I was 12 years old, dressed in an awful polyester tracksuit, and waiting to start my first ever wheelchair race. It was sports day, which was a big deal at my school. Lessons were suspended and replaced with swimming, hockey and sprinting. Kids filled the crowds, giggling, chatting and cheering. Everyone wanted to win something. But how did I feel about my big chance? A little ambivalent, to be honest.

I had been using a wheelchair for five years, after my spine began to degenerate from a condition called spina bifida. And while I did grow up in a sporty household, I didn’t picture any kind of future for myself as an athlete. I swam. I rode horses. I played tennis. My parents felt physical activity was massively important for me to be able to have an independent life – I needed to be strong enough to climb up a flight of stairs by myself, they insisted, and they were right.

But wheelchair racing? Going round in circles? What on earth would anyone want to do that for? I wondered. But there I was. The sun was shining. And suddenly, a teacher blew the whistle. People shouted encouragingly. I remember that moment so clearly: nerves flooding through me and then rushing forward, speeding, racing. There were 110 metres of concrete track ahead of me and I was flying. Oh wow, I thought, this is brilliant. At that moment I became obsessed.

I went on to win the junior national racer title at 15. In total, I’ve won 16 Paralympic medals (11 gold, four silver and a bronze) and 13 World Championship medals (six gold, five silver and two bronze) in my 23-year career. That feeling of exhilaration during a race never leaves you. Despite hanging up my racing wheels over a decade ago, I still get a buzz when we enter an Olympic and Paralympic year.

The 2020 Games in Tokyo feel particularly special: there have been an unprecedented number of ticket requests for the Paralympic Games (over 3 million, compared to the 2 million sold for Rio) and the number of female athletes is almost equal to men for the first time. The Paralympics defined my life, but they also reach into homes across the nation, redefining public perception of what’s possible. And against the backdrop of modern feminism, which has come a long way since the last Games, we need to champion what women can do.

Yet, we have a problem with physical activity in the UK. Sport England’s Active Lives survey shows 26% of women are inactive. Things are improving, albeit slowly: it’s worth noting that there were 142,000 fewer inactive women in 2018/19 than in the previous year, and weights and interval training are showing a significant increase in popularity. But we can do better.

The reasons behind our lesser involvement in sport are complex. I believe it starts from the moment we’re born. Boys are encouraged to kick a ball, while girls, despite progress such as the Women’s Super League becoming fully professional for the first time last year, are still seen to cheer from the sidelines. Further research from Sport England shows that girls are less likely to take part in team sports, despite saying they enjoy being active. These early experiences form how we relate to physical activity as an adult. We worry about being judged and how we’ll look if we lose.

But this attitude is hurting us: 40% of British women aren’t doing enough exercise to stay healthy, according to the World Health Organisation, so how do we address it? For me, it’s about taking the self-consciousness out of sport. Take the recent This Girl Can campaign, which showed women sweating, bleeding and smiling with elation at what they’ve achieved. These were real women being active. Not Olympians or Paralympians, whose job it is to train 12 to 15 times a week and look incredibly toned because of it. They’re a tiny percentage of reality.

Perhaps we need to redefine our idea of role models; they’re not always elite athletes whose success might seem too distant or unachievable. Sometimes it’s our friend who just smashed her first 10k, or our Zumba teacher who is enthusiastic, encouraging and real.

Today, I try to be as active as I can. I walk to meetings and get out in the fresh air. It’s necessary for my mental health: if I’m active, I’m more able to work (I’m a peer in the House of Lords and the chair of Ukactive) and generally happier.

When I think back to 12-year-old me, overwhelmed by the racing track in front of her, I want to tell her how good it feels to speed across it. You owe yourself the same.

Baroness Grey-Thompson is a Welsh peer and former wheelchair racer. She won 11 Paralympic golds and broke more than 30 world records. Today, she advocates for disability rights – and plays Abba songs on her piano when she wants to relax.