Sitting in front of a computer all day can rob you of fitness, health and even your life.
A recent study that found men between the age of 25 and 34 scored lower on cardio-respiratory fitness tests than those aged 35 and 39 has underlined what doctors, fitness and sports medicine researchers have long suspected.
Forced inactivity is destroying people's health. Between the ages of 25 and 30, a man is supposed to be at the peak of his physical powers. He's over the energy-sapping growth of adolescence; has filled out as his muscles have grown to build on his fully formed bones; and his heart, lungs and blood circulation have adjusted to his fully matured body. His brain is also better able to control his muscles, bones and joints.
A University of Hong Kong study carried out in the mid-1990s on teenagers found that they had excellent aerobic fitness levels - some of the best in the world - but were already showing poor endurance.
The researchers concluded that this meant the teenagers were genetically excellent, but that the Hong Kong lifestyle - which can leave little time for exercise - meant this was being wasted. Worse - it was being actively destroyed.
Those teenagers are now young adults - about 25 to 30 year olds - and are showing poor aerobic fitness levels.
We've known for at least 10 years that lack of exercise can harm young people's health, but we've done nothing to change it.