Your legs are aching, they feel hollow, there's nothing left, you feel like you're going to be sick. Quad and calf torture comes in the bucket-load each time the road goes up, your club mates tell you to "dig in", someone gives you a push and you manage to cling on for another mile.
By the time you realise what's happening, it's too late. There's no Porte in this storm, at your beckon to nip back to the team car for nutrition so you start digging in your pockets, which yields the half-eaten energy bar you had at the top of the last climb and the gel that you've been saving just in case things go south. Both get smashed down in short order; you put the gel packet back in your jersey pocket and your hand returns to the bars in a sticky mess. It makes you feel a bit more sick, as if you could feel any worse.
You're rocking in the saddle now, your head is bobbing from side-to-side, your shoulders have dropped. You're not going to be able to tolerate this misery much longer. All you can focus on is the wheel in front, the rest of the world has some kind of Instagram filter on it - that one that makes things fuzzy around the edges. Another dig... another push from your club mate. Not long now...
When it happens, it comes without fanfare or surprise. That half a wheel becomes a bike length, you click up the cassette - maybe a change of cadence will get you up this lump in the road, you ask your legs... they turn the other cheek. Sorry, we've checked out, you're on your own. That bike length is now 5, the small chainring beckons, your vision is now a pinprick in a fuzzy mush of greenery, the only thing you can see is your front wheel, Tarmac and your mates disappearing up the road.
Into the 36 and the granny at the back and that's it. Sit up, gasp for oxygen and try and get the world to return to normal. It's 10miles back and that gel you choked down still hasn't kicked in. As you try to regain energy, you go over the ride and identify the point at which you should've eaten, you've been fine if you'd had something at the bottom of that climb, hindsight is wonderful. Halfway through the ride back your legs start to work again and you can again start to pedal with some conviction.
You hate it, that feeling when every ounce of energy in your body disappears. It's the worst. But somehow so, so satisfying that you've done this to yourself.