Trial Outcomes & Findings for Aerobic Exercise and Cerebrovascular Function (NCT NCT03803904)

NCT ID: NCT03803904

Last Updated: 2026-05-07

Results Overview

CVR will be assessed using 5% CO2 challenge while continuously acquiring MR images. This method has been extensively used and is the most suitable vasoactive stimulus. Briefly, the CO2 air (5% CO2, 21% O2 and 74% N2) will be administered via an air bag with a valve to switch between room air and CO2 air in the bag. A mouth piece and a nose clip will be used to achieve mouth-only breathing. A research staff member will be inside the magnet room throughout the experiment to switch the valve and to monitor the subject. Physiologic parameters, including end-tidal (Et) CO2 and breathing rate will be monitored and recorded during the experiments. The percentage of change in Blood-Oxygen-Level-Dependent (BOLD) signal per millimeter of mercury is the metric used to quantify CVR. It measures how much the BOLD signal changes in response to a 1 mmHg change in the end-tidal partial pressure of carbon dioxide.

Recruitment status

ACTIVE_NOT_RECRUITING

Study phase

NA

Target enrollment

37 participants

Primary outcome timeframe

At the Pre-intervention assessment and 12-weeks following at the Post intervention assessment

Results posted on

2026-05-07

Participant Flow

Participant milestones

Participant milestones
Measure
Spin
The intervention will take place three times a week for 12 weeks and will be led by a qualified instructor (an Exercise Physiologist with five years of experience conducting the intervention). The duration of each session will be increased by 1-2 minutes to a maximum time of 45 minutes per session based on the progression of the participants and the recommendation of the instructor. Because participants are initially sedentary and detrained, exercise intensity will begin at low levels (50% of maximal heart rate reserve, HRR) but will be increased by 5% every week (if deemed necessary by the instructor) to a maximum of 75% maximal HRR.
Control
Participants in the control group will be equalized (frequency and duration) to the Spin group for contact and monitoring. As such they will report to the same facility and interact with the same experienced interventionist; however instead of progressive Spin exercise they will participate in sessions focused on balance and stretching. Similar to the aerobic intervention, these exercises will take place in a group setting and heart rate will be consistently monitored during each session to verify heart rate does not reach 50% HRR.
Overall Study
STARTED
22
15
Overall Study
COMPLETED
15
7
Overall Study
NOT COMPLETED
7
8

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Aerobic Exercise and Cerebrovascular Function

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Spin
n=22 Participants
The intervention will take place three times a week for 12 weeks and will be led by a qualified instructor (an Exercise Physiologist with five years of experience conducting the intervention). The duration of each session will be increased by 1-2 minutes to a maximum time of 45 minutes per session based on the progression of the participants and the recommendation of the instructor. Because participants are initially sedentary and detrained, exercise intensity will begin at low levels (50% of maximal heart rate reserve, HRR) but will be increased by 5% every week (if deemed necessary by the instructor) to a maximum of 75% maximal HRR.
Control
n=15 Participants
Participants in the control group will be equalized (frequency and duration) to the Spin group for contact and monitoring. As such they will report to the same facility and interact with the same experienced interventionist; however instead of progressive Spin exercise they will participate in sessions focused on balance and stretching. Similar to the aerobic intervention, these exercises will take place in a group setting and heart rate will be consistently monitored during each session to verify heart rate does not reach 50% HRR.
Total
n=37 Participants
Total of all reporting groups
Age, Categorical
<=18 years
0 Participants
n=54 Participants
0 Participants
n=60 Participants
0 Participants
n=114 Participants
Age, Categorical
Between 18 and 65 years
2 Participants
n=54 Participants
0 Participants
n=60 Participants
2 Participants
n=114 Participants
Age, Categorical
>=65 years
20 Participants
n=54 Participants
15 Participants
n=60 Participants
35 Participants
n=114 Participants
Age, Continuous
70.18 years
STANDARD_DEVIATION 3.61 • n=54 Participants
72.88 years
STANDARD_DEVIATION 4.36 • n=60 Participants
71.04 years
STANDARD_DEVIATION 3.98 • n=114 Participants
Sex: Female, Male
Female
14 Participants
n=54 Participants
9 Participants
n=60 Participants
23 Participants
n=114 Participants
Sex: Female, Male
Male
8 Participants
n=54 Participants
6 Participants
n=60 Participants
14 Participants
n=114 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=54 Participants
0 Participants
n=60 Participants
0 Participants
n=114 Participants
Race (NIH/OMB)
Asian
0 Participants
n=54 Participants
0 Participants
n=60 Participants
0 Participants
n=114 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=54 Participants
0 Participants
n=60 Participants
0 Participants
n=114 Participants
Race (NIH/OMB)
Black or African American
4 Participants
n=54 Participants
3 Participants
n=60 Participants
7 Participants
n=114 Participants
Race (NIH/OMB)
White
18 Participants
n=54 Participants
12 Participants
n=60 Participants
30 Participants
n=114 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=54 Participants
0 Participants
n=60 Participants
0 Participants
n=114 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=54 Participants
0 Participants
n=60 Participants
0 Participants
n=114 Participants
Region of Enrollment
United States
22 Participants
n=54 Participants
15 Participants
n=60 Participants
37 Participants
n=114 Participants

PRIMARY outcome

Timeframe: At the Pre-intervention assessment and 12-weeks following at the Post intervention assessment

CVR will be assessed using 5% CO2 challenge while continuously acquiring MR images. This method has been extensively used and is the most suitable vasoactive stimulus. Briefly, the CO2 air (5% CO2, 21% O2 and 74% N2) will be administered via an air bag with a valve to switch between room air and CO2 air in the bag. A mouth piece and a nose clip will be used to achieve mouth-only breathing. A research staff member will be inside the magnet room throughout the experiment to switch the valve and to monitor the subject. Physiologic parameters, including end-tidal (Et) CO2 and breathing rate will be monitored and recorded during the experiments. The percentage of change in Blood-Oxygen-Level-Dependent (BOLD) signal per millimeter of mercury is the metric used to quantify CVR. It measures how much the BOLD signal changes in response to a 1 mmHg change in the end-tidal partial pressure of carbon dioxide.

Outcome measures

Outcome measures
Measure
Spin
n=15 Participants
The intervention will take place three times a week for 12 weeks and will be led by a qualified instructor (an Exercise Physiologist with five years of experience conducting the intervention). The duration of each session will be increased by 1-2 minutes to a maximum time of 45 minutes per session based on the progression of the participants and the recommendation of the instructor. Because participants are initially sedentary and detrained, exercise intensity will begin at low levels (50% of maximal heart rate reserve, HRR) but will be increased by 5% every week (if deemed necessary by the instructor) to a maximum of 75% maximal HRR.
Control
n=7 Participants
Active Comparator: Control Participants in the control group will be equalized (frequency and duration) to the Spin group for contact and monitoring. As such they will report to the same facility and interact with the same experienced interventionist; however instead of progressive Spin exercise they will participate in sessions focused on balance and stretching. Similar to the aerobic intervention, these exercises will take place in a group setting and heart rate will be consistently monitored during each session to verify heart rate does not reach 50% HRR.
Cerebrovascular Reactivity (CVR) Using a Hypercapnic CO2 Response Test Change
0.120 percentage of change BOLD/mmHg
Standard Deviation 0.057
0.133 percentage of change BOLD/mmHg
Standard Deviation 0.036

Adverse Events

Spin

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Control

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Joe Nocera

Department of Veterans Affairs

Phone: 404 321 6111

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place