More than a billion adults around the world are at risk of serious disease through lack of exercise, according to research by the World Health Organisation.
Investigators found that in 2016 more than a quarter of the global population - 1.4 billion people - were insufficiently active.
The data, which is published in the Lancet Global Health journal, warns very little progress has been made in reducing levels of inactivity worldwide.
The research estimates that more than a quarter of people worldwide are not doing enough physical exercise.
In Ireland, almost four out of 10 women are not active enough, while the same is true for three in 10 men.
That is roughly similiar to other high-income countries where the proportion of inactive people had risen from 32% in 2001 to 37% in 2016, while in low-income countries it had remained stable at 16%.
Those who were classed as inactive did less than 150 minutes of moderate exercise, or 75 minutes at a vigorous intensity, a week.
Countries driving the upwards trend included Germany, New Zealand and the US.
Countries with the worst physical activity record included Kuwait, American Samoa, a US territory in the South Pacific, Saudi Arabia and Iraq. In each of these countries, more than half the adult population was insufficiently active.
The Lancet says the health benefits of physical activity are well established and include a lower risk of heart disease and cancer.
It' i warning that policies to increase activity need to be prioritised and scaled up urgently.
The research conducted by the World Health Organisation shows there was little progress in improving physical activity levels between 2001 and 2016.
If current trends continue, the global target of reducing sedentary lifestyle by 10% by 2025 will not be met, said the scientists.
Study leader Dr Regina Guthold, from the WHO in Switzerland, said: "Unlike other major global health risks, levels of insufficient physical activity are not falling worldwide, on average, and over a quarter of all adults are not reaching the recommended levels of physical activity for good health."
The study was based on self-reported activity levels both at work and at home and during travel and leisure time.
Researchers analysed information from 1.9 million men and women who participated in 358 population surveys.
