Vigorous-Intensity Physical Activities Are Associated with High Brown Adipose Tissue Density in Humans

Abstract

Brown adipose tissue (BAT) plays a role in adaptive thermogenesis in response to cold environments and dietary intake via sympathetic nervous system (SNS) activation. It is unclear whether physical activity increases BAT density (BAT-d). Two-hundred ninety-eight participants (age: 41.2 ± 12.1 (mean ± standard deviation), height: 163.6 ± 8.3 cm, weight: 60.2 ± 11.0 kg, body mass index (BMI): 22.4 ± 3.0 kg/m2, body fat percentage: 25.4 ± 7.5%) without smoking habits were categorized based on their physical activity levels (a group performing physical activities including walking and moderate physical activity (WM) and a group performing WM + vigorous-intensity physical activities (VWM)). We measured the total hemoglobin concentration ([Total-Hb]) in the supraclavicular region, an index of BAT-d, and anthropometric parameters. [Total-Hb] was significantly higher in VWM than WM for all participant groups presumably owing to SNS activation during vigorous-intensity physical activities, and unrelated to the amount of total physical activity levels. Furthermore, multiple regression analysis revealed that BAT-d was related to visceral fat area and VWM in men and related to body fat percentage in women. We conclude that vigorous-intensity physical activities are associated with high BAT-d in humans, especially in men.

Acute Interval and Continuous Moderate Intensity Exercise Enhanced Circadian Thermogenic Activity through Browning related Genes in Obese Adolescent Female

“…It is in line with the results of previous studies that the increased expression of the UCP-1 thermogenic gene in obese non-diabetic adults after giving 70%-80% intensity exercise [46]. In their study, Tanaka et al [15] also concluded an increase in UCP-1 expression in adult men with average body mass index after moderate-intensity walking exercise [15]. Research using experimental animals with weight exercise also concluded that exercise increases the UCP-1 thermogenic gene [47], activity of thermogenic genes such as PGC-1α, UCP-1, as well as acid transport genes after moderate-intensity continuous exercise and high-intensity interval exercise [29].…”

“…Therefore, a non-pharmacological approach based on exercise is required. Exercise carries physiological effects that significantly affect the body [13], one of which it increases the expression of the thermogenesis gene [14] and activates the adipose network, decreasing lipid accumulation [15]. Therefore, the preparation of an exercise program as a non-pharmacological therapy for obese individuals through increasing activity of thermogenic genes is interesting to be developed further [16].…”

“…The results of previous in vivo animal models concluded that high-intensity exercise increased transformation to thermogenic genes faster than moderate-intensity exercise [29]. Inversely, other studies have concluded that moderate-intensity exercise is more beneficial than a high-intensity exercise in increasing response and adaptation to the browning gene and cause no systemic injury to muscles [15]. High-intensity exercise increases the browning gene adaptation faster, but it carries a higher risk of inflammation and systemic injury [17].…”

“…In addition, exercise is predicted to be an effective and strategic method for improving metabolic health [34] and improve metabolic profiles [35]. Although previous studies claim that exercise can enhance the performance of thermogenic gene expression related to metabolism [15,29], but the effect of acute interval training and continuous moderate-intensity exercise on changing the thermogenesis profile of circadian genes in obese individuals has not been investigated, further. Therefore, this study seeks to uncover changes in the circadian profile of thermogenic gene expression after the acute interval and continuous moderate-intensity exercise.…”

The Role of Exercise, Diet, and Cytokines in Preventing Obesity and Improving Adipose Tissue

“…The findings showed a remarkable reduction in VAT in the high-intensity group exhibited, while no change was observed in the moderate group [ 67 ]. A recent study reported that vigorous-intensity physical activities are associated with high BAT density in humans, suggesting that long-term high-intensity physical activities might positively influence BAT content [ 68 ]. Collectively, the intensity of exercise training seems to play an essential role in changing adipose tissue.…”