23 year-old Euan Ryan is a keen climber and adventure filmmaker at Finalcrux Films based in Glasgow. Unbeknown to many of his friends and followers, Euan suffers from the debilitating inflammatory bowel condition known as Crohn's Disease. The first week of December was Crohn's Awareness Week, and Euan wrote a blog about his diagnosis and outdoor life ever since. Euan has kindly allowed us to reproduce the blog below.

As I write this, I’m experiencing a painful, dull ache in my lower abdomen. It feels like there’s a pair of hands kneading my intestines into a fine dough - a rolling, rumbling sensation. Not a pleasant feeling. The kind of feeling that would make you think “Hmm, I should make a doctor’s appointment. Something’s not right in my tummy.”

The sensation I’m experiencing is actually the mucus membrane that lines my intestinal tract slowly being broken down and shedding from my bowel wall. An infection, you ask? A tropical parasite hell-bent on destroying my innards? The dreadful result of a night at the local curry house?

None of the above.

I wish it were one of those. Each one has a cure or will only last a few days at most before the body’s immune system deals with it and brings everything back to that sweet, sweet “once a day” equilibrium.

In essence, my immune system is confused and there’s nothing I can do about it.

I began to experience this all too familiar pain as a teenager, working my way through a tough high-school career. I was a climber and spent every waking moment at the local wall or outdoors working on my trad-climbing apprenticeship. A fit, active child, I loved nothing more than getting outside and exploring new places - rather unconventional for a post millennial youth. Let’s just say I wasn’t one of the “popular” kids at school and had to keep my head down to avoid trouble as best I could.

My teachers had started to notice my frequent and urgent need to use the bathroom. One minute I’d be happily doodling in the back of my jotter avoiding the lessons being taught, the next I would be writhing in pain as ghostly hands gave my intestines a good old fashioned Chinese burn.

I soon figured out a coping mechanism to help deal with the growing problem. I noticed that these cramps were usually within an hour or so of having eaten a meal. So, to avoid the need to use the bathroom at school, I would skip breakfast. By lunchtime, as you can imagine, I would be ravenous. However, if I allowed myself to eat lunch, the afternoon’s classes would be severely disrupted by the dreadful routine. So, I abstained and kept my fast through till home time.

Now, if you’ve ever managed to keep a fast for longer than 9 or 10 hours, you’ll know that towards the end, it actually gets easier. This is because your stomach shrinks and your desire for large quantities of food starts to diminish. Added to that the lack of sustenance and a full day of school, I was just about ready to go to bed as soon as I arrived home.

As you can imagine, this cycle of not eating much, if anything, started to take its toll on my body. I lost weight, grew weaker, lost muscle mass and became fatigued. Although, looking back, it’s obvious to see, these dangerous symptoms went by unnoticed not only by me, but my friends and my teachers and even my parents. It was such a gradual change that it really wasn’t apparent until it was all too late.

I eventually became too weak to walk to school and begged my mum for a lift in the car nearly every day. I had to stop climbing because I was just too tired and weak. My relatively small social life became non-existent. My GP couldn’t work out what was wrong with me. “A touch of IBS” he’d say. It took a referral to a specialist to finally get closer to some answers.

I was booked in for a colonoscopy. For anyone out there who is not familiar with this procedure, I‘ll explain it as simply as possible – the doctor pushes a miniature camera up inside you and takes a good look around the inner workings of your body’s sewage system. As a 16 year old boy, I wasn’t best pleased about this. It was one of the most violating and humiliating experiences of my life. But it was the key to unlocking some much needed answers.

“I’ve reviewed your colonoscopy results and it appears you have Crohn’s Disease. We will start you on a course of heavy-duty steroids and other medications immediately. You will need to stay in hospital until we can get this under control.”

My whole world started to spin off its axis. My parents were broken. Seeing me lying in a hospital bed put my sorry state into unbearable context. I was skeletal. The skin hanging off my bones. I was seriously ill, and I looked it. We all wondered how on earth we’d missed it for so long.

2 weeks.

A hospital ward full of the old and the sick. It had been my home for the past fortnight and now I was being set free. I had gained weight, the steroids had helped my body start to recover and I had medication that was helping to keep my immune system at bay.

Slowly, I was able to return to the things I love doing. Being outside, exploring, adventuring and, most of all, climbing. My muscle came back, my fitness was rebuilt and my ambitions soared.

Fast forward to today. This evening. As I write this, sat at my desk. I have forged a career in climbing and the outdoors. I am one of those extremely lucky few who can genuinely say they love doing what they do. I make films and take photographs of climbers and other adventurous folk. I get to explore and go on trips with like-minded people. And the best part? I can pay my mortgage with the proceeds.

And yet, as I write this, I feel the cramp and clutching of my intestinal tract. I feel my body going down this most self-destructive path. I’m experiencing what is known as a flare-up. My Crohn’s lies relatively dormant most of the time, but occasionally due to stress, anxiety, poor meal choices or sometimes for no identifiable reason at all, it rears its ugly head and reminds me what the word “chronic” really means. It’s not going away. Smart scientists and clever researchers toil day in and day out to try and come up with a cure, but right now, as it stands, it’s not going away. My flare-up may require a tweak to my medication, or it may simply require a bit of TLC and putting my feet up for a couple of days. It will pass, but it serves as a reminder of the horrors from my past.

As a climber, mountaineer and general all-round “outdoorsy” type, it’d be fair to say that I like keeping fit and healthy. There’s a very specific satisfaction to be gained from pushing your body into the “zone” (somewhere between general discomfort and full-body suffering). Ok, that satisfaction is, more often than not, only really felt once at home and in a hot shower, but it’s definitely there.

Most sporty people know where that sweet spot is. They know when they’ve pushed their body hard, but not totally rinsed themselves. Gains will be made, but injuries are avoided. I, however, have a small issue to contend with when it comes to finding that limit. You see, with my Crohn’s disease, my body can sway quite dramatically from “normal fitness” to “running on empty”. A full-on Scottish winter day out can leave anyone feeling pretty pooped, and I am no different. However, if my Crohn’s is going through an “active” period, a day out like that could have serious consequences not just for me but also for my climbing partners. This is where a certain degree of common sense can be applied. If I’m not well or am experiencing signs and symptoms of a flare-up, I just don’t risk it. Simple as that. My climbing partners understand.

Fatigue is a symptom that nearly every patient with an IBD (Inflammatory Bowel Disease) experiences. This can range from just feeling like an early night is in order to not being able to leave your bed for days on end. Luckily, and I put a lot of this down to my lifestyle, I never experience the extreme fatigue that so many IBD sufferers do. For me, the fatigue I experience after a big day out or a particularly gruelling training session is the kind of fatigue I’d imagine any normal person would experience. It’s just that I might take a couple more days to begin feeling 100% again. Crohn’s affects the way your body absorbs nutrients from your food and so recovery can be affected.

At the end of the day, with a chronic condition such as Cohn’s Disease, it all comes down to finding coping mechanisms. I cope with my condition with medication. I also cope through meal planning. I also cope through stress and anxiety management. I cope by being outdoors as much as possible. I cope by keeping myself busy and not letting it hold me back. I cope by knowing my exact distance to a public toilet with uncanny accuracy. I cope by the support afforded to me by my climbing partners, colleagues, friends and family.

Ask 75% of people who know me, and I bet they have never noticed. I plan to keep it that way.

It’s only a weakness if you let it make you weak. “Weakness” is subjective. After all, my condition doesn’t define me. I’m much more complex than that…

• For more information on Crohn's Disease, visit Crohn's and Colitis UK.