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The one where friends help to keep each other active



Friends, the 90s TV Sitcom, is a firm favourite for today’s teens. The ups and downs of the six Friends living in New York covered many topics and some episodes showed the how friends can support - or indeed undermine - each other’s physical activity (e.g.‘The One Where Phoebe Runs’).

The influence of friends (and I’m referring to friendships and peer groups rather than the sitcom) amongst young people is something our team of researchers has been trying to harness to increase adolescent girls’ physical activity.

It’s easy to see that younger children such as toddlers are always on the move, but teenagers can be less active and  often spend more time sedentary than youngsters. The decline in physical activity is almost universal as children grow up, but for girls the decline in activity is much greater. From age five onwards, most girls are less physically active than boys. By their mid-teens very few girls are active enough to get the physical and mental health benefits of being regularly active.

Getting anyone more active is hard, but for teenage girls, what their friends think and do is crucial. Like the Friends characters, when it comes to being active, peer groups can create unwritten rules that determine how physically active they are, be active with each other, decide what is cool, or challenge what it means to be a girl or other hurdles which might stop them from being physically active.  There is much power in one’s peer group.

Influencing exercise through peer support

We have tried to capture this peer-power in the PLAN-A project (Peer-Led physical Activity iNtervention for Adolescent girls). PLAN-A is a school-based intervention where all girls in a year group nominate their ‘influential’ peers - girls they trust and respect, who are good leaders and good listeners. The girls voted as most influential (about 15% of the year group) are asked to be peer supporters and are given two days training, away from school by external trainers. Training blends learning about physical activity with the practical skills to support others such as empathy, confidence, good listening and judgement. Peer supporters are then tasked with creating new norms around physical activity amongst their peers – not by starting new exercise groups or putting posters up – but by talking positively about being active, making suggestions, identifying opportunities to be active in daily life and challenging stereotypes. Peer supporters receive another day of training about five weeks after the initial session to maintain momentum.

From 2015-2017 we received funding from NIHR’s Public Health Research (PHR) Programme, and we worked with six secondary schools and over 400 Year 8 girls in the South West to see if PLAN-A had potential; Would schools let us work with them? Would the girls like the training? Would they convince their friends to be more active? We found that PLAN-A could be delivered to the whole year. Pupils, parents and teachers liked it. Crucially it showed real promise for stemming the decline in physical activity in teenage girls and the cost was worth it for the possible returns in health.

The next steps in boosting teenage girls’ physical activity

Based on the potential of PLAN-A, in 2018 our team received further PHR funding to conduct a larger trial as well as funding from Sport England who help pay for the peer supporter training. This will help give us a more definitive answer as to whether PLAN-A is effective at keeping girls active and is affordable. The study is currently underway in 20 schools involving over 1,000 adolescent girls.

Time will tell whether PLAN-A can successfully harness the power of friends and contribute to more active lifestyles amongst adolescent girls. Time will also tell how long Friends remains the favourite TV show amongst young people! More information on the PLAN-A study is available on the NIHR Journals Library and the project website here.

The views and opinions expressed in this blog are those of the authors and do not necessarily reflect those of the NIHR, NHS or the Department of Health and Social Care.


The views and opinions expressed in this blog are those of the authors and do not necessarily reflect those of the NIHR or the Department of Health and Social Care.