In summer 200 km events can be completed without venturing into the hours of darkness, but longer events, and 200s at other times of year all require night riding. Night riding is generally a pleasure: it's cooler, quieter, and picturesque if moonlit. Feeling strong as the pale, flat light of dawn wears on, and the details start to resolve out of the landscape is a unique sensation, though it has to be said that if you're going to have a low time on a ride it will also generally be at this time, circadian rhythms being what they are.
Riding at night involves an element of sleep deprivation, and knowing how this affects you, and what to do when you feel tired is a major part of the achievement of completing long Audax events. It is important to make the distinction between physical and mental fatigue. Physical fatigue involves wear and tear on the muscles and connective tissues, plus the heart and lungs, and tends to be very predictable. (After 100k my knees will start to hurt a bit, but then it won't get any worse after 150k etc.) I embrace physical fatigue with pleasure as I know that after I have eaten and rested I will be even stronger.
Mental fatigue is much harder, linked as it is with mood and cognition. Tackling the extreme forms is straightforward. Even the brightest dynamo lighting doesn't create that much contrast, so resolving the shapes throws more load on the processing power of the brain. There comes a point, if you cycle all through the first night, then into the second, when the road becomes indistinguishable from the verge, which is itself indistinguishable from the trees. The shape of the night sky through the trees takes on human form and swoops low to arrest you. The bike starts to wobble, and gear changes get inexplicably inaccurate. This is mental fatigue, and the treatment for it is sleep.
You can sleep anywhere, but the discerning Audax rider likes to shelter from the wind and rain in bus stops or agricultural buildings before taking a nap. Carrying a reflective space blanket is recommended by some, and indeed they are quite effective at retaining heat. The problem with them is that they are entirely impermeable to water vapour and get very sweaty very quickly. I just use mine as a ground sheet and wrap it loosely round my body. I bought it before the 400, having been up all night partying the night before and knowing I would need to take a nap at some point on the ride. Because it was very neatly packed in the box I didn't take it out to check it before the ride, which was a bad mistake. The box claimed that it was a sleeping bag 220cm long, but when I opened it out it only came up to my chest and was fairly ridiculously wide. This was a dispiriting discovery at 0430hr at some god-forsaken services in East Anglia, but I crawled in, and set the alarm on my digital watch for some two hours hence. Forty-five minutes later I woke up drenched in cold condensation and feeling stiff as a board. One of the few consoling thoughts at the time was that I had not actually yet died of exposure and exhaustion. There was no prospect of further rest, so I staggered round to the services, reconstituted the dust at the base of two plastic cups of coffee and drank them while I stuck the nozzle of the hand dryer in the toilets up my Goretex jacket. This was an improvement, and it looked like the only thing to do was to get going, so going I got, very slowly and stiffly. Fortunately the weather was kind and a beautiful sunny morning developed. About 1100hrs I started to wobble off into the verge again and my eyes wouldn't stay open. By this time it was beautifully warm and I lay down in a field, set my watch to beep in 45 minutes and had the power nap to end all power naps. I awoke completely refreshed and set off knowing that mental fatigue would not prevent me from getting to the finish.
I followed the same tactics on the 600 and the 1200 and it worked very well. Considering how much we do of it, sleeping has not been much studied, but most people know that there are different types of sleep: REM and non-REM sleep. REM is the interesting bit where dreams occur, but the essential bit for avoiding fatigue seems to be the non-REM sleep. This develops in phases, with the deepest (phase IV) sleep at the start of a cycle of sleep gradually lightening over 60 - 90 mins through phases III, II AND I to a period of REM sleep. At this point, you either wake up, or enter another cycle of deep sleep. Successful power nappers hit deep sleep fast, then time their waking to coincide with the lighter phases of sleep (I, REM). The best way of doing this is to resolve to wake up in about an hour, and set your alarm for an hour's time. I find that I wake up a few minutes before the alarm goes off through effort of will. Maybe someone will devise an alarm clock that monitors your EEG and wakes you up at the right time, just as you're coming up through Phase I sleep to REM. Long term use of such a device will turn you into Maggie Thatcher and is not recommended.
The moments of disorientation if you are woken from deep sleep can be confusing, but the world generally swims back into view within a few seconds. Being permanently disorientated must be terrible, but it's not entirely unimaginable. I wonder if some of the other cognitive deficits described in the dementias are in fact some sort of denial type defence mechanism.On the 1200 you can stop to sleep in a "dortoir": usually a large gym hall with judo mats laid on the floor for a couple of hours of kip. The organisers have a system for waking you at a stated time, but this has the disadvantage that you are likely to be woken from deeper sleep, and to you can wake up feeling more hellish than might have been the case. Or maybe it's because it is comfortable and warm you fall into a deeper sleep. After a while though it's all one: never abandoning yourself to sleep is an interesting sensation, but you can't keep it up indefinitely.
Stimulant drugs undoubtedly help you stay awake, but they don't help your personality any, so I confine myself to cups of strong coffee. Some swear by Guarana, which is some sort of stimulant you can buy in herbalists, but the one time I took it I developed a headache for the rest of the night and felt worse than usual. Before the PBP I abstained from all caffeine containing drinks for ten days before the start of the event and didn't drink any coffee until the 700k mark. At this time I had a large and delicious cup of coffee, a chicken and mushroom galette and a banana and honey crepe. This light and stimulating repast enabled me to cycle the next 161km in around 8 hours, with no assistance from any group, which felt like pretty good going at that stage. By that time it was three in the morning and I was starting to feel a bit flat. In retrospect I wish I'd stopped for a nap at that control, but instead I had another cup of coffee and pressed on. This cup of coffee didn't have such miraculous effect.
There's a whole discussion list about bike lighting on the net. Yer gnarliest randonneurs have both a head torch and generator lighting on the bike. For the BPB I was equipped with a halogen front light powered by a Schmidt hub generator. This was superb: quiet, fairly light, easy to push, and you could switch it on and off without dismounting from the bike. In the qualifiers I used a Petzel head torch powered by 3 C cells. This was fairly heavy, but it chucked out a lot of light when the batteries were fresh, and has the advantage that the beam points wherever you look: useful for spotting signs. These measures are more than adequate for tackling even the steepest descent in confidence in the darkness. Even if you only use the generator you need a small torch for finding things in the dark, reading the route sheet and so on. I used a 2 AA cell Maglight with a Velcro headband for hands free operation.
Oncoming cars with badly adjusted headlights form the most serious hazard, as the dazzle can momentarily disconnect you from all of your physical surroundings. Shouting at the f*!@$&s to dip their f*!@$&g lights doesn't really help you or them, though it's an obvious thing to do. The recumbent postion, which allows your eyes to look straight ahead more naturally may actually be a disadvantage in this situation. The best tactic is to hold your offside hand up to shade your eyes from the direct brilliance of the lights and fix your eyes firmly on the nearside road edge. Practicing cycling with your eyes shut when the road is quiet also helps you deal with such situations. Don't keep them shut for too long!
©Douglas Carnall 1999