Which statement best describes the role of the return electrode in NMES?

• A. It is optional and may be omitted in some cases.
• B. It should be placed far from the treatment site to avoid current.
• C. It has no effect on current distribution.
• D. It completes the circuit, helps distribute current, and improves contraction localization while reducing skin irritation.

Answer: (D)

In NMES, current flows from the active electrode through the body and back via the return electrode, so the return electrode is essential because it completes the electrical circuit. Its size and placement shape the path the current takes, which affects which muscles are activated and how localized the contraction will be. A larger return electrode spreads the current over more skin, reducing current density and skin irritation, while positioning it to steer the current through the target muscle group improves selectivity. Placing it far away merely to “avoid” current can lead to less predictable paths and poorer contraction localization.