Many adults overestimate how intensely they exercise, which means they may not be doing enough to see real health benefits, a new study suggests.

Canadian researchers followed the progress of almost 130 sedentary adults aged between 18 and 64. All were asked to walk or jog on a treadmill at a speed they believed corresponded to light intensity exercise, moderate or vigorous, as described in a physical activity guide.

While most were accurate in relation to light exercise, when it came to moderate or vigorous intensity, ‘they underestimated how hard they should be working to achieve this'.

"Our study findings suggest that the majority of young and middle-aged to old adults underestimate the intensity of physical activity that is required to achieve health benefits. This is worrisome both for personal and public health and wellbeing," commented Prof Jennifer Kuk of York University in Toronto.

Current guidelines state that adults should undertake exercise of moderate to vigorous intensity for 150 minutes per week. This can be broken down into smaller amounts, such as 30 minutes per day, five days a week.

Details of these findings are published in the journal, PLOS ONE.