Blog

Recovery science & insights

Learn how HRV, sleep, and activity shape your daily energy — and how to use that knowledge to perform and recover better.

hrvscience

What is HRV and why your morning number matters

Heart Rate Variability is the most sensitive window into your nervous system. Here's what it means, how it changes daily, and what to actually do with it.
trainingrecovery

How to Tell If You're Overtraining (And What to Do About It)

Your body sends clear signals before overtraining becomes a real problem. Here's how to read them—and how Capacity makes it hard to miss.
sciencescoring

How we calculate your Battery Score

A transparent look at the formula behind Capacity's daily score — Sleep (32 pts), HRV (45 pts), and Strain (23 pts).
recoverytraining

The 3-color system: Green, Yellow, Red

Your Battery Score maps to three colors. Here's what each one means and — more importantly — what you should actually do about it.
trainingstrain

Why 10,000 steps is not the full story

Steps are a good proxy for activity — but they miss an entire category of effort. Here's why Capacity now uses active calories to score your training more accurately.
sleepscience

Sleep stages and recovery: why deep sleep matters more than hours

Eight hours in bed doesn't guarantee good recovery. What happens inside those hours — and which stages matter most — makes all the difference.
wearablesgear

The Best Wearables for Recovery Tracking in 2026

Not all wearables are created equal when it comes to recovery data. Here's what actually matters, and which devices work best with Capacity.
recoverypatterns

Why Your Sunday Score Is Probably Your Best of the Week

There's a consistent pattern in Capacity data: most people peak on weekends. Understanding why helps you train smarter all week long.
hrvrecovery

How to improve your HRV in 30 days

HRV is one of the few health metrics you can meaningfully move in a month. Here are the 5 changes with the most evidence behind them — and what to actually expect.
trainingpro

Training Readiness: what it is and why it changes everything

Your battery score tells you how recovered you are. Training Readiness tells you something different — whether your body can actually absorb hard training today. Here's how it works.