Final answer:
Indirect High Frequency Current in massage therapy primarily amplifies massage effects to enhance relaxation and aid in the penetration of skincare products.
Step-by-step explanation:
Indirect High Frequency (HF) Current is essentially applied to amplify the effects of massage movements to enhance relaxation and stimulate the healing processes in tissue. Its primary function in massage therapy, contrary to superficial heating treatments like microwave diathermy that penetrate deeper into tissue, involves promoting circulation, aiding in relaxation, and potentially assisting with the penetration of skincare products through heat and increased molecular activity. High-frequency treatments can indirectly affect the skin's surface and underlying layers to improve the overall health and appearance of the skin, but the specific effect of amplifying massage movements through High Frequency for relaxation aims more towards improving penetration of the products used during treatment.