inflammation (as measured with cytokines, muscle damage markers,
           regulatory lipid mediators, ex-vivo monocyte cell cultures, and targeted immune proteins
           including S100A8 and S100A12).

        4. Counter post-exercise downturns in innate immune function (natural killer cell lytic
           activity), and viral defense (using an ex-vivo cell culture with Hela cells).
    

Detailed description: 
      LAB VISIT #1: ORIENTATION AND BASELINE TESTING (about 1.5 hours):

      One to two weeks prior to the start of the study, study participants will report to the NCRC
      Human Performance Lab for orientation and baseline testing. Study participants will be
      screened to verify "low risk" status for cardiovascular disease, and provide voluntary
      consent. Demographic and training histories will be acquired with questionnaires. Study
      participants will be tested for VO2max (i.e., maximal oxygen consumption) using the Lodi
      cycle ergometer. Percent body fat will be measured using the BodPod. Study participants will
      sit inside the BodPod with a tight-fitting swim suit for about 10 minutes while body fat is
      calculated.

      LAB VISIT #2: START OF 2-WEEK SUPPLEMENTATION PERIOD (about 20 minutes)

      On the assigned date and time, study participants will return to the lab in an overnight
      fasted state (9 or more hours with no food or beverage including coffee and tea, other than
      water). A blood sample will be collected from an arm or hand vein by trained phlebotomists.
      Each blood sample will not exceed 35 ml (2.3 tablespoons), and will be analyzed for
      indicators of immune function, inflammation, muscle damage, stress hormones, and indicators
      of plant polyphenol metabolism.

      Study participants will be randomized to blueberry and placebo groups, and be given a 14-day
      supply of freeze-dried blueberry powder or placebo powder. The blueberry and placebo
      supplements will be ingested daily for 2-weeks prior to participation in the 75-km cycling
      time trial, the day of the exercise trial (after the blood draw, and supplied at the lab),
      and one day of recovery (after the blood draw, and supplied at the lab (thus 16 days total).
      The blueberry powder supplement (26 g per day or approximately one cup fresh blueberries
      equivalent) will consist of freeze-dried wild blueberries prepared by Future Ceuticals
      (Momence, IL). This product contains all of the polyphenols (in particular, anthocyanins),
      fiber, and natural sugars contained in fresh wild blueberries. The placebo powder will look
      identical but not contain freeze-dried blueberries. The placebo blueberry powder will consist
      of blueberry flavoring (2.8%), coloring (0.7% artificial purple, 0.3% artificial red),
      maltodextrin (21%), fructose (3.5%), citric acid (0.7%), and a silica flow agent (0.5%).
      Study participants will consume the blueberry and placebo powders by mixing them in fruit
      juices, yogurts, milk, or other products during the first meal of each day for two weeks. The
      blueberry and placebo powders should be stored in the freezer section of the refrigerator in
      the containers supplied to study participants.

      LAB VISIT #3: POST-SUPPLEMENTATION LAB VISIT WITH 75-km CYCLING (about 8-9 hours)

        -  During the 3-day period prior to the 75-km cycling trial, study participants will taper
           exercise training and ingest a moderate-carbohydrate diet, with foods chosen from a food
           list moderating use of high fat foods, visible fats, and fruit/vegetable polyphenols.
           Study participants will record all food and beverage intake during the 3-day period.

        -  After the 2-week supplementation period, study participants will return to the lab at
           7:00 am in an overnight fasted and rested state (on the same day of the week and time as
           the pre-supplementation lab visit).

             -  Study participants will turn in the 3-day food record.

             -  Study participants will verify that they have ingested the assigned supplement each
                day.

             -  A 35 ml blood sample will be collected.

             -  Study participants will next ingest 26 g of freeze-dried blueberry powder or
                placebo powder in 1.5 cups of water (with Equal packets available to improve taste
                as desired).

             -  A simple questionnaire will be used for study participants to indicate muscle
                soreness (DOMS).

             -  Study participants will complete a symptom log, which will include questions on
                digestive and mental health (heartburn, bloating, diarrhea, nausea, energy levels,
                ability to focus, etc.). Study participants will indicate responses using a
                12-point Likert scale, with 1 relating to "none at all", 6 "moderate", and 12 "very
                high".

             -  Study participants will be randomized to cycle 75-km on water alone or with bananas
                and water (and this will be revealed after the blood draw). Twenty minutes after
                ingesting the supplement, study participants will start the 75-km cycling time
                trial.

                75-km CYCLING TIME TRIAL

      7:30 am: Start 75-km cycling time trial. Study participants are to complete the 75-km course
      as fast as possible.

        -  Study participants will use their own bicycles on CompuTrainer Pro Model 8001 trainers
           (RacerMate, Seattle, WA). A mountainous 75-km course with moderate difficulty will be
           utilized using the CompuTrainer software system.

        -  Heart rate and rating of perceived exertion (RPE) will be recorded every 30 minutes, and
           workload (watts) continuously monitored using the CompuTrainer MultiRider software
           system (version 3.0, RacerMate, Seattle, WA).

        -  Oxygen consumption, carbon dioxide production, and ventilation will be measured using
           the Cosmed metabolic cart after 16 km and 55 km cycling (through a facemask similar to
           what occurred during baseline testing). Performance will be monitored throughout the
           75-km cycling time trial using percentage of maximal watts to ensure that a full effort
           is being given.

        -  Study participants will consume 3 ml/kg water every 15 min (e.g., about one cup for a 75
           kg cyclist).

        -  If randomized to ingest bananas with water: Study participants will ingest Cavendish
           bananas, with the volume adjusted to 0.2 g carbohydrate/kg body weight every 15 minutes
           (or 0.8 g/kg carbohydrate per hour) during the 75-km time trials. For a 75-kg cyclist,
           fruit intake will be approximately one-half banana every 15 minutes. Bananas will be
           provided by Dole Foods at the appropriate ripening stage (full yellow, stage six). No
           other beverage or food containing energy or nutrients will be allowed during the cycling
           time trials.

           ~10:00-11:30 am: Immediate-post-exercise, 1.5-h recovery blood samples; lunch

        -  Blood samples will be taken from the arm vein immediately after completing the 75-km
           time trial, and then at 1.5-h post-exercise.

        -  Immediately post-exercise, study participants will complete the symptom log.

        -  Study participants will indicate muscle soreness using the DOMS questionnaire
           immediately post-exercise and 1.5-h post-exercise.

        -  Study participants will ingest no food or beverage other than water (7 ml/kg or about
           two cups during the 1.5 h post-exercise period).

        -  Right after the 1.5-h recovery blood sample has been collected, study participants will
           ingest a meal adjusted to 12 kcal/kg body weight. The meal will be prepared by Dole
           Foods and include grilled chicken, rice, corn, green beans, salt, and water.

           ~11:30 am to 3:00 pm: 3-h and 5-h recovery

        -  Additional blood samples and DOMS responses will be collected 3-h and 5-h post-exercise.
           During this time, study participants will rest quietly in the lab.

      LAB VISITS #4 and #5: RECOVERY DAY BLOOD SAMPLES, 7:00 am:

      • Study participants will return to the lab the following two mornings in an overnight fasted
      state at about 7:00 am (~21-h and 45-h after completing the 75-km time trial). Blood samples
      and responses to the DOMS questionnaire will be collected at both lab visits. Study
      participants will ingest the blueberry or placebo powder in the lab on the first recovery day
      following the blood sample collection.
    

Intervention name(s): Blueberry; Placebo; banana; No banana
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): 26 g/day freeze-dried powder, 2 weeks duration; Placebo powder; Acute ingestion of bananas 0.2 g carb/kg every 15 min exercise with water; water only
Other intervention name(s): Placebo
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Randomized parallel group
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: exercise; innate immune function; metabolomics; inflammation