Search

Background and Purpose During the aging process, older adults may experience a loss of strength and power, which then may lead to functional limitations and disability. The purpose of this study was to examine how impairments in lower-extremity strength and power are related to functional limitations and disability in community-dwelling older adults. Subjects Thirty older adults (age [X̅±SD], 77.3±7.0 years; 25 women and 5 men) with mild to moderate functional limitations participated in this study. Methods Lower-extremity strength, peak power, power at a low relative intensity, and power at a high relative intensity were measured with a pneumatic resistance leg press. Functional limitations and disability were assessed with the Short Physical Performance Battery (SPPB), the Six-Minute Walk Test (SMWT), and the Late Life Function and Disability Instrument (LLFDI). Results All measures of strength and power were related to functional limitations. Peak power demonstrated the strongest relationships with SMWT, the SPPB gait speed subscale, and the LLFDI functional limitation component. Power at a high relative intensity demonstrated the strongest relationships to the SPPB total score and the SPPB sit-to-stand subscale score. All measures of strength and power were indirectly related to the LLFDI disability component. Discussion and Conclusion Older adults should focus on increasing and maintaining lower-extremity strength and power across a range of intensities in order to decrease functional limitations and disability.

This study was designed to evaluate the Scoliometer®, an instrument that measures axial trunk rotation in individuals with scoliosis. The objectives included determining 1) the Scoliometer's® screening capability and validity and 2) the intrarater and interrater reliability of Scoliometer® measurements. Scoliometer® measurements made by two raters on 65 persons with idiopathic scoliosis were correlated with radiographic assessment of vertebral (pedicle) rotation and lateral curvature (Cobb method). Correlations ranged from .32 to .46 with pedicle rotation and from .46 to .54 with the Cobb angle. Frequency analysis revealed relatively good specificity, sensitivity, and predictive capability of the Scoliometer®. Intrarater and interrater reliability coefficients were high ( r = .86–.97). These results indicate good measurement reproducibility. The less-than-optimal between-method correlation coefficients suggest that the validity of Scoliometer® measurements is not sufficient to use this method alone for determining patient diagnosis and management. Based on the positive-frequency analysis, however, the use of this tool as a screening device would be appropriate.

This study evaluated the oxygen consumption (VO2) and heart rate response curves for standardized upper- and lower-extremity exercise on land and in water. Forty healthy subjects performed one upper-extremity and one lower-extremity exercise at three selected cadences on land and in water. Steady-state heart rate was determined by electrocardiographic radiotelemetry and expressed as a percentage of age-predicted maximal heart rate (% APMHR). Percentage of age-predicted maximal heart rate was used as the criterion measure of relative exercise intensity. Oxygen consumption was determined by the open-circuit method. Results indicated systematic increases in VO2 from 2 to 9 metabolic equivalents (METs) (1 MET = 3.5 mL O2.kg-1.min-1) and % APMHR from 45% to 73% with increased cadence. The VO2 responses were highest during water exercise, whereas % APMHR was greater during land exercise. Based on the magnitude of the responses, water calisthenics appear to be of sufficient intensity to elicit training adaptations. Training studies are needed to document these changes.

The purpose of this study was to investigate differences in selected biomechanical and physiological measurements and subjective preferences for ambulation with the standard single-tip axillary crutch versus the rocker-bottom-type axillary crutch. Self-selected walking velocities (S-SWVs) and stride length for each crutch type were determined for a two-point, non-weight-bearing, swing-through gait in 24 healthy volunteers. Relative exercise intensity, oxygen uptake (VO2), and gait efficiency were assessed for each crutch type at both S-SWVs. Subjects negotiated two architectural barriers (stairs and ramp) and completed a subjective questionnaire concerning crutch preferences. Walking with either crutch type resulted in slower S-SWVs, greater VO2, higher relative exercise intensity, and reduced gait efficiency compared with values for normal unassisted ambulation. An analysis of variance for these variables revealed nonsignificant between-crutch differences. Based on the subjective data, a preference for the standard single-tip crutch was evident. Within the scope of the study, the results supported no apparent advantage relative to energy expenditure to using the rocker-bottom crutch.

The purpose of this study was to determine the effect of conventional low-intensity transcutaneous electrical nerve stimulation (TENS) waveform and frequency characteristics on experimentally induced acute pain. Each of 28 male subjects received six forms of TENS and one control treatment during a single testing session. Treatments used one of two waveforms (monophasic or biphasic) and one of three frequencies (30, 60, or 85 Hz) administered to the forearm. Treatment effects were ascertained from alterations in pain-threshold and pain-tolerance responses induced by noxious electrical stimulation of the ipsilateral fifth digit. The TENS waveform and frequency had a negligible effect on pain threshold. The results indicated that waveform did not influence pain tolerance significantly. Pain tolerance, however, increased significantly at the frequency of 60 Hz but decreased significantly at both 30 and 85 Hz (p less than .05). We concluded that TENS frequency is an important factor in altering the subjects' perception of experimentally induced pain.

The purpose of this study was to test the significance of differences between cardiopulmonary responses to wall-pulley arm exercise and to bicycle ergometer leg exercise. The heart rate responses were greater for arm exercise than for leg exercise at comparable external work rates or energy cost levels. The systolic blood pressure responses and myocardial oxygen cost were greater for arm exercise at given external work loads, but not at comparable energy cost levels. The clinical and theoretical significance of these results is discussed.

This study examined the relationship between total energy cost and cardiac effort for a set of graded calisthenics that have been used in cardiac rehabilitation programs. Cardiac effort was quantified by calculating myocardial oxygen cost from the product of heart rate and systolic blood pressure. Total energy cost was determined by measuring oxygen uptake during steady-state exercise. Results indicate that total energy-cost values accurately reflect the cardiac effort required during the performance of these calisthenic exercises by normal subjects.

Physical therapists require an accurate, reliable method for measuring muscle strength. They often use manual muscle testing or hand-held dynametric muscle testing (DMT), but few studies document the reliability of MMT or compare the reliability of the two types of testing. We designed this study to determine the intrarater reliability of MMT and DMT. A physical therapist performed manual and dynametric strength tests of the same five muscle groups on 11 patients and then repeated the tests two days later. The correlation coefficients were high and significantly different from zero for four muscle groups tested dynametrically and for two muscle groups tested manually. The test-retest reliability coefficients for two muscle groups tested manually could not be calculated because the values between subjects were identical. We concluded that both MMT and DMT are reliable testing methods, given the conditions described in this study. Both testing methods have specific applications and limitations, which we discuss.

The purpose of this article is to provide background information concerning the cardiopulmonary responses to physical exercise. The focus is on acute and chronic responses to both strengthening and endurance exercise. Knowledge of normal exercise physiology provides the frame of reference for comparison with abnormal responses, especially as exercise relates to patients with cardiovascular disease.

The focus of this article is on the acute care and rehabilitation of the patient with coronary artery disease. The purpose is to provide an overview of the clinical treatment used at the University of Iowa Hospital, for the practicing physical therapist who may be unfamiliar with this type of patient. The three primary phases of the cardiac rehabilitation program are discussed with emphasis on the treatment of the patient with a post-myocardial infarction. Specific guidelines regarding evaluation and progression of physical activity are provided.