Heart & nervous system
Understand what your heart rate, rhythm, and recovery reveal about your health — and what keeps your heart and nervous system resilient.
Most read
August 11, 2026
What is a good HRV? An HRV chart by age and sex, and how to read your own number
There's no single good HRV number — it depends on your age, sex, and above all your own baseline. Rough RMSSD ranges by age, why comparing to others is meaningless, and how to actually tell if your HRV is healthy: your baseline and your trend.
August 11, 2026
Why is my HRV so low? What a low heart rate variability actually means
A low HRV usually means your body is under stress or not recovering well — from poor sleep, alcohol, hard training, illness, or stress. What it means, the common causes, a normal dip vs a chronic low, and when it's worth checking.
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