What is a common sign of poor electrode contact, and how can impedance issues be troubleshooted?

• A. Inadequate current delivery or inconsistent sensations; troubleshoot by cleaning skin, reapplying gel, repositioning electrodes, ensuring full contact, and replacing pads if needed
• B. Immediate strong muscle contraction; adjust to higher intensity
• C. No sensation and a tingling feeling; stop treatment
• D. Excessive sweating; change to different modality

Answer: (A)

Impedance at the skin-electrode interface controls how much current actually gets to the tissues. A common sign of poor electrode contact is inadequate current delivery or inconsistent sensations, because high impedance at the contact points disrupts the steady flow of current and makes the user feel patchy or unreliable stimulation.

To troubleshoot impedance issues, start with the basics: clean the skin to remove oils and debris, dry the area if needed, and refresh or reapply conductive gel. Reposition the electrodes so they sit flat and firmly against the skin, ensuring full contact without hair or folds under the pads. Inspect the pads themselves—replace them if they’re worn, damaged, or gel has dried out. Make sure there’s no gel bridging between pads or pooling that could alter current paths, and verify proper pad placement and skin preparation.

If impedance remains high, consider using a different pad type or more conductive gel, and check device settings or the impedance readout if available.

Other options describe different scenarios (such as responses driven by intensity, sensation quality, or modality changes) that aren’t specifically about poor contact at the skin-electrode interface.