Stress and anxiety
The stress reaction is also known as the "fight-flight-or-freeze response".
When the brain feels danger, immediate physiological responses ensure that the body can react to the situation. Responses such as an increased heart rate, constricted blood vessels, tensed muscles, adrenaline rush. Some essential functions are put on hold such as the immune system, the reproductive system, the digestive system. If those survival reactions persist beyond the time necessary to "flee the tiger, knock him out or play dead" these mechanisms give rise to physical and psychological discomfort: symptoms of stress.
The simple act of touching and massaging the feet creates a feeling of well-being. The "rest and digest" response tells the body it is safe to focus on recovery. Endorphins -the body's natural pain relievers- are released. Functions like digestion are supported, and wastes are eliminated.
The reflexology map refers to specific areas in the foot related to the parasympathetic system (responsible for the "rest and digest response"). The brain for example situated in the big toe. The diaphragm that relaxes breathing, located just under the ball of the foot. The solar plexus or the adrenal gland that generates the stress hormones.
Many emotional and physical symptoms are related to stress.