Sensor nodes containing pairs of temperature and humidity sensors were assessed as a mean of garment performance and comfort studies. Modern sensors are small, low weight and produce minimal disturbance when placed under the garments and in the footwear. Four sensor nodes were used to provide dynamic information about heat and humidity transfer properties of garments during the tests in realistic conditions. Pilot studies were carried out for the few models of cross country skiing garments and waders. Main studies were carried out in the wind tunnel at Mid Sweden University having pivoted treadmill, temperature control and rain capacity. Additional experiments with the waders were carried out in a large water tank. Studies of the temperature and humidity dynamics under the garments containing microporous membranes illustrate the importance of recognizing main features of such materials. In particular, such membranes can only transport moisture from the side where humidity is higher. It means that garments and footwear containing such membranes will potentially behave differently when ambient air humidity changes. In particular, modern garments with incorporated microporous membranes being superior at low ambient air humidity can be dramatically less effective for moisture transfer from the body in the rain.