On a few occasions of the last weeks I have felt a twinge of guilt about the mountain marathon I was planning to run this weekend. Kind friends and supporters had enabled me to raise nearly £2.5k for the RSA Great Room appeal and all I was doing was a run - albeit a tough run - in a beautiful part of the world.
This morning, with feet covering in blisters, aching ankles, thighs so tense I need help to stand up from a sitting position, skin covered in small itchy red midge bites; I feel I really earned that money.
I re-learnt quite a few lessons this weekend. For a start, do your homework. Rather than the LAMM being a long run up hills - which it is only for the very best competitors - for someone like me it is a kind of merciless hiking.
I got the feeling that things were going to be tough when we turned up early Saturday morning to be greeted by a science fiction vision of tens of stewards and hundreds of competitors all wearing nets over the heads to protect them from midges. The sense that this was an event for the totally dedicated was confirmed when we were bussed to the start to be immediately confronted with a 400 metre climb over rough ground up a steep hill. Having struggled to the top, we prayed that for some reason the organisers had put all the tough stuff at the beginning - after all we were running in the easiest class in the event - but no, after an uncomfortable descent, the next hill was a killer; 700 metres of ascent all steep, all on difficult terrain.
I was badly unprepared but Philip, my partner for the event, had his training schedule in the weeks leading up to the event interrupted by a work deadline. By a third of the way up hill two he was in deep trouble. Just about the best way to do hills like this is simply to keep going, letting your heart rate build up and drive you on. So stopping every ten minutes to let my friend lean heavily on his stick looking like death warmed up made a very tough task even tougher.
Having looked at previous year's times, the four of us who travelled to Ben Cuechan together were hoping to complete the first day's 19km in close to five hours. The other younger pairing managed a creditable time just under six hours, but Philip and I eventually crawled into the midway camp 9 hours 20 minutes after setting off.
After about two hours on Saturday Philip was clear he wasn't going to do the course on Sunday. I was sorely tempted to join him on the long but flat direct walk back to base, but this is where the sponsorship had its effect: how could I let down the people who had backed me? So, despite a virtually sleepless night in which multiple sources of pain vied with the claustrophobia of a tiny two man tent and the knowledge that it was impossible to get out without being swarmed by midges, I found a new partner (Royal Marine, John, whose first day companion - an experienced long distance runner from Pakistan - had also succumbed to cramps, blisters and exhaustion) and set off with the other two friends.
Day two was a little easier, although still involving ascending a substantial mountain by another steep, rough route. But the state of my feet meant that every step was painful, with coming downhill - if anything - even more daunting than going up. But eventually we made it and in a decent enough time of 6 hours 20 minutes. It would have been faster had we not spent 45 minutes searching for the penultimate contact point (I haven't mentioned the orienteering aspect of the event because - to be frank - I relied entirely on my partners and following other runners to identify where to run next).
I would love to report a sense of exhilaration and wellbeing at the end but so shattered were we that even the planned beer and curry celebration in Glasgow turned into damp squib as we were all overcome by weariness and me by the obligatory headache which follows extreme exertion.
Although quite a few people joined Philip on the flat walk home, I am overwhelmed by admiration for the other competitors in the race. Take a bow the couple with a combined age of 112 who did the two routes in a total of less than ten hours and the father and partially sighted son team who sprinted down the treacherous hills connected by a piece of rope while somehow avoiding the hidden streams, bogs and sharp edged rocks.
Unlike me, the competitors seemed to take the tough course (and apparently it genuinely was a tough course for our category), the fiendishly placed contact points, the midges and other minor irritants, like the mystery of the always engaged cubicle two at the end of the far-from-fragrant Portaloo queue, in their long and bouncy stride.
However much I like a challenge, and even knowing if I ever did this again I would be a lot better prepared, I doubt very much I will be entering another mountain marathon. The event was set in the most amazing countryside but only very occasionally did I remember where I was and get a tiny wisp of pleasure from the view across the mountains or the clouds rolling down over the ridge we were traversing.
So thank you to the organisers for making such an event possible, thank you to the other participants who inspired me to keep going proving that for those who know what they are doing, these events can be fun, but most of all thank you to my sponsors.
As I looked up to the first of the two big climbs on day two, 17km to go, my legs as weak and stiff as cardboard and the six blister plasters I had carefully placed on my feet already floating around in my bog-filled shoes, it was to avoid admitting to you that I had failed that kept me going.
And, despite everything, I am really, really glad I did.