Cancer-related fatigue is the most commonly reported symptom among children with cancer and its effect is long-lasting, remaining for years after treatment.Childhood cancer patients undergo chemotherapy and/or radiotherapy that impairs their normal body tissue and fitness. Consequently, cardiorespiratory function and muscle strength decrease, and fatigue is inevitable. More importantly, these complications do not disappear, but continue for months or even years after completion of therapy.

Increasing concern has been placed on the benefits of regular physical activity (PA) among young cancer patients to improve cardiovascular fitness, ameliorate fatigue, and reduce some of the adverse effects of cancer and its treatment. Various studies have shown improvements in quality of life among young patients undergoing cancer treatment by performing regular physical activity. However, the literature review found that most young cancer patients maintain a lower level of PA than before their diagnosis.

A recent study revealed that the current PA levels of Hong Kong young cancer patients were markedly reduced when compared with their pre-morbid situation. Moreover, they were significantly less active in performing physical exercise, and reported lower levels of quality of life than their healthy counterparts. These findings reveal a crucial obligation of health care professionals to advocate the significance of regular PA among young cancer patients.

It is crucial for healthcare to correct misconceptions about PA among parents of children with cancer and advocate the principle of regular PA for their children, with the aim of enhancing their physical and psychological wellbeing and promoting their quality of life. Nevertheless, a large body of evidence has shown that education alone is insufficient or unlikely to change behavior, and healthcare professionals must therefore explore strategies that can actually be effective in helping parents realize the importance of regular physical activities for their children with cancer. Most importantly, healthcare professionals should motivate parents, as the primary caregivers, especially during children's cancer treatment, to take an important role in encouraging their children with cancer to adopt regular PA.

This study aims at testing the effectiveness of using motivational interviewing with parents in encouraging their children with cancer to adopt and maintain regular physical activity.

Despite the mortality rates among cancer patients have been greatly reduced as a result of medical advances in cancer screening and treatment in recent decades, cancer itself and the adverse effects of treatment are still threatening to young cancer patients, with vast destruction in both physical and psychological aspects. In particular, cancer-related fatigue is the most commonly reported symptom among children with cancer and its effect is long-lasting, remaining for years after treatment. Childhood cancer patients undergo chemotherapy and/or radiotherapy that impairs their normal body tissue and fitness. Consequently, cardiorespiratory function and muscle strength decrease, and fatigue is inevitable. More importantly, these complications do not disappear, but continue for months or even years after completion of therapy. All these adverse effects clearly exert both short-term and long-term effects on children and adolescents, severely decreasing their quality of life.

Increasing concern has been placed on the benefits of regular physical activity among young cancer patients to improve cardiovascular fitness, ameliorate fatigue, and reduce some of the adverse effects of cancer and its treatment, including obesity, and osteoporosis. Various studies have shown improvements in quality of life among young patients undergoing cancer treatment by performing regular physical activity. However, the literature review found that most young cancer patients maintain a lower level of physical activity than before their diagnosis.

In a cross-sectional study to examine the physical activity levels and factors that affect their regular physical activity of Hong Kong Chinese childhood cancer survivors, the results revealed a significant decline in physical activity levels in childhood cancer survivors compared with their premorbid situation. In particular, an increasing number of cancer survivors took part in light-intensity activities, whereas a decreasing number of them participated in moderate to vigorous activity.

Another recent study revealed that the current physical activity levels of Hong Kong young cancer patients were markedly reduced when compared with their pre-morbid situation.The amount of time spent in high-intensity activity declined dramatically from 30.3% before diagnosis to only 1.3% during treatment. Moreover, they were significantly less active in performing physical exercise, and reported lower levels of quality of life than their healthy counterparts. These findings reveal a crucial obligation of health care professionals to advocate the significance of regular physical activity among young cancer patients.

There are some reasons to explain why Hong Kong Chinese children undergoing cancer treatment and childhood cancer survivors reported low physical activity levels. Similar to reports in the Western literature, to avoid cancer- or treatment-related fatigue, children are often advised by their parents or even healthcare professionals to take more rest and to reduce their amount of physical activity. In particular, the philosophy of Confucianism focuses on restoring harmony in our bodies to attain health, and this is strongly ingrained in the Hong Kong Chinese population. In this cultural context, cancer and other diseases are regarded as destroying harmony, whereas physical inactivity or rest restore harmony. As a result, childhood cancer patients and survivors are always resting, and they reduce vigorous activities as advised by their parents.

Nevertheless, such recommendation can accelerate fatigue as physical inactivity induces muscle catabolism and atrophy, which in turn may lead to a further decrease in functional capacity. Besides, because of the relatively low body resistance and high susceptibility to infection of children with cancer, many Chinese parents do not allow them near crowded public places, in particular during the seasonal outbreak of influenza, consequently affecting their level of physical activity. Moreover, academic achievement has traditionally been valued above all other forms in Chinese society. This may be due to the attitude commonly held by parents, and most schoolchildren, that academic achievement is related to a better career and brighter future. With this issue in mind, many children with cancer and survivors reported that they were anxious about their academic performance. As a result of suspension from school during the course of treatment and a decreased attention span, coupled with excessive tiredness after remission, they had to make extra efforts to catch up with their studies. Consequently, many did not have time to engage in regular physical activity. In addition, most children with cancer and survivors reported that they lacked encouragement by their parents and role models to follow and learn the physical activities that were appropriate for them to perform. Indeed, parents are influential in affecting the activities that the children performed. In particular, because of sociocultural emphasis on obedience and social conformity, Hong Kong Chinese children are more submissive when compared with Western children. A longitudinal study to examine the relationships between perceived parental psychological control and psychological well-being in Hong Kong Chinese children revealed that parental psychological control may inhibit the development of positive mental well-being and affect emotional life in children.

In sum, the decline in physical activity levels can be attributed to the fact that most Hong Kong Chinese parents overlook the significance of regular physical exercise for their children and misunderstand the effects of physical activity on recovery from cancer and treatment. It is crucial therefore for healthcare to correct misconceptions about physical activity among parents cancer and treatment. It is crucial therefore for healthcare to correct misconceptions about physical activity among parents of children with cancer and advocate the principle of regular physical activity for their children, with the aim of enhancing their physical and psychological well-being and promoting their quality of life. Nevertheless, a large body of evidence has shown that education alone is insufficient or unlikely to change behavior, and healthcare professionals must therefore explore strategies that can actually be effective in helping parents realize the importance of regular physical activities for their children with cancer.

Most importantly, healthcare professionals should motivate parents, as the primary caregivers, especially during children's cancer treatment, to take an important role in encouraging their children with cancer to adopt regular physical activity. There has been an increase in the use of motivational interviewing in lifestyle modifications. In particular, a growing body of evidence support the effectiveness of conducting motivational interviewing with parents to promote different behavioral changes for their children, including weight loss and eating habits. However, there is so far no study to examine whether using motivational interviewing with parents can help promote physical activity among children with cancer.This study aims at testing the effectiveness of using motivational interviewing with parents in encouraging their children with cancer to adopt and maintain regular physical activity.

Inclusion Criteria: (Children)

• aged between 9 to 16
• diagnosed with cancer at some time in previous six months and currently admit for cancer treatments
• do not participate in physical exercise and do not intend to start exercising in the next 6 months (pre-contemplation)
• who are able to speak Cantonese and read Chinese.

Exclusion Criteria:(Children)

• children with evidence of recurrence or second malignancies
• those with physical impairment or cognitive and learning problems identified from their medical records

Inclusion Criteria: (Parents)

• must be able to speak Cantonese and read Chinese
• one parent (either father or mother) who should be the main carer for the child with cancer will be selected

Exclusion Criteria: (Parents)

• Parents with emotional or psychiatric disorders, and cognitive and learning problems identified from their medical records