This week Public Health England told us that along with doing aerobic exercise we should be doing muscle and bone strengthening and balance activities. It recommends ball games, racket sports, dancing, Nordic walking and various forms of resistance training. The benefits of physical activity include reduced risks from certain cancers and heart disease, better mobility, better sleep and mental health and, as we get older, the prevention of falls.

But will this make the slightest bit of difference? In short, no it won’t. Putting information into the public domain as a strategy for getting people to change their behaviour is simply not effective.

Since the discovery was made about the links between smoking and lung cancer more than 60 years ago, there has been a huge investment by government bodies in providing information in the hope that people will change their behaviour. This takes many forms. Some is soft information – facts about risks, dangers and benefits. Sometimes it has taken the form of scary warnings and frightening imagery. But at best, the effects of such information are marginal.

The reasons for this lie in our basic psychological makeup. Our thinking and behaviour is governed by two systems – reflective and automatic. The reflective one requires effort – we have to think things through and weigh up costs and benefits. Information like that from Public Health England will only change things if it is processed by our reflective system. We have to hear what is being said, understand it, work out what to do, and then proceed to do it. Clearly, some of our behaviour arises as a consequence of our reflections on information.

But a great deal more of it is governed by our automatic responses to the circumstances we find ourselves in. We respond to things in our environment; to what’s on offer in the cafeteria – are the chips and sugary options easier to find than the salad? In your local high street, how many fast-food outlets are there selling cheap, nutritionally poor, calorie-rich foods, and how many shops sell green vegetables? All humans are evolutionarily hardwired to find food with as little effort as possible. Not surprisingly, with food choices and most other health behaviours, such as alcohol consumption and undertaking physical activity, we take the easy, automatic option.

The biggest public health success of the last 50 years has been the reduction of levels of smoking. When the NHS was set up 70 years ago, most of the adult population were smokers. Figures issued this week show that about 15% of adults smoke. Has this been achieved by issuing information and hoping for the best? No. Information and health education have certainly played a role, but success has been achieved through an integrated strategy involving price, taxation, control of advertising, availability and legislation. Today, cigarettes are all but invisible in the retail environment, and the places in public where people can smoke are strictly limited.

The evidence that Public Health England draws upon about strength and balance has been compiled by several of the UK’s leading physical activity scientists. There is nothing wrong with the evidence. But evidence on its own doesn’t change things.

Getting the population more active is an absolute priority. Physical activity does reduce risk for a range of serious illnesses, and the benefits last well into old age. It is also highly cost-effective. To get the population active requires a great deal more than drip-feeding them information and evidence. It requires increasing people’s opportunities to be able to be physically active. This does not mean more gyms, but it does mean providing more opportunities to walk and cycle safely. It requires helping people to develop motivation and acquire the skills to do the activities. It is about opportunities to be active. Have you ever wondered why the moment you leave a small country village on foot, the pavement disappears after about 30 metres? Why are we unable to walk safely on our country roads? This is an infrastructural failure, and only by fixing things such as this will change come about.

• Mike Kelly is senior visiting fellow in the Department of Public Health and Primary Care at the Institute of Public Health, University of Cambridge