Why cycling in cold weather is good for you

© Kathrin Schafbauer

Exciting new scientific research suggests that cold weather training burns more body fat, strengthens your heart and lungs, and boosts your mood over winter.

Some cyclists avoid riding over the winter months, perhaps thinking the chilly weather makes them vulnerable to illness or injuries, or simply because they hate the cold. But new scientific research suggests that cold weather training provides an incredibly positive boost to your health.

A series of medical studies have shown that exposure to the cold helps to raise your metabolism, burn body fat, improve your cardiopulmonary health (the efficiency of your heart and lungs), and enhance your mood. So if you keep cycling outside over the winter months, you will enjoy great improvements in your physical and mental health.

The new research shows that cold weather exercise triggers a host of positive effects on the human body. The normal temperature of your body is 37°C, but when you exercise in the cold your heart and lungs have to work harder to keep your body warm. Blood flow to your extremities is reduced, your breathing rate quickens, and more oxygen is sent to your muscles.

Performance increase for lungs and heart

Because your body has to work more efficiently to pump blood and oxygen around your body, these physiological changes sharpen up the performance of your heart and lungs. That is why Professor Wouter van Marken Lichtenbelt of Maastricht University, one of the researchers who have studied the benefits of the cold, insists that cold exposure “helps to train the cardiovascular system” – a welcome benefit for any cyclist.

© Kathrin Schafbauer

Cold exposure also triggers a spike in your fat-burning metabolism, as your body burns more calories in an effort to stay warm. A research paper by Professor van Marken Lichtenbelt confirmed that cold exposure boosts non-shivering thermogenesis (NST) – the technical term for the cold-induced spike in your metabolism – by up to 30%. Separate research in the American Journal of Human Biology found that winter hikes burn 34% more calories than hikes in normal conditions.

And another paper found that simply turning down your thermostat at night and sleeping in a cooler bedroom raises your metabolism by 10%. As Professor van Marken Lichtenbelt has concluded: “We suggest that regular exposure to mild cold may provide a healthy and sustainable alternative strategy for increasing energy expenditure” – more positive news for cyclists looking to trim their body weight over winter.

Exciting new areas: cold weather training helps to reduce “brown fat”

But one of the most exciting new areas of research on cold weather training focuses on a mysterious substance known as “brown fat”. This unique form of body fat is located around your neck, collar bones and back. Its role is to burn energy for heat, which is why some scientists now describe brown fat as “the fat that makes you thin.” This brown fat is triggered into action by exposure to the cold.

And it is believed to have played an important role in our evolutionary past, helping to keep us warm when exposed to extreme cold. In fact, brown fat is so powerful it can produce 300 times more heat than a gram of any other tissue in the body.

To generate this heat, your brown fat burns glucose (sugars) and lipids (fats) for fuel, which may be why cold exposure helps you to lose weight. “The energy for that heat production has got to be drawn from somewhere – and it’s partly from fat in the body, but the other important source is glucose,” explains Professor Mike Symonds of the University of Nottingham’s School of Medicine. “And that should be beneficial in terms of keeping your weight down and minimising excess fat deposition.”

One research paper in the Journal of Clinical Investigation found that even a small dose of cold exposure – around two hours a day for six weeks – can slash body fat by 5.2%. Research by the University of Nottingham has also shown that cold exposure leads to lower levels of circulating fatty acids and triglycerides, which are linked to heart disease and diabetes.

© Alexander Böhle

Impact of cold weather training on mental health

But the advantages of cold exposure are not just limited to the body. Research suggests that cold weather exercise can also elevate your mental health. Cold exposure triggers a surge of oxygen to the brain and the release of the mood-enhancing hormones beta-endorphin and noradrenaline, which is why you always feel so mentally alert when you step outside on a cold winter morning. This mental boost can help to fight off Seasonal Affective Disorder (SAD) – sometimes referred to as ‘winter depression’ – over the cold and dark months.

New research by Cambridge University even suggests that cold exposure may protect against dementia. And research by Professor Andy Lane, a psychologist at the University of Wolverhampton, has revealed that regular cold exposure can also boost your mental resilience: by overcoming the hardships of cold exposure, you will find it easier to overcome over challenges, whether that is a difficult day at work or an exhausting 100-mile bike ride.

Many of the extraordinary health benefits of cold weather exposure are derived from the simple fact that cold conditions make your body work harder than in normal conditions. But exercising in the cold can also be beneficial for your actual performance times on the bike. Research suggests that cyclists can ride 42% longer in temperatures of 3°C than in warmer 20°C conditions.

Performance data also suggests that marathon runners clock their fastest times when it’s a cooler 3.8-9.9°C. That’s because when we exercise our bodies produce a huge amount of heat – around 20-25 times your resting metabolic heat. So on hot days, your body has to work incredibly hard just to keep cool. But on colder days your body is less stressed, so you can focus better on performance.

Many of the secrets of cold weather training remain a mystery, but it is now clear that getting out on your bike over winter will deliver an avalanche of health benefits, from an increase in your fat-burning metabolism to a boost in your mental health. So don’t be afraid to get outside and cycle this winter – a dose of cold weather exercise is good for you.

by Mark Bailey