Related to the amount of body water. Since more water is stored in fat-free mass, a higher value indicates healthier leaner tissue.
Resistance is the effect on an alternating current that is caused by the energy dissipating the tissues of the body. Resistance is measured directly from the human body by the bioimpedance analyzer. A low resistance is consistent with large amounts of fat free mass. A high resistance is consistent with low amounts of fat free mass.
Resistance is related to water in the body. Electrolytic fluid consisting of water and charged ions contained in the body’s fat free mass readily conducts electrical current. Extracellular fluid (water and ionized sodium Na+) provides a low resistance pathway. Intracellular fluid (water and ionized potassium K+) also provided a low resistance pathway. Low resistance, indicating high conductivity, is due to large amounts of water in the body. Since water is contained solely within fat-free mass, resistance in the body is proportional to the amount of fat free mass.