Manage energy, not time

Treat your capacity, not your calendar, as the scarce resource to protect.

Why it works

Hours are fixed and uniform, but the energy you bring to them is not — the same task at low capacity costs far more and yields less. Managing energy means matching demanding work to your high-capacity windows and deliberately renewing capacity, rather than packing the calendar and hoping for the best.

How to do it

1. Notice when your energy is naturally highest and reserve that window for your most important work.
2. Stop measuring a day purely by hours worked; measure by energy spent and renewed.
3. Protect renewal as a real input, not a reward you earn after the work.

Evidence

The "energy management" framing is a practitioner model. Its premise — that performance fluctuates with physiological and psychological state rather than being constant across hours — is consistent with research on fatigue, attention, and ultradian variation. (mechanistic)

The overarching model is a framework, not a tested intervention; treat it as an organizing lens whose components carry the real evidence.

Sources

• Loehr & Schwartz (2003), The Power of Full Engagement

Common mistake

Optimizing the calendar (more meetings, tighter blocks) while ignoring whether you have the energy to do any of it well.