Human Factors Assessment of a Pediatric Elliptical Machine With Cost Effective Modifications

Abstract

Background: Developing and sustaining cardio vascular fitness for ambulation are common rehabilitation foci for children with disabilities and their families. Properly designed elliptical trainers may help with pediatric rehabilitation training. Objective: This study focused on the investigation of human factors and ergonomics (HFE) associated with a pediatric elliptical machine, its redesign, and proposing further modifications based on user’s feedback to aid usability, comfort, safety, and interaction. Method: Twenty-eight children(11 typically developing and 17 with physical disabilities and/or chronic conditions) who are 3 to 12 years old, their parents and caregivers, and clinicians participated in the evaluation of the machine before and after modification. Temporospatial data of the children were collected, and their interaction with the machine was assessed. Results: Most features, (i.e., chair height, chair depth, console height, stride length, pedalstraps, and steps height etc.) resulted in positive child and adults’ assessments, whereas six other features resulted in divergent user assessments. Clinicia ns were satisfied with the positioningof chair, stationary handles, pedal, and pedalstraps. However, a lack of adjustability of the stride length was significantly associated with less-than-optimal elliptical training (p = 0.044). Clinicians and 94.3% adult caregivers agreed on the less-than-optimal elliptical training for the children while using the redesigned machine. Conclusion: The modified elliptical machine is a cost effective one and comfortable with im proved safety. A continuously adjustable stride length of 40cm to 110cm was recommended based on kinematic analyses. Additional modifications were suggested to improve the elliptical’s interaction design.