Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT03400423 |
| Other study ID # |
Acute Exercise and Caffeine |
| Secondary ID |
|
| Status |
Completed |
| Phase |
Phase 4
|
| First received |
|
| Last updated |
|
| Start date |
February 1, 2018 |
| Est. completion date |
August 1, 2019 |
Study information
| Verified date |
January 2018 |
| Source |
Western University, Canada |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
The effects of moderate intensity aerobic exercise and caffeine ingestion on cognition (more
specifically working memory) in non-caffeine drinker and caffeine drinkers will be examined.
The non-caffeine drinkers will be recruited for two visits, whereas, the caffeine drinkers
will be recruited for three visits. The study involves a baseline assessment of cognition and
examines the effects of exercise and caffeine. Finally the caffeine group will consist of a
baseline and intervention assessment when deprived of caffeine (overnight abstinence). The
exercise intervention is to complete 20-minutes of moderate intensity exercise (brisk walk)
while the caffeine condition is to consume 1.2 mg/kg of caffeine. Immediately following both
intervention the n-back assessment will be conducted.
Description:
Phase 1 will assess non-caffeine consumers
Phase 1 will utilize a within subjects counter-balanced design. Previous to arrival for phase
1, participants will be asked to abstain from alcohol and drugs for at least 18 hours
previous. Participants will be urged to arrive at the same time for each visit. Upon arrival
to the Exercise and Health Psychology lab (located in room 408 of the Arthur and Sonia Labatt
Health Science Building at Western University) participants will be given the letter of
information, and asked to sign the informed consent form. After consent, participants will
also be asked to complete a demographic survey, PAR-Q readiness for exercise, Godin
Leisure-Time Exercise Questionnaire, caffeine consumption questionnaire-R (CCQ-R) and a
caffeine withdrawal questionnaire (CWSQ). Vitals (heart rate and blood pressure) will be
assessed following the completion of the questionnaires as well as post intervention in the
seated position. Prior to evaluation on the N-back task (cognitive memory task described
below) a practice stage with be conducted until the participant can consistently score 75% or
higher on three consecutive trials to eliminate a learning effect. After establishing test
familiarity, a baseline cognition score will be conducted through the n-back assessment. The
subject will then be given a 5-minute break (i.e., to use the lavatory). Following the break,
the participants will be randomized into either moderate intensity exercise or caffeine
ingestion group. The interventions are as follows; Moderate Intensity Exercise will consist
of a 20-minute bout of moderate intensity aerobic exercise. Exercise will consist of a
2-minute warm-up, followed by 15 minutes of walking at a rate, which will allow you to reach
2/3 of your max heart rate ((220-age)x0.6) followed by a 3-minute cool down on a treadmill
(together equaling 20 minutes). HR will be monitored through heart rate monitors worn by the
participants. The caffeine ingestion group will ingest 1.2 mg/kg of caffeine orally in powder
form with water to drink, after ingestion of caffeine participants will wait 20 minutes to
ensure peak plasma levels. The participants both the exercise group and the caffeine
ingestion group will be asked to refrain from conversation. The post intervention assessment
will begin within two minutes of the completion of either intervention. The second visit of
phase I will take place the following day at the same time (if possible). During the second
visit the participant's will complete the pre caffeine or pre exercise questionnaire, the
CWSQ and vitals will be monitored pre and post intervention. The participants will
participate in the intervention that they have not received on the first visit (for example,
if the participant received caffeine ingestion on the first visit the participant will
receive moderate intensity aerobic exercise on the second visit). Within two minutes of
completion the post treatment N-back task assessment will begin.
Phases 2 and 3 will assess caffeine consumers (phase 3 in an acutely deprived state)
Phase 2 will utilize a within subjects counter-balanced design. Previous to arrival for phase
2 participants will be asked to keep consumption of caffeine to a regular dose (morning
coffee) on the day of testing, abstain from alcohol and drugs for at least 18 hours prior to
testing. Participants will be urged to arrive at the same time for each visit. Upon arrival
to the Exercise and Health Psychology lab (located in room 408 of the Arthur and Sonia Labatt
Health Science Building at Western University) participants will be given the letter of
information, and asked to sign the informed consent form. Participants will also be asked to
complete a demographic survey, PAR-Q readiness for exercise, Godin Leisure-Time Exercise
Questionnaire, CCQ-R, and the CWSQ. Vitals (heart rate and blood pressure) will be assessed
following the completion of the questionnaires as well as post intervention in the seated
position. Prior to evaluation on the N-back task (cognitive memory task described below) a
practice stage with be conducted until the participant can consistently score 75% or higher
on three consecutive trials to eliminate a learning effect. After establishing familiarity, a
baseline cognition score will be conducted through the n-back assessment. The subject will
then be given a 5 minute break (i.e., to use the lavatory). Following the break the
participants will be randomized into either the moderate intensity exercise or caffeine
ingestion group. The interventions are as followed; Moderate Intensity Exercise will consist
of a 20-minute bout of moderate intensity aerobic exercise. Exercise will consist of a
2-minute warm-up, followed by 15 minutes of walking at a rate, which will allow you to reach
2/3 of your max heart rate (moderate intensity exercise= (220-age) x 0.6), and then a
3-minute cool down on a treadmill (together equaling 20 minutes). HR will be monitored
through heart rate monitors worn by the participants. The caffeine ingestion group will
ingest 1.2 mg/kg of caffeine in powder form with water to drink, after ingestion of caffeine
participants will wait 20 minutes to ensure peak plasma levels.The participants in both the,
exercise group and caffeine ingestion group will be asked to refrain from conversation. The
post intervention assessment will begin within two minutes of the completion of either
intervention. The second visit of phase I will take place the following day at the same time
(if possible). During the second visit the participant's will complete the pre caffeine or
pre exercise questionnaire, the CWSQ and vitals will be monitored pre and post intervention.
The participants will participate in the intervention that they have not received on the
first visit (for example, if the participant received caffeine ingestion on the first visit
the participant will receive moderate intensity aerobic exercise on the second visit). Within
two minutes of completion the post treatment N-back task assessment will begin.
Prior to arrival for phase 3, participants will be asked to refrain from caffeine for at
least 12 hours, and abstain from alcohol and drugs for at least 18 hours prior to testing.
Phase 3 will utilize the same participants as phase 2, but they will be examined in a
caffeine-deprived state (12 hours) for baseline N-back scores the CWSQ will also be
administered. Participants will then be randomized into either the caffeine ingestion group
or exercise treatment group where post intervention N-back scores will be obtained.
Participants will be asked to complete the same pre-intervention questionnaires as the
previous phase. Vitals (heart rate and blood pressure) will be assessed pre and post
intervention. Caffeine abstinence will be validated through self-report with the use of
deception (participants being told that their saliva sample is being tested for the presence
of caffeine).
N-back task explanation: Three tasks will be administered to subjects for each treatment
condition (after caffeine administration and after exercise). The 1-back, 2-back, and 3-back
cognitive tests will assess working memory by measuring both the percentage of correct
responses, as well as reaction time. In these 5 minute tasks, a letter will appear on a
computer screen for an interval of 500ms, followed by a 2000ms blank screen interstimulus
(totaling 120 letters/5 minutes). Participants will be instructed to click the left button of
a computer mouse as soon as a target appears, and to keep in mind both the speed and accuracy
components of the task. In the 1-back condition, the target is defined as a letter flashing
that is the same as the one preceding it. For example, "x, interstimulus, x" would be the
target. In the 2-back condition, the target is defined as a letter appearing that is the same
as what preceded it 2 letters before. For example, "a, interstimulus, b, interstimulus, a",
would be the target. In the 3-back condition, the target is defined as a letter appearing
that is the same as what preceded it 3 letters before. For example, "a, interstimulus, b,
interstimulus, c, interstimulus, a", would be the target. All tasks call into action the
participant's working memory abilities, as a measure of cognition.
