Exercise intervention. The experimental group increased their energy expenditure according to American College of Sports Medicine and WHO-based physical activity recommendations for all adults to promote clinically significant weight loss and for additional health benefits: 300 min of moderate-intensity aerobic training throughout the week (WHO, 2010; Swift et al. 2014). Participants underwent five 60 min moderate-intensity cycling sessions per week for a period of 8 weeks, 40 sessions in total. Each session involved 5 min of warm up at 40 Watts, cycling for 50 min at a speed that increased their HR to a target HR obtained at 50-60% of peak VO2, and a 5 min of cool down at 40 Watts.

. In the control group, participants did not undergo any intervention and were instructed to maintain their regular physical activity and diet regime for 8 weeks.

8-week aerobic exercise (moderate intensity), 5 times per week, 60 min per session. Exercise training under supervision of trained staff.

weight (TBF-300 body composition scale; Tanita, UK Ltd., UK) was measured while the participants wore only underwear and were barefoot.

Venous blood samples (5 mL) were collected and allowed to clot at room temperature. Serum was then separated by centrifugation for 15 min at 1,200 g (room temperature) and stored at -80°C until analysis. BDNF were measured using an enzyme-linked immunoassay system (Gemini; Stratec Biomedical, Birkenfeld, Germany).

Automated Neuropsychological Assessment Metrics Version 4 (ANAM-4; Vista Life, USA) was used to measure neurocognitive skills: motor reaction time, mental flexibility, mathematical processing, working memory, visual scanning and associative learning skills. Participants were familiarized with the test battery twice before the experiments.

Aerobic fitness was assessed by a graded exercise test on an electronically braked cycle ergometer (Ergoselect 100, Ergoline, Bitz, Germany). Standardized verbal encouragement was provided throughout the test to stimulate maximal performance.

Waist circumference was measured to the nearest 0.1 cm, in duplicate, at the level of the iliac crest at the end of the normal expiration. Hip circumference was measured at the maximum protuberance of the buttocks. Waist and hip circumferences were measured at the nearest 0.5 cm.