Fatigue

Most people with cancer will experience cancer-related fatigue at some point during their cancer journey.

Fatigue is one of the most common side effects of cancer and it can appear:

as a symptom of cancer before you receive your diagnosis
as a side effect of treatments such as chemotherapy, radiotherapy, and immunotherapy
in the days and weeks following surgery.

People with cancer describe fatigue as feeling tired, weak, worn-out, heavy, slow, or that they have no energy or get-up-and-go.

It is very different to the normal feeling of tiredness that we all experience from time to time after a busy day or lots of activity. While normal tiredness is relieved by sleep and rest, cancer-related fatigue is not.

Quick facts:

Fatigue is the most common side effect of cancer treatment
Cancer fatigue is different from normal tiredness that people who do not have cancer feel
Fatigue can decrease your quality of life

Causes of fatigue

There are many different causes of cancer-related fatigue, which may include:

the cancer itself
side-effects of medications or treatments
worrying thoughts
pain
stress
uncertainty
surgery
eating difficulties
anaemia (low blood count)
reduced activity levels

Energy Levels

A useful way to think about how your fatigue affects your energy levels is to imagine a battery. Before you were affected by fatigue, you had a large battery that would drain gradually over the course of the day as you went about your activities.

With fatigue, your battery is smaller so it takes less effort for it to drain. This means you need to recharge your battery more often.

However, simply resting for long periods of time or doing very little activity won’t help. Just like a car that has been left parked on the driveway for a long time, the battery will eventually go flat if it isn’t used. Similarly, your body needs to keep moving in order to stay charged.

Therefore, it is important to remain physically active to help manage and reduce your fatigue.

Mental, physical and emotional energy

Fatigue doesn’t only affect physical activities such as walking, climbing the stairs or doing housework. For many people, there are cognitive effects as well. These can include:

reduced concentration
memory problems
difficulty finding words
difficulty thinking clearly
feeling emotionally drained

Sometimes you may have a physically restful day yet still feel tired. This can be because, even if you haven’t done anything physical, you’ve been using mental or emotional energy which can leave you drained.

Physical, mental, and emotional activities all require effort. This means that a mental activity such as completing a crossword can leave you as drained as an emotional activity such as worrying, or a physical activity such as walking.

So, it’s a good idea to alternate demanding activities with easier ones. It’s OK to take a break and come back to an activity, whether it is physical, mental or emotional. This can help you to keep your energy levels charged.

Managing your fatigue

There are lots of things that you can do to manage your fatigue and energy levels. When trying to manage fatigue it is useful to think about how it impacts your daily life and the things that you want or need to do.

Cycle of activity

The Cycle of Activity can help you to understand why physical activity is beneficial in managing your fatigue. Take a look at the following diagrams and think about how they relate to your fatigue.

When you avoid activity, your muscles get weaker. This can make it harder to do things, which then increases your fatigue. This is known as the vicious cycle of inactivity.

You can manage your fatigue by pacing yourself, planning your day and prioritising your daily activities. This can break the vicious cycle and create a positive cycle of activity.

More information

The following links provide more information and resources to help you understand and manage your fatigue: