Study note • PMID 21411610
Carbohydrate ingestion during endurance exercise improves performance in adults.
Low risk + high feasibility for most athletes.
ELI5
In plain language
This study was a systematic review with meta-analysis examining the efficacy of carbohydrate (CHO) ingestion compared with placebo (PLA) on endurance exercise performance in adults. (systematic review / meta-analysis; trained participants).
In this systematic review / meta-analysis, the abstract doesn’t find a clear benefit 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: This study was a systematic review with meta-analysis examining the efficacy of carbohydrate (CHO) ingestion compared with placebo (PLA) on endurance exercise performance in adults.
- • In this systematic review / meta-analysis, the abstract doesn’t find a clear benefit for Time to exhaustion, Time-trial performance.
- • Population: trained participants.
- • Protocol cues (title/abstract): 1 h • 3 h.
Protocol
Protocol (as reported)
- • Intervention/exposure: carbohydrate, carb.
- • Dose/time/duration cues in abstract/title: 1 h • 3 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 helps, and who should skip it
Who it helps
- • Athletes similar to the study population (trained 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 skip
- • 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: systematic review / meta-analysis (placebo-controlled).
- • Population: trained participants.
- • Outcomes measured: Time to exhaustion, Time-trial performance, Fat oxidation.
- • Protocol cues mentioned: 1 h • 3 h.
- • Source: PubMed PMID 21411610 (2011) — The Journal of nutrition.
Results excerpt
What the abstract reports
“This study was a systematic review with meta-analysis examining the efficacy of carbohydrate (CHO) ingestion compared with placebo (PLA) on endurance exercise performance in adults.”
Note: excerpts are short; for full context, read the paper.
Limits
Limitations & 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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Performance Science Lab
Research-backed protocols and evidence grades for endurance performance — built for athletes.
Fueling performance research
Fueling is performance, not just health: the right carbs at the right time change outcomes.
Carbohydrate fueling for long runs: a protocol you can practice
Evidence-informed protocol: Carbohydrate fueling for long runs: a protocol you can practice. Practical steps, who it helps, and what to watch out for.
Time to exhaustion research for endurance athletes
A lab outcome that can still guide training: it often tracks fatigue resistance.
Time-trial performance research for endurance athletes
Practical performance outcome used in many studies: closer to racing than lab-only metrics.