Enzyme-derived deer velvet extract linked to fatigue relief and endurance gain in chronic fatigue

Exercise Evidence: RCT · n=100 · 8-week randomized controlled trial, placebo-controlled, double-blind 2026-07-23

A randomized controlled trial of 100 adults with chronic fatigue syndrome found that 8 weeks of YC-1101 (an enzymatically derived deer velvet extract) significantly reduced subjective fatigue and improved exercise endurance compared to placebo.

Chronic Fatigue Syndrome significantly reduces quality of life in working-age populations, and many people turn to nutritional supplements seeking relief. This 8-week randomized controlled trial enrolled 100 patients with CFS and assigned them to receive either YC-1101 (an enzyme-derived deer velvet extract) or placebo.

Subjective fatigue was measured using the Multidimensional Fatigue Inventory at baseline, week 4, and week 8; physical and functional outcomes were also tracked. Compared with placebo, YC-1101 significantly improved Factor 1 (general and physical fatigue) on the MFI at weeks 4 and 8 (group-by-time interaction p = 0.002), and participants reported meaningful improvements on the specific items "I feel tired" and "I get tired easily" (p = 0.014 each). The supplement also showed benefit on the Fatigue Severity Scale, improving fatigue-related motivation and functional interference at weeks 4 and 8 (p = 0.040). Exercise capacity improved in the YC-1101 group—distance to exhaustion was significantly greater than placebo (p = 0.031)—and lactate levels showed a significant group-by-time interaction at week 8 (p = 0.049), suggesting an effect on metabolic fatigue markers. No adverse events were reported, and safety profiles were equivalent between groups. The evidence is limited to a single trial of modest size, so replication in larger, longer-term studies would strengthen confidence.

Takeaway

Enzyme-derived deer velvet extract may help reduce subjective fatigue and support endurance capacity in adults with chronic fatigue syndrome, though a single trial of 100 participants is not yet definitive.

The improvement in exercise distance to exhaustion—a measurable, objective outcome—is noteworthy because many fatigue interventions rely only on self-report. The shift in lactate levels at week 8 hints at a biological mechanism: the extract may influence how muscles process metabolic byproducts during exertion. Notably, both subjective fatigue (via MFI and FSS) and exercise capacity moved in the same direction, which suggests the effect isn't purely psychological. The trial did exclude statistical outliers from the exhaustion analysis, which is a minor methodological concern—the true effect size may be somewhat different. Eight weeks is a short intervention window; it's unknown whether benefit persists beyond the trial period or whether tolerance develops. Previous preclinical work on YC-1101 exists, but this is among the first human clinical evidence, making it preliminary and worthy of follow-up but not yet a standard recommendation.

Takeaway · Cadence

If you have chronic fatigue and are already working with your healthcare provider, you might consider asking whether a deer velvet extract trial fits your situation—though this research is too early to replace standard fatigue management. Pairing any new supplement with consistent sleep routines, gentle movement, and stress monitoring will give you the clearest picture of what helps. The energy gain reported by participants came over 8 weeks, so consistent use matters if you do try it.

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References

Efficacy and Safety of Enzyme-Derived Deer Velvet Extract Supplementation on Adults with Chronic Fatigue: a Randomized, Placebo-Controlled, Double-Blind Trial. — Journal of microbiology and biotechnology (Read the original)

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