An investigation is reported in which single element semi-conductor and triple element 45° foil rosette strain gauges were attached to the lateral side of the calcaneus in live sheep.

Results from the two types of gauge were similar but those from the rosettes allowed calculations to be made of the changing direction and magnitude of the principal strains and the maximum shear strain during locomotion. This represents a considerable increase in the value and amount of information available from these direct measuring techniques.

Each stride imposed a definite and characteristic deformation cycle on the bone. On its dorsal side this was primarily compressive and identical in direction and timing in all animals.

Strain amplitude and rate of change were comparable to values obtained from other regions in the same species. This agreement tends to support the hypothesis that bone deformation per se may be at least one of the governing stimuli for the remodelling necessary in the maintenance of bone's structure and mechanical strength.