As the chill of winter creeps in, the temptation to stay inside is real. But if you’re happy to brave the outdoors, studies show that continuing to keep fit outside could be beneficial for both body and mind.
1. General health
There are several studies linking exercising in green spaces to lower risks of heart disease, obesity, asthma and diabetes. Exercising outdoors has also been shown to boost your mental health and overall happiness.
A study in June 2019 found that those who spent at least 2 hours a week in nature were 20% more likely to report overall satisfaction with their lives than those who spent no time outdoors at all.
The benefits to physical health were even greater, with 60% of those who spent more than 2 weekly hours outdoors reporting being in good health compared with those staying indoors. What’s more, it didn’t matter whether this outdoor experience was taken in one long session or broken up into smaller sessions.
Inflammation can be reduced with local exposure to cold – just think of the effect of putting ice packs onto sprains.
But there is some evidence to show that cold temperatures might suppress pain too. Finnish researchers discovered that women who plunged into cold water (just above freezing) for 20 seconds a day for 3 months had higher levels of norepinephrine levels in their blood. This is a chemical in the nervous system that – among other things – may help suppress pain.
Exercise helps support immunity. As we head into winter during the Covid-19 pandemic – with many unable to visit gyms or sports clubs – experts are encouraging people to keep fit.
The World Health Organization (WHO) suggests adults do at least 150 minutes of moderate-intensity physical activity throughout the week or at least 75 minutes of vigorous physical activity.
Winter workouts also increase exposure to natural light, which itself may help to ward off seasonal affective disorder (SAD) – a type of depression that some people experience during the winter months.
Sunlight exposure stimulates the hypothalamus, a part of the brain that helps control your circadian rhythm which is the body’s 24-hour internal ‘clock’. Lack of light can disrupt this clock, causing your brain to produce too much of the sleep hormone melatonin and to release less of the ‘feel-good’ hormones such as serotonin. The result is that you feel low and may also experience sleeping difficulties.
A lunchtime walk in winter on sunny days could help begin to counteract this effect. But there is no evidence about the optimum amount of sunlight you need to be exposed to for your mood to be enhanced. Length of time will vary due to factors such as variation in skin colour and how close you are to the equator.
Cold temperatures may make your body burn more calories through a process called thermogenesis, in which your body generates its own heat to keep you warm. One study found that people who hiked in cold temperatures of -9ºC to -5ºC burned 34% more calories than people who hiked in temperatures of 12ºC. Of course, many factors influence how many calories you burn and being active is important all year around.
3 precautions to keep you well while exercising outdoors
1. Layer up
Cold air temperatures can cause vasoconstriction – narrowing of the blood vessels – which can lead to circulation problems and an increase in blood pressure. It’s a good idea to wear layers of clothing, starting with a thin layer of synthetic material such as polypropylene, which draws sweat away from the body. Avoid cotton, which absorbs sweat and can make you colder. Then add a layer of fleece or wool for insulation and top with a waterproof, breathable layer.
2. Use sunscreen
Apply sunscreen of at least SPF 30 and be careful not to underestimate the amount of UV radiation passing through clouds. Many surfaces reflect UV radiation and add to the overall UV levels you experience. Fresh snow, for example, is a particularly good reflector and almost doubles a person’s UV exposure. Even on cloudy days UV radiation can reach the Earth and cause sun damage, so it’s still important to apply SPF on an overcast day.
3. Stay hydrated
Several studies show that you are more likely to get dehydrated in winter. One piece of research found that exposure to cold reduced the signals between the brain and the kidneys to conserve fluid. The thirst sensation was also reduced. Make sure you drink water regularly when you’re exercising outside, even when you’re not feeling thirsty.
Reviewed by Dr Rhianna McClymont, Lead GP at Livi