Biomedical subjects

M T Gross

Publications and source records attributed to M T Gross.

23 records · Page 2Linked to original sources

PubMed1990

Validity of knee flexion and extension peak torque prediction models.

The primary purpose of this study was to test the validity of predictive models relating isokinetic knee torque production to anthropometric and demographic variables. Subjects were 23 healthy female and 15 healthy male volunteers between the ages of 10 and 77 years. We measured subjects' peak knee flexion and extension torque production at two angular velocities. For each torque dependent variable, we calculated a Pearson product-moment correlation coefficient between the measured torque values and the values obtained with prediction equations. The difference between the squared value of the correlation coefficients and the regression multiple R2 values obtained for an original group of 134 subjects ranged between .05 and .10 for the torque dependent variables. The results indicate the validity of the regression models at the level specified by the multiple regression R2 values. Clinicians can use the prediction equations presented in this article to establish rehabilitation goals for patients and can estimate the error involved in applying each prediction equation.

Adolescent↗

PubMed1989

Relationship between multiple predictor variables and normal knee torque production.

The purpose of this study was to develop predictive models relating isokinetic knee testing performance to anthropometric and demographic variables. The subjects were 134 healthy volunteers (70 female, 64 male) between the ages of 10 and 80 years. The investigators measured subjects' peak knee flexion and extension torque production at two angular velocities. Stepwise regression analyses were used to examine the relationship between each torque-dependent variable and the following potential predictor variables: age, sex, side of lower extremity dominance, height, weight, percentage of body fat, and thigh girth. The investigators generated two sets of models designed to predict preinjury knee strength. Clinicians can use one set of models by assessing predictor variables before or immediately following injury. The second set of models involves the assessment of predictor variables postinjury, excluding an assessment of percentage of body fat and thigh girth. The results indicated that peak knee torque production can be predicted with statistically significant accuracy (multiple R = .78-.87). The predictive models generated in this study can be used to establish muscle strength goals for patient rehabilitative programs.

Adolescent↗

PubMed1989

Exercise programs for patients with post-polio syndrome: a case report.

Several authors have reported on post-polio syndrome, indicating a decline in muscle strength in individuals years after the onset of poliomyelitis. These reports include suggestions that strenuous exercise programs are contraindicated and may have deleterious effects for patients with post-polio syndrome. The purpose of this case study was to examine the effects of an aggressive, six-week isokinetic exercise program on a 59-year-old patient with post-polio syndrome. Peak torque values were assessed before and during the exercise program, and 6 and 22 weeks following cessation of the exercise program. The results indicate no deleterious effects secondary to the exercise program. The authors suggest future research strategies to investigate the efficacy of exercise programs for patients with post-polio syndrome.

Biomechanical Phenomena↗

PubMed1987

Effects of recurrent lateral ankle sprains on active and passive judgements of joint position.

The purpose of this study was to examine the effects of recurrent lateral ankle sprains on subjects' active and passive judgments of joint position. Fourteen subjects with recurrent unilateral ankle sprains contributed data to two groups: 1) In Group 1, the subjects' 14 sprained ankles were tested and 2) in Group 2, the same 14 subjects' contralateral nonsprained ankles were tested. An additional seven subjects with no history of injury to either ankle comprised Group 3 with 14 nonsprained control ankles. The experimenter tested all blindfolded subjects with active and passive attempts at replicating predetermined ankle joint positions in the inversion-eversion range of motion. An isokinetic dynamometer measured joint position. A two-way analysis of variance indicated no significant effect caused by ankle injury or noninjury. Passive judgments were significantly better than active judgments of joint position (p less than .01) in the nonsprained control group. The results suggest that joint receptors play a dominant role in joint angle detection and that muscle receptors are more valuable in the perception of joint movement.

Adolescent↗

PubMed1985

Thermal denaturation of cytochrome c peroxidase: pH dependence.

Upon heating cytochrome c peroxidase (ferrocytochrome c: hydrogen-peroxide oxidoreductase, EC 1.11.1.5) at pH 4 and 5, the enzyme precipitates at 41 degrees C and 51 degrees C, respectively. Incubating the enzyme at lower temperatures causes a slow dissociation of the heme from the protein. The heme precipitates, while the apoprotein remains soluble. Between pH 6 and 8, the native enzyme is converted to a low-spin ferric form upon heating. The Soret maximum shifts from 408 to 414 nm. The midpoint of this transition is pH-dependent, with a value of 46 degrees C at pH 6 decreasing to 29 degrees C at pH 8. At high temperatures the 414 nm form is converted to a species which has a 'free heme' spectrum with low absorptivity and Soret maximum at 390 nm. The midpoint temperature of this latter transition is 62 degrees C and 57 degrees C at pH 7 and 8, respectively.

Cytochrome-c Peroxidase↗