Carbohydrate Oxidation and Glycogen Utilization During and Following Exercise
Conditions
Keywords
carbohydrate, glycogen, glucose
Brief summary
Carbohydrates are an integral component of sports nutrition. Providing carbohydrate (CHO) during exercise delays the onset of fatigue and improves exercise performance by maintaining high rates of CHO oxidation. Traditionally, glucose, or glucose polymers have been the preferential CHO source found in sports drinks. However, during the intestinal absorption of large amounts of glucose (\>1.2 g/min), sodium-dependent glucose transporters (SGLT1) may become fully saturated, potentially limiting the rate of exogenous CHO oxidation. In an effort to evade this limitation, research has suggested using multiple transportable carbohydrates in the composition of sports drinks. Multiple transportable carbohydrates are combinations of simple sugars that use different intestinal transporters during the absorption process. Ingesting multiple transportable carbohydrates may enhance the capacity for total intestinal CHO absorption, leading to an increase in the rate of exogenous CHO oxidation. Our purpose will be to examine the disaccharide sucrose in it's ability to provide exogenous fuel during and following prolonged exercise.
Interventions
DIETARY_SUPPLEMENTCarbohydrate ingestion
Various types of carbohydrate ingested during and following exercise
Sponsors
Maastricht University Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
MALE
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy * Male * 18 - 40 years of age * Endurance trained cyclist/triathlete * VO2 max ≥ 50 ml/kg/min * BMI \< 25 kg/m2
Exclusion criteria
* Use of medication * Smoking
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Exogenous carbohydrate oxidation rate (Part A) | 0 min during trials 1-3 | Carbohydrate oxidation as measured by breath samples |
| Endogenous carbohydrate oxidation (Part A) | 0 min during trials 1-3 | endogenous carbohydrate oxidation as measured through breath samples during trials 1-3 |
| Glycogen utilization (Part B) | immediately post exercise (~90min), during trials 4-6 | Glycogen utilization measured through a muscle biopsy sample at post (\ 90 min), 3 and 6 h post exercise. Part B; trials 4-6. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Indirect calorimetry (Part A) | every 30 min up to 180 min during trials 1-3 | Measurements of VO2, VCO2 and RER through indirect calorimetry measured every 30 minutes during trials 1-3 |
| Plasma glucose | every 30 min up to 180 min during trials 1-6 | Plasma glucose measurements |
| Plasma insulin | every 30 minutes up to 180 min during trials 1-6 | plasma insulin measurements |
Countries
Netherlands
Contacts
Primary ContactNaomi Cermak, Ph.D.
Outcome results
None listed