Twenty years ago and when I knew no better, I used to run marathons. I'd finish one marathon and sign up for the next one, each time aspiring to run just that little bit faster.
It was only when I finished the Marathon des Sables and was wondering which fresh windmill to tilt at that I saw the light.
What men need is: New Stuff.
Many middle-aged men tend to throw themselves into ever-more crazy races and tests of physical endurance.
Problem is: they're just doing the same-old, same-old.
They never evolve.
The Ten Secret Ways to Happiness
1. Swim the Hellespont
This is the world's greatest, most iconic swim. If you're not a swimmer, or if you're terrified of deep water, it's a must.
Took me over a year of swimming lessons before I was even ready to attempt this two-miles Turkish strait from Europe to Asia.
I finally swam this great waterway on the third attempt - made it in with two minutes to spare. The feeling of euphoria lasted over a week.
2. Join a Choir
For well over three decades, I was terrified of singing in public.
Going on the principle that all fears must be confronted, I started up a choir with a dozen mates. We practised for months - and had one concert.
When it was all over, the relief cascaded over me.
3. Public speaking
First time I had to make a speech, I was shaking with nerves.
When I stood up on the podium, utterly terrifying.
If there's anything, anything at all that makes you feel nervy, then you should be giving it a go.
4. Aonach Eagach, Glencoe
Seven miles of rocky vertigo on the northern edge of Glencoe, combining spectacular Highland views with the most awesome precipices. It's absolutely bloody petrifying.
It is a place to find out if you've got the bottle.
At some stages, the path narrows to about 18 inches. On one side is an almost sheer 1,000-metre drop, and on the other side is ... another 1,000-metre precipice.
Once you're on it, you can't get off.
5. Paris Roller
A matchless night of inline skating through the very heart of Paris, one of the very best ways to see Paris's sights - at night and at vast speed. It's free and it's every Friday night, with up to 15,000 bladers congregating at Montparnasse before they hare off on a 19-mile circuit of the Paris streets.
Only one rule: You have to be able to control your speed. Take some lessons.
6. Man Versus Horse, Llanwrtyd Wells, Wales
A 23-mile marathon through some of Wales' most outstanding countryside. You can run it - or you can ride it, galloping hell for leather over the Cambrian Mountains.
Me? Horses have never really been my cup of tea. They're huge, they move fast, and they hurt like hell when you fall off
7. The Cresta Run, St Moritz, Switzerland
On the Cresta Run you will reach the fastest speed you can possibly go on land without an engine. It's three-quarters of a mile of adrenalin and unmitigated terror.
The Run has a vertical drop of 514 feet and includes ten high-banked turns that have to be executed perfectly at speeds of up to 80mph. Take the wrong line and you can end up dead.
8. The Party Invite That You Hate
Four years ago I was invited to a school reunion. The thought of it made me feel skin-crawly.
So I went.
If you get an invite that makes your stomach heave, then you've got to go! Simple as that!
Phobias may take a lot of counselling and a lot of work - but they are curable.
Tackling a phobia will challenge some of your most fervently-held beliefs. It may also take a considerable amount of time and commitment.
The moment you've mastered a phobia, they flip from being a trauma into a passion.
10. Have Kids
Whatever you put out to the world, your kids will give you back ten-fold. Whatever your default setting for life, that's what your kids are going to have too. With just a little bit more for spite.
I have one peculiar characteristic which can be summed up in the Scottish word "Thrawn". It means a perverse contrariness.
I was getting on just fine in my Thrawny life - until I had kids. Turns out my two boys are Thrawn Squared.
Eventually I realised something had to give. I'd have to give.
I'd have to evolve.
And that is one of many beautiful things that kids do for you. Uncomfortable though it may be, having children will make any man into a better man. And a happier one too.
HuffPost UK is running a month-long focus around men to highlight the pressures they face around identity and to raise awareness of the epidemic of suicide. To address some of the issues at hand, Building Modern Men presents a snapshot of life for men, the difficulty in expressing emotion, the challenges of speaking out, as well as kick starting conversations around male body image, LGBT identity, male friendship and mental health.
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