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Why your hands and feet get cold cycling in winter

George Scott
29 Nov 2021

The science of extremities: keep those fingers and toes warm to ensure enjoyable bike rides this winter

Numb hands after changing a puncture in sub-zero conditions, ice-cold feet after being hit by a sudden downpour – almost every cyclist will have experienced frozen extremities at some point on a winter’s ride. In fact, cold hands and feet are a sure-fire way to guarantee a miserable time on the bike.

While we've never had it better when it comes to winter cycling kit, with advances in fabric technology making it easier than ever to stay warm and dry on the bike, the extremities still remain a challenge for anyone who wants to ride through winter, whatever the weather.

In order to leave you best prepared for the winter ahead, Cyclist has delved deeper into the science behind keeping your hands and feet warm, uncovering why some riders may be more susceptible to the cold than others, before offering eight nuggets of advice to keep you going through the months ahead.

Understanding your internal thermostat

Riding in the snow

First, to understand why our hands and feet are particularly susceptible to the chill, let’s take a look at how the body reacts to a drop in temperature.

'The human body has an optimum temperature range where everything works best, from basic cellular processes right through to vigorous motor movements,' says Jim Pate, senior physiologist at the Centre for Health and Human Performance.

'If you drop below that range in the case of cold, or go too high in the case of heat, those processes begin to break down.

'Fortunately, our bodies have a number of very specific adaptive responses to the cold, which help us to survive in tough conditions.'

That starts with the skin, which transmits information to the thermoregulatory centre of the brain – the hypothalamus – when it detects a change in ambient temperature, providing an early warning of a potential fall in body temperature, ideally kept close to 37 degrees in order to maintain optimum function.

Hypothermia occurs when the body temperature drops below 35 degrees, while frostnip or frostbite can occur when the skin, which has 10 times more cold receptors than warm, is exposed to freezing temperatures.

The hypothalamus, in turn, contains thermal receptors which measure the temperature of blood passing through the brain in order to determine core temperature.

If an alarm bell rings, the hypothalamus triggers one or more of the four physiological responses typically used to generate or shed heat: sweating or dilating the blood vessels when the body is too hot; shivering or constricting blood vessels when it is too cold.

'Shivering is caused by involuntary contractions of the skeletal muscles,' says Pate. ‘These rapid contractions consume energy and help generate the additional heat required by the body.'

If you’re shivering, it's time to take action. 'When you get too cold, your nervous system doesn't work as well and your coordination, concentration and dexterity begin to suffer,' he adds.

Peripheral vasoconstriction, on the other hand, occurs when the vessels that would typically transport warm blood from head to toe, constrict and constrain that blood to the body's core.

'The skin works like a radiator,' says Dr Francesco Del Galdo. 'There is an exchange of heat between the skin and the environment.

'That’s why when it's hot, and there's vasodilation, the skin become red because there is more blood flowing through to the skin, but when it's cold, the skin becomes pale as there is less blood.'

Vasoconstriction is a physiological reflex to protect the brain and vital organs but 'can become a real problem for the extremities in the cold,' says Pate.

While penguins have arteries transporting warm blood next to veins carrying cool blood back to the heart, helping to transfer heat and keeping exposed areas toasty, for us humans, our extremities, by definition the furthest from the core, are the last parts of the body to feel the glowing embers of a pumping heart.

Cycling and Reynaud's syndrome: extreme reactions to cold

Anyone who's ridden through winter will likely have been stung by cold hands or feet, whether due to an unexpected drop in temperature or, quite simply, inadequate clothing. But are some riders more susceptible to the cold than others?

Raynaud’s phenomenon is a condition usually triggered by the cold, causing a lack of blood flow to the extremities and thought to affect up to 10 million people in the UK.

'Raynaud's is an aggressive vasoconstriction of the peripheries – namely the hands and feet, but also the nose and ears,' says Del Galdo, a clinician for Scleroderma & Raynaud's UK. 'The extremities can become excessively cold as a result.’

A Raynaud's attack can be triggered by a small change in temperature and often (but not always) sees the affected skin change colour, from white (during vasoconstriction), to blue (as the blood vessels react), to red (when blood flow returns).

'A reflex of the nerves opens the arteries so that oxygenated blood can return, but this can be extremely uncomfortable or painful,' Del Galdo says.

It is this burning or tingling feeling that characterises Reynaud's over poor circulation or one-off exposure to the cold, he adds.

Raynaud's can be alleviated by physical activity, though cycling in cold conditions is more likely to trigger an attack. Prevention is better than cure and Del Galdo recommends not eating a large meal in the three hours before a ride, layering up to keep the core and extremities warm, avoiding caffeine and nicotine, and warming up before heading out into the cold.

'Swinging the arms and legs can help push blood into the peripheries,' he says. While Raynaud’s is a benign condition in 90 per cent of cases, sufferers should see their GP to rule out an underlying inflammatory condition.

Cold hands, warm heart

Statistics show women are more likely to suffer from Reynaud's than men, according to Del Galdo – in fact, research suggests the extremities of women are more likely to suffer in cold conditions.

A 1998 study by Dr Han Kim of the University of Utah argued that women are more likely to have cold hands than men. A sample of 219 people ranging in age from infants to 84-years-old found women had a mean core temperature of 97.8 degrees Fahrenheit (36.6C), compared with 97.4 degrees (36.3C) for men.

Despite that, the mean hand temperature for women was 87.2 degrees (30.7C), while men recorded an average of 90.0 degrees (32.2C).

The assertion that women are more likely to have cold hands is supported by a 2018 study conducted by biological anthropologists at the University of Cambridge.

According to Stephanie Payne, the study’s lead author, muscle mass is able to predict the rate of heat loss from the hands during severe cold exposure.

'Hands have a large surface area-to-volume ratio, which can be a challenge to maintaining thermal balance in cold conditions,' says Payne.

'We always thought that fat (acting as insulation) was the most crucial factor in thermoregulation, but it’s actually muscle playing the vital role.'

Understanding the effect of body composition is crucial, Payne says, and the study suggests women and children, who are less likely to have a high muscle mass, are more susceptible to the cold.

Surface area-to-volume ratio across the entire body and metabolic rate are also factors, while women's skin is typically thinner and less hairy than men's skin, according to Del Galdo.

However, the physiological factors at play can vary significantly from one person to the next, regardless of gender. For example, a woman can have a higher metabolic rate, higher muscles mass and lower surface area-to-volume ratio than a man.

It's also important to acknowledge the idiosyncratic variables at play, Pate says, including experience in inclement weather, behavioral adaptations to cold conditions and mental resilience.

'There's certainly an element of subjectivity when talking about "feeling" the cold,’ he says.

It never rains but it pours

Unsurprisingly, the key to staying warm is through activity. 'If you are moving then your muscles are consuming energy by contracting,' Pate says.

However, it's rarely that simple as far as your hands and feet are concerned. While you may rock from side-to-side while climbing out of the saddle, or be stamping on the pedals in pursuit of a Strava PB, the hands and feet remain largely inactive when on the bike, and the very nature of our sport leaves your extremities particularly exposed.

'When you leave the house at 08:00, it could easily be six or seven degrees cooler than three hours later,’ says Tom Marchment, co-founder of British glove firm Dissent 133, which has developed a layered glove system for a range of conditions.

'You might warm up when climbing or cool down when descending, or the weather can quickly change and all of a sudden it’s raining.

'That's why layering on our upper bodies works so well but it's important to give our hands the same attention. Not only are they effectively controlling the bike, but they are also so susceptible to changes in the weather.'

Windchill is particularly prevalent for road cyclists – the hands are the least sheltered and active part of the body when on the bike, Pate says – while rain adds another environmental hurdle to overcome.

In fact, freezing cold, wet conditions are among the most challenging for riders – something weather-hardened riders in the UK will be all too familiar with.

'Water has a really high specific heat – in other words, it draws out or absorbs heat very readily,' says Pate. That's a good thing when sweating, as the water droplets that form on the skin evaporate and take away excess heat.

'The problem is, if you get wet in cold weather, that water is going to leach heat out of you at a faster rate than air would,' he adds.

Nature, it seems, is against cyclists but winter needn’t be a lost cause, nor should you be confined to the smart trainer between November and March. Below are eight tips to help keep your hands and feet warm through winter.

Eight tips to keep your hands and feet warm when cycling in winter

1. Keep moving

Let's start with the basics – keep moving in order to generate heat. 'In most cases, unless you are really, really cold, if you are active and exercising then you probably won't be shivering much,' says Pate.

'It's when you stop that your core temperature drops significantly.'

While physical exercise alone may not be enough to keep your extremities warm, for reasons we've already uncovered, by limiting the time spent standing at the roadside, you're giving yourself a head start.

By extension, keeping on top of your equipment – fitting tough winter tyres to prevent punctures and carrying an effective pump or CO2 inflator – will limit unnecessary stops in inclement weather.

2. Stay loose

While vasoconstriction is the body's natural defence against the cold, riders can take steps to alleviate the effects of contracting blood vessels – or at least, not compound them.

Pate advises maintaining a loose grip on the handlebar – 'the sustained contraction of gripping tightly makes it more difficult to get blood into those areas,' he says – while you can also promote blood flow to the feet by ensuring your shoes aren’t too tight.

'I'm sure everybody has done it from time to time, cranked their shoes up all the way and got numb toes,' he adds. Wearing socks that are too thick can also restrict blood blow – stick to one pair, made from a naturally insulating material like merino wool.

3. Material matters

Committed winter riders, keen to get out whatever the weather, will encounter a variety of conditions, from to sub-zero, bluebird mornings to single-figure temperatures and torrential rain.

Investing in a range of winter gloves, or layering your gloves according to the conditions, will help you stay warm, whatever the weather.

'Like your upper body, it’s a case of making a decision about what to wear so you’re not having to make compromises to keep your hands warm,' says Marchment.

Pate turns to neoprene when riding in persistently wet conditions, while Marchment recommends a silk liner glove beneath a thermal layer on cold days.

'It adds another layer of lightweight insulation without too much bulk,' he says, 'It's like a wicking base layer and will pull moisture away from the hand.'

4. Core belief

While it may seem counterintuitive to focus on your core in order to keep your extremities warm, if your core temperature begins to drop, your body begins to limit blood flow to those parts of your body that don’t house your vital organs.

Use breathable layers to avoid excessive sweating, which in turn can make you cold, while you should also stash a lightweight emergency jacket or gilet in your back pocket in case the weather turns.

'Keeping your forearms well insulated is also important, as heat can be lost from blood before it reaches your hands if your arms are cold,' says Marchment.

5. Cafe culture

Welsh cafe stop

The mid-ride coffee stop can be your saving grace on a cold, wet ride, but emerging from the warm cocoon of the cafe and jumping back on the bike can also be a daunting prospect.

'When you take your gloves off at the cafe, don't just ball them up and stuff them in your helmet,’ says Pate, who advises wringing them out or finding a radiator to dry wet clothing.

'Wrap your hands around a warm drink and and get some heat into them before you head back out,' he adds. Otherwise, filling your bidon with a hot drink, or taking out an insulated bottle filled with tea, can provide essential mid-ride warmth.

6. Accessorise

Mudguards are a staple of any winter bike and are an essential accessory when trying to keep your feet warm and dry.

'At the end of the day, if you're not spraying water all over your feet and back, you won't get dirty, wet and cold as easily,' says Marchment.

'Neither will the people riding behind you, which is important when you're on a social ride together.'

If you have a dedicated winter road bike, you’ll likely have the necessary room and eyelets for full mudguards, but even clip-on guards can work wonders on a race bike with limited clearance.

7. Get creative

Investing in the right gear is key to surviving winter on the bike but you can also get creative with more affordable solutions.

Marchment recommends using electrical tape to cover the vents on your cycling shoes, particularly on the sole, while some riders use cling film or foil to add an insulating layer.

Marchment doesn't go that far: 'I use warm socks, a shoe, a Belgian bootie and then a waterproof overshoe,’ he says. ‘That gives you some additional thermal layering on the outside, without restricting the foot.’

8. Home front

Despite everything we’ve covered, there's still a chance your extremities may suffer at some point through winter. If that's the case, avoid the temptation to defrost your hands or feet under a running tap or hairdryer when you return home.

'At best, the sudden change in temperature can be extremely painful,' says Pate. 'At worst, your skin might be numb and you'll burn yourself.'

Instead, you should gently rewarm your extremities. Swing your arms above your head and your legs from back to front to coax warm blood into your fingers and toes (another tip when emerging from the mid-ride cafe).

Then it's time to enjoy a hot beverage or a bowl of soup.

Need more help and inspiration? Head to our winter cycling hub page for in-depth winter kit and bike advice from Cyclist's team of experts.

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