Exercise has been shown in numerous studies to improve body composition through reduced adiposity and improved weight control. Increased lean mass causes increased calorie burning. Muscles burn over 90% of the Calories humans consume. Muscle has special enzymes that enable burning of large amounts of calories in short periods. Both exercise and heat exposure cause heat shock and oxidative stress (generation of O2− and H2O2). Both exercise and heat exposure also promote mitochondrial biogenesis which also leads to increased lean body mass. Hyperthermic conditioning has been shown to triple the synthesis of BDNF, and additional studies have shown that BDNF is important for thermogenesis (the ability of cells to burn fat to produce heat) and for controlling appetite and satiety.
A study published in 2003 (1) reported the results of two weeks of sauna therapy for ten obese patients. The study showed that both body weight (84 kg to 82 kg) and body fat (41% to 37%) significantly decreased.
(1)Biro S, Masuda A, Kihara T, Tei C., Clinical implications of thermal therapy in lifestyle-related diseases, Exp Biol Med (Maywood). 2003 Nov;228(10):1245-9.
APL (American Performance Labs) is a research group dedicated to the collection, analysis, and dissemination of published research and articles on the science of hyperthermia and the various applications, technologies and protocols for the use of hyperthermic conditioning.