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7 reasons to exercise

Megan Widdows
Written by

Megan Widdows

Medically reviewed by

Fiona Moncrieff

9 min read
Last updated May 2024

Sometimes reminding ourselves of the positive impact that exercise has on our bodies is the motivation we need to move more. We all know that exercise is good for us, but we might not always consider the various specific benefits

This guide digs deep into the benefits of exercise from heart health to better sleep and improved mental health. 

We’re all living increasingly busy lives, and exercise often feels like something we just don’t have time for. In fact, more than 1 in 3 women and 1 in 4 men aren’t doing enough exercise to stay healthy

However, exercise has a positive effect on almost every part of our bodies. It goes far beyond helping us to lose or maintain weight. It can be instrumental in helping us to live a long, healthy, and happy life. 

It’s important to note that exercise doesn’t just mean going for a run or lifting weights. There’s so much variety in the types of activities that count as exercise that there’s something for everyone! Finding a form of exercise that you enjoy is key to ensuring you can stick at it, and see the long-term benefits. 

From our research, here’s our top seven benefits of exercise:

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1. Reduced risk of death

Perhaps the most significant benefit of regular exercise is that it can reduce our risk of early death.

Research suggests that men and women who are physically active have a 20-35% lower chance of dying from any cause than people who are inactive. This is likely due to the lower rates of health conditions such as heart disease and cancer. 

Although we still don’t have a full understanding of why this may be, it could be that taking part in regular exercise also means that we’re more likely to have other healthy habits such as eating well.

Exercise may also have direct knock-on effects, such as helping to manage our stress levels, improve our sleep, and reduce emotional eating. 

Inactive middle-aged women who exercise for less than one hour each week have a 52% higher chance of dying from any cause than their more active peers. They’re also twice as likely to die of heart disease and 29% more likely to die from cancer. 

While those figures seem disheartening, a weekly dose of 150 minutes of moderate activity (walking, ballroom dancing, gardening) or 75 minutes of vigorous exercise (cycling, running, swimming) could be enough to cut the risk of premature death through heart disease by 40%. For context, that’s a similar amount to taking the cholesterol-lowering drug statins. 

Even a modest increase in physical activity, roughly equivalent to a 20-minute brisk walk each day, may lower the overall risk of death by 20%

Key points:

  • Exercising regularly could reduce our overall risk of death by upto 35%
  • Small increases in activity levels can have significant positive effects on our health


2. Lower risk of heart disease

As we mentioned, regular exercise lowers our risk of dying from any cause. One of the main ways it potentially does this is by reducing our risk of developing heart disease. 

Heart disease is the leading cause of death worldwide, responsible for 17.9 million deaths in 2020. Risk factors include being overweight, smoking, having high cholesterol, high blood pressure, diabetes, or having a sedentary (inactive) lifestyle. 

There has been lots of research into the link between heart disease and exercise, with studies finding a strong link. The evidence strongly suggests that the more active we are, the lower our risk of developing heart disease

There are lots of different mechanisms by which exercise can help reduce our risk of heart disease. One of these is that exercise induces the production of nitric oxide which helps keep our blood vessel linings healthy

We need a healthy blood vessel lining to prevent the build up of fatty deposits in our artery walls that can go on to cause heart disease. The starting point for these fatty deposits, known as atherosclerotic plaques, is cholesterol. 

However, cholesterol can only enter the linings of our arteries if there is damage to the artery wall. Amongst other things, by increasing our production of nitric oxide which protects blood vessel linings, exercise lowers our risk of heart disease. 

Moreover, as we exercise, blood flow increases and our smaller blood vessels dilate to help get oxygen to our muscles. This reduces the likelihood of smaller vessels becoming blocked that could cause a heart attack or stroke. 

Key points: 

  • A lack of exercise is a major risk factor for heart disease
  • The more active we are, the lower our risk of heart disease 


3. Lower risk of type 2 diabetes

Type 2 diabetes is a chronic disease that’s characterised by insulin resistance, high blood sugars, and often obesity. Having low fitness levels can increase the risk of developing type 2 diabetes

One study found that women who did 30 minutes of brisk walking, or equivalent exercise, 5 or 6 days a week have a 48% lower risk of developing type 2 diabetes

During exercise, our muscles contract more frequently. These muscle contractions require our muscle cells to increase the amount of glucose they take up from the bloodstream. Insulin is a hormone that enables cells to be able to take up glucose from our blood, causing blood sugar levels to decrease. 

Exercise increases how responsive our cells are to insulin, so we need smaller amounts of insulin to maintain stable blood sugar levels, reducing our risk of type 2 diabetes.  

On top of this, a lack of physical activity over time has been linked to higher fasting insulin levels. High levels of circulating insulin contribute towards insulin resistance, a key component of type 2 diabetes. 

People with type 2 diabetes no longer respond to insulin in the same way, causing blood sugar levels to rise. Using exercise as a tool to lower fasting insulin levels and lower insulin resistance helps to reduce your risk of developing type 2 diabetes. 

Research suggests that the type of exercise isn’t important, with more moderate and vigorous-intensity exercise, and aerobic exercise and resistance training, both increasing insulin sensitivity

Key points:

  • Exercise typically lowers blood sugar levels and increases insulin sensitivity 
  • Insulin resistance (low insulin sensitivity) is characteristic of type 2 diabetes
  • Both moderate and vigorous exercise have been shown to increase insulin sensitivity and our risk of type 2 diabetes


4. Better sleep

Getting a good night’s sleep is very important for our health, happiness, and wellbeing. Lack of sleep is known to have knock-on effects on many aspects of our health, including our diet and ability to make healthy choices, the functioning of our immune system, and our mental health. 

Anecdotal evidence suggests that exercising during the day helps us sleep better at night because our muscles are tired. Stronger evidence comes from a meta-analysis that found that when people exercised 4-8 hours before bedtime, they fell asleep faster than people who didn’t exercise or people who exercised less or more than 4 hours before bed. 

People who exercised at any time in the day also spent significantly longer in the second stage of sleep, which is involved in memory consolidation and learning. 

However, research also shows that people who didn’t sleep well the night before are less likely to exercise the next day, due to low energy levels, which could help to create a vicious cycle of poor sleep and lack of exercise

Even when you’re feeling tired, try to fit in some physical activity even if it’s less intense, such as brisk walking or a 15-minute yoga practice, and you might sleep better at night! 

Key points:

  • A lack of sleep can have many knock-on effects such as making us more hungry and less likely to exercise
  • People who exercised between 4-8 hours before bed were found to fall asleep faster than those who didn’t exercise, or who exercised closer to bedtime


5. Lower risk of Alzheimer’s disease

One of the lesser-known benefits of exercise is that it can protect against cognitive decline, including Alzheimer’s disease, as we age. A randomised trial found that three sessions of moderate-intensity aerobic exercise (such as walking, cycling, or jogging) increased the size of the hippocampus by 2%

The hippocampus is a part of the brain that is involved in learning, emotions, and memory formation. As we age beyond 70, research suggests that our hippocampus shrinks by around 1.5% each year. So it seems that exercise may improve cognitive function and slow the natural progression of hippocampus shrinkage and potentially the onset of Alzheimer’s. 

Want to find out more? We have a complete guide exploring the link between exercise and cognitive decline. 

Key points:

  • Exercise can increase the size of our hippocampus, an area of the brain associated with memory 
  • As we age, our hippocampus naturally shrinks 
  • Exercise may mitigate the shrinking of our hippocampus, reducing our risk of Alzheimer’s


6. Increased happiness

Exercise is one of the most powerful tools we can use to boost our mood. A recent review found that there was a strong link between exercise and happiness and that doing exercise for just 10 minutes can result in increased levels of happiness.

Compared to being sedentary, one study found that our odds of being happy were 20% higher even if the amount of exercise we’re doing is still considered insufficient. The research suggests that our chances of happiness increase with the amount of exercise we do, with very active people being 50% more likely to be happy than sedentary people. 

The science behind exercise and happiness isn’t fully understood but is thought to be linked to the release of mood-boosting endorphins. So, next time you’re feeling less than happy, try exercising to quickly boost your mood. 

Unsurprising due to its link to increased happiness, exercise has also been linked to better mental health. One study of people in the United States found that people who engaged in regular physical activity were 40% less likely to meet the criteria to be diagnosed with major depression and 50% less likely to be diagnosed with generalised anxiety disorder.  

Research also suggests that exercise may be a helpful tool for people with depression with similar results to psychological therapy or pharmacological treatment. 

More research is needed to fully understand the impact of exercise on mental health, but the potential benefits are already apparent. 

Key points:

  • Research suggests that exercise is a powerful tool for increasing happiness
  • As little as 10 minutes of exercise can make us feel happier
  • Regular exercise is also linked to a lower risk of developing depression or anxiety


7. Weight loss

Weight loss may be the first thing that comes to mind when thinking about the benefits of exercise. Indeed, exercise can mildly boost our metabolism or the number of calories we burn each day, which can contribute to weight loss, alongside a healthy lifestyle and diet.  

However, studies have shown that people who use exercise alone, without changing their diet, experience minimal weight loss. For successful weight loss, it seems that exercise needs to be combined with a healthy diet. 

Similarly, while all exercise has been shown to be beneficial in improving health, not all exercise is equal when it comes to weight loss. A clinical trial compared the effect of high-intensity interval training versus steady exercise on weight over 15 weeks. People taking part in the HIIT exercise program lost significantly more weight than those who did steady exercise or no exercise

However, beyond weight loss, exercise offers many physical and mental health benefits. 

Any exercise we do can positively impact our mental wellbeing which has knock-on effects of weight loss. For example, when we sleep better we have fewer cravings and can make healthier choices the following day. 

Most importantly, exercise is something that should be enjoyed, not endured! Find an activity that you enjoy, and it’ll be much easier to exercise regularly. 

Key points:

  • Exercise can be beneficial for weight loss but diet is another important factor
  • HIIT exercises have been shown to be the most effective for weight loss


Take home message

  • Exercise is one of the most powerful tools we have for improving our health and happiness
  • Regular exercise can reduce your risk of developing chronic diseases such as heart disease, type 2 diabetes, and Alzheimer’s disease
  • Exercise can increase happiness and research suggests it may lower your risk of depression and anxiety 
  • Exercise can help us to lose weight if we have weight to lose
  • You don’t need to be doing vigorous exercise for hours each day to feel the benefits.
  • Modest increases in activity levels have been shown to have significant positive results


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