Biomedical subjects

S D Finucane

Publications and source records attributed to S D Finucane.

7 recordsLinked to original sources

PubMed1998

Reproducibility of electromyographic recordings of submaximal concentric and eccentric muscle contractions in humans.

OBJECTIVES: to determine the intratester and intertester reliability of measures of electromyographic activity (EMG) of submaximal concentric and eccentric contractions and to compare the reliability of normalized and non-normalized measures of EMG. There were 10 subjects, of 22-33 years old. METHODS: Subjects performed submaximal concentric and eccentric contractions at 60 degrees/s, and maximal isometric contractions (MIC) of their knee extensors. The target power of the submaximal contractions was 90%+/-10% of the subject's maximal concentric power. EMG was recorded via bipolar surface electrodes from 3 of the quadriceps femoris muscles. The rmsEMG for submaximal contractions that were within the target power range were determined. The rmsEMG for the submaximal contractions were normalized to the rmsEMG of the maximal isometric contractions. Intraclass correlation coefficients (ICC version 1.1) were calculated to determine intratester and intertester reliability. RESULTS: For non-normalized rmsEMG, ICC values for intratester reliability ranged from 0.62 to 0.91 for concentric and from 0.84 to 0.97 for eccentric contractions. ICC values for intertester reliability ranged from 0.66 to 0.96 for concentric and 0.78 to 0.90 for eccentric contractions. CONCLUSIONS: Non-normalized rmsEMG of submaximal concentric and eccentric isokinetic contractions were found to be reliable. Normalization did not lead to consistently improved reliability.

Adult↗

PubMed1995

Muscular adaptation to concentric and eccentric exercise at equal power levels.

The effect of training with concentric and eccentric contractions on fiber hypertrophy and isometric torque production was investigated in 20 healthy subjects. One group (eight female and two male subjects) performed concentric contractions of their quadriceps femoris muscles at an intensity of 90% of their maximal concentric power. The other group (six female and four male subjects) performed eccentric contractions at the same relative power level. Both groups exercised three times per week for 4 wk at a constant speed of 60 degrees.s-1 on a Kin-Com dynamometer. Needle biopsies were obtained from the vastus lateralis before and after the exercise program. Fiber-type differentiation was performed using a myosin ATPase stain at a preincubation of 10.5. Maximal isometric knee extension torque was also measured before and after the exercise program. An analysis of covariance was used to determine whether there were significant differences between the exercise groups in: 1) the post-exercise fiber areas and 2) maximal isometric torque (MIso), while controlling for initial differences. Results showed a significant difference between the Type II fiber areas (P < 0.01) and the MIso (P = 0.01). These data indicate that, when exercising at the same relative power level, a subject performing concentric contractions will show greater muscle hypertrophy and improve in MIso production more than a subject training with eccentric contractions.

Adaptation, Physiological↗

PubMed1994

Performance characteristics of the Kin-Com dynamometer.

BACKGROUND AND PURPOSE: The purpose of this study was to assess the performance characteristics of a Kin-Com dynamometer (model #500-11) under controlled conditions. METHODS: Comparisons were made between measurements of force, angle, and velocity obtained from the Kin-Com and measurements acquired from an external recording system of known weights, angles, and user-set velocities. The strength of the linear relationships between measurements obtained with the different recording systems was analyzed using a coefficient of determination (r2). An intraclass correlation coefficient (ICC[2,1]) was used to examine the reliability of the force, angle, and velocity measurements obtained with each recording system on 2 different days. RESULTS: In all conditions, the coefficient of determination for the force, angle, and velocity comparisons was above .99. The ICC for between-day comparisons for all force, angle, and velocity measurements was above .99. CONCLUSION AND DISCUSSION: Our results indicate that the static measurements of force and angle that are necessary for use in the gravity-correction procedure and isometric testing are accurate and replicable between days. The Kin-Com dynamometer's control system regulating lever arm velocity is also accurate and replicable under a no-load condition. It was ascertained during the velocity testing that the use of any acceleration and deceleration mode other than "high" resulted in a loss of excursion of the lever arm.

Acceleration↗

PubMed1994

Evaluation of the gravity-correction feature of a Kin-Com isokinetic dynamometer.

BACKGROUND AND PURPOSE: Torques reflecting muscle performance must be corrected for the effects of gravity if error-free ratio-scaled data are to be obtained. Ratio-scaled data are necessary, for example, to report muscle performance characteristics in terms of ratios or percentages or in the form of ratios with another muscle (eg, ratio of hamstring to quadriceps femoris muscle peak torque). The purpose of this study was to determine the error associated with the gravity-correction procedure of the Kin-Com dynamometer when a weight or limb segment is weighed at different lever arm positions. METHODS: A known weight was suspended from the lever arm of the Kin-Com dynamometer. The rotational component of gravitational forces on the weight was measured at 11 different angular positions. We compared the force measurement obtained from the Kin-Com with the predicted rotational component at each angular position. The gravitational forces on a subject's limb segment (leg) were then measured at 12 different angular positions in each of two trunk positions (sitting and supine). We compared the force measurement obtained from the Kin-Com with the predicted rotational component for each position. Forces measured for the two trunk positions with the lever arm horizontal were compared. Forces measured with the knee extended were compared with forces measured with the lever arm horizontal. RESULTS: The dynamometer accurately recorded the rotational component of gravitational forces for the weight suspended from the lever arm. There was a progressively greater discrepancy between measured forces and predicted forces for the leg as the lever arm was moved from horizontal to 50 degrees below the horizontal. The force recorded with the Kin-Com was greater when the subject's knee was in full extension than when the lever arm was horizontal, which placed the subject's knee in a flexed position. A small difference was noted between the measured forces with the lever arm horizontal when the subject was sitting compared with when the subject was positioned supine. CONCLUSION AND DISCUSSION: When weighing a leg with this dynamometer, we recommend that the lever arm be as close to the horizontal position as possible. Positions of proximal joints should be chosen that do not put two joint muscles in stretched positions.

Adult↗

PubMed1989

Intrasession and intersession reliability of hand-held dynamometer measurements taken on brain-damaged patients.

Recent reports have characterized force measurements obtained with hand-held dynamometers from brain-damaged patients as being highly reliable. The purposes of this two-part study were to replicate essential parts of those studies and to further examine the reliability of these measurements in a clinical context. Repeated force measurements were taken from the nonparetic and paretic limbs of brain-damaged patients during the same testing session (Part 1) and during two testing sessions separated by two days (Part 2). The intratester intraclass correlation coefficients (ICCs) for all measurements taken during a single session ranged from .88 to .98. The ICCs for repeated measurements taken two days apart from the paretic limbs ranged from .90 to .98. The ICCs for repeated measurements taken two days apart from the nonparetic limbs ranged from .31 to .93. The ICCs for repeated measurements taken two days apart from the combined data for all limbs ranged from .79 to .97. Hand-held dynamometer measurements taken on brain-damaged patients appear to be highly reliable when taken during the same testing session. When repeated measurements are separated by a longer time interval, the measurements taken from the paretic limbs continue to be highly reliable, whereas most measurements taken on the nonparetic limbs exhibit poor reliability.

Adult↗

PubMed1988

Reliability of isometric muscle testing of knee flexor and extensor muscles in patients with connective tissue disease.

This two-part study evaluated the reliability of inexpensive devices for isometric muscle testing on patients. First, the relationship between gauge readings of the devices and known weights was evaluated. Coefficients of determination and regression lines were used to determine the strength and nature of this relationship, which was determined to be linear. Second, intratester reliability for force measurements of isometric knee extension and flexion motions was determined for 30 patients with connective tissue diseases. Right knee extensor and flexor muscle forces were measured during two sessions. The measurements between sessions were compared for degree of agreement using intraclass correlation coefficients. Intraclass correlation coefficients ranged from .90 to .95 for knee flexor force measurements and from .75 to .85 for knee extensor force measurements. Based on the results of this study, this measuring device can be used reliably to measure knee extensor muscle force at 50 degrees and knee flexor muscle force at 30 and 70 degrees.

Adolescent↗

PubMed1987

Relationships between lumbar lordosis, pelvic tilt, and abdominal muscle performance.

The purpose of this study was to examine the relationships between measurements of lumbar lordosis, pelvic tilt, and abdominal muscle performance during normal standing. In addition, the reliability of the measurements used in this study was examined. Measurements of lumbar lordosis, pelvic tilt, and abdominal muscle performance were taken of 31 healthy adults aged 20 to 33 years. Each measurement was taken twice, and the measurements were shown to be reliable. The Spearman's rho correlation of the abdominal muscle performance measurements with pelvic tilt was .18 and with lordosis was .06. The Pearson product-moment correlation of lordosis with pelvic tilt was .32. The results indicate that lumbar lordosis, pelvic tilt, and abdominal muscle function during normal standing are not related. This study demonstrates the need for a reexamination of clinical practices based on assumed relationships of abdominal muscle performance, pelvic tilt, and lordosis.

Abdominal Muscles↗