The holiday passes quickly, but the fat lingers on.
Though the National Day holiday ended over a week ago, many still lament over their expanding waistlines: "Every holiday adds three pounds!"
Thus, countless individuals have reignited their long-running battle against the bulge.
After years of the painful cycle of "dieting year after year, yet still gaining weight," who doesn't know a few seemingly professional terms like "calories," "basal metabolic rate," and "muscle gain"?Many believe that knowing these terms means they've mastered the "ultimate weight loss secret." Guided by the theory that "weight loss is all about controlling calorie intake," they meticulously count every calorie. Influenced by the idea that "weight loss is about burning fat," they don sweatpants and go on intense walks... But after all this effort, they end up exhausted with little to show for it.
Feeling like "this is too hard"? Maybe it's because the "knowledge" you've acquired about weight loss isn't entirely accurate.
Key Point 1: Consuming Only Basal Metabolic Rate Calories Is Unsustainable
Even the most casual dieter knows that, aside from genetic factors and pathological causes, most obesity stems from a calorie surplus. When the body takes in more energy than it expends, the excess is stored as fat.Thus, calorie-tracking apps became standard equipment.
So, can eating only enough calories to meet your basal metabolic rate—or maintaining a long-term low-calorie diet—actually lead to successful weight loss?
The answer is likely: No.
In reality, the body's total daily energy expenditure comprises three components: basal metabolic rate (BMR), thermic effect of food (TEF), and energy expenditure from physical activity. BMR determines the body's fundamental energy requirement, supporting vital functions like cellular processes and protein synthesis. It accounts for 60%–75% of daily energy needs.
The precise definition of basal metabolic rate (BMR) refers to the heat dissipated per unit time (typically per minute or hour) per square meter of body surface area. This measurement occurs under neutral, mild environmental conditions: immediately upon waking in the morning, after digestion and absorption (meaning the digestive system is inactive, requiring at least 12 hours of overnight fasting), with normal breathing and complete relaxation (lying flat, without any external muscle movement).
Basal energy expenditure is calculated by multiplying the basal metabolic rate by a time coefficient, though people commonly refer to basal energy expenditure as the basal metabolic rate or basal metabolism.
Gu Chuanling, one of China's first registered nutritionists and a member of the Chinese Nutrition Society, analyzed that for adult female manual laborers (which most white-collar women fall under), the average daily energy requirement is 1800 kcal. If one only consumes enough to meet the basal metabolic rate, the maximum intake would be 1350 kcal.Even with zero activity, this would still leave a 450-kcal deficit compared to 1800 kcal, inevitably causing hunger (most people feel hungry when intake drops below 300 kcal). Sustaining daily hunger is unsustainable, making weight loss difficult to achieve."Calorie control is essential during fat loss, but sustaining a diet at or below basal metabolic rate long-term is unsustainable. You'll inevitably feel hungry and miserable—and painful habits rarely endure," she explained. More critically, she stressed that while restricting calories, adequate intake of all nutrients—including protein and vitamins—must be maintained.
Key Point 2: Sweating Has Little to Do with Calorie Burn
When it comes to weight loss, many immediately associate it with profuse sweating. Indeed, stepping on the scale after a sweat-drenched workout often shows a lower number, leading many to wrap themselves in plastic wrap or sweat suits while running—as if the sweat flowing out were fat itself.
But is sweating actually burning fat? The truth is disappointing. The weight loss after heavy sweating is merely water loss from the body, not fat.
Chen Gangrui, a physical rehabilitation specialist at the Scientific Training Center of Nanjing Sport University, analyzed an experiment conducted by researchers at Colorado State University. The study focused on participants in a 90-minute hot yoga class.Eleven women and eight men participated in a 90-minute hot yoga session, performing 26 distinct poses plus two breathing exercises.
The final results revealed that a sweat-drenched hot yoga class burned no more calories than a regular yoga session with minimal perspiration.In other words, when exercise intensity remains constant, increased sweating does not lead to greater calorie expenditure.
Does this mean sweating has no connection to fat loss? Chen Gangrui clarifies that it's not entirely absolute. For the same individual exercising under identical conditions, higher intensity and longer duration typically result in more perspiration.In other words, excluding environmental and individual factors, sweat output is directly proportional to exercise intensity and volume. Generally, higher exercise volume correlates with better weight loss results.
Therefore, sweating isn't the sole indicator of whether a workout achieves fat-burning effects, but it can serve as a supplementary reference alongside other metrics to assess whether your exercise intensity was sufficient for the day.
However, Chen Gangrui cautions that a case occurred in Beijing where a girl wore a down jacket while running in summer to sweat more, ultimately suffering heatstroke. The reason is simple: sweating serves to dissipate heat and cool the body. Wrapping oneself in plastic wrap or wearing so-called sweat-wicking clothing drastically reduces this cooling efficiency, leading to only one outcome—rising body temperature, causing heatstroke and high fever, which can even be life-threatening.Heavy sweating doesn't necessarily mean better weight loss results; it actually signals the need for more hydration.
Key Point 3: Fat Can Never Be Converted into Muscle
Another common wish regarding weight loss is the idea that if only body fat could be transformed into muscle—reducing fat while building muscle, a perfect solution.
Sadly, this is impossible. Fat and muscle are fundamentally different substances that cannot be simply converted into one another. Muscle is a tissue that constitutes the human body. Based on location and characteristics, it is divided into three types, distributed across organs, tissues, and skeletal surfaces. Each muscle forms an organ alongside its controlling nerves, nourishing blood vessels, surrounding connective tissue, and bone attachments.
The human body contains approximately 639 muscles. These are composed of roughly 6 billion muscle fibers, with the longest reaching 60 centimeters and the shortest measuring only about 1 millimeter. Muscle typically accounts for 35%–45% of an average person's body weight.
Fat, in reality, encompasses many types, such as phospholipids, triglycerides, steroids, and glycolipids.In nature, mixed triglycerides are the most abundant, comprising 98% of dietary fat and over 28% of body fat.
Muscle's fundamental building blocks are amino acids, composed of carbon, nitrogen, hydrogen, and oxygen atoms. Fat, however, contains only carbon, hydrogen, and oxygen atoms. These two substances are analogous to egg whites and yolks—they cannot be converted into one another.
Fitness trainer Fan Hui explains that muscle tissue gain or loss primarily depends on exercise intensity, while fat tissue changes are determined by calorie intake. High calorie intake combined with low exercise naturally increases fat and reduces muscle, leading to weight gain. Conversely, high calorie intake paired with high exercise may result in gains in both muscle and fat.Fan Zhihong clarifies that fat can never transform into muscle, but exercise can burn fat. "When the body senses insufficient muscle strength to handle an activity, it converts dietary protein into amino acids to build bodily protein. Exercise allows simultaneous fat loss and muscle gain, increasing muscle proportion while decreasing fat proportion—resulting in a slimmer, more sculpted physique."