Systolic blood pressure responses during isometric contractions of large and small muscle groups.

The purpose of this study was to test for a difference between the systolic blood pressure responses to voluntary contractions of large and small muscle groups of the upper extremity. Systolic blood pressure was measured at approximately 20 sec intervals during sustained isometric contractions of the index finger adductors and handgrip muscles contracting at 40% of maximal voluntary contraction (MVC). Contractions were terminated when EMG activity exceeded 10% of maximal activity of selected accessory muscles or when the 40% MVC tension could no longer be held constant (+/-10%). The slopes of the regression lines representing systolic blood pressure responses to sustained isometric contraction of a small and large muscle group of the upper extremity were significantly different (p less than .001). Older theories that pressor responses are determined only by the % MVC and not by the mass of contracting muscle need to be reexamined.

Assessing exercise tolerance: a review.

The purpose of this article is to provide guidelines for monitoring and assessing exercise tolerance. Monitoring and interpreting pulse rate, blood pressure, respiration, skin characteristics, fatigue, pain, coordination, and electrocardiography are discussed. The basis for applying these principles to graded-exercise-tolerance testing is also discussed.

Establishing activity and training levels for patients with ischemic heart disease.

The paper presents guidelines for determining ideal training heart rates and recreational and occupational energy-cost levels for individual patients with ischemic heart disease. These guidelines were established by Karvonen, are based on results of progressive exercise testing, and have been applied to a broad spectrum of subjects in outpatient conditioning programs. How to apply these guidelines to establish beneficial and safe activity levels is illustrated with a fictional patient's medical history, progressive exercise test results, and recreational and occupational history and preferences.

Exercise response during wall-pulley versus bicycle ergometer work.

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 a comparable energy cost levels. The clinical and theoretical significance of these results is discussed.

Energy cost of rehabilitation calisthenics.

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.

Comparison of the effectiveness of two pelvic stabilization systems on pelvic movement during maximal isometric trunk extension and flexion muscle contractions.

The purpose of this study was to compare the effectiveness of two pelvic fixation systems to limit pelvic movement during isometric trunk extension and flexion muscle strength testing. We developed a prototypal pelvic fixation system and compared it with a pelvic strap stabilization system. The prototypal pelvic fixation system consisted of fixation of the anterior superior iliac spines and sacrum, and the pelvic strap stabilization system consisted of a strap across the anterior superior iliac spines and a posterior pad. Small, but statistically significant, pelvic position changes occurred during isometric trunk extension and flexion muscle strength testing with the two stabilization systems. The pelvic angle changes were greater in extension than in flexion and greater when only the pelvic strap stabilization system rather than the prototypal pelvic fixation system was used. Our findings indicate that a more extensive prototypal pelvic fixation system minimizes pelvic movement to a greater extent during isometric trunk extension and flexion muscle contractions compared with the strap stabilization system.

Evaluation of a group exercise program for elderly women.

The purpose of this study was to evaluate the physical training effect of a specific set of calisthenics performed by a supervised group of elderly women. The exercise program was designed to be performed by groups of subjects without using expensive equipment, large gymnasiums, or outdoor facilities. Fourteen women with an average age of 75.7 years trained for eight weeks. Five women with an average age of 71.8 years served as the control group. Submaximal graded exercise tolerance (GXT) step tests were performed before and after training. Significant decreases in submaximal GXT heart rate (HR), systolic blood pressure (SBP), and rate-pressure product (RPP) were observed in the exercise group. Predicted maximal aerobic power (MAP) increased 12.4% in the exercise group. The control group demonstrated significant decreases for submaximal GXT SBP and RPP, but not for HR. Predicted MAP for the control group decreased 3.3%. We concluded that this particular training regimen could be used safely and effectively with elderly subjects. The decrease in submaximal GXT HR, SBP, and RPP and the increase in predicted MAP indicate that a training effect can be expected when this exercise regimen is performed by sedentary elderly women.

Clinical determination of energy cost and walking velocity via stopwatch or speedometer cane and conversion graphs.

Work rate and relative exercise intensity are basic considerations in developing optimal exercise training prescriptions in cardiopulmonary rehabilitation. Velocity and energy cost of walking are directly related to work rate and indirectly related to exercise intensity. This article describes two methods of measuring walking velocity and estimating oxygen uptake. The validity and accuracy of the methods are discussed. We believe both methods are clinically useful. Because one method uses a specially instrumented speedometer cane, technical information concerning its design and construction is also included.

Effects of pelvic and lower extremity stabilization on isometric trunk extension and flexion muscle strength*.

The purpose of this study was to evaluate the effect of varying the type of pelvic and lower extremity stabilization on isometric trunk extension and flexion muscle strength measurements. Two pelvic stabilization systems, one consisting of fixation of the anterior superior iliac spines and sacrum (pelvic fixation) and the second, a strap across the anterior superior iliac spines and a posterior pad at the sacrum (pelvic strap) were compared. The lower extremities were or were not strapped at the thigh, calf, and feet. Torque values for the pelvic fixation system were not different from the pelvic strap system with lower extremity stabilization. Torque values were less with no lower extremity stabilization with both pelvic stabilization systems for flexion but not for extension muscle contractions. The use of an extensive pelvic stabilization system did not produce greater isometric force output than the use of a simple pelvic strap. The use of lower extremity stabilization did produce greater isometric flexion force output than the use of no lower extremity stabilization. J Ortho Sports Phys Ther 1987;9(3):111-117.

Muscle strength at the trunk*.

The purpose of this study was to determine the strength of trunk flexors and extensors in normal male subjects during isometric, concentric, and eccentric contractions. Subjects were tested in the sidelying position to minimize the effects of gravity. The pelvis and lower extremities were measured on a custom built force table (lowa Force Table). Muscle strength was expressed as a moment of force (external force times the moment arm) in Newton-meter (Nm) units. Greater Nm were registered in the muscle-lengthened position than in the muscle-shortened position for all isometric contractions. The Nm registered for eccentric contractions always exceeded the Nm registered for concentric contractions of the same muscle group. The Nm registered during contractions of trunk extensors always exceeded the values obtained during corresponding modes of contractions (isometric, eccentric, and concentric) of trunk flexors.J Orthop Sports Phys Ther 1980;1(3):165-170.

Infarct size and exercise capacity after myocardial infarction.

Estimation of infarct size from serum creatine phosphokinase elevations of 22 acute myocardial infarction (AMI) patients was compared to their functional exercise capacity determined on a bicyle ergometer. Eleven of these patients entered a controlled exercise program for 3-4 mo and were subsequently retested. Aerobic power of the exercise group increased significantly (mean +- SE 1.42 +- 0.5 met) and was also significantly greater than an unpaired control group tested the same number of months after infarct. Patients grouped 2.5-4.5 mo post-AMI demonstrated a correlation between aerobic power and estimated infarct size (r = -0.68, n = 15). This correlation was higher (r = -0.84, n = 11) after 3-4 mo of a controlled exercise program.