Overweight and obesity are a global epidemic associated with an increased risk of developing chronic diseases such as diabetes, hypertension, and other metabolic syndromes.
A body mass index (BMI) of 25 – 29.9 kg/m2 represents overweight conditions, and 30 kg/m2 and greater indicates obesity states.
Population studies estimated that 68% of U.S adults are classified as either overweight or obese (34% obese). In children and adolescents, statistics indicate that 32% are overweight or obese.
Overweight and obesity are associated with an increased risk of developing chronic diseases such as:
- Cardiovascular disease (CVD)
- Forms of cancer
- Musculoskeletal problems
Also, health implications related to obesity conditions account for high costs in the health system.
Excess Caloric Consumption
Several medical conditions can cause weight gain; however, these medical conditions are rare. In most cases, overweight and obesity are the results of inadequate energy expenditure or excess caloric consumption.
Multifactorial causes can contribute to gaining excess fat stores –
The two most critical factors to maintain a healthy weight are:
- Healthy diet
- Regular physical activity
Weight management is dependent on energy balance-
- The number of calories consumed
- The number of calories expended
Thus, to reduce body weight, negative energy balance must be achieved – meaning that caloric expenditure should be more significant than caloric intake.
Developing realistic and specific weight loss goals is essential to achieve adequate results. The ACSM recommends a 3%-10% weight reduction in overall body weight to achieve health benefits.
A safer and effective weight-loss method should occur at a rate of 1-2lb per week, equal to a daily caloric deficit of 500–1,000 calories.
Total Energy Expenditure
Total energy expenditure (TEE) represents the total number of calories expended and reflects the energy needed in all body metabolic processes.
3 components to determining TEE:
- Resting energy expenditure (REE or resting metabolic rate [RMR] or basal metabolic rate [BMR]): 60%–70% TEE
- Thermic effect of food: 10% TEE
- PA expenditure: 20%–30% TEE
Effective Training Methods
The most effective known method for weight loss is diet and moderate-vigorous physical training. According to the ACSM, the exercise program’s time should be greater than 150 minutes per week.
However, to maintain better body weight, it is recommended to engage in more than 250 minutes a week of moderate-vigorous physical activity.