My biggest barrier to success next year is my weight. I'm not a particularly fat bloke, this morning I was 86.7kg (which is in the healthy BMI range if you're comfortably over 6' like I am). I've been a lot more - I was around 100kg a couple of years ago when I first started caring about these things.
Anyway, the biggest barrier to performance is weight. I plotted my parkrun times against the weight I was on that day. I was absolutely shocked at the direct correlation.
The exception is the last couple of weeks - the spike in weight was a result of going on holiday and coming back 4kg heavier 10 days later!. Ignoring that bit, it's blindingly obvious:
The lighter I am the faster I am.
The biggest (certainly my biggest) barrier to reaching my race weight (whatever that turns out to be!) is alcohol. However, it's not just the alcohol, it's everything that comes with it.
You consume absolutely bucket loads of empty (useless) carbs during a night on the lash. The sleep you get afterwards is poor quality so you wake up tired, and it's not restorative so you don't benefit from the exercise you got that day so much. The next day you're knackered and more likely to crave yet more junk carbs.
I really enjoy a night on the town on days where I've had fantastic training sessions (full to the brim with happy-happy endorphins) and that's absolutely the worst way to "recover" from a good session, undoing all the good work and then some and not giving your body the fuel and nutrition it craves to rebuild after the damage of exercise. As if that wasn't bad enough, I'm less likely to complete the sessions I had scheduled for the next day (and if I do make it, it will be a junk session due to me being knackered and weak).
I'm incapable of doing things by halves, so "no more than two pints" or "just once per week" will never work, I know myself too well to kid myself that such initiatives will ever succeed.
So, just this once, and about just this thing, I'm saying:
No more alcohol until after IM Wales.