Isokinetics and Exercise Science - Volume 2, issue 3

Authors: Brown, Lee E. | Whitehurst, Michael | Bryant, Jennifer R.

Article Type: Research Article

Abstract: The purpose of this study was to compare the tibial control system (TCS) and sliding cuff (SC) lever arms in the strength parameters peak torque (PT), average work (AW), average power (AP), joint angle at peak torque (JA), and fatigue index (FI). Fifteen healthy subjects, with no history of knee pathology, performed three knee extension/flexion repetitions using the right leg at a velocity spectrum of 60, 180, 240, and 20 repetitions at 300 deg/sec for each lever arm. TCS and SC were randomly presented with 24 hours between conditions. Significance was set at p < 0.05. Paired t tests showed …that the SC produced significantly greater PT, AW, and AP than the TCS during extension across velocities. Also, SC JA occurred significantly later in the range of motion across velocities, whereas FI was significantly greater for the SC than the TCS at 300 deg/sec. Paired t tests for flexion data indicated that the TCS produced significantly greater PT than the SC across velocities and greater AP at 60 deg/sec. The SC condition resulted in significantly greater AW and AP at 300 deg/sec only. The SC and TCS conditions did not differ for JA and FI across velocities. It was concluded that choice of lever arm significantly influenced the strength parameters examined in this study. Show more

Keywords: LIDO sliding cuff, tibial control system, isokinetic assessment

DOI: 10.3233/IES-1992-2301

Citation: Isokinetics and Exercise Science, vol. 2, no. 3, pp. 101-109, 1992

Authors: Wagner, Loree L. | Housh, Terry J. | Weir, Joseph P. | Johnson, Glen O.

Article Type: Research Article

Abstract: The purpose of this investigation was to determine if there are gender differences in the isokinetic torque-velocity curves constructed from peak torque (PT) and constant joint angle (i.e., angle-specific torque) (CJA) torque values for leg flexion and extension. Ten female and ten male university students performed leg extension and flexion movements at velocities of 0, 48, 96, 144, 192, 240, and 288 deg/sec (zero, 0.84, 1.68, 2.51, 3.35, 4.19, and 5.03 rad/sec) on a Cybex II isokinetic dynamometer. The results indicated that the plateau in CJA torque output for the men extended from 0 to 192 deg/sec (0–3.35 rad/sec) for …leg extension and 0 to 96 deg/sec (0–1.68 rad/sec) for leg flexion. For the women, the torque plateau extended from 0 to 144 deg/sec (0–2.51 rad/sec) for leg extension and 0 to 48 deg/sec (0–0.84 rad/sec) for leg flexion. For both CJA and PT output, the men showed a smaller percent decline (relative to maximal values) than the women with increasing velocities. These findings support the presence of gender differences in the PT and CJA torque-velocity relationships for leg extension and flexion. Show more

Keywords: Gender differences, peak torque, constant joint angle

DOI: 10.3233/IES-1992-2302

Citation: Isokinetics and Exercise Science, vol. 2, no. 3, pp. 110-115, 1992

Authors: Fiebert, Ira M. | LeBlanc, William G. | McGuane, Sheila A. | Schnoes, Cynthia D. | Strickland, Kathryn M.

Article Type: Research Article

Abstract: We examined the relationship between the vastus medialis oblique (VMO) and the vastus lateralis (VL) during maximal isometric knee extension contractions by measuring force and electromyographic (EMG) activity of the two muscles at 45 and 90 deg of knee flexion. Testing involved three maximal isometric contractions at the two positions for 27 subjects (50 legs). Recordings of average EMG and force output were measured by the Bio-Prompt 3000 and the FARO Axis Muscle Tester, respectively. The results showed these statistically significant differences pertaining to EMG activity: (1) greater VL at 45 deg for the whole sample; (2) greater VMO and …VL in males at 45 deg; (3) greater VMO in females at 90 deg; (4) greater VMO and VL in males than in females at 45 deg; and (5) a correlation of VMO and VL in females at 45 deg. These results demonstrate that sex differences exist in EMG activity between the VMO and VL at two angles of knee extension. Show more

Keywords: Electromyographic/force relationships, vastus medialis/lateralis, isometric contractions

DOI: 10.3233/IES-1992-2303

Citation: Isokinetics and Exercise Science, vol. 2, no. 3, pp. 116-123, 1992

Authors: Capuano-Pucci, Donna | Clifford, Jeff A. | Gillan, Matthew D. | Pleva, David J. | Seiler, Jason S.

Article Type: Research Article

Abstract: The purpose of this study was to determine the effect of different body positions on the force generated by elbow flexor and extensor muscles. The Nicholas Manual Muscle Tester, a hand-held dynamometer, was used to measure the force generated by the muscles. A random sample of 28 healthy subjects was tested by a single examiner. Each muscle group was tested with gravity eliminated and with the subjects sitting and supine. The dynamometer was positioned on the extremity and a break test was performed. The data were analyzed using the two-way analysis of variance for repeated measures. A significant difference in …the force generated by the muscles was noted between positions (p < 0.05) for both elbow flexors and extensors. Alterations in body position appear to influence the amount of force generated by the elbow flexor and extensor muscles. Show more

Keywords: Muscle force, dynamometer, gravity-eliminated body positions

DOI: 10.3233/IES-1992-2304

Citation: Isokinetics and Exercise Science, vol. 2, no. 3, pp. 124-128, 1992

Authors: Hills, Morgan | Bohannon, Richard W.

Article Type: Research Article

Abstract: The primary purpose of this study was to determine if shoulder extension strength is influenced by elbow position (flexed versus extended). Secondary purposes were to describe the affects of gender, arm dominance, and trial on shoulder extension strength. Thirty subjects (14 men, 16 women) with no pathology of the upper extremities participated. They performed with each extremity in a random order two trials of maximum voluntary shoulder extension with the elbow flexed versus extended. Shoulder strength measurements were obtained with a hand-held dynamometer. A 2 × 2 × 2 × 2 analysis of variance showed that elbow position, gender, arm …dominance, and trial all had significant effects. Because shoulder extension strength is greater with the elbow flexed and because subjects with some pathologies are unable to perform shoulder extension with the elbow extended, we recommend the elbow flexed position. Show more

Keywords: Shoulder extension, elbow position, hand dynamometer

DOI: 10.3233/IES-1992-2305

Citation: Isokinetics and Exercise Science, vol. 2, no. 3, pp. 129-132, 1992

Authors: France, E. Paul | Derscheid, Gary | Irragang, Jay | Malone, Terry | Petersen, Roger | Tippett, Steve | Wilk, Kevin

Article Type: Research Article

Abstract: A multicenter study was conducted to characterize the effects of balance therapy using the Kinesthetic Ability Training (KAT.) balance board on static balance in healthy, uninjured individuals. The results of this preliminary study demonstrated that individuals who participated in a balance training group were able to improve their static balance ability after a six-week training period in comparison to a control group.

Keywords: Functional proprioception, balance ability, K.A.T. system

DOI: 10.3233/IES-1992-2306

Citation: Isokinetics and Exercise Science, vol. 2, no. 3, pp. 133-139, 1992

Authors: Herlant, M. | Delahaye, H. | Voisin, Ph. | Bibre, Ph. | Adele, M.F.

Article Type: Research Article

Abstract: Plantar flexors (PF) of sixty-two patients were tested on the Cybex II Dynamometer about three weeks after anterior cruciate ligament (ACL) surgery. Compared to the non-injured extremity, the deficit is in the range of 30–40%. The authors emphasize the important role of the PF in the stability of the knee and thus the need to reinforce them in a comprehensive program of rehabilitation after ACL surgery.

Keywords: Ankle plantar flexors, ACL surgery, torque comparisons

DOI: 10.3233/IES-1992-2307

Citation: Isokinetics and Exercise Science, vol. 2, no. 3, pp. 140-144, 1992