I found out that I had a bilateral Pulmonary Embolism (PE) in March this year. It's possible for a PE to be fatal, so I had a near miss.

A PE is where blood clots make their way into your lungs blocking arteries. And that prevents your lungs from working as they should.

The blood clots in both my lungs were caused by cancer. I didn't know I had cancer at the time.

The first I knew of the PE was: my running went from going well to wheezing and coughing after only a few yards.

I had no idea what was going on. I’d start to run and my breathing felt like I’d been running an interval session.

At that point I assumed I’d caught a virus. So, I cut back the mileage and tried to moderate the intensity of each run.

By the end of that week, I had to walk. Running wasn’t an option - I’d get breathless straight away.

I rested over the weekend and went for a run on the following Monday morning.

It was a disaster. I only managed about 300 yards and I was gasping for air.

A trip to my GP led to a visit to the MDU department at our local hospital. I ended up staying in for four days.

Here’s how the NHS define a PE:

A pulmonary embolism is a blocked blood vessel in your lungs. It can be life-threatening if not treated quickly.

A PE can be fatal. Let’s be clear about that. Blood not making it around your lungs is never going to be a good day out.

Here’s the thing: the consultant that diagnosed me told me that what saved me was my physical fitness.

I’m fit because of running. Ergo, it saved my life - or saved me from being seriously ill.

The consultant said that restricted blood flow around my lungs was a major issue. But the other systems around my body were able to compensate. And that was because I'd looked after myself.

Enter cancer

The fact I also had bladder cancer wasn't diagnosed until a couple of months later. Cancer causes your blood to get sticky and therefore increase the risk of bloof clots forming.

I've had surgery to remove the tumours from my bladder - physical fitness helped me to recover from that too.

Do some cardio

My experience means I’ll offer a piece of advice:

What you choose to keep fit is up to you, but make sure it involves cardio...

Going to the gym and pumping iron will make you big and strong. But it’s putting your cardiovascular system under pressure that does the real stuff.

We all need to work our hearts and lungs over a sustained period of time. And on a regular basis.

That way, you won’t only look physically fit, you’ll also be fit. That’s fit on the inside - where it counts.

It doesn’t have to be running

I know that people don’t enjoy running. In which case, go cycling, swimming or even fast walking.

Yep, even intense walking can give your heart and lungs the right kind of workout.

The main thing is: work your heart and lungs. Because you never know, it might save your life one day.