How much exercise is good for me? What are the benefits of moderate intensity activity - and how much per day

Increasing your physical activity is good for your health, but the benefits are greater when more of it is of at least moderate intensity, a new study has suggested.

But what did the study find and how much intense exercise should you be doing? Here’s what you need to know.

How much exercise should we be doing?

Researchers from Cambridge University and Leicester University analysed data from more than 88,000 middle-aged adults who wore a device on their wrist to measure their physical activity. Participants wore the accelerometer on their dominant wrist for seven consecutive days as part of the UK Biobank study.

Researchers then calculated the participants’ volume of activity, as well as the percentage of it that was of moderate intensity such as a brisk walk, and of vigorous intensity such as running. They had recorded the number of cardiovascular events, including heart disease, among study participants over an average follow-up period of 6.8 years.

According to the research, higher total physical activity volume was strongly associated with a decrease in the risk of cardiovascular disease. This physical activity being moderate to vigorous was also associated with a further reduction in cardiovascular risk.

Cardiovascular disease rates were 14% lower when moderate to vigorous physical activity accounted for 20% rather than 10% of the overall physical activity energy expenditure, even in those who otherwise had low levels of activity.

Overall, the lowest cardiovascular disease rates were observed among participants who undertook higher levels of physical activity and a higher proportion of at least moderate exercise.

However, when overall volume of physical activity increased but the proportion of at least moderate intensity activity remained the same, the authors observed little effect on cardiovascular disease rate.

Professor Tom Yates of Leicester University, one of the paper’s senior authors, said: “Our analysis of data from UK Biobank confirms that increasing the total amount of physical activity can lower the risk of suffering a heart attack or stroke, but we also found that achieving the same overall amount of physical activity through higher intensity activity has a substantial additional benefit.

“Our findings support simple behaviour-change messages that ‘every move counts’ to encourage people to increase their overall physical activity, and if possible to do so by incorporating more moderately intense activities.

“This could be as simple as converting a leisurely stroll into a brisk walk, but a variety of approaches should encourage and help individuals to find whatever is most practical or enjoyable for them.”

What does the NHS say about exercise?

The NHS says adults should do some type of physical activity every day. “Exercise just once or twice a week can reduce the risk of heart disease or stroke,” the website added.

However, you should speak to your GP first if you have not exercised for some time, or if you have medical conditions or concerns. Make sure your activity and its intensity are appropriate for your fitness.

Adults should aim to:

• do strengthening activities that work all the major muscle groups (legs, hips, back, abdomen, chest, shoulders and arms) on at least 2 days a week
• do at least 150 minutes of moderate intensity activity a week or 75 minutes of vigorous intensity activity a week
• spread exercise evenly over 4 to 5 days a week, or every day
• reduce time spent sitting or lying down and break up long periods of not moving with some activity

You can also achieve your weekly activity target with:

• several short sessions of very vigorous intensity activity
• a mix of moderate, vigorous and very vigorous intensity activity

These guidelines are also suitable for disabled adults, pregnant women and new mothers.