A glance at Claudia Hammond’s The Art of Rest – and a skim of her chapter headings – might fool you into thinking that rest is a simple subject. There is something charming about a book that includes a chapter entitled A Nice Hot Bath (I hoped it might be followed by A Nice Cup of Tea) and I supposed that Hammond, a presenter of Radio 4’s All in the Mind, was about to offer us a cosy self-help book.

But The Art of Rest reveals that rest is not simple. This fascinating, entertaining and lucidly written book should be read by anyone ready to confess that rest is not their forte. We start to see that the subject is complicated partly because most of us are no good at resting. We are restless about rest. We feel guilty about it. We live in a culture obsessed with being busy – and this boasting about being busy is, Hammond argues, caught up with status. She summons Socrates to her side to warn us: “Beware the barrenness of a busy life.”

There is a survey behind this book – the Rest Test, led by researchers from Durham University. It involved more than 18,000 people in 134 countries, who were asked to list what they found most restful. Most felt they were not getting enough rest. The book is organised around their top 10 in reverse order: mindfulness, watching TV, daydreaming, having a bath, taking a walk, doing nothing much, listening to music, being on your own, spending time in nature. Most surprising was that at No 1 was... reading.

And it was while reading The Art of Rest that, by chance, I also dipped into Charlie Mackesy’s new picture book for adults The Boy, the Mole, the Fox and the Horse (a more restful book, illuminated by the consolation of low expectations, could scarcely be imagined). At one point, the mole asks: “Is your glass half empty or half full?” The boy replies: “I think I’m grateful to have a glass.”

It threw light on Hammond’s book: it occurred to me that what makes it hard for most people to stop and rest is the fear of experiencing what it would be like for the glass to be entirely empty.

Hammond reveals that taking a walk and having a bath are popular ways of resting because we are doing something – there is no guilt attached. But the opening chapter about mindfulness is more ambiguous. Meditation could be said to be doing something too – perhaps. But as a good scientist, Hammond takes nothing for granted. She points out that mindfulness is not a panacea.

My own view is that, for some people – especially those who have been traumatised – being alone with their breath, all thinking suspended, could feel like a near-death experience. The art of doing nothing is hard to master. And this is especially true in an age of interruption and with phones that make us feel “forever on call”. Hammond points out that for most of us (no matter where we live) it is “hard to switch off from work, even when we’re not actually working”. She hints at the potential tyranny of the fitness app: “This is the age of the quantified self where people are using technology to track everything…”

One of her most gripping chapters is about nature. Scientists have found it hard to pin down what it is about nature that restores us. I was reminded of how whenever I take the dog out on to Hampstead Heath after having driven through London’s rush hour traffic, I feel a lightening as soon as I step within sight of trees, a physical release – as if I had been carrying something heavy I could now put down (and I don’t mean the dog). Hammond acknowledges and explores this physical response – although more research on the subject is needed.

She also interviews the naturalist Richard Mabey (whose Nature Cure described the way that nature helped him out of depression). Having observed minute changes in a salt marsh, he tells Hammond: “That sense of change and recovery from change bedded itself quite deeply in my psyche.”

Reading this makes one wonder to what extent nature is in the eye of the beholder (after all, not everyone would see the marsh with Mabey’s keen eye).

Nature is open to varied interpretation and studies bring surprising findings: “managed” nature is found to be more restorative than wild nature (Romantic poets will be turning in their graves). And it is said that the more repetition there is in a landscape, the more we enjoy looking at it. Is that true? At least we can agree that we can get lost in a walk – as well as on one. Hammond quotes Rousseau: “My mind only works with my legs.”

Hammond’s goal is for readers to find “a fresh way of thinking about how they use their time” and we are invited to write our own prescriptions for rest. She encourages us with the thought that relaxing helps us “make better decisions, lowers our risk of depression, boosts our memories and means we catch fewer colds”.

Apparently, 1.6bn books were sold in the UK in 2018. If we accept that reading is the most restful activity (I had not come across “bibliotherapy” before), The Art of Rest ought to be equivalent to a scientific siesta. The only trouble is that this outstanding book is far too stimulating to be restful.

• The Art of Rest: How to Find Respite in the Modern Age by Claudia Hammond is published by Canongate (£16.99). To order a copy go to guardianbookshop.com or call 020-3176 3837. Free UK p&p over £15, online orders only. Phone orders min p&p of £1.99