Everything that happens to your body when you don’t exercise, according to doctors

1. After the first week

According to Dr Nye, you might not notice too much impact within the first couple of days of stopping exercise. Plus, for some people, a break can be a good boost to their health and well-being, giving a chance for the body to recover. However, he says that some of the health benefits exercising brings begin to disappear after around five days. For one, you may see an initial change in mood. Dr Patel expands on this: 'Exercise triggers the release of endorphins – your brain’s natural mood boosters. Without that regular lift, it’s easier to feel low, anxious or more stressed than usual. In fact, a lack of physical activity is strongly linked to higher rates of depression' (Picture: Getty Images/iStockphoto)

Following this, one of the first signs of exercise reduction is a disruption to your sleep patterns. Particularly a reduction in time spent in deep sleep. Dr Patel notes: 'Regular exercise helps you fall asleep faster and improves the quality of deep sleep. Without it, you might find it harder to drift off, wake more during the night, or feel less rested in the morning' (Picture: Getty Images)

Dr Nye says you will also notice changes to your blood pressure as 'exercising leads to increased heart rate and wider blood vessels.' But, when the body no longer needs the increased blood flow, it will reduce back down. As for your blood sugar, Dr Patel states: 'Physical activity helps regulate insulin and blood sugar levels. When you’re inactive, your body becomes less effective at managing glucose.' This can raise your risk of developing type 2 diabetes – even if you’re not overweight (Picture: Getty Images)

2. After 2 weeks

On the subject of your metabolism slowing down, Dr Patel notes that when you're not moving properly, your body burns fewer calories - even at rest. 'That’s because exercise helps maintain muscle mass, which keeps your metabolism ticking over,' she says. Without it, your body starts to conserve energy, making it easier to gain weight even if your diet hasn’t changed. Dr Nye also states that, two weeks in, the maximum amount of oxygen your body can take in and use will be almost 10% lower. 'You may also find your concentration drops as blood flow to the brain is reduced, as the hippocampus has increased blood flow during exercising' (Picture: Getty Images)

3. 10 weeks

'Muscle fibres reduce in size and the muscle fibres gained during your exercising regime drop by 15%,' says Dr Nye. As muscles shrink down, the expert explains that the space is occupied by fat cells expanding - muscle doesn't turn to fat. You may find your arteries begin to stiffen and narrow, with the changes in fat metabolism increasing your risk of atherosclerosis, says Dr Nye (Picture: Getty Images)

Other parts of your body, including your joints, can stiffen and ache too, explains Dr Patel: 'Movement keeps your joints lubricated and your muscles flexible. Without it, stiffness sets in, your range of motion shrinks, and everyday tasks – from climbing stairs to bending down – can feel more difficult' (Picture: Getty Images)

4. Longer time frames

We've all been told that sedentary lifestyles are one of the leading causes of disability and death worldwide, with increased rates of cancer, cardiovascular disease and metabolic diseases. Dr Nye points to research from the World Health Organisation that suggests regular exercise cuts the risk of any types of cancer by up to 28%, heart disease and stroke by 20%, diabetes by 17%, and dementia by around 30% (Picture: Getty Images)

In terms of heart function, Dr Patel adds that it becomes less efficient. The doctor says: 'The heart is a muscle – and like any muscle, it needs regular work to stay strong. Without exercise, your heart gradually becomes less efficient at pumping blood, which can increase your risk of high blood pressure, heart disease and general fatigue.' Finally, Dr Nye adds that, while there's no hard evidence to say when this risk switches to increased rates, but regular exercise is important to maintain your health and wellbeing (Picture: Getty Images)