All articles
What is a good VO2 max? What the number means, by age and sex
Welltory promo code: what the app costs, what stays free forever, and 20–36% off for readers
Blood pressure
Spoon theory explained: what the spoons really measure, and where the metaphor runs out
Energy-Limiting Conditions (ELC)
Body battery explained: what Garmin's score measures, and how to read your own energy
Blood oxygen level explained: what SpO2 and oxygen saturation mean
Blood Oxygen
Melatonin: why the dose matters less than the timing
Circadian rhythm
Heart arrhythmia and palpitations: what a racing, fluttering, or irregular heartbeat means — and when it's dangerous
The pain scale everyone shares: what the McGill chart actually measures
Adrenaline dumps in POTS: what the surge feels like, how long it lasts, and why the next day is worse
POTS & Dysautonomia
HRV monitors: chest strap, wrist wearable, or phone camera — what actually measures heart rate variability
HRV
Why am I bloated all the time? Constant bloating, its causes, and what your gut is telling you
Cortisol
Sarcopenia symptoms: the muscle loss that starts in your 30s, and the two levers that reverse it
HRV