2015 has been the year of Taylor Swift. The young popstar has become a worldwide phenomenon, selling millions of records, selling out stadium tours, while also assembling the biggest crew of A-lister friends on the planet. Arguably, Taylor and her friends have grown into one of the most powerful friendship circles in the world.
Whatever you make of the spectacle, the emphasis Swift places on her girl friendships is resonating with young women. They epitomise that everything is always better when you're doing it with your nearest and dearest.
To dismiss girls' friendship groups as silly or trivial is a huge oversight for sport organisations. For teenage girls that lack self-confidence, having a solid group of friends is vital. Having people around them that you know and trust gives them both emotional and social support - especially when it comes to exercising.
Our own research which launched this week reveals that 63% of young women say they won't play sport or exercise unless a friend is going too. For over three-quarters of young women, the opportunity to catch up with friends is the number one reason they take part in any sport.
But it's not all about socialising - girls are also telling us that just being in the company of their friends has a big impact on their confidence levels when exercising. Over two thirds (67%) say they feel more comfortable exercising with their friends compared to exercising with people they don't know. Without their mates, they feel awkward, self-conscious as if everyone is looking at them.
The consensus seems to be that if their friends aren't there, girls are much less likely to take part in exercise.
So, why do this matter? Recent research by Sport England shows that women are much less likely to exercise or play sport than men and just half of young people take part in any sporting activity at all on a weekly basis.
It's always dangerous to make blanket assumptions based on gender, but there do seem to be some clear differences between boys and girls in terms of what motivates them to get (and stay) involved in sport. For young women, incorporating a social aspect into sport and exercise classes is one way we can encourage more girls to take part.
The girls we work with tell us they want to take part in activities which are informal and fun, whether that's a Zumba class, a casual football match once a week or multi-sport sessions where anything goes. Classes need to be relaxed so girls can dip in and out, creating a fun and relaxed atmosphere.
Taylor Swift has helped us celebrate the power of female friendships. Sports organisations can learn from Taylor and her friends by embracing the social side of sport too.
To help address this issue, we've launched a new series of guides looking at how to get more teenage girls physically active through understanding the role that friendships play in getting more young women involved in sport.