Researchers have suggested that chronic pain sufferers could be kept physically active by improving the quality of their sleep.

The study found that sleep was a worthy target for treating chronic pain and not only as an answer to pain-related insomnia.

Study lead-author Dr Nicole Tang said engaging in physical activity is a key treatment process in pain management. Very often, clinicians would prescribe exercise classes, physiotherapy, walking and cycling programmes as part of the treatment, but who would like to engage in these activities when they feel like a zombie?

Dr Tang and study co-author Dr Adam Sanborn examined the day-to-day association between night-time sleep and daytime physical activity in chronic pain patients.

Tang said that many of the patients struggled to stay physically active after the onset of pain and we found that chronic pain patients spontaneously engaged in more physical activity following a better night of sleep.

She said that the research points to sleep as not only an answer to pain-related insomnia but also as a novel method to keep sufferers physically active, opening a new avenue for improving the quality of life of chronic pain sufferers .

The study saw chronic pain patients wear an accelerometer that measured motor activity to monitor their physical activity round the clock for a week in their usual sleeping and living environment. Additionally, they gave ratings of their sleep quality, pain intensity and mood using a mobile electronic diary every morning on waking.

Researchers used the time-specific data to determine, for individual patients, whether the quality of their sleep had an impact on how physically active they were the following day.

Multilevel models for each of the predictors were fit, and the only reliable predictor of physical activity was sleep quality.

A comparison between multilevel models demonstrated that sleep was a better predictor of physical activity than morning ratings of pain intensity or mood.

The study has been published in journal PLOS ONE.