The most significant health benefits come from minimal exercise - with more strenuous regimes providing fewer or no gains, a study has found.

In an article published in the Journal of the American Medical Association (JAMA), Dr Thijs Eijsvogels and Dr Paul Thompson compared the effects of varying amounts of moderate (cycling or fast-walking) and vigorous exercise (running or rowing) on cardiovascular disease and mortality rates.

The ‘lowest effective dose` - the smallest amount of exercise that can yield health benefits - was found to be 15 minutes of moderate exercise daily, amounting to 105 minutes weekly.

These claims contradict the NHS guidelines for adults, which recommend 150 minutes of moderate activity per week.

The difference was equally stark for vigorous activity, where the studies pointed to between 35 and 70 minutes weekly as optimal, against the recommended 75 by the NHS and Harvard University.

The JAMA article also cast doubt on the additional benefits of higher levels of exercise, with its research pointing to a tapering off and even a decrease in cardiovascular health and life-expectancy.

A Copenhagen City heart study was used to suggest that while moderate increases in the amount of exercise did result in mortality benefits, physical activity beyond a certain point, seen here to be more than 240 minutes per week, yielded no additional health advantages.

However, the existence of an upper limit to exercise benefits will be irrelevant to many Brits, 40% of whom admitted to doing no moderate exercise at all in a 2015 study by the British Heart Foundation, confirming what some have labelled an "inactivity pandemic".