Inter-rater and intra-rater reliability of isotonic exercise monitoring device for measuring active knee extension

Abstract

Background The goal of this study was to assess the reliability of electromyography and range of motion measurements obtained using a knee exercise monitoring system. This device was developed to collect data on knee exercise activities. Methods Twenty healthy individuals performed isotonic quadriceps exercises in this study. The vastus medialis surface electromyography (sEMG) and range of motion (ROM) of the knee were recorded during the exercise using the isotonic knee exercise monitoring device, the Mobi6-6b, and a video camera system. Each subject underwent a second measuring session at least 24 h after the first session. To determine reliability, the intraclass correlation coefficients (ICCs) and standard error of measurement (SEM) at the 95% confidence interval were calculated, and a Bland–Altman analysis was performed. Results For inter-rater reliability, the ICCs of the mean absolute value (MAV) and root mean square (RMS) of sEMG were 0.73 (0.49, 0.86) and 0.79 (0.61, 0.89), respectively. ROM had an ICC of 0.93 (0.02, 0.98). The intra-rater reliability of the MAV of the sEMG was 0.89 (0.71, 0.96) and the intra-rater reliability of RMS of the sEMG was 0.88 (0.70, 0.95). The ROM between days had an intra-rater reliability of 0.82 (0.54, 0.93). The Bland–Altman analysis demonstrated no systematic bias in the MAV and RMS of sEMG, but revealed a small, systematic bias in ROM (−0.8311 degrees). Conclusion For sEMG and range of motion measures, the isotonic knee exercise monitoring equipment revealed moderate to excellent inter- and intra-rater agreement. However, the confidence interval of ROM inter-rater reliability was quite large, indicating a small agreement bias; hence, the isotonic knee exercise monitor may not be suitable for measuring ROM. This isotonic knee exercise monitor could detect and collect information on a patient’s exercise activity for the benefit of healthcare providers.

Effect of Quadriceps Isometric Exercise on Reducing Pain in Elderly Communities With Knee Osteoarthritis

“…There was a decrease in the number of respondents at the level of pain intensity to ten respondents experiencing moderate pain disorder and five people experiencing mild pain disorder. Contraction in strong quadriceps isometric exercises will facilitate the pumping action mechanism so that metabolic processes can take place properly in local circulation as a result of vasodilation and relaxation after maximal contraction of the muscle (Anwer and Alghadir, 2014;Limsakul et al, 2023). Thus, the transport of metabolic wastes through the inflammatory process can run smoothly so that pain intensity and irritation to the nerves that cause pain can be reduced (Pemaron,2014).…”

“…Isometric quadriceps exercises can trigger the movement of the quadriceps muscles and strengthen the strength of the muscles around the knee (Khosrojerdi et al, 2018;Wirayuni and Arista, 2021). This stimulates the release of endorphins, which can reduce the sensation of pain, and stimulates largediameter type I and II afferent fibers (proprioceptors) so that the activity of these afferent fibers can reduce muscle spasms as well as improve the peripheral circulatory system to reduce pain (Anwer and Alghadir, 2014;Limsakul et al, 2023;Smithard et al, 2022). This type of exercise, especially isometric quadriceps, is recommended for the elderly with osteoarthritis to strengthen muscles and joint mobility, relieve pain, and prevent further deformities (Anzari, 2018;Kangeswari et al, 2021;Syahputra and Nurwijayanti, 2021).…”