Intravenous infusion of H_2-saline suppresses oxidative stress and elevates antioxidant potential in Thoroughbred horses after racing exercise
Yamazaki M, Kusano K, Ishibashi T, Kiuchi M, Koyama K. · 2015.
What kind of evidence is this?
Preclinical
Randomized blinded crossover horse study
Exercise and recovery
Other forms
Mixed or mostly neutral preclinical biomarker signal.
Animal exercise biomarker outcomes.
Methods at a glance
Thoroughbred racehorses after racing exercise.
Small crossover cohorts; group-specific counts were checked in the full article.
Acute post-racing infusion with short laboratory follow-up.
Intravenous infusion of hydrogen-rich saline after racing.
H₂ dissolved in saline.
Approximately 0.6 ppm in the administered saline.
Not applicable.
No oxygen was co-delivered.
Placebo saline in a crossover design.
Outcomes and reported result
Oxidative-stress and antioxidant blood measures.
Some antioxidant measures changed, while the article reports no significant difference for at least one emphasized between-condition comparison.
The full article was checked for methods, intervention details, outcomes, positive and null findings, funding and conflicts. This record does not imply medical efficacy.
A reported association, difference or mechanism is not automatically a clinical benefit. Null findings, outcome type, study design and precision all matter.
Cautions and applicability
Very small animal crossover study with surrogate laboratory outcomes only.
Thoroughbred horses under this post-race infusion protocol.
SYRCLE animal-study tool — preliminary
Some concerns
Randomization and blinding were reported, but the small sample and multiple biomarkers create imprecision and selective-reporting concerns.
Sequence generation checked where reported · Allocation concealment generally unclear · Personnel blinding generally unclear · Outcome-assessor blinding generally unclear · No prospectively registered analysis plan identified
No single-study GRADE certainty rating is assigned. Certainty is assessed by important outcome across a complete eligible evidence set, not by attaching a final grade to one source.
Sources and record status
PMID: 26493164 · DOI: 10.1038/srep15514
A free full article is available through PubMed Central.
Official PubMed Central full article and PubMed bibliographic record; source identity, methods, intervention, results, funding and conflicts checked 10 August 2026.
2026-08-10