In one of the Centre on Behavioural Health's more recent studies, researchers found that qigong improved the physical and mental fatigue levels of patients suffering from chronic fatigue syndrome and depression, and have used the results of that study as the basis for the new study.

Qigong involves rhythmic breathing co-ordinated with slow repetitive movement, a calm state of mind, and visualisation of guiding the qi through the body. Combined with healthy diet and habits, qigong can help patients achieve an improved state of well-being.

Professor Jonathan Sham Shun-tong, honorary clinical professor at HKU's clinical oncology department and one of the experts in the 'Walking Hand in Hand' study, suggests the use of qigong to about one-third of his patients. Some 80 per cent to 90 per cent of his patients use TCM, as many are troubled by the side effects of Western medicines.

Sham is reluctant to make any grand claims, however. 'It is not possible to discern with 100 per cent certainty the effect of qigong from the effects of various treatment combinations, but the general feeling is that these patients have better quality of life and more confidence in their own health and tumour control.'

Dr Yuen Lai-ping, chairwoman of the International Association for Health and Yangsheng, will lead the qigong classes for the study. She has designed Wuxing pinghenggong, a sequence of 10 movements that is said to suit the needs of modern life.

Yuen was separated from her family as a young girl and sent to a Taoist monastery in Shaanxi to live for a few years. While there, she learned from the priests who practised qigong every day. 'I would wake up at 5am and walk with the priests to find herbs and then meditate.'

After she graduated from school, she attended the Beijing University of Chinese Medicine and has been practising Chinese medicine in Hong Kong for more than 15 years. She believes that the internal nourishment of qigong helps people who suffer from chronic conditions such as cancer, stroke, depression and immunological disorders.

Last year, Yuen oversaw qigong treatment of 72 women, aged 23 to 52, who reported symptoms of chronic fatigue in a study facilitated by the Centre on Behavioural Health. Professor Cecilia Chan, associate dean of HKU's faculty of social sciences, led the research and found that, compared with the control group, 'qigong learners experienced a reduction in physical and mental fatigue, and the effect may have lasted for three months after the class'.

Ng Lai-ling, a nurse in her 40s, suffered from chronic fatigue for five years until she begin taking qigong with Yuen. 'It was the only way to save myself because I tried everything. I was in a severe state. I was exhausted all the time.'

After a month of qigong study classes three to four times a week, Ng felt more energetic and was sleeping better. 'Now, I can manage the shifts, and I feel in a state of well-being. I even taught my 80-year-old mother qigong so we can do it together,' she says.

For Yann Cheung, 39, who suffers from chronic pain and depression, matters were more desperate. 'I couldn't leave the house or even go to the bathroom alone. The chronic pain and fatigue were so bad, I wanted to kill myself.'

After nearly one year of qigong with Yuen, Cheung has stopped nearly all her pain medication and is sleeping through the night. 'I feel great, and even though I still have some pain, I have made many friends. Before, I was alone and isolated; now people in my qigong class call me to make sure I'm OK.'

According to Professor Richard Fielding, clinical psychologist at HKU's School of Public Health, chronic fatigue syndrome is a rather ill-defined condition, which is probably 'conflated with depression, as chronic fatigue is also a presenting symptom of depression'. Fielding has also observed that, while chronic fatigue is common, it may have many causes: overwork and poor sleep quality are the most likely cause in Hong Kong.

The term 'qigong' is sometimes confused with 'tai chi' or 'neigong'. Christel Wilk, founder of the Tian Yan Nei Gong Centre in Central, says choosing one over another should be based on what 'a person feels drawn to for their healing', as all three closely related art forms have physical components that cultivate balance or qi, yin and yang and the five elements - all cornerstones of traditional Chinese medicine's 5,000-year history.