Study note • PMID 34453013
Carbohydrate and Protein Co-Ingestion Postexercise Does Not Improve Next-Day Performance in Trained Cyclists.
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: randomized trial.
- • 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
Supplementing postexercise carbohydrate (CHO) intake with protein has been suggested to enhance recovery from endurance exercise. (randomized trial; trained participants).
The abstract doesn’t indicate a clear change in 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: Supplementing postexercise carbohydrate (CHO) intake with protein has been suggested to enhance recovery from endurance exercise.
- • The abstract doesn’t indicate a clear change in Time-trial performance under the tested conditions.
- • Population: trained participants.
- • Protocol cues: abstract may omit dose/timing; use the full paper to replicate accurately.
Protocol
Protocol (as reported)
- • Intervention/exposure: carbohydrate, carb (vs comparison group).
- • 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 may help, and who should be cautious
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 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: randomized trial (double-blind).
- • Population: trained participants.
- • Comparator: comparison group.
- • Outcomes measured: Time to exhaustion, Time-trial performance, Fat oxidation.
- • Source: PubMed PMID 34453013 (2021) — International journal of sport nutrition and exercise metabolism.
Results excerpt
What the abstract reports
“Insulin AUC was lower in CHO (18.1 +/- 7.7 nmol.L-1.2 hr-1) compared with CHO + PRO and CHO + PROH (24.6 +/- 12.4 vs.”
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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