RedMonkey Sports Acid Block®

Six-dimension breakdown

Why this scored 44/100

RedMonkey Sports Acid Block is a US-patented (US 10,213,453) alkaline-mineral caplet marketed to cyclists and endurance athletes for 'raising lactate threshold' and 'combatting exercise-induced body acidosis.' The scientific premise is a decades-old misconception: lactate itself does not cause muscle fatigue or acidosis in the way endurance-supplement marketing implies. Robergs 2004 (American Journal of Physiology) formally corrected the lactate-acidosis story — the H+ ions responsible for exercise acidosis come from ATP hydrolysis, not from lactate, and lactate itself is actually a buffered fuel substrate that the liver and other muscles readily oxidize. Buffering blood pH with oral alkaline minerals has some evidence for high-intensity performance (sodium bicarbonate at 300 mg/kg has RCT support for 1-7 minute all-out efforts — Peart 2012 meta-analysis), but the effect is small and specific to buffering acute high-intensity work, not to 'raising lactate threshold.' A US patent validates novelty, not efficacy. Marketing claim 'proven that raising your Lactate Threshold will allow you to ride stronger for longer' misrepresents the underlying physiology. Autofail on unverified_medical_claim for the specific 'raises lactate threshold via oral buffer' claim.

Evidence & sources

The Vyvata score's Evidence dimension measures the quality of published RCT support for a product's active ingredients at the label dose. Our source hierarchy: double-blind RCTs in MEDLINE-indexed journals > single-blind RCTs > open-label trials > observational studies > mechanism papers > N=1 case studies (anecdotes). Predatory journals and manufacturer-authored studies without independent replication are weighted down.

Product-specific evidence citations for this item are embedded in the analysis text on the "Analysis" tab. For the full framework and evidence hierarchy, see the methodology page.

How to read the Evidence dimension

• 80–100: Multiple double-blind RCTs in indexed journals directly testing this product OR the exact ingredients at the exact dose.
• 60–79: Single double-blind RCT + supporting ingredient literature at the studied dose.
• 40–59: Open-label trials + ingredient literature; no product-specific double-blind evidence.
• 20–39: Ingredient literature only; no product-specific trials or trials in predatory venues.
• 0–19: No credible evidence base or unverifiable claims.

FAQ data has not been generated for this product yet. See the site FAQ for general questions.

Customer reviews

All the data we have on this product

Every VSF-related metafield surfaced verbatim. Nothing hidden. If you spot data that looks wrong, let us know.

VSF score

44 / 100

Tier

Rejected

Category

Supplements

Subcategory

energy metabolic

Last scored

August 30, 2026

Third-party certifications

None on record at time of scoring

Vendor

RedMonkey Sports

Product type

Vitamins & Supplements

Tags

RedMonkey Sports, Shopify Collective

Every score is set from the published rubric, audit-logged, and rescored whenever new evidence emerges (published trials, updated labels, third-party testing releases). Every vendor is scored on the same criteria — no pay-to-play. See our editorial-independence disclosure for the full policy, including brands with an editorial relationship to this site.