Can exercise enhance the lives of those with prostate cancer?
Exercise may increase the quality of life for patients
Surgery, radiotherapy and hormone therapy - the usual treatments for prostate cancer sufferers - are certainly far from appetising. Could there be a more palatable option in the form of exercise?
Researchers at the University of Hong Kong's Institute of Human Performance are conducting a study on exercise as medicine among a group of local men with prostate cancer.
The researchers are seeking to evaluate the physical and psychological benefits of traditional Chinese mind-body exercise compared to that of a Western programme of resistance and aerobic exercises.
The study is funded by Movember, the moustache-growing charity event held each November that raises funds and awareness for prostate cancer and other men's health issues.
To date, about HK$600,000 has been awarded to the study, one of two new projects by the Cancer Fund - the main beneficiary of Movember HK - in collaboration with the University of Hong Kong to improve patients' quality of life.
The other project seeks to develop a psychometric screening tool to measure the health-related quality of life in Chinese patients with prostate cancer.
In the past 10 years, there's been an increase in prostate cancer in Hong Kong men. The number of new cases each year has more than doubled from 786 in 2001 to 1,644 in 2011. The disease is now the third most common cancer in men, behind lung and colorectal cancers.
A growing body of research suggests that exercise may maximise the chances of longer survival and/or improved quality of life in men with prostate cancer. But all the studies have looked at Western, rather than Eastern, regimens of physical activity.
"[Men in the] predominantly Chinese culture of Hong Kong may engage more readily in traditional Chinese movement exercise such as tai chi," says principal investigator Dr Michael Tse, director of the Institute's Active Health Clinic.
"However, the physical and psychological benefits [of such exercise] for prostate cancer patients are less known."
To find out, Tse and his team - which includes exercise and psycho-oncology experts in prostate cancer from Australia's Edith Cowan and Griffith universities - recruited 41 local prostate cancer patients in September through urologists, oncologists and the Cancer Fund's support groups.
To be selected, the patients had to be free of conditions which would put them at risk during exercise. The participants - aged 57 to 85, with an average age of 69 - were put through a series of tests to measure their strength, body composition (such as muscle and fat mass), cardiorespiratory fitness, blood pressure, flexibility and balance, as well as psychometric screening tests to evaluate their quality of life.
They were then randomly assigned to one of three groups: Eastern exercise, Western exercise or a delayed exercise control group. Last month, the groups embarked on a 12-week programme of thrice-weekly sessions.
With the Eastern programme, participants practise luk tung kuen ("six circulation fist"), which is composed of a sequence of 36 movements, each repeated five to 10 times.
The Western programme sessions consist of resistance training of three to four sets of six to eight exercises, and cardio work done on treadmills, stationary bicycles and cross-training machines.
In the control group, participants maintain their usual lifestyle - in particular, they have been told not alter their physical activity patterns.
Next month, at the end of the 12 weeks, all participants will go through the battery of tests again. Men in the control group will also then embark on either the Eastern or Western programme for the next 12 weeks. The final study report will be ready by about August next year, Tse says.
"We believe that all forms of exercise may have some benefit [for patients], and while we have hypotheses about the outcomes, we expect there may be some differences between the groups," says Tse.
"Aside from the differences between exercise modes, we also hope to evaluate if a best practice Exercise Is Medicine prescription is feasible, acceptable and effective in Chinese men."
Exercise Is Medicine is a global initiative of the American College of Sports Medicine that's committed to the belief that physical activity is crucial for the prevention and treatment of diseases, and should be regularly assessed and treated as part of all medical care.
Tse says so far some of the study participants are sleeping better and having an improved appetite, while others report better stabilisation of their glucose levels.
The risk of prostate cancer progression and death from the disease can be reduced through vigorous physical activity, according to a landmark study by researchers at the Harvard School of Public Health and University of California, San Francisco.
Men who did vigorous activity - defined as more than three hours per week - had a 61 per cent lower risk of prostate cancer-specific death compared with men who did less than one hour per week.
The study, published in 2011 in the
Journal of Clinical Oncology, tracked 2,705 prostate cancer patients over an 18-year period. The men reported the average time per week they spent doing physical activity, including walking, running, bicycling, swimming and other sports and outdoor work.
Tse cites other studies that have shown that the appropriate exercise prescription can benefit prostate cancer patients in symptom management and mitigate fatigue associated with radiotherapy. It can also improve body composition, quality of life, mental health, functional capacity and reduce the risk of cancer recurrence.
In addition, says Tse, exercise has been shown to be a very effective medicine for counteracting the effects of hormone therapy, which include loss of muscle and bone, increased fat mass, increased incidence of metabolic syndrome, cardiovascular disease and sudden death.
Exercise could also provide the psychological boost that many prostate cancer sufferers seek and need.
"There's a lot of stigma attached to prostate cancer. In Chinese culture, prostate cancer is a taboo associated with impotence and death. A lot of men diagnosed with the condition lose confidence," Tse says. "Exercise can improve confidence and quality of life in patients."
Paul Villanti, executive director of programmes at Movember, says the charity is investing "very heavily" in exercise because of the growing body of evidence of its benefits for men with prostate cancer. For example, one major clinical trial - a collaboration of scientists around the world with A$8.8 million (about HK$60 million) in funding from Movember - seeks to establish an optimal exercise protocol to maximise quality of life and survival of men with advanced prostate cancer, and unravel the molecular mechanisms underpinning the beneficial effects of exercise in men with advanced disease.
"There are a lot of studies, but all very different," says Villanti. "The reason we liked Michael [Tse]'s project is it's really the only one we're investing in that compares Eastern versus Western exercise regimens. We're certainly looking forward to seeing the results of this project and sharing the knowledge globally."
Despite the overwhelming scientific and clinical rationale for men with prostate cancer to pursue a lifelong exercise programme, Tse says participation by cancer patients in regular physical activity is less than 15 per cent.
"Strategies which can increase participation in quality exercise programmes are a substantial priority for the clinical management of prostate cancer."