More than a third of Americans don't take part in any physical activity during their leisure time, according to a recent report from the National Centre for Health Statistics.

Findings showed that only three out of 10 adults exercised on a regular basis, and lack of physical activity contributes to more than 300,000 preventable deaths.

The report, which was based on interviews with 68,000 adults, pointed towards educational attainment as one of the key factors in predicting a habit of regular exercise. The study compared exercise levels of Americans with graduate level education with those with no qualifications, and found that graduates were more than twice as likely to take regular exercise.