Study note • PMID 18202575
Superior endurance performance with ingestion of multiple transportable carbohydrates.
How to use this page
This note summarizes one study record. Check the participants, methods, results, and limitations before applying it to training.
- • Design signal: controlled study.
- • Population relevance: athlete/trained context.
- • Consistency: single-study evidence.
- • Practical recommendation depends on tolerance, context, and whether it protects training consistency.
ELI5
In plain language
INTRODUCTION: The aim of the present study was to investigate the effect of ingesting a glucose plus fructose drink compared with a glucose-only drink (both delivering carbohydrate at a… (controlled study; trained cyclists).
The abstract suggests a positive effect on Time-trial performance under the tested conditions. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: INTRODUCTION: The aim of the present study was to investigate the effect of ingesting a glucose plus fructose drink compared with a glucose-only drink (both delivering carbohydrate at a…
- • The abstract suggests a positive effect on Time-trial performance under the tested conditions.
- • Population: trained cyclists.
- • Protocol cues (title/abstract): 120 min • 1 h • 15 min.
Protocol
Protocol (as reported)
- • Intervention/exposure: carbohydrate, carb (vs placebo).
- • Dose/time/duration cues in abstract/title: 120 min • 1 h • 15 min.
- • Outcomes: Time to exhaustion, Time-trial performance, Fat oxidation.
- • Replication note: abstracts often omit adherence and timing; confirm details before changing training or supplementation.
Fit
Who it may help, and who should be cautious
Who it helps
- • Athletes similar to the study population (trained cyclists) working on fueling.
- • Athletes who can measure Time to exhaustion, Time-trial performance, Fat oxidation with a repeatable workout or time-trial effort.
Who should be cautious
- • If you have symptoms or conditions that make the intervention risky, get professional guidance.
- • If you’re near race day and can’t safely test, defer the experiment.
Methods
What the study actually did
- • Design: controlled study (placebo-controlled).
- • Population: trained cyclists.
- • Comparator: placebo.
- • Outcomes measured: Time to exhaustion, Time-trial performance, Fat oxidation.
- • Protocol cues mentioned: 120 min • 1 h • 15 min.
- • Source: PubMed PMID 18202575 (2008) — Medicine and science in sports and exercise.
Results excerpt
What the abstract reports
“Ingestion of GF resulted in an 8% quicker time to completion during the time trial (4022 s) compared with G (3641 s) and a 19% improvement compared with W (3367 s).”
Note: excerpts are short; for full context, read the paper.
Limits
Limitations and bias
- • Abstract-only summaries can miss critical details (population, protocol, adherence, and context).
- • Single studies often don’t generalize to your event, history, and training load; treat results as a starting point.
- • If your context differs (elite vs recreational; cycling vs running), adjust expectations and be conservative.
- • This is performance information, not medical advice.
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