Exercise and Cognition Trials
Condition: Alteration of Cognitive Function
Study type: Interventional

Summary: 
      The purpose of this study is to determine whether an acute bout of exercise may temporarily
      enhance cognitive function (such as memory or attention span) by measuring behavioral
      performance on cognitive tests, as well as expression of hormones in circulation associated
      with brain plasticity and stress.
    

Detailed description: 
      This is a randomized experiment consisting of three visits for each participant. Participants
      are determined to be eligible beforehand during a phone screening, in which the various study
      inclusions and exclusions are determined and the Physical Activity Readiness Questionnaire
      for Everyone 2015 (PARQ) is administered.

      In the first visit, various anthropometric data are collected from participants, such as
      height, weight, and waist and hip circumference. The participants' blood pressure is also
      checked for hypertension. The participants are given Dual Energy X-Ray Absorptiometry (DEXA)
      scans to determine total body composition (bone, fat, and fat-free mass) If the participant
      is female, a urine analysis to determine pregnancy is required during the visit before the
      DEXA to ensure safety. Participants are given the Rapid Assessment of Physical Activity
      (RAPA) questionnaire to assess habitual activity levels. The participants' muscle strength is
      also measured using the Biodex System 3, an isokinetic dynamometer. The participants then
      undergo a maximal stress test on a treadmill integrated with a Cardinal Health Metabolic/ECG
      cart using a modified Balke protocol, beginning at 3 mph, 0% grade, and increasing 2.5% grade
      every 3 minutes. The ECG component of the metabolic cart will be used for continuous heart
      rate monitoring as part of the fitness assessment. Cardiorespiratory parameters (VO2,
      ventilation, respiratory rate) will also be measured throughout the test. Blood pressure is
      measured during the last 30 seconds of each exercise stage and the rating of perceived
      exertion (RPE) using the Borg 6 to 20 scale is obtained during each stage. Subjects are urged
      to give a maximal effort and are pushed until volitional fatigue.

      In the second visit, participants are first given a series of cognitive tests designed to
      quantify such cognitive faculties as visual short-term memory, selective attention,
      processing speed, and verbal fluency. These tests consist of seeing simple images on a
      computer screen, such as a series of colored shapes, and responding using a keypad. A blood
      sample is also collected from the participants to serve as a baseline. The subject is then
      randomized to one of three groups: the first group rests for 30 minutes; the second group
      walks on the treadmill at a mild intensity, defined as maintaining 60% of the heart rate
      observed during the max VO2 from the first visit; the last group walks on the treadmill at a
      hard intensity, defined as maintaining 80% of the heart rate observed during the max VO2 from
      the first visit. The subjects then undergo a second blood draw after cooling down, followed
      immediately by another round of the same cognitive tests. An hour after finishing the
      exercise intervention, the same procedure of blood draw followed by cognitive tests is
      repeated, and an hour after that it is repeated again.

      The third visit must be about 24 hours after the previous visit. Participants have blood
      drawn and one final round of cognitive tests.
    

Intervention name(s): Exercise Challenge
Intervention type(s): Other
Intervention description(s): Participants randomized to an exercise condition will perform treadmill exercise for 30 minutes. Participants will self-select a comfortable walking speed. The treadmill grade will be adjusted to elicit and maintain the target heart rate.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: exercise; cognition; brain-derived neurotrophic factor; insulin-like growth factor 1; cortisol