Biomedical subjects

A Kozma

Publications and source records attributed to A Kozma.

At least 19 recordsLinked to original sources

PubMed1991

Age, activity, and physical performance: an evaluation of performance models.

Two performance models relating age, physical activity, and physical performance were evaluated on 5 age cohorts involving more than 6,000 persons ranging in age from 20 to 69 years. Significant age and activity main effects, without 1 Age X Activity interaction, were obtained on 5 fitness measures and 2 activity indexes. These results are inconsistent with predictions from the moderation model, but they fit predictions from a recently formulated tonic and overpractice model of physical performance.

Activities of Daily Living↗

PubMed1989

Age, exercise, and coding performance.

We investigated the effects of exercise on the coding performance of young and older subjects. Hypotheses were tested that exercise either facilitates spatial localization or reduces susceptibility to distraction in older subjects. In a balanced design, we administered Digit Symbol and Symbol Digit coding tasks to exercisers and nonexercisers at two age levels under conditions of low or high within-task interference. The findings showed higher performance by the exercisers than by the nonexercisers only at the older age level and only with the Symbol Digit task. These findings support the hypothesis that exercise compensates for a loss of spatial localization skills with age. We found no evidence that susceptibility to distraction either increased with age or was affected by chronic exercise.

Adult↗

PubMed1989

The prediction of mortality in elderly institution residents.

The relationship between activity and mortality has been examined mainly in middle-aged and elderly community residents. This study investigated the prediction of five-year mortality in 156 institution residents, including a subsample (n = 121) retested one year after the initial assessment. The measures included demographic variables, three health indexes, happiness, quality of life ratings, personality and life stress indexes, cognitive function, and activity level. The strongest predictors of survival beyond five years from initial testing were a younger age and a high activity level. The relationships of age and activity to survival were mutually independent and were not secondary to the effects of any other variable. Health was not related to activity level and did not emerge as a strong predictor of survival. After a consideration of methodological issues, the findings were interpreted as providing support for an activity theory formulation of mortality prediction.

Activities of Daily Living↗

PubMed1989

Effects on mood of a life-styles program for the rehabilitation of injured workers.

This study reports an examination into the effects on daily mood of participation in a life-styles program by injured workers. In the current prospective study, 14 participants completed the Memorial University Mood Scale (MUMS) prior to starting the program, at 1 month, 2 months, and at 3 months. They also completed the Memorial University Scale of Happiness (MUNSH) prior to entry and after three months. There were significant improvements on the MUMS subscales of positive mood and vigor as well as overall mood. There were no changes in negative mood. Neither the positive nor the negative dispositional subscales of the MUNSH revealed any change. The results were interpreted as indicating strong psychologic benefits of the life-styles program for injured workers and are also consistent with a recently proposed two-factor state/trait model of well-being.

Adult↗

PubMed1987

Social desirability in measures of subjective well-being: a systematic evaluation.

The present investigation addressed the problem of a social desirability response bias in measures of psychological well-being. Data on 150 people, between the ages of 50 and 82, yielded high correlations between three measures of well-being (the MUNSH, the LSI-Z, and the PGC) and the Edwards Social Desirability Scale, but only moderate ones between well-being scales and the Marlowe-Crowne Social Desirability Scale. Part correlations between well-being measures and an external criterion of happiness, controlling for social desirability, failed to improve on the zero-order criterion/well-being relationship. Controlling for social desirability, therefore, does not enhance the construct validity of well-being scales. These and related results suggest that the high zero-order correlations between measures of well-being and the Edwards scale are more readily attributed to content similarity between the Edwards scale and measures of well-being than to a social desirability response bias in well-being measures.

Aged↗

PubMed1987

Balance and age in the sighted and blind.

This study evaluated the usefulness of a balance test with eyes open and closed to index postural control capability. Experiment 1 was a one-year longitudinal study of 225 subjects aged 50 to 82 years. Comparing the two conditions, balance with eyes open had higher reliability, had greater sensitivity to aging effects, correlated stronger with functional age indices (vital capacity and forced expiratory volume), and showed greater sensitivity to the effects of physical fitness training. Experiment 2 included 22 visually impaired subjects aged 19 to 84 years. Minimally sighted subjects balanced for longer than fully blind subjects, but no differences in balance were found between subjects blind from birth versus those with acquired vision loss. The findings demonstrate the importance of vision to balance and indicate that balance with eyes open is a valid and sensitive test for clinical and research purposes.

Aged↗

PubMed1986

Age by distance effects in running and swimming records: a note on methodology.

Running and swimming records by Masters athletes provide useful data for appraising age trends in physical performance; however, different forms of analysis have yielded conflicting conclusions about whether the deterioration with age is greater on sprint events or longer events. Aspects of analytic procedure that have contributed to the conflict include the use of time or velocity as the dependent variable, and the expression of age trend as relative or absolute change. An evaluation of underlying issues showed that meaningful inferences can be derived either where relative age change is compared across events, or the dependent variable is transformed to a logarithmic scale for purposes of comparing absolute change across events. Confounding of variables is introduced if absolute change in velocity is analyzed with respect to both age and event. The conclusion from every analysis in the literature that permits meaningful inference is that deterioration with age is greater on events of beyond sprint distance.

Aging↗

PubMed1986

Age trends in maximal physical performance: comparison and evaluation of models.

Versions of five paradigmatic models of age change in maximal physical performance were compared with respect to internal and validational data. The models were termed power output, power supply, energy output-supply, motivation, and sampling. The power output models tended to be more stringent in terms of internal criteria. The model that best predicted the validational data (i.e., from studies of reaction time, strength assessment, and athletic records) was from the energy output-supply category. This model, the power output relative to power available (POrPA) model, postulates that deterioration with age in physical performance varies with the ratio of peak power output to available power: the numerator generally varies with the strength demands of the task, and the denominator varies with task duration at high power output. The implications of this model were discussed with respect to habitual physical performances in later life.

Adult↗

PubMed1986

"Happy are they who are happy . . ." a test between two causal models of relationships between happiness and its correlates.

The intention of the study was to test between two causal models of relationships between happiness and five of its correlates (i.e., housing satisfaction, financial satisfaction, perceived health, locus of control, and activity level). In Model 1, happiness was identified as a propensity variable that is a source of influence on the lower order correlates. Model 2 is a traditional formulation whereby levels of happiness are determined by its correlates. The models were tested by causal modeling procedures, using 18-month longitudinal data from 408 elderly subjects. The findings support Model 1 over Model 2 for 17/18 predictions that differentiated the models. The status of happiness as a trait was discussed with reference to: the type of items included in the happiness scale; and relationships with variables not included in the research.

Aged↗

PubMed1986

Happiness and activities as propensities.

The research proceeded in two stages. The intention at the first stage was to develop a comprehensive activities inventory (i.e., the Memorial University of Newfoundland Activities Inventory, or MUNAI) that reflected recurrent content themes in interview data obtained from elderly adults. The intention at the second stage was to test a reactivity model and a propensity model of happiness-activity relationships in an 18-month longitudinal design. The reactivity model asserts that happiness, in part, is determined by activity levels. The claim of the propensity model is that both happiness and activity indices are reflections of different underlying propensities. The results supported the propensity model in that (a) activity structure retained stability over the longitudinal interval, (b) the relative standing of individuals on both happiness and the structural activity indices retained stability and, (c) the happiness-activities relationship was of a limited order.

Activities of Daily Living↗

PubMed1977

Effects of concurrent verbal and musical tasks on a unimanual skill.

Subjects balanced a dowel rod on the right or left index finger while speaking, while remaining silent, and while humming a melody. In males balancing times for the right hand decreased with concurrent verbalization. Verbalization had no effect on left hand performance in males, nor on either hand in females. Concurrent humming had no effect on performance of males or females. Poorer right hand performance by males when verbalizing is attributed to interference with right-sided motor control by the left hemisphere due to verbal activity programmed by the same hemisphere. Unimpaired right hand performance in verbalizing females suggests that the language function is less clearly lateralized in females than in males. The possibility that music may be shared by both hemispheres is discussed.

Adult↗

PubMedDate not supplied