Obesity Is a Disease
With solid evidence about the impact of obesity on health, the American Heart Association (AHA) has recently declared "obesity" as a disease in order to call for a public effort to combat this life-threatening "enemy". For overweight and obese people (Asian BMI > 23 kg/m2), a combination of an adequate amount of exercise and a balanced diet is very important for achieving weight loss. Research evidence has shown that even 5 – 10% of weight loss can result in significant health benefits, which are likely to be sustained by the maintenance of weight loss and regular exercise1. Health benefits associated with weight loss for individuals with overweight or obesity include:
- better cardio-respiratory and circulatory systems;
- improved metabolic system: by improving the sensitivity of cells to insulin, thereby reducing the risk of diabetes;
- improved functional ability: strengthened muscles for better tolerance for various physical tasks that require endurance and flexibility; and
- reduced depression: exercise can boost the "good" emotion-related hormone (e.g. endorphin), thereby maintaining a better mood for individuals.
Exercise recommendations
Unlike the average healthy adults, overweight/obese persons need extra amount of physical activity to induce weight loss and prevent weight regain. For them, the following general exercise regimen is recommended. If you have been leading a sedentary lifestyle for a long time, and/or if you have other health conditions (e.g. diabetes or hypertension), please consult your family doctor before following the exercise instructions below:
| Frequency | 5 – 7 day/week |
|---|---|
| Intensity | Moderate to vigorous |
| Time (duration) | At least 30 min/day; to be increased gradually to 60 min/day, with a goal of accumulating a total of 300 min/week. An alternative way to achieve the daily target is to accumulate exercise bouts of at least 10 min each. |
| Type | The primary mode is aerobic exercise involving large muscle groups (e.g. walking, jogging, cycling, swimming, etc). Also, resistance exercise should be included in workout routine to strengthen major muscle groups. |
Source: adapted from ACSM's Guidelines for Exercise Testing and Prescription 9th ed. 2013.
Apart from increasing energy expenditure through physical activity, a reasonable cut of energy intake through a low-fat diet (energy from dietary fat about < 30% of total daily calorie intake) should also be adopted to maximise the result of weight loss. Without this, the effect of weight management programme could be drastically compromised. In addition, for long-term weight management, overweight/obese individuals should also reduce sedentary lifestyle, which prevents weight loss and increases the risk of chronic diseases; to be more specific, they should avoid prolonged sitting at work, at home or in their leisure time. For more information on diet and physical activity for a healthy weight, please visit www.healthatwork.gov.hk.
1 Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults – The Evidence Report. National Institutes of Health. Obesity Research. 1998;6 Suppl 2: 51S-209S.
Top
