Body integrated wearable electronics can be used for advanced health monitoring, security, and wellness. Due to the complex, asymmetric surface of human body and atypical motion such as stretching in elbow, fi nger joints, wrist, knee, ankle, etc. electronics integrated to body need to be physically fl exible, conforming, and stretchable. In that context, state-of-theart electronics are unusable due to their bulky, rigid, and brittle framework. Therefore, it is critical to develop stretchable electronics which can physically stretch to absorb the strain associated with body movements. While research in stretchable electronics has started to gain momentum, a stretchable antenna which can perform far-fi eld communications and can operate at constant frequency, such that physical shape modulation will not compromise its functionality, is yet to be realized. Here, a stretchable antenna is shown, using a low-cost metal (copper) on fl exible polymeric platform, which functions at constant frequency of 2.45 GHz, for far-fi eld applications. While mounted on a stretchable fabric worn by a human subject, the fabricated antenna communicated at a distance of 80 m with 1.25 mW transmitted power. This work shows an integration strategy from compact antenna design to its practical experimentation for enhanced data communication capability in future generation wearable electronics.

Body‐integrated wearable electronics for health monitoring, security, and wellness applications required flexible, conforming, and stretchable electronics, due to the motion of the human body. On page 6565, J. A. Rogers, A. Shamim, M. M. Hussain and co‐workers develop a helical spring‐based flexible and out‐of‐plane‐stretchable antenna made with copper and showing constant frequency operation for far field communication—demonstrating a major advancement in wearable and implantable electronics.