Comparable Effects of High-Intensity Interval Training and Prolonged Continuous Exercise Training on Abdominal Visceral Fat Reduction in Obese Young Women

Abstract

This study compared the effect of prolonged moderate-intensity continuous training (MICT) on reducing abdominal visceral fat in obese young women with that of work-equivalent (300 kJ/training session) high-intensity interval training (HIIT). Forty-three participants received either HIIT (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn fontstyle="italic">15</mml:mn></mml:math>), MICT (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn fontstyle="italic">15</mml:mn></mml:math>), or no training (CON,<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn fontstyle="italic">13</mml:mn></mml:math>) for 12 weeks. The abdominal visceral fat area (AVFA) and abdominal subcutaneous fat area (ASFA) of the participants were measured through computed tomography scans preintervention and postintervention. Total fat mass and the fat mass of the android, gynoid, and trunk regions were assessed through dual-energy X-ray absorptiometry. Following HIIT and MICT, comparable reductions in AVFA (−9.1, −9.2 cm 2 ), ASFA (−35, −28.3 cm 2 ), and combined AVFA and ASFA (−44.7, −37.5 cm 2 ,<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M4"><mml:mi>p</mml:mi><mml:mo>&gt;</mml:mo><mml:mn fontstyle="italic">0</mml:mn><mml:mo>.</mml:mo><mml:mn fontstyle="italic">05</mml:mn></mml:math>) were observed. Similarly, reductions in fat percentage (−2.5%, −2.4%), total fat mass (−2.8, −2.8 kg), and fat mass of the android (−0.3, −0.3 kg), gynoid (−0.5, −0.7 kg), and trunk (−1.6, −1.2 kg,<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M5"><mml:mi>p</mml:mi><mml:mo>&gt;</mml:mo><mml:mn fontstyle="italic">0</mml:mn><mml:mo>.</mml:mo><mml:mn fontstyle="italic">05</mml:mn></mml:math>) regions did not differ between HIIT and MICT. No variable changed in CON. In conclusion, MICT consisting of prolonged sessions has no quantitative advantage, compared with that resulting from HIIT, in abdominal visceral fat reduction. HIIT appears to be the predominant strategy for controlling obesity because of its time efficiency.