The majority of doctors in England are unfamiliar with recommended levels of physical activity, with fewer than two-thirds confident about discussing the topic with their patients, researchers have revealed.

Set out in July 2011 by the Chief Medical Office, national guidelines recommend that adults aged between 19 and 64 undertake 75 minutes of intense activity or 150 minutes of moderate physical activity a week.

But in 2015-16 more than a quarter of adults in England were deemed “inactive”, undertaking physical activity for less than half an hour a week.

Now a nationwide study has revealed that 80% of GPs in England say they are unfamiliar with the national guidelines, and more than one in seven doctors say they are not confident raising the issue of physical activity with their patients.

“Many people have described [physical activity] as the most cost-effective drug we have, yet we are not implementing it properly,” said Justin Varney, co-author of the research from Public Health England (PHE). “This is as appropriate as having a conversation about smoking,” he added.

Published in the British Journal of General Practice by Varney and colleagues at PHE, the study was based on an online questionnaire open to GPs in England for a 10-day period during March 2016. Quotas were put in place to guard against all responses coming from one region.

Participants were asked six multiple choice questions, ranging from whether they were familiar with the national guidelines on physical activity to selecting medical conditions around which they would discuss physical activity with a patient.

The results, based on answers from 1,013 doctors, reveal that only 20% were familiar with the national guidelines, with 30% admitting that they had never heard of them at all.

Doctors’ familiarity with questionnaires used to gauge patients’ activity levels was similarly hit-and-miss. More than a quarter of doctors were unaware of any such questionnaires, while 55% said they did not use such tools. More than half of doctors said they had not had any training about encouraging patients to undertake physical activity.

Only 78% of doctors said they would discuss and recommend physical activity to overweight patients, while just 26% said they would bring it up with patients living with dementia or cognitive decline.

“Being physically active is a separate conversation from losing weight,” said Varney. “Whatever your weight, if you are more active than someone who is of the same weight and inactive you will be healthier.”

The study also found that only 61% of GPs said they were either very or somewhat confident about raising the issue of physical activity with patients, with 16% saying they were somewhat or very unconfident in broaching the topic.

While Varney admits that nurses and other healthcare administrators were excluded, and that doctors with a keener interest in physical activity might have been more likely to respond to the survey, he said the sample included GPs across the country of different ages and seniority.

The authors say physical activity needs a greater emphasis during medical training, while more needs to be done to increase GPs’ awareness of training initiatives. Both are areas which PHE, Sport England and other partners have developed programmes to address, said Varney.

Alice Smith, professor of lifestyle medicine at the University of Leicester who was not involved in the study, welcomed the research but described the findings as disappointing and worrying.

“Physical activity is a fundamental element of a healthy lifestyle, and more and more research is showing that it is effective in the prevention and management of chronic disease,” she said. “It is vital that GPs at the forefront of healthcare are aware of this and know how to help their patients gain the wide-ranging benefits of an appropriately active lifestyle.”

Gavin Terry, the Alzheimer’s Society’s policy manager, added that tailored exercise advice can be extremely beneficial for people with dementia.

“It’s crucial that GPs are aware of the benefits of exercise for their patients and are aware of what is available locally to enable them to continue to take part in physical activity after a dementia diagnosis,” he said.

But Helen Stokes-Lampard, the chair of the Royal College of General Practitioners, said that while it is important that GPs are up to date on physical activity guidelines and the tools that accompany them, 10-minute patient consultations are too short and are “stifling” the use of such measures.

“Ultimately, we need the pledges in NHS England’s GP Forward View – including £2.4bn a year for general practice and an extra 5,000 full-time equivalent GPs by 2020 – to be delivered in full and as a matter of urgency so that GPs can spend longer with our patients and inspire them to make improvements to their lifestyle,” she said.”