A method of measuring healing strength of bone includes a bone fixation plate (14) implanted at the healing area between bone segments (12). The bone fixation plate (14) includes high aspect ratio material with electric current conduction properties responsive to strain. This method causes an induced, or directly applied, electric current to pass through the high aspect ratio material. Analysis of the change in this current by a series of increasing loads placed on the healing body part indicates what level of load produces strain on the bone fixation plate (14). As healing strength increases, evidence of strain on the bone fixation plate (14) occurs at a greater load. Physicians determine thereby the strength of bone healing and safe levels of activity for patients while bone healing progresses.