Studies have shown no significant differences between low-fat diets and low-carb diets, both of which provide good weight-loss benefits.Diet control is currently recognized as one of the effective ways to lose weight, but in fact, long-term diet not only reduce the metabolic rate, but also increase appetite. Once you eat again, your excess weight will come back again.
Therefore, some people suggest that exercise can help maintain the weight loss results. But this remains to be confirmed by RCT, making small controversy. Obviously, it is certainly beneficial to do regular exercise, so what makes controversy? Let’s check the main three questions and the answers from Physiology & Behavior.
Question 1: The results of previous observational and RCT studies vary greatly.
The heterogeneity of previous researches is the biggest question. The results of previous observational and RCT studies vary widely from “very effective” to “ineffective.”
In fact, the positive result is not ideal for many reasons, here are two main reasons:
① insufficient exercise makes the result not obvious.
Most of the previous studies are relatively small in terms of sample size, and the test efficiency is not strong enough.
Study in Physiology & Behavior provides daily one-hour exercise, from light to moderate, which far exceeds the WHO recommended exercise. Therefore, the inconsistency of previous research findings may lie in insufficient exercise.
② compliance offset.
RCT test itself can cause the deviation of compliance. In most RCTs, participants had high withdrawal rates.
Question 2: The effect of exercise varies from person to person
Question 2 seems plausible: How much energy is consumed by exercise depends on many factors, such as age, sex, oxygen demand, and even the sensitivity to exercise (determined by the gene), so there is no guarantee that exercise works for everyone. Then the most urgent task is to reveal the inherent mechanism between exercise and weight loss, a mechanism that has nothing to do with the confounding factors such as age and gender.
As we all know, an important reason for weight loss rebound is the “energy gap”, namely, the intake of more than the energy consumed.
The purpose of exercise is to minimize this energy gap. Exercise makes higher leptin and insulin sensitivity, improving liver metabolism and decreasing hunger. As a result, oxygen and energy consumption of peripheral tissue increased, and ultimately maintained your weight.
A recent study showed that exercise can also improve the special dynamic effects of things and make the process of converting energy into weight more “expensive.”
Most gratifying is that the longer you maintain your ideal body weight, the more aggressive your body will be able to adapt to, thus creating a positive cycle of weight loss. But the author does not deny that, for different genders, insist on exercise to delay the effect of weight rebound really do not vary.
In a large study, men who insisted on exercise lost an additional 5.2 kg over 16 months compared to those who did not exercise, while there is no significant difference between the two groups. But at least for men this is absolutely valid, right?
Question 3: Subtle weight loss psychology
The last question actually has nothing to do with the effectiveness of exercise itself. Some fitness lovers may have discovered that after exercise, there is often a subtle psychological hint: I have consumed a lot of calories, and it’s ok to eat more; I have run three kilometers, so maybe I just hire a taxi to work.
This behavioral “compensation” may result in a drastic reduction in the weight-loss benefits of exercise. But this does not mean that exercise itself is invalid! Therefore, this kind of self-reward mechanism is totally dangerous!
In conclusion, although it is not yet confirmed that “exercise can effectively lose weight,” there is no doubt that there is a positive correlation between insisting on exercise and maintaining weight loss. Of course, the premise is to insist, because insisting brings victory!