Physical activity

The association between physical activity and cardiovascular disease mortality (and all-cause mortality) is well established.¹

Studies show that being physically active can reduce the risk of developing CVD by 35%.² The self-reported activity data from older studies has since been confirmed with modern device-based measures that show even low levels of light intensity activity lowers the risk of mortality.³

Just like exercising any other muscle, regular moderate physical activity has been shown to strengthen the heart muscle. This enables it to pump more efficiently, which in turn leads to a lower resting heart rate and lower blood pressure. Regular activity also improves many other risk factors for cardiovascular disease, including lowering cholesterol, regulating blood sugar levels, reducing general inflammation, and maintaining a healthy weight.⁴

In addition to cardiovascular health benefits, these effects also improve overall health, including a reduced risk of developing type 2 diabetes, enhanced sleep quality, reduced anxiety and depression, improved cognition, and a lower risk of cognitive impairment, such as Alzheimer’s disease, as well as lower risks of many cancers.⁵

There is some evidence that physical activity reduces weight gain, and is associated with healthier levels of adiposity.⁶ However, the data for this is highly variable, indicating other factors (such as sedentary behaviours, diet, hormonal balance, etc.) are also important.

What can you do to lower your risk?

The World Health Organization recommends that adults aged 18-64 (and 65+) should do at least 150 minutes of moderate intensity aerobic physical activity throughout the week, or at least 75 minutes of vigorous intensity aerobic physical activity, or an equivalent combination.⁵

These guidelines are relevant to almost all adults, irrespective of age, sex, or ethnicity, and includes people with many chronic health conditions. However, persons with chronic health conditions (such as cardiac conditions) may need to take extra precautions and should seek medical advice before gradually working towards the recommended levels of physical activity for their age group.⁵

What counts as moderate activity will be different for each of us (and can vary from day to day), but the “talk-test” is an easy way to check you are working at moderate intensity.

The NHS gives the following guidance⁷:

• Moderate activity will make you breathe faster, but you should be able to talk throughout the activity i.e. the “talk-test”.
• Vigorous intensity activity will make you breathe hard and fast, and you have to pause for breath every few words.

Examples of moderate activities include: brisk walking, cycling, dancing, playing sports or exercise, some household chores, mowing the lawn, and some types of work.

Examples of vigorous activities include: running, swimming, fast cycling, aerobics, fast-paced sports such as football.

Not everyone will be able to carry out these activities, so the BHF and NHS runs through chair-based exercises which can help keep us all active.

Previously, the recommendations were that activity had to be in sessions of 10 minutes or more, but the WHO guidelines changed in 2019, removing the 10-minute criterion, reflecting newer evidence which suggested that there is no minimum amount of physical activity required to achieve some health benefits (doing some physical activity is better than doing none). For additional general health benefits, adults should also do muscle-strengthening activities at least twice a week.

Further health benefits can be gained if adults increase their moderate-intensity aerobic physical activity to 300 minutes per week or engage in 150 minutes of vigorous-intensity aerobic physical activity per week, or an equivalent combination. It is thought that there are very few risks associated with engaging in up to 300 minutes of moderate activity per week, with the primary risks being musculoskeletal injuries.⁵

Sedentary behaviour

The WHO defines sedentary behaviour as time spent sitting or lying with low energy expenditure, while awake. This may be at home, at work/education, in the community or on transport.⁵

Sedentary behaviour is a separate risk factor from physical inactivity. A person could meet the physical activity recommendations of 150 minutes of moderate activity per week and yet still be sedentary much of the rest of the time. A meta-analysis of over 1 million participants showed that sedentary behaviour is associated with higher levels of cardiovascular disease mortality (and all-cause mortality), independent of physical activity.⁸

Those who sit for more than 8 hours per day have a 32% higher risk of CVD mortality than those who sit for <4 hours per day.⁹ Only adults who are the most physically active (60-75 minutes per day) are able to compensate for sitting for more than 8 hours per day.⁹ Human’s are supposed to move. Reducing sedentary behaviour has similar benefits to physical activity, not only directly affecting the cardiovascular system but also helping to regular blood sugar levels and helping to maintain a healthy weight.

What can you do to lower your risk?

The WHO recommends that all adults should limit the amount of time spent being sedentary, and replace sedentary time with physical activity of any intensity (including light intensity).⁵ The BHF has ideas for being less sedentary both at home and at work. As well as breaking up sedentary time by trying to get up for 5 minutes every half hour, the BHF suggest standing up when talking on the phone (at home or work), walking across the office to speak to colleagues rather than sending an email, popping to the kitchen every time the TV adverts are on, dance whilst the kettle boils, walk on the spot or stand on one leg to brush your teeth.¹⁰

The seated exercises suggested by the BHF and NHS are great options while watching TV or to break up time at your desk.

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