Overfeeding and Exercise
Conditions
Brief summary
Rationale: Body weight is not well regulated in all individuals. In an obesogenic environment, where overeating is common, some individuals are more prone to weight gain and therefore overweight than others. Yet, the reasons behind this are unclear. Resistant individuals often have higher physical activity levels (PALs). It seems that - at higher levels of physical activity and therefore energy expenditure - satiety signals are more precisely regulated, making one better at matching energy intake with expenditure. In other words, active people may not overeat where sedentary people would. However, this does not explain the differences in weight gain observed when subjects all have to overeat (imposed overfeeding). It could be that active people are better able to cope metabolically with the extra calories because of already higher levels of carbohydrate and fat oxidation compared to their inactive counterparts. Objectives: 1/ To study the effects of overfeeding (normal diet composition) on substrate balance and oxidation and more specifically fat balance and oxidation; 2/ to study the effects of exercise and training on fat oxidation during overfeeding (normal diet composition). Study design: This controlled intervention study will follow a cross-over design. Each subject will spend 5 nights and 4 days in a respiration chamber on two occasions, separated by a 10-week training period.
Interventions
OTHERoverfeeding + exercise pre-training
BEHAVIORALfitness training
OTHERoverfeeding + exercise post-training
Sponsors
Maastricht University Medical Center
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
MALE
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* Caucasians * Male * Healthy * 18-30 years * BMI 21-27.5 kg.m-2 * Sedentary lifestyle: the following serve as (non-strict) guidelines: Low category of activity according to the short version of the International Physical Activity Questionnaire (IPAQ); VO2max (ml.kg-1.min-1) below: 45 - AGE (yrs) / 3 corresponding to a fitness category below fair (i.e. poor or very poor) as defined by Schvartz and Reibold. For example for an 18 year-old male, VO2max below 39 ml.kg-1.min-1. * Stable body weight (\<5% change in the last 6 months)
Exclusion criteria
* Following a (weight-loss) diet * Using medications * Smoking * Consuming more than 3 units of alcohol per day * Diagnosed with any chronic diseases known to affect energy metabolism (intake/expenditure) such as diabetes, cardiovascular disease, cancer, or thyroid disease. * Trained or regularly physically active (according to the IPAQ)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in 24-hour fat balance with overfeeding after training | Baseline and 3 months | Day3 24-hour fat balance (calculated as the difference between metabolisable fat intake and fat oxidation measured by indirect calorimetry in respiration chamber) after training compared to baseline (=before training) |
| Change in 24-hour fat balance with overfeeding and exercise after training | Baseline and 3 months | Day4 24-hour fat balance (calculated as the difference between metabolisable fat intake and fat oxidation measured by indirect calorimetry in respiration chamber) after training compared to baseline (=before training) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in 24-hour fat balance with overfeeding and exercise in inactive men | Day 3 and day 4 (baseline stay in respiration chamber) | Fat balance (calculated as the difference between metabolisable fat intake and fat oxidation) on day 4 compared to day 3 at baseline |
| Change in 24-hour fat oxidation with overfeeding and exercise in active men | Day 3 and day 4 (stay in respiration chamber at 3 months) | Fat oxidation measured by indirect calorimetry in respiration chamber on day 4 compared to day 3 after the training period |
| Change in 24-hour carbohydrate oxidation with overfeeding and exercise in active men | Day 3 and day 4 (stay in respiration chamber at 3 months) | Carbohydrate oxidation measured by indirect calorimetry in respiration chamber on day 4 compared to day 3 after the training period |
| Change in 24-hour fat balance with overfeeding and exercise in active men | Day 3 and day 4 (stay in respiration chamber at 3 months) | Fat balance (calculated as the difference between metabolisable fat intake and fat oxidation) on day 4 compared to day 3 after the training period |
| Change in 24-hour carbohydrate oxidation with overfeeding after training | Baseline and 3 months | Day3 24-hour carbohydrate oxidation measured by indirect calorimetry in respiration chamber after training compared to baseline (=before training) |
| Change in 24-hour carbohydrate oxidation with overfeeding and exercise after training | Baseline and 3 months | Day4 24-hour carbohydrate oxidation measured by indirect calorimetry in respiration chamber after training compared to baseline (=before training) |
| Change in fat oxidation after training assessed in energy balance | Baseline and 3 months | — |
| Change in carbohydrate oxidation after training assessed in energy balance | Baseline and 3 months | — |
| Change in 24-hour fat oxidation with overfeeding and exercise in inactive men | Day 3 and day 4 (baseline stay in respiration chamber) | Fat oxidation measured by indirect calorimetry in respiration chamber on day 4 compared to day 3 at baseline |
| Change in energy expenditure in free-living conditions | Baseline and 3 months | Energy expenditure measured over 14 days using doubly-labeled water and two accelerometers (TracmorD and Actigraph GT3X) |
| Energy expenditure with overfeeding in active men | 4 days at 3 months | Energy expenditure measured by indirect calorimetry during a 4-day stay in respiration chamber, with overfeeding on days 2 to 4, after a 10-week fitness training. |
| Insulin sensitivity | Baseline, 2 weeks (pre-training), 3 months (post-training) | Based on glucose and insulin plasma concentrations from oral glucose tolerance test, where blood is collected in fasted state at t=0, 30, 60, 90 and 120min after a glucose drink is ingested) |
| adipocyte size | Baseline, 2 weeks (pre-training), 3 months (post-training) | Fat biopsy taken these time points |
| Genes involved in lipid metabolism | Baseline, 2 weeks (pre-training), 3 months (post-training) | Using fat biopsies: analysis of genes involved in the lipolytic pathway \[ATGL (PNPLA2), HSL (S660/565/563), CGI-58, G0S2, PLIN1, AQP7, GK\], in insulin signaling/glucose metabolism \[GLUT4, IRS1/IRS2, AKT, pAKT (S473), pIRS1 (S1101)\], in fatty acid metabolism \[CD36, FABP4 (aP2), FASN, CPT1a/1b, CPT2, ACADL/ACADVL/ACADS/ACADM, ACOX1, OXPHOS (complex I-V), PPAR(α/βδ/γ), PGC1a, PGC1b, SIRT1, AMPK (pAMPK)\], and in DAG/ceramide metabolism \[DGAT 1/2, GPAT1/GPAM, PLC, SPTLC1 and SPTLC2, CERK, ASAH1 and ASAH2 |
| Change in body composition | Baseline and 3 months | Measured using body weight, underwater weighing and deuterium dilution, before and after the fitness training |
| Change in cardiorespiratory fitness | Baseline, after 6-7 weeks of training and 3 months | Cardiorespiratory fitness estimated as the maximal oxygen uptake (VO2max) assessed using an incremental test on a bicycle ergometer |
| Validity of Actigraph GT3X accelerometer | Two 14-day periods (baseline and 3 months) | The Actigraph GT3X accelerometer is worn by each subject twice for 14 days and will be validated against the doubly labeled water technique and compared to the tracmorD accelerometer |
| Energy expenditure with overfeeding in inactive men | 4 days at baseline | Energy expenditure measured by indirect calorimetry during a 4-day stay in respiration chamber, with overfeeding on days 2 to 4. |
| Change in 24-hour carbohydrate oxidation with overfeeding and exercise in inactive men | Day 3 and day 4 (baseline stay in respiration chamber) | Carbohydrate oxidation measured by indirect calorimetry in respiration chamber on day 4 compared to day 3 at baseline |
Countries
Netherlands
Outcome results
None listed