The food industry has taken a battering in the two years since the publication of the government's Health White Paper, Choosing Health.

First, the Food Standards Agency settled on traffic lights as the best ­approach to front-of-pack nutritional labelling, even though critics warned they were simplistic and would ­demonise many nutritious foods.

Then there was the government's knee-jerk reaction to Jamie Oliver's TV crusade against the poor quality of school dinners, sparking a draconian ban on sweets and snacks in schools.

Third, the industry still faces the threat of a ban on advertising food and drink to children. And, fourth, it has endured a time-consuming and costly food reformulation programme to cut salt content.

At times, it has seemed as though the government thought changing diets was the be-all-and-end-all of achieving a healthy lifestyle, and in particular halting the obesity epidemic. But there are now signs that, at last, in the great British food fight, ministers are waking up to the importance of exercise as part of the healthy living mix.

The Department of Health has just circulated its draft Healthy Living Social Marketing Strategy, which outlines a campaign that will under­pin the government's efforts to stop the year-on-year rise in obesity among children by 2010. The document, seen by The Grocer, contains a number of proposals designed to reach out to parents of children who may be at risk, as well as parents who are obese themselves.

Many of the suggestions relate to food, but, crucially, the focus of the strategy appears more balanced than others that have previously come from this government. Indeed, about half of the action points contained in the document relate specifically to increasing levels of physical activity.

The draft is the latest of several developments that suggest the government is recognising the common sense that under­pins the calories-in, calories-out philosophy.

In August the Department of Health broadened public health minister Caroline Flint's brief to make her, effectively, minister for fitness. In April, the department launched the Small Change, Big Difference campaign to encourage people to make minor changes to their lifestyles, many of them physical - such as getting off the bus a stop early - to improve their health.

Such initiatives are long overdue. The Chief Medical Officer's advice is for adults to undertake 30 minutes of moderate exercise five days a week, but only 37% of men and 24% of women currently do this, according to official figures. Meanwhile, the Department of Transport's National Travel Survey, published last month, indicates that the number of walking trips per person per year fell by 16% in 2005.

The fact that food has previously borne the brunt of government initiatives, with apparently little emphasis on physical activity, has left some disgruntled.

Dr Richard Cottrell, director of sugar trade body The Sugar Bureau, says: "There needs to be a better balance between addressing diet and lifestyle. There is inadequate emphasis on exercise. It is not helpful to say you can find a 'food solution' to this problem."

Andrew Opie, director of food policy at the BRC, says: "The Social Marketing Strategy looks interesting because it does move the issue more into the arena of physical activity.

"I think in the past the government has been a bit slow to realise the importance of encouraging activity - it has been the Cinderella of the healthy living campaign.

"All the headline grabbing has been about labelling and reformulation of food. The food industry was the obvious target, but there's been an acceptance that it's a much bigger problem. There needs to be a concentration on food, our members accept that, but it's just one part of the equation."

Alison Ward, director of communi­cations at the Biscuit, Cake, Chocolate and Confectionery ­Association, believes the emphasis on food over the past two years has been symptomatic of the belief that governments must be seen to be taking action.

Indeed, that was the thrust of a campaign run by The Grocer in 2004, Junk The Spin, when we expressed fears (with some justification, ultimately) that ministers would beat the food industry with a large stick over health and obesity because big business was a soft target.

Ward says: "Because obesity is chronic and a government has to show progress in a term of office, some solutions will always be seen as easier than others."

Julian Hunt, Ward's counterpart at the Food and Drink Federation, and editor of The Grocer when Junk The Spin was launched, agrees that the food industry was a sitting duck. "It would have been better to have looked at calories-in, calories-out from the outset, because that's the issue," he adds.

But he also sympathises with the government, saying that getting people to take exercise now is harder than it was 20-30 years ago.

"Parents don't want their kids going out to the park, because they're worried about cars and perverts. They'd rather they were at home playing on the X-box. And the adults themselves all drive to work now and have soft jobs."

Hunt is in tune with government thinking on this issue. Part of the Social Marketing Strategy, which is still at the early consultation stage, covers how to "increase children's skills in relation to personal safety" and "decrease parental perceptions of traffic danger to children".

But before the food industry starts to get complacent, the strategy contains plenty on food, including plans to dissuade parents from using food as a reward, and the reformulation drive is set to ­migrate from salt to fat and sugar (The ­Grocer, 14 October, p6).

And the welcome switch in emphasis to exercise doesn't necessarily mean all is now rosy in terms of the how the industry views the government's approach.

For example, Hunt says, there's too much focus on the food people buy at supermarkets and not enough on the food and drink they consume in restaurants and pubs, and the overall contribution these make to an individual's diet. "We're eating out more but that's not part of the debate. And drink is really only considered as a social problem or at the extremes, such as the cost of alcoholism to the NHS, but not in terms of its contribution to calorie intake. Is there a way to fit these pieces of the jigsaw together?"the great traffic light debate

Sainsbury's has been held up as a model for its Wheel of Health scheme by public health minister Caroline Flint and the FSA. It was first in the queue for a government initiative to open GP surgeries in supermarkets. Then came a co-chaired event on child obesity where chief executive Justin King joined Flint on stage.

Sainsbury's is in danger of becoming the government's health stooge - and there are already rumblings of discontent among rivals and manufacturers. One food manufacturer source says there is increasing disquiet over the anti-GDA stance adopted by King. However, the source adds that King appears to have tempered his tone in the past month. "Whether the Department of Health had a word in his ear or it was an internal decision to calm the debate down, it had been starting to get silly," she says.

King, meanwhile, says his agenda has never been about anything other than the customer. "We don't do it for endorsement; we do it because it's right for customers. People like Caroline Flint, other MPs and the FSA have been supportive, which is great. Competition on this issue will move the agenda forward much faster then legislation."

A DH spokeswoman says the government has not singled out Sainsbury's for special treatment. "We have been talking to many organisations. Many of them, Sainsbury's included, were involved in the launch of Small Change, Big Difference earlier this year."

It is clear that King has seen the health debate as a way to differentiate Sainsbury's, especially when the price battle is so keenly focused on Tesco and Asda. Last week, he said that as long as price was "neutralised" and "contained as a competitive tool", Sainsbury's could look to stand itself apart from the pack by competing on these "other" areas (The Grocer, 21 October, p7).

But does this mean the market is being polarised with Sainsbury's pro-traffic light stance at one end and Tesco going with GDAs at the other? One drinks manufacturer, which has opted for front-of-pack GDAs, says: "The last thing any manufacturer wants is to get caught between Sainsbury's and Tesco. We have to make choices based on what is best for our brands; for us, it was GDAs." That, he stresses, has nothing to do with the choice made by Tesco, his biggest customer.

King says it is not a case of choosing sides. "Several suppliers have gone down the multiple traffic light route. There are people on both sides but it's not polarised."

One thing is for certain: brands will be hotly debating whose mast - Tesco or Sainsbury's - to nail their colours to.