Novel stretch-sensor technology allows quantification of adherence and quality of home-exercises: a validation study

OBJECTIVE: To investigate if a new stretch sensor attached to an elastic exercise band can assist health professionals in evaluating adherence to home exercises. More specifically, the study investigated whether health professionals can differentiate elastic band exercises performed as prescribed, from exercises not performed as prescribed. METHODS: 10 participants performed four different shoulder-abduction exercises in two rounds (80 exercise scenarios in total). The scenarios were (1) low contraction speed, full range of motion (0-90°), (2) high contraction speed, full range of motion (0-90°), (3) low contraction speed, diminished range of motion (0-45°) and (4) unsystematic pull of the elastic exercise band. Stretch-sensor readings from each participant were recorded and presented randomly to the raters. Two raters were asked to differentiate between unsystematic pull (scenario 4), from shoulder abduction strength exercises (scenarios 1-3). The next two raters were asked to identify the four different exercise scenarios (scenarios 1-4). RESULTS: The first two raters were able to differentiate between unsystematic pull (scenario 4) from shoulder abduction strength exercises (scenarios 1-3). They made no errors (100% success rate). The second two raters were both able to identify each of the 80 scenarios (scenarios 1-4). They too made no errors (100% success rate). CONCLUSIONS: The stretch-sensor readings from the elastic exercise band allow health professionals to quantify whether strength-exercises have been performed as prescribed. These findings have great implications for future clinical practice and research where home exercises are the drugs-of-choice, as they enable clinicians and researchers to measure the exact adherence and quality of the prescribed exercises.