A report expected in two weeks from the national Physical Activity Task Force will paint a dismal picture: Scots are inactive, unfit and overweight. The health of two-thirds of adults is impaired by physical inactivity, which leads to disease, disability and poor mental health. The rot sets in before children leave school and is the most common factor of heart disease.
But there is a bright side. Activity does not need to be strenuous to have a major impact on health and well-being, and the greatest benefits will be gained by persuading the unfit - nearly three-quarters of females and 60 per cent of males over 16 in Scotland - to become moderately active. Running marathons or playing rugby are neither necessary nor desirable for all of us and it is quite possible to keep fit by washing the car and walking to the shops.
The minimum recommended levels of physical activity for good health are 30 minutes of moderate activity on most days of the week for adults and one hour for children. The latter should include some weight-bearing activities, such as jumping or skipping, to help build strong bones.
The national Physical Activity Task Force, set up by the Scottish Executive with invited members from a variety of sporting, educational and health backgrounds, was given the challenging remit in June 2001 of devising a strategy for improving the nation's health by raising the levels of physical activity in all age groups.
Mary Allison, the physical activity research specialist at the Health Education Board for Scotland who is rumoured to become Scotland's first physical activity tsar next month, says: "Children are still very active at primary school. They love running, jumping, skipping and getting out to play. But from about the age of nine onwards physical activity declines.
"For teenage girls it declines dramatically, from two-thirds of girls active at levels appropriate for health at the age of 11, to only one third by the age of 14. For boys there is also a decline that continues throughout their lives, but it's more gradual."
What these bare statistics demonstrate, she says, is that young children are spontaneously active but not in ways that support them with lifelong physical activity.
"One of the most important determinants of an active life is what we call self-efficacy, the extent that you feel confident to be active. Many adults don't have that. So we need to look at how we can start building that foundation of confidence when people are still young."
Research has shown that two factors contribute to the decline in physical activity with age, she explains; one is relevant to all youngsters and one is specific to girls. Younger children are not overly concerned about technical competence but as they grow older they become more conscious of their performance, so a lot of teenagers drop out because they think they are not good enough. In addition, since being active is identified with playing sports, large numbers of teenage girls drop out because they don't want to be regarded as sporty.
"We have to challenge that identification of physical activity with sport," says Ms Allison.
"There are a couple of even more basic problems. People have to accept first that physical activity is important to health. Currently only a third of Scottish adults know how much activity they need.
"Then, when we start to promote activities and sell the idea, we have to address the issue that there often aren't the support structures around to help people become and remain active."
Evidence shows that a strong foundation for a healthy lifestyle has three components: the right attitude to activity, the knowledge of why it is important and the skills needed to take part.
"We have to start as early as possible, even before children go to school," says Ms Allison. "More support and guidance are needed for parents and teachers. Parents often seek advice about feeding their kids but very few seek advice about physical activity.
"It's a complex challenge and it will take people in education, in the community and in health all working together to make sure it becomes developmental, from pre-school, to primary and secondary and beyond. There currently isn't much evidence that a child born in Scotland today will get that continuity and progression.
"What we need is for physical activity to become an integrated part of service provision for young people. The Physical Activity Task Force should set a platform for making that happen, if ministers respond positively.
"What we need is for physical activity to become part of the mainstream."
National Physical Activity Task Force, www.show.scot.nhs.uksehdpatf