But it is fortunately possible to reduce our body fat and especially abdominal fat to find a flat stomach and health.
In theory, losing weight should be relatively simple. It is only a matter of restoring a balance between caloric intake and expenditure, for example by eating less and moving more.
In reality, losing weight, and especially maintaining these losses over the longer term, is a difficult goal to achieve. Besides, the majority of overweight people fail to perform successfully.
This difficulty is mainly due to the fierce resistance of our metabolism to any weight loss. Whether in response to a lack of food or an increased level of physical activity. We are programmed to maintain a stable weight. A caloric deficiency is immediately compensated by a corresponding decrease in the energy expended by the body. For example by decreasing the basal metabolic rate, while an increase in physical activity will cause an increase in appetite to recover the excess calories expended.
Walk 6.5 km to burn the calories of a cake
Trying to lose weight by doing more exercise is all the more frustrating because it takes a very intense effort to expend the excess calories from what we eat. For example, an average person has to walk about 6.5 km to burn 400 calories from a single piece of cake, which is practically impossible in routine. For all these reasons, the current scientific consensus is that exercise alone does not lead to major weight loss. It is necessary to reduce the calories ingested in parallel to achieve this. Contrary to popular belief, the level of physical activity today is very similar to what it was 30 years ago. It is therefore not the decrease in physical activity that can explain the global obesity epidemic, but our overconsumption of industrial foods filled with empty calories.
The enemy of health: abdominal fat
If exercise is not a panacea for weight loss, it remains very important in the fight against obesity. On the one hand, regular exercise is shown to be very important for the long-term maintenance of the weight lost by a low-calorie diet. On the other hand, research from the past few years shows that exercise can specifically target certain fat stores. Especially at the abdominal level. This mass of abdominal fat is very harmful to health. It leads to the development of pro-inflammatory conditions that disrupt metabolism and increase the risk of cardiovascular disease, type 2 diabetes, certain cancers and even dementia. Any reduction in this abdominal fat mass through exercise can therefore have very positive repercussions on health.
Destroy belly fat in 12 weeks
The results of a clinical study indicate that this positive effect of exercise is due to interleukin-6. It is a cytokine molecule secreted by muscle cells during physical exertion. In this study, 53 sedentary participants with abdominal obesity (waist circumference greater than 88 cm for women and 102 cm for men) were recruited. They were treated or not with an antibody that neutralizes interleukin-6 (tocilizumab) and subjected or not to an intensive 12-week exercise program (with several sessions of 45 minutes of stationary bicycle each week). This experiment made it possible to show that regular training effectively makes it possible to reduce the mass of visceral fat (225 g on average, or 8%).
Flat stomach and better health
However, no reduction was observed in volunteers who had received the anti-interleukin-6 antibody. In addition, the researchers also noted that in inactive people, the blocking of interleukin by the antibody caused an increase in visceral fat mass (nearly 300 g). According to the authors, these results clearly demonstrate that interleukin-6 is the main factor responsible for lipolysis (fat destruction) in abdominal fatty tissue.
Reducing abdominal adiposity is therefore added to the long list of health benefits of regular physical activity. Whether in terms of reducing the risk of cardiovascular disease, diabetes, several cancers and dementia, exercise remains the key to living a long and healthy life.
Sources
Westerterp KR and JR Speakman. Physical activity energy expenditure has not declined since the 1980s and matches energy expenditures of wild mammals. Int. J. Obes. ; 32: 1256-63.
Verheggen RJ et al. A systematic review and meta-analysis on the effects of exercise training versus hypocaloric diet: distinct effects on body weight and visceral adipose tissue. Obese. Rev.; 17: 664-90.
Wedell-Neergaard AS et al. Exercise-induced changes in visceral adipose tissue mass are regulated by IL-6 signaling: a randomized controlled trial. Cell Metab.
