Using skin resistance measurements to determine timing of bio-telemetry measurements

A wearable device comprising:

• a housing;
• a user interface disposed on an outside surface of the housing;
• a mount configured to mount the housing to a first external body surface;
• a first electrical contact disposed on the housing, wherein the first electrical contact is configured to contact skin at the first external body surface when the housing is mounted on the first external body surface, wherein the first external body surface is a wrist location of a first arm of a wearer;
• a second electrical contact disposed on the housing, wherein the second electrical contact is configured to contact skin at the first external body surface when the housing is mounted on the first external body surface;
• a third electrical contact disposed on the housing, wherein the third electrical contact is configured to be contacted by skin of a second external body surface, wherein the second external body surface is a location of a second arm of the wearer;
• and
• a controller, wherein the controller is configured to perform controller operations comprising:
• detecting an impedance between the first and second electrical contacts;
• determining whether the detected impedance is less than a specified threshold;
• responsive to determining that the detected impedance is less than the specified threshold, providing an indication via the user interface;
• and
• subsequent to providing the indication via the user interface, detecting a voltage between the first electrical contact and the third electrical contact.