Usable hours is a way of explaining how fatigue affects your ability to do things. We all have the same number of hours in a day but for someone with fatigue, they only have a limited number in which they can complete tasks.

How does that work?

It breaks down like this, a healthy person has 24 hours in a day but some of those are used up sleeping, leaving around 10–15 hours every day for doing tasks, working, socialising and just generally having a life. That healthy person can choose how they spend those hours and normally (and within reason) expect to accomplish everything they wanted to in that time.

For someone with fatigue, it goes a little differently. A LOT of those useable hours are often spent on recovering from tasks a healthy person probably doesn’t think twice about completing. Think about when you get up in the morning, without even consciously realising it you probably plan how best to get through your day, factoring in lots of rest time and breaks in the hope you can manage your fatigue and be as productive as possible. This is something a healthy person doesn’t have to do, they don’t need to ‘time budget’ as they have so many more usable hours in a day – they just get up and go!

An everyday example

It’s important that healthy people understand that it’s not just big or difficult jobs that are exhausting when you have chronic fatigue, even seemingly small tasks take planning. For example, a healthy person can take a shower and it will take 15 minutes but a chronically ill person could take 15 minutes and then need 2 hours to recover, and this can happen for every single daily task. So, what was 10–15 usable hours can become only 6, 4 or even 2 and on top of that you can never tell how much resting is needed for each task as there is no formula for figuring it out in advance: every day can be different. One day that 15-minute shower means you need 2 hours’ rest and the next you could spend the whole day recovering.

Useful analogies

This is where spoon theory comes in as it’s a way of measuring how much a task depletes your energy levels. I personally find spoon theory isn’t so relatable for everyone so tend to lean towards using the battery analogy as everyone understands how batteries work (and how annoying a malfunctioning battery is!) but honestly it’s just a personal choice: if you find an explanation that works for you stick with it and hopefully it’ll make it easier for you to get support from those around you on days when your usable hours are limited.

Living with variable usable hours

Whichever way you explain it, usable hours helps to describe the difference that fatigue makes to your life. There will be better days and worse days, but remembering that your usable hours are something to be respected can stop you pushing yourself too hard and ultimately making your fatigue worse.