Mention 'spa' and one imagines scented candles, soft lighting and the day's tensions being rubbed out of sore, knotted muscles.

However, pampering your body may be more than just a luxury. Some experts believe you can spa your way to good health.

'Muscle tension is your body's way of saying you are stressed. This, in turn, increases your experience of stress,' said Ms Constance Png, a clinical psychologist at Changi General Hospital.

'When you go to a spa or for a massage and your physiological tension is reduced, your body will be more relaxed and you are less likely to experience negative emotions like stress or anxiety,' she added.

A 2005 study published in the International Journal Of Neuroscience found that body massages decreased stress hormone levels and boosted levels of mood-enhancing chemicals like serotonin and dopamine.

If that is news to scientists, the spa industry - and its customers - must have known it for ages.

Estimates of the spa industry's worth here range from $35 million to over $100 million. There are over 750 spa and massage establishments here, said

Ms Nancy Lim, the president of Spa Association Singapore.

German underwriter Soeren Soltysiak, 32, a spa enthusiast who goes for a Thai massage once a month at Ayuthaya - The Royal Thai Spa, said: 'I travel a lot and have a back problem. My body can get very tense, especially after a long flight.

'A massage helps me feel re-invigorated and also to overcome jetlag.'

When a person is stressed, the cerebral cortex in his brain sends alarm signals to the hypothalamus, which is the main switchboard for the stress response.

The hypothalamus then stimulates the sympathetic nervous system, which activates the body's stress response. Stress hormones and steroid hormones are released.

Heart rate, breathing rate, muscle tension, metabolism and blood pressure shoot up. Blood is directed away from the stressed person's hands and feet as well as his digestive system towards the larger muscles in his body, so that he can either fight or run.

Conversely, when the person feels that the perceived threat has been resolved, his brain stops sending alarm signals to the hypothalamus, which, in turn, stops sending panic messages to the nervous system.

His body eventually returns to normal as his heart rate, breathing rate and blood pressure drop.

Mr Danny Ng, a clinical psychologist at Raffles Hospital, said: 'When a person is stressed, it is natural for him to want to seek a form of relaxation that helps normalise and reduce the tension experienced.

'This releases neurotransmitters such as endorphins and adrenaline which will help the person cope.

'Massage has been known to provide this positive relief from stress and pain.'

Besides boosting the levels of pain-relieving endorphins, massages help reduce stress, anxiety and depression by prompting the body to release mood-enhancing chemicals, reduce stress hormones and increase relaxing alpha brain waves.

The restorative effects of massages are also physiological.

Mr Darek Lam, a senior sports physiotherapist at Changi Sports Medicine Centre, said the mechanical effects of massage, specifically sports massage, include improving the body's circulation, helping to stretch muscles and breaking down scar tissue.

This enables the person to recover faster from his workout or injury and improve his flexibility.

While massages relax and re-invigorate the mind and body, body wraps and treatments claim to boost circulation and to get rid of toxins in the body.

Ms Janet Lim, the manager of group public relations for the Spa Esprit Group, said: 'Body wraps detoxify the body and aid in drawing out nasty toxins.

'You will sweat some out during the treatment and pass it out in your urine or faeces later.'

However, doctors Mind Your Body spoke to said that the effects of treatments like body wraps are often temporary and superficial.

Dr Derrick Aw, a consultant at the University Dermatology Clinic at National University Hospital, said: 'Wraps and scrubs mainly exfoliate the skin. They help to remove the outermost layer of dead skin cells, leaving the skin feeling smoother and appearing more radiant. All such effects are temporary.'

Assistant Professor Wong Soon Tee, a specialist in dermatology and internal medicine at Raffles Hospital, said there is no scientific basis in the claim that slimming body wraps help in long-term weight reduction.

He said: 'Wrapping is primarily for two purposes, namely, sweating it out and enhancing the penetration of the substance applied.

'If the ingredient applied is relevant to the patient's condition, it may serve its purpose which may include exfoliation, moisturisation, anti-oxidation and so on.'

To counter the waning of a spa treatment's effects on the body, spa operators advise clients to sign up for a series of treatments.

Ms Elizabeth Wong, director of Renewal Day Spa, said: 'These treatments have a cumulative effect.

'They work in harmony with the body's cycles. For instance, skin has a turnover cycle of between 28 and 40 days, so we recommend a facial once a month to work with the skin's natural cycle.'

The curative properties of massages and other spa treatments may translate to real benefits for the body but injuries can still occur.

Mr Elson Lee, director of The Spa and Wellness Academy and manager of The Spa and Wellness School, said that injuries are often due to the negligence of therapists or due to massages being performed by someone who is not professionally trained.

He said: 'Common injuries are bruises caused by wrong manipulation techniques and fractured bones caused by poor knowledge and inappropriate strength used; people can also have allergic reactions to the massage oil or powder used.'

While there is no regulatory framework for spa practitioners or masseuses, spa owners must have at least 50 per cent or 80 per cent of their workforce certified in recognised massage courses depending on the type of spa they are operating.

This still leaves a pool of uncertified masseuses and spa practitioners in the industry, so customers should ask to view therapists' qualifications before parting with their money.

Spa operators advise spa goers to notify therapists of prior health conditions and to speak up if the massage is uncomfortable or painful.

Pregnant women and older people should opt for gentle massages. Those with heart disease, are on blood thinning medication or have joint and skin disease may not be suitable for certain spa treatments.

A spokesman for De Beaute Spa, whose therapists are all certified, said: 'Spa treatments are non-medical procedures but they promote and help enhance the health of a person's mind and body.'

This article was first published in Mind Your Body, The Straits Times.