An interventional study of Traditional Exercise Training and Daily Microbursts of Activity in Health Behavior, sponsored by University of Colorado, Denver. Completed at 1 site in United States. Open to participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-11-18.
Sponsored by University of Colorado, Denver · Not applicable, Interventional, and Basic science
Population studies suggest that time spent in sedentary behaviors is associated with all-cause mortality including obesity, diabetes, and cardiovascular diseases, independent of time spent in exercise. Frequent interruptions to sedentary time are however beneficially associated with metabolic health outcomes, even in individuals who exercise regularly. The goal is to use integrative approach to understand the biological mechanisms that underlie these associations in a longitudinal intervention study in overweight sedentary adults. The investigators believe that the proposed study will provide an initial evidence base for the health benefits of breaking up prolonged sitting with short bursts of activity. This innovative strategy may be more effective at combating the adverse effects of sedentary behaviors than more traditional approaches.
To compare the effects of 6-weeks of microbursts of moderate-intensity activity to a calorically equivalent single bout of 45 minutes of moderate-intensity exercise training, both performed 5 days per week for a total of 45 minutes, in free-living sedentary overweight adults on:
Aim 1: plasma inflammatory and cardiometabolic health biomarkers in association with total energy expenditure and time spent in sedentary behaviors.
H1: Microbursts of activity will result in higher daily energy expenditure and lower time spent sedentary, as respectively measured with doubly labeled water and accelerometry, than traditional exercise training. This will be associated with healthier inflammatory Interleukin 1 alpha (IL1a), Interleukin 6 (IL6), Interleukin 10 (IL10), Tumour Necrosis Factor alpha (TNFa) and cardiometabolic (triglycerides, cholesterol, C-Reactive Protein (CRP), High-density lipoprotein (HDL), and Low-density lipoprotein (LDL) profiles compared to those obtained with traditional exercise training program.
Aim 2: 24-hr total fat and carbohydrate oxidation, exogenous carbohydrate oxidation, dietary fat trafficking between oxidation and incorporation into muscle lipid fractions, and mitochondrial function.
H2: Both one single continuous bout and microbouts of activity will increase 24-hr total (whole-room calorimetry) and dietary (D31-palmitate) fat oxidation due to greater mitochondrial lipid oxidation (high resolution respirometry) and lower incorporation of dietary fatty acid into muscle lipid fractions (D31-palmitate), as compared to baseline sedentary control condition. Microbouts of activity will further result in greater increases in 24-hr total (whole-room calorimetry) and exogenous (U-13C6 glucose) carbohydrate oxidation and in mitochondrial carbohydrate-linked oxidation, than traditional isocaloric exercise training.
Aim 3: Whole-body insulin sensitivity and daily glucose mean and variability. H3: Both one single continuous bout and microbouts of activity will improve whole-body insulin sensitivity Intravenous Glucose Tolerance Test (IVGTT) compared to the baseline sedentary condition, but the improvement will likely be higher with the microbouts of activity. However, only the microbouts of activity will improve postprandial glycemia and the daily oscillations in glucose level as measured by CGM.
Exploratory aim: Self-perceived appetite and hunger.
University of Colorado, Denver is the lead sponsor of 1,499 studies on the registry; 315 are open to participants now.
Of its 139 completed or terminated interventional studies of FDA-regulated products, 89 (64%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion criteria:
Participants will be asked to perform moderate-intensity exercise (brisk walking) for 45 minutes for 5 days/week for 6 weeks. This intervention corresponds to the current recommendations.
Behavioral: Traditional Exercise Training
Participants will be asked to break up their sedentary activities of daily living for 5-minutes every hour for 9 hours, 5 days/week, by brisk walking for 6 weeks.
Behavioral: Daily Microbursts of Activity
Participants will be asked to perform moderate-intensity exercise (brisk walking) for 45 minutes for 5 days/week for 6 weeks. This intervention corresponds to the current recommendations.
Participants will be asked to break up their sedentary activities of daily living for 5-minutes every hour for 9 hours, 5 days/week, by brisk walking for 6 weeks.
Changes in sedentary time as measured by ActiPAL
Over each 2 week period, participants will be instructed to wear an ActiPAL (PALTechnologies: Glasgow, Scotland) activity monitor on their right leg. Participants will be instructed to wear the monitors at all times except when sleeping or participating in water-based activities. The time-stamped "event" data file from the activPAL software will be used to determine time spent sitting/lying, standing and stepping per day.
Time frame: weeks 1-2 and weeks 5-6
Changes in insulin sensitivity
Insulin sensitivity will be determined via an insulin modified frequently sampled intra-venous glucose tolerance test (IVGTT). After baseline samples, intravenous glucose (0.3 g/kg) will be infused over 1 minute, followed by insulin at 0.03 U/kg, 20 minutes after glucose administration. Blood samples will be frequently sampled over 5 hours, and insulin sensitivity will be calculated using the Bergman minimal model.
Time frame: Week 2 and week 8
Postprandial glycemia
Incremental area under the curve of plasma glucose concentration measured in fasting and every hour for 14 hours.
Time frame: Week 2 and week 8
Changes in total energy expenditure (TEE)
Total energy expenditure (TEE) will be measured before and at the end of the intervention using doubly labeled water (DLW) over a 10-day period, as previously described (31). Subjects will ingest premixed 2g/kg total body water (TBW), estimated as 73% of fat free mass) dose of DLW composed of 0.2 and 0.15 g/kg estimated TBW of H218O and 2H2O, respectively. Urine samples will be collected in duplicate on days 0, 6, 8 and 10. 2H and 18O enrichment will be determined in urine samples by isotope ratio mass spectrometry (Delta V Advantage IRMS)
Time frame: week 1-2 and week 5-6
Changes in Moderate-to-vigorous physical activity as measured by ActiGraph
Over the same 10-day period, participants will be instructed to wear an Actigraph GT3X+ accelerometer (Actigraph, LLC, Fort Walton Beach, FL) on their hip. Participants will be instructed to wear the monitors at all times except when sleeping or participating in water-based activities.
Time frame: weeks 1-6
24hr substrate oxidation and energy expenditure
Gas exchange are measured for 24hr by whole room calorimetry and nitrogen excretion is measured in the urines collected for 24hr. 24hr energy expenditure is then calculated using 24hr VCO2, 24hr VO2 and 24hr urinary nitrogen excretion with the Weir equation. 24hr carbohydrate, fat and protein oxidation are calculated using 24hr VCO2, 24hr VO2 and 24hr urinary nitrogen excretion with the Frayn equation.
Time frame: Week 2 and week 8
Changes in Dietary Carbohydrate Oxidation
After the investigators have shown the subjects the procedure, subjects will collect their own hourly breath sampling for CO2 by blowing through a straw into two 15ml Vacutainers. Breath CO2 will be sampled directly from the Vacutainer with a syringe, and 13CO2 /12CO2 measured with IRMS.
Time frame: week 2 and week 8
Changes in Dietary Fat Oxidation
Hourly urine sampling will be collected by the subjects for 24 hours and stored in 5mL cryovials at -20C until further analysis. To measure 2 hour fat oxidation, 2 hour/1 hour ratios from urine samples will be analyzed, as above described for the doubly labeled water method. The oxidation rate of glucose/water will be calculated from the cumulative recovery of 2 hours in total body water (TBW) as detailed previously.
Time frame: week 2 and week 8
Postprandial insulinemia
Incremental area under the curve of plasma insulin concentration measured in fasting and every hour for 14 hours.
Time frame: Week 2 and week 8
Postprandial NEFA
Incremental area under the curve of plasma NEFA as measured in fasting state and every hour for 14 hours.
Time frame: Week 2 and week 8
Postprandial triglyceridemia
Incremental area under the curve of plasma TG as measured in fasting state and every hour for 14 hours.
Time frame: Week 2 and week 8
Daily glucose mean and oscillation
Daily interstitial glucose mean and oscillations as measured by continuous glucose monitoring for 14 consecutive days.
Time frame: Weeks 1-2 and weeks 5-6
Changes in Mitochondria function
Freshly isolated skeletal muscle biopsies will be cut into small samples, the fibre bundles separated mechanically and partially teased apart and permeabilised. Small samples (2-5mg) will be added to the 2ml chamber of an Oroboros high-resolution respirometer with a mitochondrial respiration buffer. With the addition of several substrates, different states will be reached to analyse mitochondrial function. Pyruvate, malate and glutamate will be added as substrates to examine respiration through Complex I, succinate will be used to examine respiration through Complex II and octanoylcarnitine will be used to examine respiration through the electron-transferring flavoprotein, ETF.
Time frame: week 2 and week 7
Changes in plasma inflammatory markers
Fasting blood samples will be obtained for the measurements of Interleukin 1 alpha (IL1a), Interleukin 6 (IL6), Interleukin 10 (IL10), Tumour Necrosis Factor alpha (TNFa) and cardiometabolic (triglycerides, cholesterol, C-Reactive Protein (CRP).
Time frame: Week 2 and week 8
changes in plasma total cholesterol, HDL and LDL
Fasting plasma blood draw for the measurement of total cholesterol, HDL and LDL.
Time frame: Week 2 and week 8
Self-perceived appetite and hunger
Self-perceived hunger, satiety and prospective food consumption as measured by visual analog scale before and after standard breakfast, lunch, and dinner.
Time frame: Week 2 and week 8
Plan to share: No
No publications or documents are linked to this record.
This study is completed, as verified in Nov 2024. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University of Colorado, Denver