Fructose and sucrose boost carbohydrate burning during exercise
What it found
In 10 trained male cyclists, drinking a mix of glucose plus fructose or glucose plus sucrose during 3 hours of cycling led to higher rates of carbohydrate oxidation than glucose alone.
The two mixes worked about equally well.
What they found
Studies in people
Carbohydrate oxidation rates
Peak carbohydrate oxidation from the drinks was 1.40 g per minute with glucose plus fructose and 1.29 g per minute with glucose plus sucrose, compared with 0.96 g per minute with glucose alone. The two sugar mixes were not significantly different from each other.
Gut distress
Total upper gut distress scores were higher with glucose alone than with water, glucose plus fructose, or glucose plus sucrose. The authors say this suggests less carbohydrate builds up in the gut when fructose or sucrose is included.
Blood markers
Plasma lactate rose more with glucose plus fructose and glucose plus sucrose than with glucose alone or water. Plasma glucose and insulin did not differ significantly among the three carbohydrate drinks.
Intestinal damage marker
A marker of intestinal damage did not change significantly over time in any group, and there were no differences between the drinks.
What the authors conclude
“We conclude that fructose co-ingestion (0.6 g∙min-1) with glucose (1.2 g∙min-1) provided either as a monosaccharide or as sucrose strongly increases exogenous carbohydrate oxidation rates during prolonged exercise in trained cyclists.”
Also in their conclusions
- They conclude that fructose co-ingestion, provided either as a monosaccharide or as sucrose, strongly increases exogenous carbohydrate oxidation rates during prolonged exercise in trained cyclists.
- They state that when ingesting large amounts of carbohydrates during exercise, co-ingestion of fructose or sucrose will lower GI distress and increase the capacity for exogenous carbohydrate oxidation.
- They suggest that both fructose and sucrose represent proper ingredients for sports drinks to further increase exogenous carbohydrate oxidation rates during exercise.
How it was done
The authors wanted to see whether fructose taken with glucose, either as pure fructose or as part of sucrose, increases the amount of carbohydrate the body burns during exercise. They also wanted to know if sucrose is as effective as pure fructose for this.
Ten trained male cyclists cycled for 180 minutes at 50% of their maximal workload on four separate occasions. During each session they drank one of four drinks: glucose only, glucose plus fructose, glucose plus sucrose, or water. The researchers measured how much carbohydrate came from the drinks and was burned.
What it can’t tell you
- The study did not measure exercise performance, so it cannot show whether these drinks improve cycling speed or endurance.
- The results are from 10 trained male cyclists, so they may not apply to other people or to other types of exercise.
- The study cannot rule out that sucrose might be less effective than pure fructose at higher carbohydrate intakes than the ones tested here.
Who paid
- Conflicts
- The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.
- Authors work at
- Maastricht University Medical Centre, The Netherlands; Loughborough University, UK
The paper
- Title
- Fructose and Sucrose Intake Increase Exogenous Carbohydrate Oxidation during Exercise
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Trommelen J, Fuchs CJ, Beelen M, et al (2017). Fructose and Sucrose Intake Increase Exogenous Carbohydrate Oxidation during Exercise. Nutrients. doi:10.3390/nu9020167Free full textPubMed 28230742DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error