Reliability of the Isoacceleration Mode of the LIDO Active

Article type: Research Article

Authors: Grubbs, Nathaniel^{*; **; ***} | Taggart, Iris^{****; *****} | Wyatt, Barbara^{******; *******}

Note: [*] Instructor, Department of Physical Therapy, University of Central Arkansas, Conway, AR

Note: [**] Physical Therapist, Physical Therapy Department, University Hospital of Arkansas, Little Rock, AR.

Note: [***] Address reprint requests to Nathaniel Grubbs, MHS, PT, 14 Cottontail Drive, Conway, AR 72032.

Note: [****] Physical Therapist, Physical Therapy Department, University Hospital of Arkansas, Little Rock, AR.

Note: [*****] Graduate students in the Master's Degree program in the Department of Physical Therapy, University of Central Arkansas, Conway, AR.

Note: [******] Graduate students in the Master's Degree program in the Department of Physical Therapy, University of Central Arkansas, Conway, AR.

Note: [*******] Physical Therapist, Department of Rehabilitation, Baptist Rehabilitation Institute, Little Rock, AR.

Abstract: Exercise consisting of muscle actions performed against an accommodating resistance at a linear rate of acceleration is provided via the isoacceleration mode of the LIDO Active dynamometer. Theoretically, these controlled concentric accelerative movements and eccentric decelerative movements more accurately reflect real-life muscular conditions than conventional isokinetic movements. The purpose of this study was to determine the concentric and eccentric reliability of the isoacceleration mode of the LIDO Active dynamometer at two rates of acceleration: 180 and 500 deg/sec/sec. Thirty normal subjects (mean age = 28.8 ± 5.66 years) participated. The quadriceps muscle group of the dominant lower extremity was tested on three occasions over a 3-week period, with at least 48 hours but no more than 7 days separating test sessions. After a 5-minute warm-up consisting of stationary cycling, five maximal effort concentric and eccentric quadriceps contractions were recorded at each rate of acceleration during the last two test sessions. The first session was used as a learning trial and data were not utilized. Total work performed was collected and divided by the number of repetitions to yield average work per repetition. An analyses of variance showed no significant differences between corresponding values obtained across the test sessions, indicating reliability. An intraclass correlation coefficient (ICC 1, 1) was then calculated to determine the level of reliability of measures. The ICC for concentric and eccentric contractions at 180 deg/sedsec was 0.96 and 0.89, respectively. The ICC for concentric and eccentric contractions at 500 deg/sec/sec was 0.92 and 0.86, respectively. These results indicate high reliability of the isoacceleration mode of the LIDO Active dynamometer in a test-retest situation at the acceleration rates investigated for the quadriceps femoris. The establishment of sufficiently high reliability allows for continued research into the efficacy of controlled isoaccelerative exercise.

Keywords: isoacceleration, reliability, concentric and eccentric patterns

DOI: 10.3233/IES-1994-4103

Journal: Isokinetics and Exercise Science, vol. 4, no. 1, pp. 13-18, 1994