What does it take to get to the start line of a 24hr race ready to go? Well, a lot of things. Fortunately we are all different; what specifically will work for you is almost certainly going to be different from what works for the next rider. Having done a few of these events to varying degrees of success I want to share some of my experiences with race preparation.
This isn't going to detail any sort of training program for 2 reasons. Firstly, I'm not a qualified coach and secondly, everyone is different. You could copy what someone else has done and get nowhere with it. If you're determined on having a training program you'll have to figure out what you're going to do either on your own or with your coach.
I will suggest a few things, though, that have got me through the tough times in these difficult events.
A few easy rides a week will give you a base of fitness to work off but if you want to excel you're going to have to do some decent training. Even if your training is haphazard at least when you start to hurt during the race you'll have some confidence that you've already put yourself through something similar and lived to tell the tale!
Make yourself as bulletproof as you can. Your back, shoulders and forearms will take a pounding. Most cyclists have strong legs but the ongoing demands on the rest of the body during long distance mountain biking make it easy to pick up some silly injury elsewhere that can potentially ruin your race.
Keep in mind that road riding will NOT stress your upper body the way mountain biking will. Which brings me to my next point.
When you can, train on your mountain bike. Try to find similar terrain to what you're expecting on race day and train on that. Ideally, ride the course in advance.
Ride at night! There is plenty of darkness during 24hr races - make it part of your training and you'll feel a lot more comfortable. Speaking of night riding, it's a good idea to learn to manage your eye wear. Where I live it's often quite humid so I'm constantly trying to stop my glasses fogging up on night rides. Resist the temptation to do away with them. Without clear vision your race can be over very quickly.
EAT and DRINK while you train
Eat and drink as you ride during training. I don't mean sit spread legged at every cafe along the way, rather, fuel yourself in training as you would in a race. Unless you've got a hell of a crew I doubt they'll be handing you a skinny macchiato and warm banana bread! You might get a sandwich and a coke if you're lucky! Also you can save heaps of time during the race if you can eat and drink while you keep your bike moving forward. Learn to chuck down food and drink quickly. You may only get small windows of opportunity on course to take on nutrition.
Try not to overdo it, but make sure you've completed a few rides that makes your mom despair before race day. During the race you could be on your bike for nearly the whole 24hrs so you want to be confident that you can cope with that. Your body and mind will waver over the course of a long ride so do it on a Saturday ride with mates when it doesn't matter. That way you know what to expect come race day.
DRESS for success
You've got 5 contact points on a bike. Look after them. Find a pair of shoes that you like and buy them, regardless of price. Gloves and grips, knicks and saddle; don't skimp on any of these areas. Not so important but a free hint: Get glasses that sit nicely with your helmet. It can drive you crazy if they don't. Not just when you're wearing your glasses but think about if you need to take them off and jam them in the vents in your helmet (I use the Giro Atmos and Oakley Radars, they work perfectly together.)
Oh, wahh, it's raining/cold/hot/windy...and? If the weather turns during the race they won't bring everyone inside and make it a spin class. Mountain biking can be as much a battle against the elements and the course as it is against your competitors. Learn what layers of clothing you're comfortable wearing and how your nutrition intake varies during different weather conditions.
My clothing progression goes something like this as the temperature drops: Start in full finger gloves, jersey, bib knicks, socks, shoes, well vented helmet and glasses. Add arm-warmers, undershirt, long-sleeve jersey, wind vest, long Skins over knicks, windproof gloves, cap under helmet, Seal Skinz socks, Buff around neck
Depending on how heavy the rain is one of those goofy cycling caps will keep the rain off your glasses and if it's really coming down the Gore-Tex jacket will keep you dry(er). Don't be afraid to rock a good old fashioned mud guard to keep your butt dry.
Pre race NUTRITION
Every week there seems to be new research about the ideal pre race meal. My favorites are pizza and pasta. I don't know if they are good or not for carbohydrate loading - if that's even still the thing to do, but what I can tell you is that every night before a big race for the last 17 years dinner has consisted of spaghetti, lasagna or chicken pizza and too much garlic bread. It's almost a ritual now.
The morning of the race eat what you normally would before a big ride. What you eat at that time isn't going to have a big impact on your performance. The closer you can keep your routine to normal the more relaxed you'll be. At any rate, the energy stored in your body will be depleted after a few hours so focus more on what you'll consume during the race rather than changing up what you have that morning.
Getting into the right MINDSET
As for mental preparation there are countless theories, some very well researched and thought out, others....not so much.
I'd suggest the following; relax, hydrate, do something that takes your mind off the race. I'll often watch a movie that I find inspiring (so dorky!) 24 Solo, Remember the Titans, Hawaiian Ironman replays.
If you go to bed and can't sleep, get up and do something constructive. Fill bottles, polish your frame, don't just lay in bed and worry. It's too easy to stress yourself out before the race even starts if you overthink it.
Ideally your preparation will get you to the start line fit, healthy, full of beans and perhaps most importantly confident in your ability to cope with what you're about to do. 24Hr racing can be great fun and a few small changes in your approach can make a big difference on the day.
Now get off the computer, stick your helmet on and find some single track.