Forget the sweaty gym. The road to wellbeing is in the great outdoors, finds Marian Pallister

THE common equation drawn over the past decade is that fitness equals three hourly sessions a week in a steamy aerobics studio or panting it out under the artificial lights of a sweaty gym.

There is no question that these sessions exercise heart and lung, develop stamina, and even add up to a decent body shape. The sum we should be looking at, however, is one which adds up the factors which create wellbeing, rather than simple fitness. For that, we have to add good food, good sleep, and fresh air. The latter is always there for us, but somehow, too many people have got out of the way of using it.

Dr Annette Mutrie, Glasgow University's senior lecturer in bio medical and life sciences, and a guiding force in the Active Commuting Campaign, says research supports the idea that sunshine and sunlight enhance our mood. Even in the park doing nothing, we feel better, while to do something active ''should give us a nice psychological boost''. Outdoor air quality is usually better than the recycled fug of an air-conditioned gym, cutting the risk of breathing in other people's germs, while doing something different in a different environment helps us recover from the daily grind.

''One of the great things about outdoor activity is that it's different from what most of us do the rest of the week,'' Dr Mutrie says, and that ''time out from real life'' can be of great psychological help. A day away having fun with other people is good for self esteem.

Outdoor pursuits accumulate fitness in a different way from the frenetic thrice-weekly indoor workout syndrome. If you go hill walking, explains Dr Mutrie, you spend five to seven hours in the great outdoors. ''The gym offers short, quite intense bursts of activity, while hill walking is low intensity over a period of hours. If you go walking two or three times a month, that accumulates.''

It can, however, be difficult for women on their own to answer the call to feel the sun on their backs rather than the glare of the strip light. The great outdoors, be it the local park or the nearest Munro, coupled with the idea of trying new activities, can be daunting. Glasgow City Council's Women in Sport team has designed a fitness programme for the summer which should help overcome that.

Sharon Burns of Women in Sport explains: ''The idea is to use as much fresh air and have as much fun as possible. Everybody needs the feeling of exhilaration you get from the sun, the fresh air, opening up the lungs and getting a bit of action.''

Windsurfing, sailing, canoeing, running, horse riding, daytime and evening walks, and activity weekends away are all reasonably priced, fully instructed, carefully planned and offer all equipment. ''All you have to do is turn up with enough food and clothing,'' Burns says. By the right clothing, she means simply warm, dry, and waterproof to meet the vagaries of the Scottish climate.

The walks - the cheapest and most effective way of getting out into the fresh air - start in the city's parks, with people getting used to the routes around them. ''Women can be apprehensive about who is lurking behind the next bush,'' says Burns. ''We get people together with a crowd and a leader who shows them the nice aspects of the park, and later they can do the same walk again with confidence.'' At weekends, groups walk further afield, among Scotland's most beautiful scenery. ''We get feedback that it's really changing people's lives.''

The more adventurous can spend two days away, staying in hostel accommodation, with walks at different levels and white-water rafting as an optional extra. Basic-level walks might take women to Strathclyde or Chatelherault parks, across the Erskine Bridge, or around Miln-gavie waterworks. Hillwalking groups able to tackle what Women In Sport grade as level three and four might head to Aberfeldy or Arrochar for two days of walking.

These taster days, and introductory sessions for hang-gliding, caving or rock climbing, can alter a woman's perspective on life or simply get her away from stifling routine. ''We take all the stress and hard work out of organising something like this,'' says Burns. ''We provide the transport, equipment, and instruction; all you have to do is turn up and bring something to eat.''

An activity away day costs around #40, compared with the #55 some commercial outdoor training organisation charge (although of course, these organisations sometimes have the edge when it comes to fitting into busy women's lifestyles). An all-day walk can cost #8. Activities are cheaper for those on benefit, with a Glasgow City Council Passport to Recreation. Weekends cost between #50 and #80.

A cycling away-day costs just #8, while beginners can learn to cycle, find out about the mysteries of cycle maintenance and road craft, and gain confidence in Glasgow's parks during an eight-week course costing just #15, with bikes and helmets provided.

Archery offers an answer for those who prefer a more leisurely pace, with an indoor taster class followed by field archery courses which require skill and stamina. For those looking for ''something different'', there is scuba diving, caving - or the ''midsummer night's madness'' that will ensue when the department takes up to 50 women into Argyll for the summer solstice, to watch the sun go down, climb the Cobbler overnight, and watch the sun rise again. The whole event, based in Arrochar, will raise cash for the Castle Cancer Foundation, a charity for lung cancer, now the biggest killer of women in the west of Scotland.

''We are tying in with the army and mountain safety people,'' says Burns. ''You need to be mad to do it but it will be lots of fun and there'll certainly be lots of fresh air.''

Having fun doesn't mean being careless about personal safety,

however. Following instructions to the letter, wearing the safety equipment provided, and never going off on your own are all part of the outdoor code. So, too, is the use of sun screens. Dr Mutrie says we should never imagine the sun in Scotland isn't strong enough to do damage, and when we take to the great outdoors we should always wear a hat and protect our skin. It makes sense in terms of warding off skin cancers, and anyway, nothing kills high spirits quicker than burned skin.

Burns says: ''For all our outdoor activities you need an average fitness. You shouldn't get out of breath too easily, because any kind of exercise is demanding on your body.''

People go quite happily to a gym during the winter, but give up during the summer months. She suggests: ''Keep that fitness going by doing something aerobic like cycling, walking, climbing, anything which gets the old heart and lungs going and gets you plenty of fresh air. When you spend a day outdoors, you feel the benefits straight away. You feel good about yourself and it gives a boost to how you feel. You feel differently about yourself. Nothing can beat outdoors.''