Health and physical activity in Hong Kong – A review
Overweight and obese individuals that are physically active and fit have lower disease and early death rates than overweight and obese individuals that are sedentary and unfit. Regular physical activity not only decreases the risk of coronary heart disease but it also contributes to the reduction of various other disease risk factors resulting in overall better health. The benefits of physical activity are not limited to physical improvements, but have a positive effect on the overall wellbeing of an individual.
Hui, Dr. Stanley. ( 2001). Health and physical activity in Hong Kong – A review. Research Report No. 4. Hong Kong, China: Hong Kong Sport Development Board.
Extensive scientific research shows that regular physical activity and playing sport improves health in many ways. An active lifestyle is one of the best preventative medicines for reducing the risk of developing life-threatening diseases like heart disease, colon cancer and diabetes. Most of the research into the health benefits of sport and physical activity has been carried out on Caucasian populations. This review was commissioned by the Hong Kong Sports Development Board (SDB) to identify evidence of the health benefits of sport and physical activity for Chinese and Asian people. The review also presents new information about the levels of physical inactivity in Hong Kong and looks at the extent of health problems related to physical inactivity. Potential savings in health care costs that would result from a more active population are discussed. More education is recommended to increase awareness among Hong Kong Chinese about the benefits of sport and physical activity. SDB commissioned this review as part of its research programme to demonstrate the value of sport for Hong Kong. Reviews of the economic and community and social benefits of sport also are being carried out as part of this programme.
During the past few decades, there has been a growing trend in the number of overweight and obese individuals. According to results from the Third National Health and Nutrition Examination Survey, it has been determined that more than half of all adults living in the United States qualify as being overweight or obese when using the guidelines set forth by the National Institutes of Health (Must et al., 1999). In comparison, according to the Asian standards, it was established that over half (58% of men and 49% of women) of the Hong Kong population qualifies as being overweight (BMI>23) (Janus, 1997a). The health risks associated with obesity are numerous. For example, obesity is a known risk factor for several diseases, including CHD, cancer, and diabetes mellitus.
This review commissioned by the Hong Kong Sports Development Board (SDB) identified evidence of the health benefits of sport and physical activity for Chinese and Asian people. Specifically the Hong Kong Health Problems are:
1) Unlike the United States, the leading cause of death in Hong Kong is cancer, accounting for 32.7% of total deaths in 1998 (Hong Kong Department of Health, 1999).
2) The top five cancers affecting this population are lung, liver, colon, stomach, and rectum. Heart disease is the number two killer and a major health concern in Hong Kong, contributing to 15.5% of the deaths in 1998 (Figure 1).
3) Other leading causes of death of Hong Kong Chinese include pneumonia, cerebrovascular disease, injury and poisoning, nephrosis, septicaemia, liver disease and cirrhosis, diabetes mellitus, and aortic aneurysms (Hong Kong Hospital Authority Statistical Report, 1999).
In order to ease the heavy burden of health problems, recent focus has been placed on preventive medicine rather than treatment. Regular physical activity has been found to be one of the most important strategies in preventive medicine (U.S. Department of Health and Human Services, 1996). The studies that prove the benefits focus on the following areas:
Central obesity is the term used to describe the excess of visceral adipose tissue (VAT) in an individual. Central obesity is determined by calculating the waist-to-hip circumference ratio (WHR). In a literature review conducted by Ross (1997), it was determined through cross-sectional research that central obesity was more closely related to disease risk factors than evenly distributed obesity, proving that fat distribution has an important role in overall health.
A study by Megnien, Denarie, Cocaul, Simon, & Levenson (1999) observed 552 men and 160 women from the Paris area who were at risk for cardiovascular disease. This study found that abdominal fatness, or central obesity, was associated with an increase in disease risk factors and complications. High VAT levels are usually more prevalent in men, causing more disease risk factors in the male population. In addition, Ross’ review 1997) stated that more health problems are found in individuals that have high levels of VAT when compared to individuals that have an even distribution of fat.
Hill and Melanson (1999) suggested in a review that decreases in physical activity during the past few decades have contributed to increasing obesity in the United States. Moreover, the growing number of obese individuals can be associated with the growing, industrialised, high-tech society. In the past, more people had jobs that required them to obtain a substantial amount of physical activity. Today, more and more people are working in jobs that require them to remain quite sedentary, resulting in a decrease in daily energy expenditure. Unfortunately, this decrease in energy expenditure is not resulting in an equal decrease in energy intake. Simply put, people are consuming more calories than they are burning and are therefore, becoming obese (Hill & Melanson, 1999).
Blair and Brodney (1999) summarised the results of 24 obesity-related articles in order to determine the effects of obesity and physical inactivity on morbidity and mortality. Based on the results of the review, Blair and Brodney (1999) were able to conclude that overweight and obese individuals that are physically active and fit have lower disease and early death rates than overweight and obese individuals that are sedentary and unfit.
Furthermore, physical activity has a particular reduction effect on abdominal fat and serves as a prevention technique for additional weight gain (Ross et al., 2000). A similar study conducted by Utter, Nieman, Shannonhouse, Butterworth & Nieman (1998) observed the effects of diet and exercise on body composition in 91 obese women during a 12-week trial. For obese women in the study, a combination of both diet and exercise yielded an average loss of 8.1kg, while those participating in exercise alone had an average loss of only 1.45kg at the end of the 12-week period.
Coronary Heart Disease:
Despite the growing amount of information and public awareness on the prevention of certain risk factors for CHD, it remains the world’s number one cause of death (WHO, 2000). Unfortunately, deaths caused by CHD are often premature and preventable. Many of the risk factors for CHD are modifiable and can be eliminated by healthy lifestyle choices. These risk factors include smoking, high blood pressure, high blood lipid levels, obesity, diabetes, and physical inactivity. Regular physical activity not only decreases the risk of CHD, but it also contributes to the reduction of various other disease risk factors resulting in overall better health (NIH Consensus Panel on Physical Activity and Cardiovascular Health, 1996). Several well-documented studies serve as proof of the positive health benefits, including a decrease in CHD risk factors, of regular physical activity (Blair et al., 1996; Dunn et al., 1999; Kujala, Kaprio, Sarna, & Koskenvuo, 1998; Fletcher et al., 1996; Pate et al., 1995).
Among various non-communicable diseases, diabetes mellitus is one of the top killers because it accounted for more than 777,000 lives in 1999 (WHO, 2000). In the WHO 2000 World Health Report (WHO, 2000), a substantial rise in the number of diabetes cases was predicted for the coming years. It is estimated that the 1997 statistic of 135 million cases will escalate to 300 million cases by the year 2025. This rise in the prevalence rate of diabetes can be accredited to obesity, unhealthy diets, aging, and sedentary life styles (WHO, 2000). Diabetes can be either insulin-dependent (IDDM or type 1) or non-insulin-dependent (NIDDM or type 2). Non-insulin-dependent diabetes mellitus (NIDDM) is one of the major causes of disability and mortality (Wallberg-Henriksson, Rincon & Zierath, 1998). Roughly 90% of the worldwide diabetes cases are NIDDM (WHO, 2000). Although there is inconsistent evident that adaptations to routine exercise improve glucose control in IDDM, there is evidence that shows improved glucose control in individuals with NIDDM (Zinker, 1999). Nevertheless, both IDDM and NIDDM benefit from regular exercise.
Wannamethee, Sharper, & Alberti (2000) designed a prospective study with 5,159 men from England who were previously free of disease in order to determine the effect of physical activity on the incidence of CHD and NIDDM. After an average 17-year follow-up, the authors concluded that the risk of developing NIDDM decreased with increasing amounts of physical activity (Wannamethee et al., 2000). Similar results were collected from The Finnish Diabetes Prevention Study conducted by Uusitupa et al. (2000).
Some studies on this topic in regards to Mainland China. Chow et al. (1993) compared occupational information on 2,000 cases of colon cancer in Shanghai in order to classify incidence rates by the amount of work-related physical activity. An increased risk of colon cancer was observed in the men and women in the study with low occupational physical activity levels, such as business professionals (Chow et al., 1993).
The Nurses’ Health Study evaluated physical activity and risk of stroke in 72,488 female nurses in the United States. According to relative risk calculations, this cohort study found that the risk of stroke in women can be greatly reduced by moderate-intensity physical activity, which can be in the form of walking (Hu et al., 2000).
This study found that physical activity, especially lifelong, weight-bearing activity, reduces the risk of osteoporosis (Ulrich et al., 1999). A study in Hong Kong found similar results using 280 women and 120 men with hip fractures and 800 controls (Lau & Cooper, 1993).
When reviewing the effects of physical activity on health, it is imperative to consider the effects on mental health as well. The benefits of physical activity are not limited to physical improvements, but have a positive effect on the overall wellbeing of an individual.
Physical activity, particularly in the form of aerobics or strength training, is a proven treatment for depression and is associated with reducing anxiety and panic attacks (Fox, 1999; Paluska & Schwenk, 2000). Physical activity is also helpful in preventing and treating stress and increasing ability to cope with stressful situations (Shephard, 1997). In psychological tests, athletes scored better for tension, depression, anger, fatigue, and confusion than individuals who were sedentary (Shephard, 1997)
In order to determine what stage of life physical activity programs designed to prevent sedentary lifestyles in adulthood should be initiated, a 5-year, population-based study was implemented using 126 children in Muscatine, Iowa (Janz, Dawson & Mahoney, 2000).
It was concluded that increasing regular physical activity in children will prove to have positive health benefits in their adult lives and thus, improve the overall health of the population (Janz et al., 2000).
| © SDB, March 2001