Energy: treat the body as the engine

Protect sleep, movement, food, and quiet, because attention runs on physical energy.

Why it works

Focus is a physiological capacity, not pure willpower: it depends on sleep, blood sugar, movement, and recovery. When energy is low, attention degrades regardless of intention, so managing the body’s inputs is upstream of managing focus — you can’t will concentration out of a depleted system.

How to do it

1. Prioritize consistent, sufficient sleep as the foundation.
2. Add daily movement, even brief, to lift energy and mood.
3. Build in real breaks and quiet, treating recovery as productive.

Evidence

Strongly supported in aggregate: sleep deprivation reliably impairs attention and executive function, and exercise has well-documented acute and chronic cognitive and mood benefits. (rct)

The general links are robust; the specific bundle of "Energy tactics" in the book is a practical synthesis, not a tested package.

Sources

• Lim & Dinges (2010), meta-analysis of sleep deprivation effects on cognition, Psychological Bulletin

Common mistake

Trying to fix focus problems with more productivity tactics while chronically under-slept, when the real bottleneck is physical energy.