There’s no set speed for slow running.
Physiologically, slow running is a pace below the lactate turn point, which is when lactate (an acid produced by the body when it burns carbohydrates for energy) appears in the blood.
“Most people don’t have access to that kind of data, so we use talking as a threshold point,” Professor Gordon says.
“Slow running is that intensity when you can hold a conversation but you also feel like you’re doing a workout – it’s a fine balance,” explains Gordon. “For some people, that may just be a slow jog because of their level of physical fitness, but for highly trained athletes it’s a fair pace.” If talking starts to become tricky, it’s a sign to slow down.
The five health benefits of slow running
1. Improves heart health
The heart drives two things – the rapidity of its beat (our heart rate) and the volume of blood that is forced out with each beat (our stroke volume), explains Gordon.
While our heart rate goes up in line with how hard we’re exercising, stroke volume will be at (or close to) its peak when we’re exercising in zone two, such as slow running.
This may not feel like strenuous exercise but it improves stroke volume, which means more blood can be ejected for every beat of the heart. This blood transports oxygen to fuel your muscles, meaning you can exercise for longer. It will also help lower your resting heart rate.
“To fundamentally improve the health of the heart, and therefore improve cardiovascular health, you don’t really need to be training higher than 60 per cent, which puts people slap bang in the middle of this slow running zone,” explains Professor Gordon.
As slow running is a form of moderate exercise, it also improves the elasticity in the blood vessels, which reduces blood pressure and lowers the long-term risk of stroke and heart disease, explains Dr Rebecca Robinson, a sport and exercise medicine consultant. Two significant health boosts for the price of a light jog.
2. Builds endurance
Slow running helps to develop the foundations of our cardiorespiratory fitness and ultimately supports us to run further and faster, explains Gordon. For this reason, elite runners spend around 80% of their training at this zone two pace, he says.
This effect is down to changes that slow running triggers throughout the body.
“Slower exercise increases the density of mitochondria in all of our cells (the energy factories) and increases the concentration of myoglobin (a protein in muscles that helps carry oxygen),” explains Robinson.
“These processes allow the body to handle oxygen more efficiently which can ultimately support the level at which we can run and train,” she says.
Running slowly also strengthens the heart, lungs and muscles, including helping the body to develop more type one muscle fibres, which are needed to increase endurance and delay the onset of fatigue, Robinson says. “These adaptations enable the body to operate more efficiently,” she adds.
3. Reduces risk of injury and illness
As running speed increases, so does the risk of injury. “You’re putting the muscles under greater stress and musculoskeletal injuries become more likely,” Professor Gordon explains.
Spending more time running slowly blunts this risk. It exerts less force through the muscles, tendons and joints, while helping to prime the body for faster running, Robinson explains. Adding in some gym-based strength training offers extra protection against injury, she says.
Gentle exercise like slow running also stimulates the immune system, reducing the risk of becoming unwell. In contrast, high-intensity exercise such as faster running “can increase stress on the body’s cardiovascular system and hormonal response in such a way that can slightly blunt the immune response”, Robinson explains.
“Higher intensity training isn’t harmful but alone it might not confer quite as many protective benefits in such a sustainable way,” she adds.
4. Burns more fat
While a fast run and other forms of high-intensity exercise burn carbohydrates for energy, slow running causes the body to burn stored fat, Gordon explains.
“Fat burning can help regulate our metabolism and manage weight and insulin levels,” Robinson says. “So using the lower zones to burn fat can work.”
However, this doesn’t necessarily mean that slow running is better than fast running for weight loss. “Although you’re burning less fat during high-intensity exercise, the recovery time is far longer than that of a slow run,” Gordon says. During this recovery, the body burns stored fat to lower temperature and restore carbohydrates levels, he says.
This means that the overall effect between slow and fast running on weight is much less clear cut, he says.
5. Boosts your mental health
Exercise is known to improve our mental health. It reduces stress hormones and triggers the body to release mood-boosting endorphins.
“Slow exercise can bring all of the above benefits but without the stress of our hardest workouts,” says Robinson. It encourages us to be more mindful of our feelings as well as nature around us, if exercising outdoors, she says.
“As we can exercise at a conversational pace, it can be an important time to connect with the friends we work out with – helping ours and their mental wellbeing,” Robinson adds.
FAQs
How far do I have to slow run to achieve the benefits?
There isn’t a set distance you need to slow run to see the benefits, though the low intensity means you’re able to run for a longer period of time. One study found that slow running for five to 10 minutes a day is enough to see cardiovascular benefits.
Is slow running good for weight loss?
Yes, slow running causes the body to burn stored fat and regulates insulin levels. So it does support weight loss, when combined with a diet plan and muscle training.
Is slow running the same as brisk walking?
No, slow running and brisk walking are not the same. Slow running is higher-impact so burns calories at a faster rate, even if the speed is similar.
