A shoe or other footwear has a non-removable multi-layer insole. A middle layer of the insole has apertures that define several discrete storage chambers within the insole. Each storage chamber stores a mixture of particulate or granular materials, such as sand, powdered titanium, powdered aluminum, powdered talcum, powdered zinc. The insole or footwear further includes integrated components such as: electromyogram (EMG) sensors, temperature sensors, pressure sensors, humidity sensors, sweat sensors. The insole or footwear further includes integrated stimulating units, such as: Transcutaneous Electrical Nerve Stimulation (TENS) units, electrodes, infrared radiation units. Data is sensed by the sensors integrated in the insole or footwear, in response to a human foot stepping on the discrete storage chambers that store the particulate or granular materials, and optionally in response to stimulation operations. Data is processed to detect or estimate a medical condition, and to selectively modify operational properties of the stimulation units.