Far-infrared saunas for treatment of cardiovascular risk factors ; Medical Journal Club article for July 2009:

Far-infrared saunas for treatment of cardiovascular risk factors | Canadian Family Physician Journal -

“Because infrared heat penetrates more deeply than warmed air, users of far-infrared saunas (FIRSs) develop a more vigorous sweat at a lower temperature than users of traditional saunas. The cardiovascular demand imparted by thermoregulatory homeostasis is similar to that achieved by walking at a moderate pace.”

Is the absence of blinded placebo-control groups a limitation of the studies reviewed?