What's a Good HRV for My Age? Complete HRV Chart and Guide

You've seen your HRV number on your Apple Watch or fitness tracker, but what does it actually mean? Is 45ms good or bad? The answer depends heavily on your age, as HRV naturally declines throughout life. This guide breaks down what constitutes healthy HRV at every age, how to interpret your score, and what you can do to improve it.

What is HRV and why does it matter?

Heart rate variability measures the variation in time between consecutive heartbeats, expressed in milliseconds. Higher HRV generally indicates better cardiovascular health, lower stress, and improved recovery capacity. Research consistently links higher HRV to longevity and lower all-cause mortality risk.

Apple Watch measures HRV using the SDNN method (standard deviation of normal-to-normal intervals), typically calculated during sleep or rest periods. My Bio Age uses this data as a key contributor to your biological age calculation.

Average HRV by age (SDNN, milliseconds)

These ranges represent typical population averages. Individual variation is significant— genetics, fitness level, and lifestyle all play roles.

Note: These are general guidelines. Very fit individuals often exceed "above average" ranges for their age, while those with chronic stress or health conditions may fall below.

Why HRV declines with age

HRV naturally decreases as we age due to several factors:

• Reduced parasympathetic (vagal) tone
• Decreased elasticity of blood vessels
• Accumulated oxidative stress and inflammation
• Changes in autonomic nervous system function

However, the rate of decline varies significantly based on lifestyle. Fit, healthy individuals can maintain HRV levels of people decades younger, while sedentary or chronically stressed individuals may show accelerated decline.

Your personal baseline matters more than averages

While population averages provide context, your personal trend is more important than any single number. Someone with a baseline HRV of 40ms should pay attention if it drops to 30ms—that's a significant change regardless of whether 40ms is "average."

My Bio Age tracks your HRV trend over 14 weeks, comparing today's reading to your personal baseline. The app alerts you to significant deviations and includes HRV in your biological age calculation relative to both personal history and age-appropriate norms.

What affects your HRV day-to-day

Short-term HRV fluctuations are normal and reflect:

• Sleep quality — Poor sleep immediately suppresses HRV
• Alcohol — Even moderate drinking reduces HRV for 2-3 days
• Exercise — Intense workouts temporarily lower HRV; recovery raises it
• Stress — Psychological stress directly impacts autonomic balance
• Illness — Fighting infection suppresses HRV (often before symptoms)
• Hydration — Dehydration strains cardiovascular system
• Caffeine — Can temporarily reduce HRV in some individuals

How to improve your HRV

Improving HRV requires consistent lifestyle habits rather than quick fixes:

• Prioritize sleep — 7-9 hours, consistent timing
• Aerobic exercise — Zone 2 training builds aerobic base
• Stress management — Meditation, breathwork, nature exposure
• Limit alcohol — Reduce or eliminate, especially before bed
• Cold exposure — Cold showers stimulate vagal tone
• Slow breathing — 5-6 breaths per minute activates parasympathetic
• Balance training load — Avoid overtraining

Track HRV in context with My Bio Age

A single HRV number tells you little. Context matters: How does it compare to your baseline? To age-appropriate norms? How does it interact with your other health metrics?

My Bio Age provides this context automatically. Your HRV contributes to your biological age alongside VO₂max, sleep, recovery capacity, and other signals. The on-device AI Coach can answer questions like "Why is my HRV low today?" by analyzing correlations with sleep, activity, and recovery patterns.

Download My Bio Age to understand your HRV in the context of your overall health—and watch it improve as you optimize your lifestyle for longevity.