Study note • PMID 31548903
Effects of almond, dried grape and dried cranberry consumption on endurance exercise performance, recovery and psychomotor speed: protocol of a randomised controlled trial.
Worth trying if it fits your goal and context.
ELI5
In plain language
BACKGROUND: Foods rich in nutrients, such as nitrate, nitrite, L-arginine and polyphenols, can promote the synthesis of nitric oxide (NO), which may induce ergogenic effects on endurance exercise performance. (randomized trial; trained triathletes).
Effects on Time-trial performance are mixed or unclear from the abstract alone. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: BACKGROUND: Foods rich in nutrients, such as nitrate, nitrite, L-arginine and polyphenols, can promote the synthesis of nitric oxide (NO), which may induce ergogenic effects on endurance exercise performance.
- • Effects on Time-trial performance are mixed or unclear from the abstract alone.
- • Population: trained triathletes.
- • Protocol cues (full paper): 30 g/day • 50 g/day • 2 weeks • 4 weeks • 6 months.
Protocol
Protocol (as reported)
- • Intervention/exposure: taper.
- • Dose/time/duration cues found in the full paper: 30 g/day • 50 g/day • 2 weeks • 4 weeks • 6 months.
- • Outcomes: Time-trial performance.
- • 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 triathletes) working on tapering.
- • Athletes who can measure Time-trial performance 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: randomized trial (randomized, single-blind, parallel groups).
- • Population: trained triathletes.
- • Outcomes measured: Time-trial performance.
- • Protocol cues mentioned: 4 weeks • 5 min.
- • Source: PubMed PMID 31548903 (2019) — BMJ open sport & exercise medicine.
Full paper
What the full paper adds
- • Design features (paper): randomized, single-blind, parallel groups.
- • Participants (paper): trained triathletes.
- • More protocol detail (paper): 30 g/day • 50 g/day • 2 weeks • 4 weeks • 6 months.
Results excerpt
What the abstract reports
“TRIAL REGISTRATION NUMBER: ACTRN12618000360213.”
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).
- • 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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