Ancient Greek scholars realised long ago that physical activity was a requirement for good health. Hippocrates proposed that “eating alone will not keep a man well – he must also take exercise”, while Galen later noted that “the body is in need of motion, exercise is healthy and rest morbid.”
Roughly 2,000 years on, the empirical evidence for physical activity as an essential part of a healthy lifestyle is overwhelming. Across many different types of studies and for various health-related outcomes the message is clear and consistent. Physical activity has a demonstrably important effect on the risk of disease and mortality outcomes.
So you might expect that by now we would also be able to give people clear advice on exactly how much physical exercise is “enough”.