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A common treatment option for many breast and prostate cancer patients is the use of a luteinizing hormone-releasing hormone agonist such as goserelin acetate (GA) which reduces sex hormone levels. This treatment, however, is associated with bone degeneration, and exercise has been suggested as a means of preventing this side effect. Little is known about the effects of low intensity, low volume exercise on GA-induced bone loss. The purpose of this study, therefore, was to investigate the effects of voluntary wheel running on bone architecture in growing male (M) and female (F) rats receiving GA treatment. Rats received an 8-week GA treatment or placebo (CON) and were either housed in cages equipped with voluntary running wheels (WR) or remained sedentary (SED) in standard cages throughout the experimental period. Following treatments, tibiae were excised and analyzed for cortical bone (cross-sectional volume, cortical volume, marrow volume, cortical thickness) and cancellous bone (bone volume/total volume, trabecular number, trabecular thickness, trabecular spacing) using micro-computed tomography. Treatment with GA resulted in a significant reduction in running wheel distances in both sexes throughout the study period (P0.05). GA treatment had no effect on cortical bone architecture in neither sex (P0.05). Cancellous bone degeneration, however, was observed in M and F SED+GA (P0.05). No significant differences were observed in M WR+GA animals in bone volume/total volume, trabecular number and trabecular spacing when compared to M SED+CON (P0.05). In F WR+GA, trabecular thickness did not differ from that of F SED+CON (P0.05), and trabecular spacing was found to be significantly lower than F SED+GA (P0.05). The current report indicates that 8 weeks of GA treatment promotes cancellous bone degeneration, and voluntary wheel running provides no clear osteoprotection in growing male and female rats.

The purpose of this investigation was to determine the response of three parameters used in the assessment of acute myocardial infarction (AMI) after a single bout of eccentric exercise designed to elicit skeletal muscle injury. Total creatine kinase (CK), CK-MB isoenzyme (CK-MB), and the leukocyte differential were determined after a 20-minute bench-stepping exercise in 21 men ranging in age from 30 to 45 years. Comparison of several criteria showed that the use of CK-MB or the relative lymphocyte percentage alone resulted in 11% and 1.8%, respectively, of data collection points exceeding cutoff values suggestive of AMI. However, the use of both parameters in combination completely eliminated false-positive results with no data collection points meeting the criterion. It is thus suggested that CK-MB activity in conjunction with the relative lymphocyte percentage may not only provide incremental value in the detection of AMI but also reduce the incidence of misdiagnosis associated with exercise.

Summary Postural alignment is not an inherent trait. Proper alignment is acquiredthrough training postural muscle groups. This training is based on scientific principles associated with improving the physiological parameters of muscle mechanics. The purpose of this report is to describe and demonstrate the application of exercise physiology training principles to the improvement of postural alignment, which may enhance vocal performance. Specific exercise principles are explained and key concepts highlighted. Selected exercises for training postural muscles are presented to assist in establishing techniques that result in the expected adaptations. The application of training principles to postural muscles has been shown to improve postural alignment by strengthening synergistic muscles and establishing a balance between the agonistic and antagonistic activity of these muscles. Since posture has been well established as an important component of vocal performance, the application of these principles to vocal training seems to warrant the attention of vocal trainers and performers.

Creatine phosphokinase (CPK) and creatine kinase-MB (CK-MB) have been used extensively as diagnostic markers for myocardial infarction and skeletal muscle injury. Many factors affect the variability of serum CPK and serum CK-MB activity, especially physical activity. We discuss the influence of physical activity on muscle and serum CPK and CK-MB. The effect of acute and chronic exercise on CPK and CK-MB activity emphasizes the need to use measurements of serum CPK and CK-MB with caution when evaluating and diagnosing acute myocardial infarctions and skeletal muscle injury.