Rhodiola rosea is an herbal root extract used to help cope with stress. Evidence suggests, but has not independently confirmed, modest short-term relief of stress-related mental fatigue, and supports a small endurance boost when taken shortly before exercise. Longevity evidence is laboratory-only, untested in mammals or people. Trial side effects were mild; main risks are mislabeled products, modestly slower liver breakdown of some medicines such as warfarin, and possible over-activation. (Full Review)
| Marker | Target | Why |
|---|---|---|
| INR (warfarin users only) | 0.8–1.2 (standard reference range); track change from pre-Rhodiola INR | Safety check on warfarin effect |
| Perceived Stress Questionnaire or Perceived Stress Scale score | No established target; track change from own baseline | Primary stress outcome |
| Multidimensional Fatigue Inventory (MFI-20) score | No established target; track change from own baseline | Fatigue outcome |
| Salivary cortisol awakening response | No established target; track change from own baseline | Shifted with treatment in burnout |
| Endurance time trial or time to exhaustion | No established target; track change from own baseline | Endurance outcome |
Cadence: Baseline before starting; questionnaires and diary at 2 weeks, 4 weeks and at the end of each course (usually 8–12 weeks); INR 1–2 weeks after starting, changing or stopping the extract; performance test every 4–6 weeks.