There are some things in life that it is deemed socially unacceptable for an adult to continue to do once they have left childhood behind. Pick their nose in public is one. As is staring idly at strangers on public transport.

But there are some things that mystify me. And the sad thing is that they’re stuck in my mindset too, and I often feel myself trying desperately to justify my activity.

One of these things is the fact that in our garden we have a trampoline. It is a lot of fun to bounce on it. But at 22 years old, I feel a bit odd doing it. I bounce up, and can see over the garden wall and often to people in the street or in other gardens. So it’s not a particularly private affair. People can see that I’m on the trampoline.

It doesn’t bother me to a certain extent, but I do wonder what they must be thinking. Why is it not appropriate for an adult to go on a trampoline in public? At what age does this sudden cut-off occur, when heads will shake, brows will furrow and questions be asked about the mental faculties of such a, clearly, errant adult?

And why? Why is the big question. Why would it be “a bit weird” and leave people somewhat uncomfortable if they saw, say, a 45 year old man bouncing on a trampoline? Or even a woman for that matter.

Don’t deny it. Because I can’t deny it either. If I saw that I couldn’t help but feel a little niggle in the back of my mind saying “There must be something wrong with him/her”.

That really aggravates me. Because I thought I was more open minded than that. But there is just something not quite right about the thought. And yet, if a private individual wishes to have some fun that has no impact on anyone else, what right do we have to sit in judgement?

Going on the trampoline is a lot of fun and is good exercise. But it’s seen as a very childlike thing to do. And it got me thinking just how many taboos we have in our society that stop adults enjoying themselves.

It’s one of those collective action problems that I did so much about in the last year of university. None of us is prepared to break the mould, because we’re not confident enough to believe that if we do it others will follow. Somehow we’d all need to break it together. Otherwise, everyone will wait for everyone else to act, the result being no one acts at all.

Or maybe I just need to learn to grow up and accept that I’m an adult now.

But there’s no way I’ll ever accept that.