Study note • PMID 15212750
Carbohydrate intake during exercise and 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: review.
- • Population relevance: mixed/unclear athlete specificity.
- • Consistency: single-study evidence.
- • Practical recommendation depends on tolerance, context, and whether it protects training consistency.
ELI5
In plain language
It is generally accepted that carbohydrate (CHO) feeding during exercise can improve endurance capacity (time to exhaustion) and exercise performance during prolonged exercise (>2 h). (review; participants).
In this review, the abstract is mixed or unclear for Time to exhaustion, Time-trial performance. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: It is generally accepted that carbohydrate (CHO) feeding during exercise can improve endurance capacity (time to exhaustion) and exercise performance during prolonged exercise (>2 h).
- • In this review, the abstract is mixed or unclear for Time to exhaustion, Time-trial performance.
- • Population: participants.
- • Protocol cues (title/abstract): 2 h • 1 h.
Protocol
Protocol (as reported)
- • Intervention/exposure: carbohydrate, carb.
- • Dose/time/duration cues in abstract/title: 2 h • 1 h.
- • 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 (participants) 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: review.
- • Population: participants.
- • Outcomes measured: Time to exhaustion, Time-trial performance, Fat oxidation.
- • Protocol cues mentioned: 2 h • 1 h.
- • Source: PubMed PMID 15212750 (2004) — Nutrition (Burbank, Los Angeles County, Calif.).
Results excerpt
What the abstract reports
“In the past few years, studies have investigated ways to optimize CHO delivery and bioavailability.”
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).
- • Reviews and consensus statements mix protocols and populations; recommendations may not match your exact constraints.
- • 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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