The Impact of Sucrose Ingestion During Exercise on Liver and Muscle Glycogen Concentration.
- Conditions
- Liver and Muscle Glycogen Use During Exercise.
- Interventions
- Dietary Supplement: Glucose ingestionDietary Supplement: Sucrose ingestion
- Registration Number
- NCT02110836
- Lead Sponsor
- Javier Gonzalez, PhD
- Brief Summary
Carbohydrate is stored in the body as glycogen, which is mainly found in the liver and muscle. During endurance exercise, muscle glycogen is used as fuel for the working muscles and liver glycogen is broken down to provide glucose to maintain blood glucose (sugar) levels. Both liver and muscle glycogen are important for the ability to perform intense/prolonged endurance exercise. Therefore, nutritional strategies which can maximise the availability of glycogen in muscle and liver can benefit endurance exercise capacity.
The carbohydrates typically found in sports drinks are glucose and sometimes fructose. If glucose only is ingested during exercise, then the maximum rate at which can be absorbed from the intestine into the blood stream is \~1 g/min. However, if different sources of carbohydrate (fructose) are used, which are absorbed through a different pathway, absorption of carbohydrate can be up to \~1.8 g/min. With more carbohydrate available as a fuel, this translates into an improvement in performance.
Sucrose is a naturally occurring sugar that is made up of a single glucose and single fructose molecule. Therefore, theoretically, this can use the two different pathways of absorption and also maximise carbohydrate delivery. It is not yet known however, what impact this has on our liver and muscle glycogen stores during exercise. Therefore the aim of this study is to assess whether sucrose ingestion influences liver and muscle glycogen depletion during endurance exercise.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Male
- Target Recruitment
- 14
- Healthy
- Male
- 18 - 35 years of age
- Endurance trained cyclist/triathlete
- VO2 max ≥ 50 ml/kg/min
- Use of medication
- Smoking
- Metabolic disorders
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Glucose ingestion Glucose ingestion Glucose ingestion during exercise at a rate of 1.8 g/min. Sucrose ingestion Sucrose ingestion Sucrose ingestion during exercise at a rate of 1.8 g/min.
- Primary Outcome Measures
Name Time Method Change in liver glycogen concentration 3 hours The change in liver glycogen concentration will be determined pre-to-post 3 h of exercise using 13C magnetic resonance spectroscopy.
- Secondary Outcome Measures
Name Time Method Plasma glucose concentration. 3 hours Plasma glucose concentrations will be determined every 30 min during 3 h of exercise.
Plasma non-esterified fatty acid concentration 3 hours Plasma non-esterified fatty acid concentrations will be determined every 30 min during 3 h of exercise.
Indirect calorimetry 3 hours Measurements of oxygen consumption, carbon dioxide production and respiratory exchange ratio through indirect calorimetry measured every 30 minutes during exercise.
Change in intramyocellular lipid concentration 3 hours The change in intramyocellular lipid concentration will be determined pre-to-post 3 h of exercise using 1H magnetic resonance spectroscopy.
Plasma lactate concentration 3 hours Plasma lactate concentrations will be determined every 30 min during 3 h of exercise.
Muscle glycogen concentration 3 hours The change in muscle glycogen concentration will be determined pre-to-post 3 h of exercise using 13C magnetic resonance spectroscopy.
Trial Locations
- Locations (1)
Northumbria University
🇬🇧Newcastle upon Tyne, Tyne and Wear, United Kingdom