Examining Time and Nutrient Dependent Effects of Aerobic Exercise on Energy Metabolism in Adults With Overweight and Obesity
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Overweight and Obesity
- Sponsor
- University of Colorado, Denver
- Enrollment
- 20
- Locations
- 1
- Primary Endpoint
- Exercise Energy Expenditure (kcals)
- Status
- Active, not recruiting
- Last Updated
- 4 months ago
Overview
Brief Summary
This study plans to learn more about metabolic responses to aerobic exercise at different times of the day (morning or evening) under fasting versus fed conditions.
Detailed Description
This study plans to learn more about metabolic responses to aerobic exercise at different times of the day (morning or evening) under fasting versus fed conditions. Specifically, the investigators will explore the effect of fasted and fed AM and PM aerobic exercise on exercise energy expenditure and substrate oxidation, explore the effect of fasted and fed AM and PM aerobic exercise on plasma metabolites and lipids, and explore the effect of fasted-AM and Fasted-PM on 24h energy expenditure, 24h substrate metabolism, 24h glucose, and 24h profiles of hormonal regulators of energy metabolism
Investigators
Eligibility Criteria
Inclusion Criteria
- •Age 18-40 years
- •Body Mass Index 18.5-\<40 kg/m2
- •Recreationally active: defined as \>100 minutes per week of voluntary exercise at moderate intensity or greater and \>60 min per day of total habitual physical activity (i.e., work related, transportation related) at moderate intensity or greater, over the past 3 months.
- •No self-report of acute or chronic disease (cardiovascular disease (CVD), diabetes, pulmonary, gastrointestinal disorders, and orthopedic problems in particular).
- •No plans to relocate within the next 6 months.
- •No plans for extended travel (\>2 weeks) within the next 6 months.
- •Live or work within 30 minutes of the AHWC (exceptions may be made at the discretion of the Study PI on a case-by-case basis for highly motivated subjects).
- •Capable and willing to give informed consent, understand exclusion criteria, and adhere to study conditions.
- •Have a primary care physician (or are willing to establish care with a primary care physician prior to study enrollment) to address medical issues which may arise during screening or study procedures.
- •No contraindications to exercise or limitations on ability to be physically active.
Exclusion Criteria
- •Diastolic blood pressure \>100 mmHG, systolic blood pressure \>160 mmHG, or resting heart rate \>100 bpm as measured in duplicate on the screening visit after 5 minutes of rest in a seated position.
- •Diabetes (fasting glucose \>/=126 mg/dL or Hemoglobin A1C \>/=6.5%) as measured during the screening visit.
- •Undiagnosed hypo- or hyper-thyroidism (TSH outside of the normal range as measured during the screening visit) or history of uncontrolled thyroid disorder. History of thyroid disease or current thyroid disease treated with a stable medication regimen for at least 6 months is acceptable.
- •Hematocrit, white blood cell count or platelets significantly outside the normal reference range as measured on the screening visit.
- •Triglycerides \>400 mg/dL as measured on the screening visit.
- •LDL cholesterol \>200 mg/dL as measured on the screening visit.
- •Abnormal resting electrocardiogram (ECG) as measured on the screening visit: serious arrhythmias, including multifocal PVC's, frequent PVC's (defined as 10 or more per min), ventricular tachycardia (defined as runs of 3 or more successive PVC's), or sustained atrial tachyarrhythmia; 2nd or 3rd degree A-V block, QTc interval \> 480 msec or other significant conduction defects.
- •Presence or history of any metabolic or chronic health problems which would affect appetite, food intake, energy metabolism, or ability to participate in exercise: CVD, peripheral vascular disease, cerebrovascular disease, significant cardiac arrhythmias or cardiac valve disease, diabetes, uncontrolled hyper- or hypothyroidism, uncontrolled hypertension, cancer (within the last 5 years, except skin cancer or other cancers considered cured with excellent prognosis), HIV infection, significant renal, musculoskeletal, neurologic, hematologic, or psychiatric disease.
- •Significant gastrointestinal disorders including: chronic malabsorptive conditions, peptic ulcer disease, Crohn's disease, Ulcerative Colitis, chronic diarrhea, or active gallbladder disease.
- •Significant pulmonary disorders including: chronic obstructive pulmonary disease (COPD), interstitial lung disease, cystic fibrosis, or uncontrolled asthma.
Outcomes
Primary Outcomes
Exercise Energy Expenditure (kcals)
Time Frame: Fasted-AM Day 5, Fed-AM Day 5, Fasted-PM Day 5, Fed-PM Day 5
On Day 5 of each condition, participants will complete a 45-minute exercise test on the treadmill to compare exercise energy expenditure and fat oxidation between. O2 and CO2 content of expired air will be measured continuously by open circuit spirometry and averaged every minute using an automated online system (TrueMax 2400; Parvo-Medics, Sandy, UT). Exercise energy expenditure will be determined from minute-by-minute values, measured in kcals.
Substrate Oxidation (Respiratory Quotient)
Time Frame: Fasted-AM Day 5, Fed-AM Day 5, Fasted-PM Day 5, Fed-PM Day 5
On Day 5 of each condition, participants will complete a 45-minute exercise test on the treadmill to compare exercise energy expenditure and fat oxidation between. O2 and CO2 content of expired air will be measured continuously by open circuit spirometry and averaged every minute using an automated online system (TrueMax 2400; Parvo-Medics, Sandy, UT). Substrate Oxidation will be determined from minute-by-minute values, measured in respiratory quotient.