Study note • PMID 24343835
Effects of protein in combination with carbohydrate supplements on acute or repeat endurance exercise performance: a systematic review.
Low risk + high feasibility for most athletes.
ELI5
In plain language
The purpose of this review was to provide a systematic and comprehensive analysis of the literature that tested the hypothesis that protein supplements, when combined with carbohydrate, directly enhance… (systematic review / meta-analysis; n=11 trained athletes).
In this systematic review / meta-analysis, the abstract suggests a positive relationship with 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: The purpose of this review was to provide a systematic and comprehensive analysis of the literature that tested the hypothesis that protein supplements, when combined with carbohydrate, directly enhance…
- • In this systematic review / meta-analysis, the abstract suggests a positive relationship with Time to exhaustion, Time-trial performance.
- • Population: n=11 trained athletes.
- • Protocol cues: abstract may omit dose/timing; use the full paper to replicate accurately.
Protocol
Protocol (as reported)
- • Intervention/exposure: carbohydrate, carb.
- • Dose/time/duration: abstract doesn’t include enough detail; use the full paper’s methods section.
- • 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 (n=11 trained athletes) 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.
- • Population: n=11 trained athletes.
- • Outcomes measured: Time to exhaustion, Time-trial performance, Fat oxidation.
- • Source: PubMed PMID 24343835 (2014) — Sports medicine (Auckland, N.Z.).
Results excerpt
What the abstract reports
“When carbohydrate is delivered at optimal rates during or after endurance exercise, protein supplements appear to have no direct endurance performance enhancing effect.”
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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