Responses of Obese and Non-obese Boys Cycling in the Heat

• Published in: International journal of sports medicine 2012-06, Vol.33 (6), p.497-501
• Main Authors: Sehl, P. L., Leites, G. T., Martins, J. B., Meyer, F.
• Format: Article
• Language: English
• Subjects: Adolescent; Bicycling; Bicycling - physiology; Biological and medical sciences; Boys; Child; Clinical Sciences; Fundamental and applied biological sciences. Psychology; Heart Rate - physiology; Heat; Hot Temperature; Humans; Male; Maximum oxygen consumption; Medical sciences; Metabolic diseases; Obesity; Obesity - physiopathology; Oxygen Consumption - physiology; Professional sports; Sports medicine; Surfaces; Sweat; Sweating - physiology; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports
• ISSN: 0172-4622; 1439-3964
• DOI: 10.1055/s-0031-1301314

Abstract This study compared rectal temperature (T re ), heat sensation and sweating between obese and non-obese boys during cycling in the heat. Participants (aged 12–15 years) were 17 obese and 16 non-obese (BMI=29.4±4.3 and 16.8±1.7 kg · m  − 2 , respectively) boys. They cycled for 30-min (50–55% VO 2peak ) in a climatic chamber (35°C, 45% RH) and T re , heat sensation and sweat volume were monitored. From the start to the end of cycling, T re was similar between the obese (37.4±0.3–37.8±0.3°C) and non-obese (37.3±0.2–37.9±0.2°C) groups. Heat sensation was higher in the obese group from the start (3.6±2.7 vs. 1.3±1.4 cm; P=0.008) to the end (7.6±2 vs. 5.2±2.2 cm; P=0.003) of cycling. Sweat volume corrected by body surface area was similar between the obese (200±123 mL · m  − 2 ) and non-obese (212±80 mL · m  − 2 ) groups. Initial and final HR were similar in both groups, and RPE was higher in the obese group at 25 th (P=0.040) and 30 th (P=0.019) min. In conclusion, the obese pubescent participants presented similar T re and sweating volume, but higher heat sensation while cycling in the heat.