NONAN GaitPrint: An IMU gait database of healthy middle-aged adults

Despite comprising approximately 25% of the total U.S. population and 41% of its workforce in 2023, middle-aged adults (whom we define as 36-55 years) face a stark disparity between their demographic representation and the available research data dedicated to them. This dataset contributes to addressing that gap as the final addition to the Nonlinear Analysis Core (NONAN) GaitPrint database, focusing specifically on middle-aged adults. Designed to complement our previously published datasets on young and older adults using an identical protocol, this dataset includes full-body inertial measurement data during self-paced overground walking on a 200 m indoor track of 50 middle-aged adults (36-55 years old; 21 men and 29 women; age: 46.1 ± 5.9 years; height: 173.43 ± 8.42 cm; body mass: 87.14 ± 18.87 kg) collected across 18 four-minute trials conducted over two days. Exhaustive documentation, subject and trial characteristics, supplementary code, and results accompany the dataset. The technical validation comprises five distinct analyses, comparative assessments with existing literature, and interpretative insights into the findings.