Study note • PMID 1757304
Carbohydrate feedings before, during, or in combination improve cycling endurance performance.
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
This study examined the effects of no carbohydrate (PP), preexercise carbohydrate feeding (CP), carbohydrate feedings during exercise (PC), and the combination of carbohydrate feedings before and during exercise (CC)… (controlled study; well-trained cyclists).
The abstract suggests a positive effect on Time to exhaustion, 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: This study examined the effects of no carbohydrate (PP), preexercise carbohydrate feeding (CP), carbohydrate feedings during exercise (PC), and the combination of carbohydrate feedings before and during exercise (CC)…
- • The abstract suggests a positive effect on Time to exhaustion, Time-trial performance under the tested conditions.
- • Population: well-trained cyclists.
- • Protocol cues (title/abstract): 30 min • 120 min • 201 min.
Protocol
Protocol (as reported)
- • Intervention/exposure: carbohydrate, carb.
- • Dose/time/duration cues in abstract/title: 30 min • 120 min • 201 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 (well-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.
- • Population: well-trained cyclists.
- • Outcomes measured: Time to exhaustion, Time-trial performance, Fat oxidation.
- • Protocol cues mentioned: 30 min • 120 min • 201 min.
- • Source: PubMed PMID 1757304 (1991) — Journal of applied physiology (Bethesda, Md. : 1985).
Results excerpt
What the abstract reports
“Nine well-trained cyclists exercised at 70% of maximal O2 uptake until exhaustion.”
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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Performance Science Lab
Research summaries for endurance athletes, with study context, practical protocols, and clear limitations.
Open guideFueling performance research
Fueling is performance, not just health: the right carbs at the right time change outcomes.
Open guideTime to exhaustion research for endurance athletes
A lab outcome that can still guide training: it often tracks fatigue resistance.
Open guide