66. Riding in hot weather – avoiding dehydration

The article is highly relevant, particularly since summers in the UK are getting hotter and hotter. Riding in extreme high temperatures continues to pose a real risk of dehydration, heat exhaustion, and impaired concentration for motorcyclists. The physiological explanations (sweating, fluid and electrolyte loss, impact on kidney function, early fatigue, and later confusion) are all accurate and still supported by modern sports medicine and physiology research. One correction is that modern research suggests moderate caffeine intake is not strongly diuretic in habitual consumers but energy drinks can be counterproductive due to high sugar content. Heat stress is compounded by full protective gear but modern ventilated jackets can aid air flow and cooling if humidity is not too high. It’s also possible to get sunburn through a visor; packing and using sunscreen is a good idea. Don’t ignore the signs of heat stress. Dizziness, headache, nausea, rapid pulse, or cramps can indicate heat exhaustion before severe dehydration sets in.


Riding in hot weather – avoiding dehydration

It always seems to happen. One week I’m riding around wishing I’d remembered to wear the heated waistcoat, then we get a few days of ‘scorchio’ weather. Riding a motorcycle in protective kit on a hot day sets up a unique combination of overheating and sweating, and a cooling and evaporating breeze. The body’s physiological functions only work in a narrow range and if we get too hot or cold, we get disorientated or worse. So the body tries to maintain temperature of around 37 degrees by sweating. The result is a high risk of dehydration at the same time as we’re struggling to stay cool. So what are the dangers of running short of body fluid?

Body fluid and electrolytes are vital to the function of the body’s organs. If they are lost through sweating and if they are not replaced, we suffer dehydration. In the early stages, we get rapidly fatigued and start to lose concentration. In the later stages more serious confusion sets in, and the body’s metabolic functions start to be affected. Not good. And that’s why I send out a notice to riders to ensure that when they attend a Survival Skills advanced rider training course, that they pack some water.

So what are the symptoms of dehydration? A good sign that we are dehydrated is not “feeling thirsty”, it’s not needing to pee! That tells us kidney function is already shutting down to save fluids. By the time we do feel thirsty, with dry lips and a dry mouth, then we are already well into the early stages of dehydration.

Most UK riders are oblivious to just how real a problem this, even when riding at home in a British summer. In countries like Australia, New Zealand, South Africa and the US where they ride long distances in hot and dry conditions, they are much more aware of the risks. You’ll also see racers taking on board fluids just before the start. But dehydration doesn’t only happen to racers. Whilst we’re not working physically so hard, we’re often exposed to that cooling breeze for longer.

So what can we do to prevent dehydration?

Planning ahead is the answer. We can start by pre-loading with fluid before we go out. For sports like cycling and soccer, it’s recommended that we drink around half a litre (roughly a pint) of fluid a couple of hours before we begin. Then around 15 minutes before setting off, aim to drink another half litre.

On the move, we need to keep replenishing fluids. It’s easy enough to take a bottle of water with us, so we can take a drink when we stop. For sporting activities, it’s recommended that we take around 100-150ml every 15 minutes or so when exercising – that would be around a half-litre bottle of water every hour. Given a particularly hot day, that’s probably not far off what we should be drinking on a bike. I took a Hopp Rider Training day at Cadwell Park on a warm autumn day, and we were reminded to get some water on board before going on track, and regularly reminded to rehydrate between track sessions. Doing it right, we should be making regular loo stops too. If that’s inconvenient, so be it. It’s better than the side effects from dehydration.

Riding alone, we can stop when we like, but on a bike with a 250 mile tank range, don’t wait till refuelling stops. Definitely make intermediate stops – remember, if you feel thirsty, you are already dehydrated. Group rides tend to go on too long, and we’re all dependent on the leader deciding when to pull up. So if you’re organising a group ride and you know it’s going to be a hot day, then factor in short breaks at regular intervals, and try to get people to use the opportunity to top up – you don’t want dehydrated and underperforming riders with you.

There’s a lot of marketing surrounding isotonic fluids – these are basically water plus the electrolytes we lose in sweat, so they have the advantage of keeping the chemical balance of the body right. You’ll find them in most service stations. Isotonic drinks also come in powder form – you can buy tubs of the stuff from any cycle shop and make up a couple of litres for the ride.

Personally I’m not fond of fizzy canned drinks because they are generally sweet and sticky. Coffee is generally considered a diuretic (ie it makes you pee more) but lately there’s been some debate about whether the old advice to avoid caffeine-based drinks is actually correct, although it’s generally accepted that the so-called energy drinks aren’t good for rehydrating. Personally I prefer tea – it’s not nearly so strong a diuretic and I like it!

However, they all cost a lot more than plain tap water!

So what to carry fluids in? I avoid buying plastic bottled water, partly because the plastic is liable to split when wedged into a pannier or under an elastic strap, and partly for environmental reasons. Any cycle shop will sell you a plastic water bottle – they are (just about) unbreakable and will squash – or an aluminium bottle. A little more cash will get you an insulated plastic cycle bottle or a Camelbak which is a plastic bladder that sits in a backpack harness – fill either with ice cubes in it, top up with water and even on a hot day, you’ll have something cool to drink for a hour or so.

A couple of final warnings. Steer well clear of alcohol. It might be tempting to sink a nice cold pint “because I’ll be well under the limit” but if you’re rehydrating, the alcohol will be absorbed faster and be even more disorientating than normal.

And… DON’T drink ice-cold water. The thermal shock of pouring ice-cold fluids into the stomach fools the body into thinking it needs to shut down the sweating mechanism. That’s definitely not what we want.

18. Staying awake

If anything, this article was another to pick up a riding issue well before it became better known. Drowsiness remains one of the most consistently underestimated risk factors in road safety, particularly among private motorists and motorcyclists, and we can fall asleep anywhere. Prof. Jim Horne’s research was at the time I reported hot off the press, but now there’s a deeper body of evidence backing up his work. The central premise — that sleepiness kills more people than drink-driving — is broadly consistent with the research base then and now, as modern studies continue to show that fatigue is strongly associated with serious and fatal collisions and still under-reported. Yet the cultural blind spot — acknowledging drink-driving risk but dismissing fatigue — is still very real.

02:00–06:00 remains the highest-risk window and the mid-afternoon dip is well established between 13:00–15:00. The observation that riders feel tired well before control degrades, underestimate how badly they are performing, and push on because “we’re nearly there”, is strongly supported by human-factors research. It’s a danger on group rides, and I have experienced it myself, because experienced riders — who often volunteer to lead — often underestimate how tired other riders are, and because nobody wants to be the rider to stop the group. The phenomenon of micro-sleeps remains one of the most misunderstood fatigue mechanisms, and the “long blink” warning is accurate. Caffeine can temporarily improve alertness, but it does not reverse sleep debt. One modern insight worth adding is that fatigue is cumulative and many riders start long journeys already impaired. It strengthens the “planning matters” argument, before the key is turned. We can fall asleep anywhere.


Staying Awake

This article was first written in the early 2000s, and was prompted by research by Professor Jim Horne of Loughborough University’s Sleep Research Centre. His findings indicated that more people are killed on UK roads due to sleepiness than through drinking and driving. Whilst we generally think of monotonous roads such as motorways are as the problem areas, because of the high speeds and serious consequences are often serious, we can fall asleep anywhere. Whilst bus, truck and coach drivers are strictly monitored, drivers and riders are particularly at risk because there are no rules which regulate the amount we can drive or ride. And as a group, motorcyclists seem to be blissfully unaware of the problems.

So why do we have problems staying awake? The obvious one is spending too long on the road at any one time. I discovered it was a particular issue in New Zealand, because towns are far apart and the roads are slow, but clearly if we’re riding from London to Edinburgh, that’s a long way and if we attempt it in one hit, we will get physically tired and sleepy.

Less obvious are the body’s natural biorhythms. We are programmed to fall asleep at certain times. Not surprisingly the highest risk time is between 2am and 6am, but fewer people are aware there is a similar period between 12am and 4pm, which is made worse if you have had a heavy meal or if you are an older driver. Shiftworkers are particularly at risk because their sleep patterns are disrupted.

So first and foremost, we should try to avoid the risk of getting sleepy in the first place. And that means planning a journey to avoid excessive daily mileages. We should also factor in breaks. At least fifteen minutes in every two hours is recommended, but regular longer breaks are a good idea, with a nap as needed when we start to feel sleepy. And avoid heavy meals during breaks and strong coffee or ‘energy’ drinks. The former divert blood to the digestive system away from the brain, and the latter only provide a very limited, short term lift.

So how do we know we’re at risk? We get some early warning. Simulator research shows a driver will often start to feel sleepy around forty minutes before the real problems occur, but typically we try to ride through this stage rather than pull over and take a break, frequently because we’re close to the end of our journey. At the same time, we don’t realise how badly we are riding, even though others often notice. Witnesses to accidents involving a dozing driver often report that the vehicle was being driven erratically before the accident occurred.

As soon as we realise we’re getting tired, we should stop as soon as it is safe. If you are on the motorway, don’t push on to the next service area, pull off at the next exit. Common ‘cures’ such as opening the windows / flipping up the visor, singing to ourselves or turning the stereo up loud don’t seem to work.

The next stage is something called ‘micro-sleep’, where we doze off for a second or two. Ever had that really disconcerting ‘long blink’ when you suddenly discover the truck ahead is no long three or four seconds away but right in front of the wheel? That’s a micro-sleep.

If we start to be concerned about keeping our eyes open, then stop IMMEDIATELY, even on the motorway. The hard shoulder is for emergency use and in my opinion this is an emergency. Although the police might not interpret it that way, if you get off the bike and kick the tyres or something, even a five minute stop should wake you up enough to get safely to the next exit, where you can leave and take a proper break.

It’s likely that tiredness-related problems are at the root of some seemingly-inexplicable group riding crashes. I know that I had a crash on one of my rides that was fatigue-related. The rider had started early because he’d had a long way to ride. I had tried to cover too many miles on the road and hadn’t factored in sufficient breaks. With around forty minutes to the end of the ride, he lost concentration on a bend and went off the road. He was unhurt but the bike was a write-off. So if you’re organising a ride, watch for signs. And if you’re in a group ride and YOU start to feel sleepy, stop the entire group rather than try to push on to avoid inconveniencing everyone else.

And finally, just in case you think you can’t fall asleep on a bike, you can! It happened to me years ago when I was a courier.

It was a hot summer’s day, around 3pm. I’d been riding since about 9am with just a couple of short breaks and had just passed the last exit before a 20 mile stretch of the M26/M25 where there is no exit, when I started to feel really sleepy. I knew I was riding badly, and then I experienced a micro-sleep. I suddenly found myself about five metres behind a truck.

But I carried on. I lifted the visor, started trying to sing myself away, and made the mistake of trying to push on to the next exit because of that rule about not stopping on the hard shoulder.

Bad move… five minutes later I found myself riding diagonally across the hard shoulder, heading for a grass embankment and with the left hand indicator on.

The weird thing was I could remember a little dream of seeing the exit ahead. This time I stopped, got off the bike and took my helmet off, walked around and jumped up and down for a few minutes before getting back on the bike and pulling off at the next exit. I found a stretch of grass beside the road, and had a kip for half an hour. That way, both rider and parcel made it to their destination, just a few minutes late.

I posted this story to a motorcycling group elsewhere. To my surprise, few people took the danger of drowsiness whilst riding at face value and hardly anyone considered it as a real (or even potential) problem.

A scary number came up with a “I get tired but I continue to ride/drive whilst singing/looking around/jumping up and down and that works for me” rationale. One very experienced rider claimed, he could tell non-dangerous tiredness from dangerous tiredness. Yeah, right.

The interesting thing is that the report highlighted that people do not see driving whilst tired as a high risk activity, and here was a group of experienced riders responding in exactly the way the report predicted.

My guess is that what’s happened is that they have driven or ridden many times whilst tired and got away with it. So they dismiss the dangers as negligible, despite solid evidence to the contrary. It’s the same “I can handle it” attitude that drink drivers habitually use to excuse their behaviour, right up to the day they fail to handle it. I guess we need a lot of educating before we believe the dangers of our behaviour.

17. Staying Warm on two wheels

Physics doesn’t change. Only our understanding of the principles does. Given how long ago I wrote this article, it has not just stood up well to the passage of years, I’d venture to say that it was is quietly ahead of its time, at least in the world of motorcycling: the emphasis on core temperature, cognition and risk perception, and decision-making, rather than just comfort, aligns very closely with how cold-weather risk is framed today in both occupational safety and human-factors research. Hypothermia is insidious and often unrecognised and framing getting cold as a decision-making and control problem is crucial, and extends far beyond a comfort issue, something still under-emphasised in mainstream motorcycling advice. That reinforces why riders underestimate cold-related risk. The central insight — cold hands are a symptom of falling core temperature — is the core of the article and scientifically valid as is the explanation of insulation as rate-of-loss reduction rather than heat retention. This is a mistake riders still make even today, relying on layering too much.

Where I writing the article today, I would point out that much of my critique of heated grips is fair, but they are more reliable and somewhat more effective than the ones I struggled with back in my courier days, but they are still more useful as a supplement to heated clothing, but not a solution, particularly on a long ride.


Staying Warm on two wheels

Motorcycles and cold weather aren’t entirely compatible. Whilst the biggest winter risk to riding in the UK is ice, the subtle disorientation caused by hypothermia isn’t that far behind. The wind chill factor is considerable on a bike, and the hands are stuck out in the wind. They also have a large surface area to lose heat from, and so are the first part of the body that we notice getting cold. Unfortunately, because gloves still need to allow us to operate the controls, they are also probably the most difficult part of the body to keep warm. Over the years, I tried all sorts of ways of keeping my hands warm. I tried some pretty expensive kit as well as ideas I knocked up myself for nothing. So have a read, learn from my experience, and before you dash out and spend big cash too, don’t make the same mistakes I did.

In an attempt to keep my hands warm I’ve tried:-

thick gloves
thermal gloves
World War 2 flying gloves (really!)
skiing gloves
silk inner gloves
thermal inners
overmitts
handlebar muffs
cut down milk containers
heated inners
heated handlebar grips

But before I discuss how well they worked – or didn’t work – let’s consider just why hypothermia isn’t uncommon when riding a bike.

Heat is lost from the body by three routes:

radiation
convection
conduction

Fairly obviously, the blood flows out down our arms and legs to hands and feet, and back to the heart. But when it’s cold, the blood passing down arms and legs is cooled by the windblast – their large surfaces act as radiators – and returned to the core of the body. Now it has to be re-heated before being pumped round the body again. The body can cope with mild cooling – it just turns up the heat by burning more fuel – but there’s a limit. Once we start losing heat faster than the body’s self-warming process can cope with, we start losing heat from the body’s core. And the steeper the temperature gradient (ie, how cold it is), the faster we chill.

Now, we don’t really feel any of that, but what we feel is the next stage. As our core temperature starts to fall, the circulation of warm blood to the surface capillaries begins to shut down to reduce further heat loss. Skin feels cold to the touch. Go a stage further and the blood supply to the body’s extremities also starts to shut down – now it’s not just skin that’s cold, but our hands and feet, and eventually even our arms and legs.

What are the effects of this chilling? When are arms and legs get cold, the muscles operating our fingers, hands and feet become stiff and unresponsive. And we start to struggle to control the bike. I remember one icy ride from London to Kent when I couldn’t actually change gear for the last ten minutes.

That’s bad enough, but it gets worse. We also lose heat through our neck and head, and that means the brain is affected too. We start losing focus and making bad decisions.

So that’s hypothermia. And it sets in surprisingly easily on a bike. If you’ve ever reached the stage of shivering uncontrollably, you’re in the early stages of hypothermia. . This is not idle speculation – this comes straight from sports physiology research.

So what was the mistake I made? It’s pretty obvious when you read the list above – they were all attempts to keep my hands warm. Unfortunately, that’s treating the SYMPTOMS rather than the DISEASE.

Let’s just recall what thermally-insulated clothing does. We think of it as ‘retaining’ heat, but that’s not actually how it works. It SLOWS DOWN the rate of heat loss.

So here are two points to think about:

thermal insulation only works up to the point where the temperature gradient across the insulation is steep enough for the rate of heat loss to exceed the body’s ability to heat itself. Once temperatures dip low enough, from that point on, we are going to chill. For clothing with good thermal insulation, that threshold temperature is lower.

if we only ride short distances, thermal insulation may slow down the rate of heat less enough that we don’t notice the chilling effect of cold weather. But on a longer ride in the same clothing, we will continue to lose heat for as long as we’re riding, and then all that our thermal clothing can do, no matter how good it is, is to delay the onset of chilling. It prolongs the agony, as it were. This is a serious problem if you are habitually a short distance rider and suddenly do a long trip. It took me years to understand why the clothing that kept me nice and warm on short rides let me get so cold on long runs.

So the key point is that whilst moderately chilly weather may be tolerable for short rides, as soon as the temperature really dips or we take a long ride, we’re going to chill. Circulation to the arms, legs and brain are all reduced, and eventually we’ll lose our mental focus too.

One obvious solution is to keep adding thermal insulation until we stay toasty. That’s the idea behind ‘layering’. But after a bit, thick gloves with inners get too bulky to be easy to use, and we end up looking like the Michelin Man – try looking over your shoulder!

So let’s step backwards a bit, and recall that if we keep the core temperture high, blood keeps circulating. But how can we supplement the body’s own ability to supply enough extra heat?

Well, the obvious solution if hands are cold is to use something to heat the hands – heated grips and gloves . But remember – this is the symptom, not the disease. They might make our fingers feel warm but they are very inefficient – most of the heat produced is lost again, either by conduction down the metal bars or radiation from the back of the glove. My experience is that I still got physically cold even if my fingers felt warm, probably because the warm fingers ‘fool’ the brain into opening up capillaries to blood flow, which then loses heat. And as a secondary problem, I’ve found heated grips and gloves fail very quickly because of the constant flexing. I generally reckoned on a year for heated grips before the wiring failed and one winter for the gloves, sometimes just a couple of months. It’s the heating elements that go in gloves and the feed wire on the throttle side with grips.

So can we heat the core directly? We can, by using heated clothing. A heated jacket or waistcoat adds heat where it’s needed, and given the same insulation, the result is that we push the point where we start to chill to a lower temperature. With core temperature maintained, so is circulation to the extremities and so hands and feet get a constant supply of warm blood.

In my experience of riding through really cold weather – I was a blood runner for several years, being called out at all hours of the night including in mid-winter – a heated waistcoat may not completely overcome the cooling effect but goes a long way towards it – on one 3am ride in January when it was -10c, my fingers still got cold but they didn’t go numb. I would have struggled to complete the ride without the waistcoat. I’ve found that if it’s chilly (10 – 5C) wearing a long-sleeved shirt, a light fleece then my heated waistcoat keeps me warm. If it’s cold (around 0) I wear the fleece over the waistcoatr. Below zero, I put unlined waterproofs over my riding suit, and that is sufficient to deal with a three hour riding down to about -10C.

Heated waistcoats are available for around £100 and my experience is also that they last much longer. My first Gerbing waistcoat lasted a decade, and my replacement from Exo2 is even older. Only the oldest bikes will have problems with a waistcoat – they draw no more than about 30 watts – half a halogen headlight bulb. It’s also possible to daisy-chain heated gloves, socks, leggings and collars from some manufacturers, but make sure your bike’s alternator can cope with all that lot.

Personally, I’d avoid a heated jacket. You can wear a heated waistcoat under several layers of insulation BEFORE putting a jacket on – you can’t do this if the heating element is built in to the jacket.

Final tip – plug the leaks! Keep wind out of your clothing by tightening wrist straps, using a scarf or neckwarmer and zipping jackets to trousers or wearing one-piece suits. Several thin layers are better than one thick one, unless it is a fleece – the idea is to trap air and stop it moving. If you have a separate jacket, bib-and-brace type trousers help keep the kidneys warm. A cheap one piece rain suit over the top will do wonders if you have separate jacket and jeans.

And a word of warning – don’t put the heated waistcoat next to the skin – the heating element can get pretty hot and you will end up looking like you barbecued yourself! You can get inline temperture controllers, or just wire in a simple on-off switch on the bike’s dash. Don’t forget to fit an inline fuse to avoid self-immolation.

If you want to stay warm on a bike this winter, spend some smart money on a heated waistcoat!