Dietary Nitrate and Muscle Power With Aging
Condition: Aging; Sarcopenia
MeSH terms: Sarcopenia
Study type: Interventional

Summary: 
      The purpose of this study is to see if drinking beetroot juice (BRJ) is beneficial for aging
      patients. We hope to determine the effect of BRJ on exercise performance. BRJ improves
      exercise performance in athletes and normal people. We are trying to determine if BRJ
      improves exercise performance in aging patients. We will be comparing the effects of BRJ
      versus the effects of a placebo (BRJ without the nitrates that are naturally occurring in
      beets and other similar foods). It is thought that the benefits of BRJ may come from its
      natural nitrate content. Although BRJ is available for purchase in grocery stores, for the
      purposes of this study it is considered investigational, which means that it has not been
      approved as a medical therapy.
    

Detailed description: 
      This study consists of two parts separated by a 14 day wash-out. Subjects will be randomly
      assigned to receive either the BRJ or placebo during the first part. During the second part
      they will receive the opposite of what they had during the first part. This is considered a
      double-blind study, which means neither the subjects nor the investigators will know what
      form (BRJ or placebo) a subject is receives.

      Study Visit One (Screening) 1-2 hours

      The purpose of the screening visit is to explain all aspects of the study. It will also
      determine if subjects can participate in the study. Subjects will provide a complete medical
      history and undergo a physical exam. They will have their blood drawn (about 1.5 teaspoons)
      and provide a urine sample. They will also practice the entire neuromuscular function
      exercise test. During this test, the strength of their muscles will be determined by having
      them kick, push and/or pull back as hard as you can while their leg is strapped to an
      exercise device. A vital signs monitor will measure your blood pressure, heart rate, and
      rhythm.

      During the remainder of the study subjects will be instructed to consume their normal diet.
      However, they will be asked to avoid eating foods high in nitrate such as beets, spinach, and
      collard greens the evening before each visit. They will be asked to refrain from the use of
      antibacterial mouthwash, such as Listerine or Cepacol, during the study. Chewing gum,
      alcohol, and food and drinks containing caffeine (coffee, tea, chocolate, and soft drinks)
      should be avoided 24 hours prior to each visit. They will be asked to fast for 12 hour prior
      to each study visit.

      Study Visit Two - Approximately 5 hours

      At the beginning of this visit a catheter (small, flexible, sterile plastic tube) will be
      placed through a vein in one of the subject's arms. This is for collection of blood samples.
      Blood will be drawn four times during this visit. Each draw will be 6 mL or about 1.2
      teaspoons. The first blood draw will check nitrate and nitrite levels. They will then have a
      breath test to check nitric oxide. They will then drink 140 mL (about 2/3 of a cup) of BRJ
      (or placebo). Blood and breath samples will be obtained every hour. Heart rate and blood
      pressure will be measured at the same times the blood and breath samples are obtained.
      Subjects will then rest quietly in a private room for about 2 hours after ingestion of BRJ
      (or placebo) then will perform:

        -  The neuromuscular function test that was practiced during the screening visit.

        -  After completing the exercise test they will undergo a muscle biopsy of their thigh
           muscle. First, the area will be sterilized and numbed with an injection. Next, a small
           incision (about ¼ inch) will be made and a small biopsy needle will be used to collect a
           small sample of your muscle (about the size of a pencil eraser). This will be performed
           on the leg opposite of that used during the neuromuscular test.

        -  One final blood and breath sample will then be obtained.

        -  Subjects will then be provided a 7 day supply of BRJ (or placebo) and will continue to
           drink two bottles (about 5 oz) every morning.

        -  Subjects will also be provided with an activity tracker. This will be worn at the hip
           during all waking hours except when bathing or swimming. This monitor will measure total
           activity time and sedentary time.

      Study Visit Three - 1-2 hours

      Subjects will return to the research center with the empty BRJ bottles. At this visit a
      single blood (1.2 teaspoon) and breath sample will be collected. Subjects will then complete
      a questionnaire to rate how tired they felt during the previous week. They will be provided
      another 7 day supply of BRJ (or placebo) and will continue to drink two bottles every
      morning.

      Study Visit Four - Approximately 5 hours Subjects will return to the research center and
      undergo the same procedures as they did in Study Visit Two. They will also complete a
      questionnaire that will rate how tired they felt during the previous week.

      Washout After visit four subjects will undergo a 14 day washout period where they will not
      drink the BRJ (or placebo). There are no dietary restrictions at this time; subjects may
      consume caffeine, alcohol, gum, mouthwash, etc. Subjects will then repeat Study Visits Two,
      Three, and Four again. However, during this they will be given the opposite form of BRJ you
      had received before.

      Study Visit Five Subjects will repeat the procedures completed during Study Visit Two.

      Study Visit Six Subjects will repeat the procedures completed during Study Visit Three.

      Study Visit Seven Subjects will repeat the procedures completed during Study Visit Four.
    

Intervention name(s): placebo; nitrate
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): 2 x 70 mL concentrated beet root juice depleted of nitrate per day for 14 days.; 2 x 70 mL concentrated beet root juice per day for 14 days.
Other intervention name(s): Beet It Sport Nitrate 400 placebo; Beet It Sport Nitrate 400
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Double-blind, placebo-controlled, crossover
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: nitric oxide