An apparatus comprises a flexible filament structure, and a fiber optic sensor with a buffer material that locally bonds the fiber optic sensor to the flexible filament structure to create a bond between the fiber optic sensor and the flexible filament structure to transfer strain from the flexible filament structure to the fiber optic sensor to allow the fiber optic sensor to detect strain on the flexible filament structure while maintaining flexibility in the flexible filament structure. A fiber optic interrogator may be optically coupled to the fiber optic sensor and configured to measure strain. A method comprises embedding a fiber optic sensor with a buffer material in or on a flexible filament structure. Thereafter, the buffer material is activated via heating or curing to locally adhere the fiber optic sensor to the flexible filament structure to create a local bond. The local bond transfers strain from the flexible filament structure to the fiber optic sensor.