Interactive Roles of Cardiorespiratory Fitness and Adiposity on Glucose and Vascular Control After Physical Inactivity

NCT06842225 | Not Yet Recruiting DMC

• 1 other identifier: 02290-1R15HL177798-01
• Study Type: interventional
• Target: 48
• Locations: 1 country
• Sites: 1

Brief Summary

The far-reaching negative health effects of the reduced physical activity (RPA) epidemic are often overlooked by the general population and health professionals. Short-term RPA induces cardiometabolic dysfunction, including impaired glucose control and vascular function, that may precede disease development. The impact of existing health status on RPA-induced cardiometabolic dysfunction and recovery of impaired glucose control following RPA is unexplored. Thus, the investigators' objectives are 1) to investigate the effect of existing health status (cardiorespiratory fitness and adiposity) on the recovery of impaired glucose control following a period of RPA and 2) to determine the role of vascular function as a mechanism of impaired glucose control. The investigators' final objective is to 3) expose undergraduate students to meritorious biomedical clinical research methods. The investigators have piloted the clinical research methods and analysis with undergraduate researcher associates and are well-prepared to complete this proposal. Preliminary data show that low cardiorespiratory fitness and/or high adiposity impair the recovery of glucose control following short-term RPA. Thus, the investigators aim to examine the interactive role of health status (cardiorespiratory fitness and adiposity) on the ability to recover impaired glucose control following short-term RPA. The investigators also seek to examine changes in vascular function as a mechanism of recovery of impaired glucose control following a return to normal PA. The investigators will recruit men and women with divergent health status (cardiorespiratory fitness and adiposity) to examine glucose control and vascular function during 7-d of normal PA, 7-d of RPA, and 7-d of resumption of normal RA. Continuous glucose monitoring and oral glucose tolerance tests will be performed to assess glucose control. Increases in vascular shear stress induced by passive leg movement and central arterial stiffness will be measured to assess vascular function.

Conditions

Metabolic Disorders; Physical Inactivity; Vascular Disease Risk

Keywords

physical activity; glucose control; vascular function

Outcome Measures

Primary Outcomes (4)

• Changes in Daily Physical Activity

  Accelerometers will be use to measure changes in daily physical activity during the three week study duration. Accelerometer data to be reported includes: daily number of steps, daily sitting time, daily stepping time, total sedentary time, and activity score.

  3 weeks

• Oral Glucose Tolerance Test (OGTT)

  On the morning of each OGTT, participants will arrive in the lab following an 8-10 h fast. An indwelling intravenous catheter will be placed into a forearm vein. Baseline (0 min) blood samples will be collected into heparinized evacuated tubes following 15 min of seated rest. Participants will consume a volume of glucose tolerance beverage containing 1 gram of glucose/kg of lean body mass to control for expected differences in body and fat mass between individuals. Participants will remain rested in the reclined position for the duration of the OGTT. Blood samples will be collected at 30, 60, 90, and 120 min post drink. Heparinized blood samples will be utilized to assess blood glucose using the Contour Next blood glucose monitoring system.

  Days 0, 7, and 14

• Continuous Glucose Monitoring

  Participants will wear CGM sensors for the duration of the study, with the first sensor being placed on day -7 and a second sensor replacing it on day 0. Data will be exported and quality-checked data will be imported into the IGlu Application in R Studio and analyzed using the following parameters: Night hours set from 10 PM to 7 AM; Time above (high) set to 140 mg/dL; Time above (low) set to 120 mg/dL; Time in range set to 70-120 mg/dL; Time below (high) set to 70 mg/dL; Time below (low) set to 54 mg/dL; Data reported using this software includes weekly and daily means, standard deviations (SD), coefficient of variations (CV), medians, time below range \< 54 mg/dL (TBR \<54), time below range \< 70 mg/dL (TBR \<70), time in range 70-120 mg/dL (TIR 70-120), time above range \>120 mg/dL (TAR \>120), time above range \>140 mg/dL (TAR \>140), mean amplitude of glycemic excursions (MAGE), and area under the curve (AUC).

  3 weeks

• Femoral Artery Blood Flow

  Passive leg movement (PLM)-induced reactive hyperemia will be measured to assess peripheral vascular function. Briefly, the PLM technique involves passive movement of the leg to elicit a reactive hyperemic response measured by high-frequency ultrasonographic imaging. Diameter and blood velocity in the common femoral artery will be measured following 15 minutes of seated rest using a 5 to 12MHz multi-frequency linear array transducer connected to a high-resolution ultrasound. Arterial diameter and velocity will be recorded continuously for 60 seconds at baseline and 60 seconds during PLM. Femoral artery blood flow and shear rate (estimate of shear stress) will be calculated from arterial diameter and blood velocity measurements.

  Days 0, 7, and 14

Secondary Outcomes (6)

• Fat Mass and Fat-Free Mass

  Days 0, 7, and 14

• Height

  Days 0

• Central Arterial Stiffness

  Days 0, 7, and 14

• Central Arterial Blood Pressure

  Days 0, 7, and 14

• Blood Lipids

  Days 0, 7, and 14

Study Arms (1)

Reduced physical activity

EXPERIMENTAL

We will recruit, screen, and enroll eligible participants (18-40y) across the following four groups: high CRF/low adiposity, high CRF/high adiposity; low CRF/low adiposity; low CRF/high adiposity. Each participant will undergo a three-week study. For the first week, participants will be instructed to maintain their normal level of physical activity. For the second week, participants' schedules will be examined, and strategies designed to reduce steps (by at least 2000 steps) and physical activity. To assist in reducing walking and increased sitting, participants will be given seated electric scooters to use whenever they normally walk. The scooters will be returned on the third week, and participants will be instructed to resume their normal physical activity. During the entire three weeks, participants will wear a continuous glucose monitor and a physical activity monitor.

Other: reduced physical activity

Interventions

reduced physical activity OTHER

Each participant will undergo a three-week study. For the first week (day -7 to day 0), participants will be instructed to maintain their normal level of physical activity. For the second week (day 0 to day 7), the reduced physical activity (RPA) week, participants' schedules will be examined, and strategies designed to reduce steps (by at least 2000 steps) and physical activity (by taking elevators and short-cuts, etc.) by increasing sitting time \>10%. To assist in reducing walking and increased sitting, participants will be given seated electric scooters to use whenever they normally walk. The scooters will be returned on the third week (day 7 to day 14), and participants will be instructed to resume their normal physical activity. During the entire three weeks, participants will wear a continuous glucose monitor (CGM) and a physical activity monitor (ActivPal).

Reduced physical activity

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Males and females 18 to 40 years of age.
• Ability to safely ride an electric scooter (e-scooter) for at least 10 minutes.
• Active (\>7000 steps per day, walking \> 1 mile a day outside)
• Stable body weight for at least 1 year
• aerobic fitness level, CRF is \< 9 and \>14 METS
• Visceral adipose tissue \<130 cm2 or ≥130 cm2 for men and \<100 cm2 or ≥100 cm for women

You may not qualify if:

• Any injury preventing them from exercising regularly at the time of the screening.
• Implantable defibrillator or pacemaker
• Active cancer
• Alcohol or drug abuse
• Use of an assistive walking device
• Presence of significant signs/symptoms of cardiovascular, metabolic, or pulmonary disease (determined from the American College of Sports Medicine (ACSM) Health History Questionnaire)
• Daily vitamin consumption of \> 500mg per day during the study
• Acetaminophen or aspirin use during the study

Sponsors & Collaborators

• Miami University: lead

Study Sites (1)

Phillips Hall

Oxford, Ohio, 45056, United States

Location

MeSH Terms

Conditions

Metabolic Diseases; Sedentary Behavior; Motor Activity

Condition Hierarchy (Ancestors)

Nutritional and Metabolic Diseases; Behavior

Central Study Contacts

Kevin Ballard, PhD

CONTACT

513-529-9247; ballarkd@miamioh.edu

Paul Reidy, PhD

CONTACT

reidypt@miamioh.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: We will recruit, screen, and enroll eligible participants (18-40y) across the following four groups: high CRF/low adiposity; high CRF/high adiposity; low CRF/low adiposity; low CRF/high adiposity.

Study Record Dates

• First Submitted: February 7, 2025
• First Posted: February 24, 2025
• Study Start: June 1, 2025
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 30, 2029
• Last Updated: February 24, 2025

Record last verified: 2025-02

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)