Advanced Exercise for Weight Loss: Analysis of the Advantages and Disadvantages of Interval Training and High-Intensity Strength Training, and the Principle of Personalized Prescriptions

Moderate-intensity, prolonged, continuous exercise is a common form of exercise for weight loss. This type of exercise provides ample oxygen supply during the workout, and as the exercise duration increases, the proportion of energy derived from fat reaches its peak, facilitating the mobilization and utilization of body fat and resulting in excellent weight loss effects. Interval exercise is a type of intermittent exercise. Based on the different rest and recovery times between workouts, intermittent exercise is divided into repetitive exercise and interval exercise. Repetitive exercise involves no fixed recovery time between workouts, allowing for sufficient rest before the next workout. Intermittent exercise involves a fixed recovery time between workouts.

Moderate-intensity, prolonged, continuous exercise is typical aerobic exercise. Even with several short rest periods during the exercise, the body's functional level does not significantly decrease during these short rest periods, thus not significantly affecting the metabolic process and can still be considered continuous exercise. Intermittent exercise is generally a type of exercise that incorporates rest periods for recovery during activities primarily powered by anaerobic energy, depending on the specific training objective. Repetitive exercises are generally used in high-intensity, short-duration training.

Interval training is generally used during high-intensity, long-duration exercise. Its purpose is to improve an athlete's ability to produce, buffer, and tolerate lactic acid; in other words, it's a high-intensity, high-lactate training method. If the intensity of intermittent exercise is in the low-to-moderate range, the duration is long, and the rest intervals are short, it is essentially a form of continuous exercise. During weight loss through exercise, rest intervals should not be too long; 2-3 minutes is sufficient. Excessive rest will inevitably lead to a significant decline in bodily functions.

Strength training, as an important form of exercise, can indeed burn calories. Compared to low-to-moderate intensity, long-duration exercise for weight loss, high-intensity strength training primarily uses muscle glycogen as its energy source. If glucose is not consumed promptly after exercise, the body will break down fat for energy. Therefore, the proportion of energy derived from fat increases after high-intensity strength training. With consistent strength training, skeletal muscle volume significantly increases, leading to a rise in basal metabolic rate, which in turn helps burn fat.

However, high-intensity strength training is often difficult to sustain for extended periods, so the total energy expenditure is not necessarily greater than that of prolonged aerobic exercise. Furthermore, this type of exercise is typically anaerobic, meaning that oxygen intake during exercise cannot meet the body's oxygen requirements. Energy is primarily provided through anaerobic glycolysis of muscle glycogen during exercise. The metabolic product of glycolysis is lactic acid, and skeletal muscle cells can only utilize fat for energy through aerobic oxidation when lactic acid is cleared. Moreover, excessive lactic acid buildup in the body often leads to muscle soreness after exercise, and post-exercise fatigue takes longer to subside.

Therefore, high-intensity strength training is generally not used during exercise for weight loss. Only in the later stages of exercise for weight loss is it appropriate to increase localized low-to-moderate load strength and endurance exercises. This type of exercise not only has a better weight loss effect but also allows obese patients to develop a more favorable body shape due to the increase in local skeletal muscle volume. The basic principle for obese patients to lose weight through exercise is to be individualized and proceed gradually. The so-called "individualized" approach emphasizes that exercise for weight loss is not a one-size-fits-all method but should be tailored to the specific circumstances of the obese patient, such as gender, age, weight and degree of obesity, health condition, and exercise capacity.

To ensure a personalized approach, it's crucial to emphasize that exercise intensity must align with the obese individual's health condition and fitness level, using testing to determine an accurate target heart rate. Furthermore, the choice of exercise should consider both easily controllable intensity and the obese individual's interests and preferences. For instance, if an obese individual enjoys both badminton and brisk walking, brisk walking should be prioritized because its intensity is easier to manage. "Gradual progression" is also a vital principle in the exercise-based weight loss process. This requires constant monitoring of the obese individual's physical condition and fitness level, allowing for timely adjustments to the exercise plan.

Especially in the initial stages of exercise, extra caution is needed. Generally, obese individuals exercise less and have lower physical fitness. In the early stages, the body may not be able to withstand the exercise load, and forcing exercise could easily lead to injury. For example, for an obese patient weighing over 300 pounds, swimming is the first choice when starting to lose weight. Once the weight has decreased to a certain level, walking and swimming can be alternated. When starting walking, the pace should be primarily leisurely. As weight loss and physical fitness improve, the walking speed can be gradually increased. Don't rush; exercise scientifically under the guidance of a professional to ensure the safety and effectiveness of weight loss through exercise.