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Doxorubicin (DOX) is associated with cardiac dysfunction and irreversible testicular damage. Androgen deprivation therapy (ADT) is administered prior to DOX treatment to preserve testicular function. However, ADT may exacerbate DOX-induced cardiac dysfunction. Exercise is cardioprotective, but the effects of exercise on cardiac function during combined ADT and DOX treatment are currently unknown. In this study, male Sprague–Dawley rats were randomly assigned to experimental groups: control (CON), ADT, DOX, or ADT+DOX. Animals received ADT or control implants on days 1 and 29 of the 56-day protocol. Animals remained sedentary (SED) or engaged in treadmill endurance exercise (TM) beginning on day 1. On day 15, the animals received DOX at 1 mg·(kg body mass)–1·d–1 by intraperitoneal injection for 10 consecutive days, or an equivalent volume of saline. On day 57, cardiac function was assessed in vivo and ex vivo. Animals treated with DOX alone, or with combined ADT+DOX, showed significant (P < 0.05) reductions in left ventricular developed pressure (–21% and –27%), maximal rate of pressure development (–29% and –32%), and maximal rate of pressure decline (25% and 31%), respectively when compared with the sedentary control animals. Endurance exercise training attenuated (P > 0.05) cardiac dysfunction associated with combined ADT+DOX treatment, indicating that exercise during simultaneous ADT+DOX treatment is cardioprotective.

There is growing concern regarding the long-term negative side effects of chemotherapy in childhood cancer survivors. Doxorubicin (DOX) is commonly used in the treatment of childhood cancers and has been shown to be both cardiotoxic and osteotoxic. It is unclear whether exercise can attenuate the negative skeletal effects of this chemotherapy. Rat pups were treated with saline or DOX. Animals remained sedentary or voluntarily exercised. After 10 weeks, femoral bone mineral content and bone mineral density were measured using dual-energy x-ray absorptiometry. Cortical and cancellous bone architecture was then evaluated by microcomputed tomography. DOX had a profound negative effect on all measures of bone mass and cortical and cancellous bone architecture. Treatment with DOX resulted in shorter femora and lower femoral bone mineral content and bone mineral density, lower cross-sectional volume, cortical volume, marrow volume, cortical thickness, and principal (IMAX, IMIN) and polar (IPOLAR) moments of inertia in the femur diaphysis, and lower cancellous bone volume/tissue volume, trabecular number, and trabecular thickness in the distal femur metaphysis. Exercise failed to protect bones from the damaging effects of DOX. Other modalities may be necessary to mitigate the deleterious skeletal effects that occur in juveniles undergoing treatment with anthracyclines.

The use of exercise to minimize doxorubicin (DOX)-induced cardiotoxicity is gaining attention. However, very few clinically relevant reports exist investigating the effects of exercise performed during and following DOX treatments. The purpose of this study, therefore, was to examine the effects of voluntary wheel running during and following DOX treatment using two models of late-onset DOX cardiotoxicity in the rat. Female Sprague-Dawley rats received either DOX or saline injections using one of two separate treatment regimens. These regimens involved either daily or weekly DOX injections with cumulative doses for both protocols totaling 15 mg/kg. Daily DOX injections were 1 mg/kg and lasted for 15 consecutive days while weekly DOX injections were 2.5 mg/kg and lasted for six consecutive weeks with control animals receiving matched saline injection regimens. Immediately following the initial DOX/saline injection, animals were randomly housed in cages with voluntary running wheels or standard rat cages throughout DOX/saline treatments and continued until reaching 10 weeks. Cardiac function was then assessed using echocardiography and an isolated working heart model, and myosin heavy chain (MHC) isoform distribution was assessed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. When compared wth controls, daily DOX treatment resulted in reduced running wheel distances at weeks 2-10 (P < 0.05), and weekly DOX treatment resulted in reduced running wheel distances at weeks 2, 6 and 10 (P < 0.05). Nonetheless, wheel running during and following daily and weekly DOX dosing protected against DOX-induced cardiotoxicity by preserving maximal mitral and aortic blood flow velocities, left ventricular developed pressure and MHC isoform expression. In conclusion, the overall reduced volume of activity during and following daily and weekly DOX treatments attenuated DOX-induced cardiac dysfunction suggesting that low-volume endurance training may be an effective rehabilitative approach in minimizing DOX cardiotoxicity in cancer patients.

Background Childhood cancer survivors are at greater risk of cardiovascular complications once they reach adulthood. Anthracyclines may be a major contributor to these delayed-onset complications, yet their use continues because of favorable clinical outcomes. Exercise has been shown to protect against anthracycline cardiotoxicity, yet it is unclear whether exercise can protect against delayed-onset cardiotoxicity when treatment is initiated in childhood. The aim of the present study was to determine if exercise training provides cardioprotection in a juvenile rat model of delayed-onset anthracycline cardiotoxicity. Procedure At 25 days of age, male Sprague–Dawley rat pups were subjected to a treatment regimen with the anthracycline doxorubicin (DOX). Pups received DOX at 2 mg/kg on 7 consecutive days (cumulative dose 14 mg/kg) or saline as a control. At the time DOX treatment began, pups remained sedentary or were allowed to voluntarily exercise. Ten weeks after the initiation of exercise, cardiac function was assessed both in vivo and ex vivo. Results DOX treatment stunted normal growth and significantly impaired cardiac function. While voluntary exercise did not offset changes in the growth curve, it did provide significant cardioprotection against DOX-induced cardiotoxicity. Conclusions Exercise training, initiated at the time treatment begins, can protect against delayed-onset anthracycline-induced cardiotoxicity in adult rats that were treated with anthracyclines as juveniles. Pediatr Blood Cancer 2012; 59: 149–154. © 2011 Wiley Periodicals, Inc.

Acute doxorubicin (DOX) cardiotoxicity can be attenuated by exercise preconditioning, but little is known of whether this cardioprotection continues beyond 10 days post-DOX administration. The purpose of this study was to determine the effects of exercise preconditioning on early chronic DOX-induced cardiotoxicity. Male rats were randomly assigned to sedentary, treadmill, or wheel running groups. Treadmill and wheel running animals participated in a progressive treadmill training protocol or voluntary wheel running, respectively, for 10 weeks. Following the intervention, animals were further randomized to receive either DOX (sedentary + DOX, treadmill + DOX, wheel running + DOX) or saline (sedentary + saline, treadmill + saline, wheel running + saline). All animals then remained sedentary for 4 weeks. A 22% reduction in fractional shortening was observed in left ventricles from previously sedentary animals receiving DOX when compared with sedentary + saline. This degree of decline was not observed in treadmill + DOX and wheel running + DOX. Sedentary + DOX possessed significantly depressed mitral and aortic valve blood flow velocities when compared with sedentary + saline, but these decrements were not observed in treadmill + DOX and wheel running + DOX. Ex vivo analysis revealed that left ventricular developed pressure and maximal rate of pressure development were significantly lower in sedentary + DOX when compared to sedentary + saline. Treadmill and wheel running prior to DOX treatment protected against these decrements. Exercise cardioprotection was associated with preserved myosin heavy chain but not sarcoendoplasmic reticulum Ca2+ ATPase 2a expression. In conclusion, 10 weeks of prior exercise protected against early chronic DOX cardiotoxicity suggesting that training status may be a determining factor in the degree of late-onset cardiotoxicity experienced by cancer patients undergoing treatment with DOX.

Early detection and improved treatments for cancer have resulted in roughly 12 million survivors alive in the United States today. This growing population faces unique challenges from their disease and treatments, including risk for recurrent cancer, other chronic diseases, and persistent adverse effects on physical functioning and quality of life. Historically, clinicians advised cancer patients to rest and to avoid activity; however, emerging research on exercise has challenged this recommendation. To this end, a roundtable was convened by American College of Sports Medicine to distill the literature on the safety and efficacy of exercise training during and after adjuvant cancer therapy and to provide guidelines. The roundtable concluded that exercise training is safe during and after cancer treatments and results in improvements in physical functioning, quality of life, and cancer-related fatigue in several cancer survivor groups. Implications for disease outcomes and survival are still unknown. Nevertheless, the benefits to physical functioning and quality of life are sufficient for the recommendation that cancer survivors follow the 2008 Physical Activity Guidelines for Americans, with specific exercise programming adaptations based on disease and treatment-related adverse effects. The advice to "avoid inactivity," even in cancer patients with existing disease or undergoing difficult treatments, is likely helpful. 4.106 JCR (2010) Q1, 3/80 Sport sciences UEM

Breast cancer is the most prevalent type of cancer in American women. Exercise appears to diminish many of the side effects resulting from breast cancer and its treatment. Very little research, however, has compared the outcomes of varying lengths of combined aerobic and resistance training exercise interventions on physiological and psychological parameters in breast cancer survivors. The purpose of this study was to compare the physiological and psychological outcomes following 3 and 6 months of exercise in breast cancer survivors. Breast cancer survivors (N = 114) participated in either 3 months of prescriptive, individualized exercise (3M; n = 29), 6 months of prescriptive, individualized exercise (6M; n = 68), or served as sedentary controls (C; n = 17). Cancer survivors completed a medical evaluation and assessment at baseline followed by a predetermined 3- or 6-month exercise intervention. Cancer survivors in the control group performed no exercise between the initial assessment and 6-month reassessment. Cardiovascular endurance, pulmonary function, muscular endurance, fatigue, and symptoms of depression were assessed at baseline and post intervention. Repeated measures ANCOVA revealed improvements (P < 0.05) in cardiovascular endurance, fatigue, and symptoms of depression in breast cancer survivors undergoing 3- and 6-month individualized exercise interventions. Breast cancer survivors exercising for 6 months showed additional improvements (P < 0.05) in pulmonary function and muscular endurance. Cancer survivors in the control group did not improve in cardiovascular endurance, pulmonary function, muscular endurance, or fatigue. Three months of individualized, prescriptive exercise leads to improved cardiovascular endurance, fatigue, and symptoms of depression in breast cancer survivors. Additional benefits are seen if exercise is continued for a total of 6 months.

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.

To investigate the effects of supervised exercise training on cardiopulmonary function and fatigue in cancer survivors undergoing various clinical treatments.Pretest and post-test quasiexperimental.Outpatient oncology rehabilitation center.96 breast cancer survivors undergoing various clinical treatments.Subjects were divided into four groups based on the specific type of clinical treatment: surgery alone (n = 22); surgery and chemotherapy (n = 30); surgery and radiation (n = 17); and surgery, chemotherapy, and radiation (n = 27). Following a comprehensive screening and medical examination, cardiovascular endurance, pulmonary function, and fatigue were assessed, leading to the development of an individualized exercise prescription and a six-month exercise intervention. Repeated-measures analysis of variance and covariance were used to compare the effectiveness of the intervention and differences among treatment groups.Systolic and diastolic blood pressure, resting heart rate, forced vital capacity, forced expiratory volume, predicted oxygen consumption, time on treadmill, and fatigue.Cardiopulmonary function (predicted maximal oxygen consumption and time on treadmill) significantly increased in all groups after exercise training. In addition, resting heart rate and forced vital capacity significantly improved in those receiving surgery, chemotherapy, and radiation. Psychologically, the exercise intervention resulted in significant reductions in behavioral, affective, sensory, cognitive and mood, and total fatigue scale scores in all three groups who received treatment with surgery. The breast cancer survivors in the surgery-alone group showed significant reductions in behavioral, affective, and total fatigue scale scores but not in sensory and cognitive and mood fatigue scale scores.The results suggest that moderate intensity, individualized, prescriptive exercise maintains or improves cardiopulmonary function with concomitant reductions in fatigue regardless of treatment type. Moreover, cancer survivors receiving combination chemotherapy and radiotherapy following surgery appear to benefit to a greater extent as a result of an individualized exercise intervention.Clinicians need to be aware of adjuvant therapies such as moderate exercise that attenuate negative side effects of cancer treatments. Symptom management recommendations should be given to cancer survivors concerning the effectiveness of exercise throughout the cancer continuum and the importance of participating in a cancer rehabilitation exercise program.

Numerous methods have been used to minimize the cardiotoxic effects of the chemotherapeutic agent doxorubicin (DOX), and most have had limited success. Chronic endurance exercise has been shown to protect against DOX cardiotoxicity, but little is known regarding the effects of acute exercise on DOX-induced cardiac dysfunction. Purpose. The purpose of this study was to determine the effects of a single bout of acute endurance exercise on the cardiac dysfunction associated with DOX treatment. Methods. Male Sprague-Dawley rats either performed an acute exercise bout on a motorized treadmill for 60 minutes at a maximal speed of 25 m/min with a 5% grade (EX) or remained sedentary (SED) 24 hours before receiving either a 15-mg/kg DOX bolus dose or saline (SAL). Cardiac function was then analyzed 5 days post injection using a Langendorff isolated perfused heart model. In addition, myocardial lipid peroxidation was analyzed as an indicator of oxidative stress. Results. Doxorubicin treatment alone (SED+DOX) promoted a significant decline in end-systolic pressure (—35%), left ventricular developed pressure (—59%), and the maximal rate of left ventricular pressure development (—43%) as well as a 45% increase in lipid peroxidation products when compared with SED+SAL ( P < .05). Acute exercise 24 hours before DOX treatment, however, had a cardioprotective effect, as end-systolic pressure, left ventricular developed pressure, and the maximal rate of left ventricular pressure development were significantly higher in EX+DOX compared with SED+DOX ( P < .05) and EX+DOX had similar levels of lipid peroxidation products as SED+SAL Conclusions. An acute exercise bout performed 24 hours before DOX treatment protected against cardiac dysfunction, and this exercise-induced cardioprotection may partly be explained by a reduction in the generation of reactive oxygen species.

This investigation determined the cardiopulmonary function and fatigue alterations in male cancer survivors during treatment as well as following treatment utilizing similar exercise assessment protocols and individualized, prescriptive exercise interventions. The study included 45 male cancer survivors that were referred by local oncologists. Following a comprehensive screening and physical examination, cardiovascular endurance, pulmonary function, and fatigue were assessed leading to the development of 12-week individualized exercise prescriptions and exercise interventions. The cancer survivors were divided into during treatment (DTm) and following treatment (FTm) groups. Repeated-measures analysis of variance and analyses of covariance were used to compare pre- versus postintervention and between groups. Cardiopulmonary function was maintained in the DTm, whereas the FTm showed significant reductions in resting heart rate ( P < .05) with concurrent increases in predicted VO2max and time on treadmill ( P < .05) postexercise intervention. Fatigue levels did not increase in the DTm group, whereas the FTm group showed significant reductions in behavioral fatigue, affective fatigue, sensory fatigue, cognitive/mood fatigue, and total fatigue ( P < .05) after the exercise intervention. The results of the current study suggest that moderate intensity, individualized, prescriptive exercise intervention maintains or improves cardiovascular and pulmonary function with concomitant reductions in fatigue in cancer survivors during and following cancer treatment. Exercise appears to be a safe, efficacious strategy for improving physical fitness in cancer survivors during and following treatment.

BACKGROUND. Cancer treatments have serious physiological and psychological side effects in cancer survivors. This investigation examined cardiopulmonary function and fatigue in breast cancer survivors during and after treatment by using similar exercise assessments, prescriptions, individualized interventions, and reassessments. METHODS. The study included 113 women diagnosed with breast cancer. Participants were grouped according to whether they participated in an individualized prescriptive exercise program during cancer treatment (DTm) or after cancer treatment (FTm). After a comprehensive screening and medical examination, cardiovascular endurance, pulmonary function, and fatigue were assessed, which led to the development of an individualized 6-month exercise prescription and exercise intervention. Repeated-measures analysis of variance (ANOVA) and analyses of covariance (ANCOVA) were used to compare the effectiveness of the intervention and differences between groups. RESULTS. Cardiopulmonary function (systolic blood pressure, time on treadmill) improved in the DTm group (P < .05), whereas the FTm group showed reductions in systolic and diastolic blood pressure and resting heart rate (P < .05) with concurrent increases in percentage of predicted FVC, % of predicted FEV1, predicted VO2max, and time on treadmill (P < .05). Psychologically, the DTm group showed reductions in behavioral, sensory, and total fatigue (P < .05), whereas the FTm group showed reductions in behavioral, affective, sensory, cognitive/mood, and total fatigue (P < .05). CONCLUSIONS. The current study suggested that moderate intensity, individualized, prescriptive exercise maintains or improves cardiovascular and pulmonary function with concomitant reductions in fatigue during and after cancer treatment. However, it is critical that exercise be individualized to specific needs of the cancer survivor to prevent exacerbation of cancer treatment toxicities. Cancer 2007; 110:918–25. © 2007 American Cancer Society.

Purpose: This study examined the effects of an 8-week androgen deprivation therapy treatment using Zoladex and an endurance training regimen on cardiac function. Methods: Male Sprague–Dawley rats received either Zoladex or placebo. Animals remained sedentary or endurance trained during the drug treatment period. On day 57, ex vivo cardiac function was analyzed. Results: Hearts from sedentary animals receiving Zoladex possessed significant cardiac dysfunction. However, hearts from exercise trained rats receiving Zoladex possessed cardiac function values similar to those from hearts from placebo animals. Conclusions: An 8-week treatment with Zoladex promoted cardiac dysfunction. Endurance training during Zoladex treatment protected against this cardiac dysfunction.

The use of doxorubicin, a highly effective antitumor antibiotic, is limited by a dose-dependent cardiotoxicity. The purpose of this study was to determine whether chronic exercise training (ET) prior to doxorubicin treatment would preserve cardiac function and reduce myocardial oxidative stress following treatment. Rats were exercise trained on a motorized treadmill or confined to sedentary cage activity for 12 weeks, then administered an intraperitoneal injection of doxorubicin (15 mg/kg) or 0.9% saline. Five days following the injections, hearts were isolated and Langendorf perfused to assess cardiac function and then processed for biochemical analyses. Doxorubicin treatment induced significant inotropic, lusitropic, and chronotropic cardiac dysfunction, reduced coronary flow, and increased cardiac lipid peroxidation in the sedentary animals. Doxorubicin treatment was also associated with a decrease in cardiac manganese superoxide dismutase protein expression and an increase in heat shock protein-72 (Hsp72) compared with saline-treated animals. Exercise training attenuated doxorubicin-induced cardiac dysfunction, and lipid peroxidation, and led to a greater cardiac expression of Hsp72 compared with the sedentary animals. The results of this study demonstrate for the first time that chronic exercise training before doxorubicin treatment protects against cardiac dysfunction following treatment, and provide evidence for a sustained increase in myocardial Hsp72 following exercise training and doxorubicin treatment in vivo.

The clinical use of doxorubicin (DOX) is limited by a dose-dependent cardiotoxicity. The purpose of this study was to determine whether voluntary exercise training would confer protection against DOX cardiotoxicity in the isolated perfused rat heart. Female Sprague-Dawley rats were randomly assigned to standard holding cages or cages with running wheels for 8 wk. Twenty-four hours after the sedentary (SED) or voluntary exercise (VEX) running period, rats were anesthetized with pentobarbital sodium, and hearts were isolated and perfused with oxygenated Krebs-Henseleit (KH) buffer at a constant flow of 15 ml/min. After a 20-min stabilization period, hearts were paced at 300 beats per minute and perfused with KH buffer containing 10 μM DOX for 60 min. A set of control hearts from SED and VEX rats were perfused under identical conditions without DOX for the same period. DOX perfusion led to significant decreases in left ventricular developed pressure, +dP/d t, and −dP/d t, and significant increases in LV lipid peroxidation in sedentary rats compared with non-DOX controls ( P < 0.05). Prior voluntary exercise training attenuated these DOX-induced effects and was associated with a significant increase (78%, P < 0.05) in heat shock protein (HSP72), but not mitochondrial isoform of SOD (MnSOD) or CuZnSOD protein expression in the hearts of wheel-run animals. These data indicate that chronic physical activity may provide resistance against the cardiac dysfunction and oxidative damage associated with DOX exposure and provide novel evidence of HSP72 induction in the heart after voluntary exercise.

Purpose. Despite mounting evidence indicating that exercise training has a positive effect on cancer recovery, the influence of cancer type on the response to exercise training remains uncharacterized. Therefore, the adaptations to exercise training were compared between groups composed of 7 different forms of cancer. Methods. A total of 319 cancer survivors completed fatigue inventories and participated in assessments of cardiorespiratory function, which encompassed aerobic capacity (VO2peak), pulmonary function (forced vital capacity [FVC] and forced expiratory volume in 1 second [FEV1]), and resting blood pressure and heart rate. Participants were divided into 7 groups based on cancer type, including breast cancer (BC, n = 170), prostate cancer and other male urogenital neoplasia (PC, n = 38), hematological malignancies (HM, n = 34), colorectal cancer (CC, n = 25), gynecological cancers (GC, n = 20), glandular and epithelial neoplasms (GEN, n = 20), and lung cancer (LC, n = 12). All participants completed an individualized, multimodal exercise intervention consisting of cardiorespiratory, flexibility, balance, and muscular strength training 3 days per week for 3 months. Following the intervention, all subjects were reassessed. Generalized Estimating Equations with exchangeable working correlation structure was used to model each response; the group by time interaction effect represented the effect of cancer type on exercise-associated improvements. Results. No significant ( P > .05) group by time interaction effects were observed between different types of cancer for any parameter. Pre- to postexercise contrasts revealed significant improvements in VO2peak in BC, PC, HM, and GEN at the Bonferroni adjusted significance level (.00714). Heart rate was significantly lowered in the BC and CC groups. Mean fatigue indices decreased by at least 17% in all groups, but these changes were only significant in the BC, HM, CC, and GC groups. Systolic blood pressure decreased significantly in BC and GC, and diastolic blood pressure decreased significantly only in the BC group while pulmonary function remained unchanged in all cancer types. Conclusion. Although trends toward improved cardiorespiratory and fatigue parameters only reached significance in some groups, there were no significant differences between cancer types. This suggests that cardiorespiratory and fatigue improvements following rehabilitative exercise are not dependent on cancer type. Further research investigating alternative physiological parameters are needed to confirm the relationship between cancer type and exercise-mediated rehabilitation.

Despite evidence that cancer and its treatments severely reduce cardiorespiratory fitness (CRF), normative data for cancer survivors do not exist. The present study identifies age and gender-specific CRF distributions in a cancer population. The use of cancer-specific normative CRF data may help stratify initial fitness status and assess improvements in response to exercise interventions in cancer survivors. Data from 703 cancer survivors were analyzed for this study. Quintiles were compiled for peak oxygen consumption (VO 2 peak), forced vital capacity (FVC), and forced expiratory volume (FEV 1 ) for males and females in 5 age groups (19–39, 40–49, 50–59, 60–69, and ≥70 years of age). VO 2 peak values for the cancer population were significantly lower than the general US population. The cancer population average in each age group fell within the “very poor” classification of VO 2 peak values for the general population. FVC values in the cancer population were similar to the general population. Cancer survivors had very low age group-specific VO 2 peak values compared to the apparently healthy general US population. Previously, CRF values of cancer survivors were compared to normative values for the apparently healthy general population, which yielded imprecise classifications of initial fitness and changes in fitness, resulting in patient discouragement.

The objective was to determine whether serum creatine kinase (CK) and serum CK MB activity following exercise-induced muscle damage activity differs among females of varying menarchial status and to determine whether there is a relationship between serum estradiol (E2) concentration, CK, and CK MB activity. Fifteen menarchial (M), 15 premenarchial (P), and 10 postmenopausal (PM) females participated in the study. Exercise consisted of eccentric hamstring contractions. Estradiol concentrations were significantly higher in M women (p = .0001; M, 125.0 ± 20.8 pg/mL, P, 54.6 ± 38.6 pg/mL, PM, 46.2 ± 34.6 pg/mL). Menarchial women had lower resting CK and CK MB activity and responded with a higher efflux of CK and CK MB post exercise (p = .0001). An inverse relationship was found between E2 concentration and baseline CK (p = .02) and CK MB activity (p = .006). No relationship existed between post exercise efflux of CK and CK MB and E2 concentration. At rest, E2 influenced CK and CK MB activity across menarchial levels. However, E2 did not significantly reduce the level of CK and CK MB activity following this intense bout of eccentric exercise. Key words: exercise-induced muscle damage, estradiol, menarhial, premenarchial, postmenopausal

PURPOSE The objective of this investigation was to determine the effects of varying levels of dietary protein on the postexercise increase in serum and muscle enzyme activity normally observed following exercise-induced muscle injury. METHODS Serum creatine kinase (CK), serum aspartate aminotransferase (AST), and muscle glucose-6-phosphate dehydrogenase (G-6-PD) activities were measured in rats fed for 10 d on high (50%), normal (12%), or low (4%) protein diets following a single bout of eccentric exercise (treadmill running at 16 m.min(-1), -16 degrees incline, 90 min). RESULTS The exercise intervention resulted in significant increases in serum CK and AST activities in all diet groups. Serum CK demonstrated peak activity immediately postexercise with increases reaching 910+/-94, 594+/-53, and 283+/-52 IU.L(-1) for animals on high, normal, and low protein diets, respectively. Similarly, peak postexercise AST activity for high, normal, and low protein diets reached 193+/-10, 147+/-3, and 162+/-9 IU.L(-1), respectively. The exercise intervention resulted in increases in muscle G-6-PD activity for all diet groups; however, LP rats demonstrated significantly lower values than NP or HP rats. CONCLUSIONS These data show that dietary protein intake can significantly effect both serum and muscle enzyme activity following acute exercise-induced muscle injury.

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.

Estrogen ingestion has been suggested as a protective mechanism of muscle membrane integrity against an exercise‐induced muscle inflammatory response. Serum creatine kinase (CK) concentration and the heart muscle isoenzyme CK‐MB have been used as diagnostic markers of muscle disruption following exercise. The purpose of this study was to determine the difference in serum CK, CK‐MB, and perceived soreness following exercise‐induced muscle disruption in females taking an oral contraceptive (OC) and those not. Subjects included sixteen females, eight in the experimental group and eight in the control group. Estrogen concentration, determined pre‐exercise, was 181 ± 45 pg/ml for the OC group and 124 ± 25 pg/ml for the controls, respectively. Subjects participated in an eccentric hamstring exercise which consisted of six sets of ten repetitions at 110% of concentric 1RM. Serum CK, CK‐MB concentration and perceived soreness were assessed pre‐exercise and immediately, 24,48,72 and 96 hours post‐exercise. Serum C...

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.

Doxorubicin (DOX) is an effective antineoplastic agent with well-characterized cardiotoxic effects. Although exercise has been shown to protect against DOX cardiotoxicity, a clear and concise mechanism to explain its cardioprotective effects is lacking. The purpose of this study was to determine if exercise training reduces cardiac DOX accumulation, thereby providing a possible mechanism to explain the cardioprotective effects of exercise against DOX toxicity.Sprague-Dawley rats were randomly assigned to 1 of 3 primary experimental groups: sedentary (n = 77), wheel running (n = 65), or treadmill (n = 65). Animals in wheel running and treadmill groups completed 10 weeks of exercise before DOX treatment. DOX was administered 24 hours after the last training session as a bolus intraperitoneal injection at 10 mg/kg. Subgroups of rats from each primary group were killed at 1, 3, 5, 7, and 9 days after DOX exposure to assess cardiac function and DOX accumulation.Ten weeks of exercise preconditioning reduced myocardial DOX accumulation, and this reduction in accumulation was associated with preserved cardiac function.These data suggest that the cardioprotective effects of exercise against DOX-induced injury may be due, in part, to a reduction in myocardial DOX accumulation.

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.

A high-fat diet has been shown to exacerbate the cardiotoxicity associated with the chemotherapy drug doxorubicin (DOX); however, it is unknown whether switching from a high-fat diet to a low-fat diet can attenuate the intensified DOX cardiotoxicity. The purpose of this study was to investigate the effects of a low-fat diet on DOX-induced cardiotoxicity in rats previously fed a high-fat diet.Male rats were randomly assigned to consume a Western diet or a low-fat diet for 6 weeks. Western diet-fed rats were then further randomized to switch to the low-fat diet (WD-LF) or continue with the Western diet (WD). One week later, WD-LF and WD received 1 mg/kg DOX per day for 10 consecutive days and continued with their diets (WD-LF + DOX, WD + DOX). LF was further randomized to receive 1 mg/kg DOX per day for 10 consecutive days (LF + DOX) or saline injections as a control (LF + SAL). Four weeks following the first injection, cardiac function was analyzed, and left ventricles were analyzed for cardiotoxicity indices.When compared to LF + SAL and LF + DOX, WD + DOX exhibited an enhanced cardiotoxicity as evidenced by reduced septal wall thickness, fractional shortening, and sarco-endoplasmic reticulum Ca(2+) ATPase expression as well as increased left ventricular cavity dimensions, lipid peroxidation, and β-myosin heavy-chain expression. This exacerbated cardiotoxicity was not observed in WD-LF + DOX.Switching to a low-fat diet 1 week prior to, during, and following DOX treatment attenuated the exacerbated cardiotoxicity observed in the previously Western diet-fed rats.

Doxorubicin (DOX)-induced muscle dysfunction may contribute to patient fatigue, but the nature of this myotoxicity remains unclear. The purpose of this study was to characterize the muscle function dose-response to DOX. A secondary purpose was to compare the degree of DOX-induced muscle dysfunction to the observed cardiac dysfunction.Rats received DOX at 10 mg/kg (DOX1), 12.5 mg/kg (DOX2), or 15 mg/kg (DOX3). Muscle and cardiac function were assessed 5 days, post injection.Compared to controls, DOX2 and DOX3 soleus and DOX3 extensor digitorum longus (EDL) had lower maximal twitch force (p0.05). Soleus fatigue rate was altered by DOX, but EDL fatigue rate was not. Additionally, fractional shortening was lower in DOX2 and DOX3 compared to controls (p0.05).DOX impaired muscle function in a dose-dependent manner. The degree of dysfunction was greater in the soleus and was consistent with the observed cardiac dysfunction.

Childhood cancer survivors are at greater risk of cardiovascular complications once they reach adulthood. Anthracyclines may be a major contributor to these delayed-onset complications, yet their use continues because of favorable clinical outcomes. Exercise has been shown to protect against anthracycline cardiotoxicity, yet it is unclear whether exercise can protect against delayed-onset cardiotoxicity when treatment is initiated in childhood. The aim of the present study was to determine if exercise training provides cardioprotection in a juvenile rat model of delayed-onset anthracycline cardiotoxicity.At 25 days of age, male Sprague-Dawley rat pups were subjected to a treatment regimen with the anthracycline doxorubicin (DOX). Pups received DOX at 2 mg/kg on 7 consecutive days (cumulative dose 14 mg/kg) or saline as a control. At the time DOX treatment began, pups remained sedentary or were allowed to voluntarily exercise. Ten weeks after the initiation of exercise, cardiac function was assessed both in vivo and ex vivo.DOX treatment stunted normal growth and significantly impaired cardiac function. While voluntary exercise did not offset changes in the growth curve, it did provide significant cardioprotection against DOX-induced cardiotoxicity.Exercise training, initiated at the time treatment begins, can protect against delayed-onset anthracycline-induced cardiotoxicity in adult rats that were treated with anthracyclines as juveniles.

Doxorubicin (DOX) and goserelin acetate (GA), when administered individually, can lead to impaired cardiac function via different mechanisms. Combining GA and DOX (GA + DOX), however, could potentially exacerbate cardiac dysfunction when compared to GA and DOX treatments administered individually. Therefore, the first purpose of this study was to investigate the effects of GA + DOX on cardiac function. Additionally, since exercise training has been shown to protect against GA- and DOX-induced cardiac dysfunction when administered individually, the second purpose of this study was to examine the effects of exercise during GA + DOX on cardiac function. Female rats were randomly assigned to control (CON), GA, DOX, GA + DOX, or exercise training during GA + DOX (EX GA + DOX). Following 56 days, cardiac function was analyzed in vivo using echocardiography and ex vivo using an isolated working heart model. GA + DOX had significantly lower mitral valve maximal and mean blood flow velocities and aortic valve maximal blood flow velocity than CON (in vivo analysis, P

This study investigated exercise‐induced muscle enzyme release in master runners by assessing the activity of total serum creatine kinase (total CK) and the concentration of the isoenzyme creatine kinase MB (CK‐MB). Subjects were 12 male (54 ± 9 years) and seven female (50 ± 6 years) master marathon runners. Premarathon (24 hours before) and postmarathon serum samples were collected (24, 48, 72, and 96 hours after the race). Total CK was measured enzymatically and CK‐MB concentration was assayed utilizing a double antibody procedure. The men's and women's 24 hour (1012 U/L, 782 U/L) and 48 hour (581 U/L, 441 U/L) postrace mean total CK activities were significantly (p≤0.05) elevated above prerace values (66 U/L, 119 U/L). CK‐MB concentration 24 hours postrace was also significantly (≤0.05) elevated from prerace values (0.27 ng/ml, 0.0 ng/ml) in both males (34.4 ng/ml) and females (16.7 ng/ml). The results of this study indicate that the pattern of exercise‐induced muscle enzyme release from the stress of ...

Interest in the potential benefits of exercise and fitness programs has led many corporations to invest in such for their employees. Fitness program directors need to better understand factors that affect employees' decisions to participate. The purpose of this study was to examine whether male and female participants and nonparticipants differed in their conceptual and institutional motives for involvement in a corporate exercise program. The Exercise Program Survey was developed and administered randomly to 310 employees of a metropolitan insurance company. Participants scored items associated with enhancing fitness, reducing stress and learning to relax as more important than nonparticipants did. Participants also indicated that the institutional motive structure was more important, thus emphasizing the need for appropriate times, places, and availability of instruction. Women felt more strongly than men that weight control, fitness, stress reduction, relaxation, and smoking cessation activities were necessary components of a fitness program. Women also scored the structure and health institutional motives as more important.

The clinical use of the highly effective chemotherapeutic agent doxorubicin (DOX) is limited by its dose-dependent cardiotoxicity. This cardiotoxicity is associated with a cardiac myosin heavy chain (MHC) isoform shift from the alpha isoform to the beta isoform. Exercise prior to DOX treatment has been shown to attenuate the MHC shift associated with DOX, but little is known about the cardioprotective nature of exercise during DOX treatment.DOX-treated rats were assigned to normal cage activity (sedentary, SED+DOX) or 24-hour voluntary wheel running access (WR+DOX). All animals received weekly 2.5 mg/kg DOX injections for 6 weeks (15 mg/kg cumulative) and hearts were subsequently excised for determination of MHC isoform expression using sodium dodecyl sulfate polyacrylamide gel electrophoresis.At baseline, WR+DOX rats on average ran 62+/-4 km, and at week 6 ran 30+/-5 km, which was significantly lower than baseline (p0.05). SED+DOX hearts expressed 57+/-7% of MHC as the alpha-MHC isoform and 43+/-7% as the beta-MHC isoform. WR+DOX hearts expressed 76+/-4% as the alpha-MHC and 24+/-4% as the beta-MHC isoform, which was significantly different from that of SED+DOX (p0.05).DOX treatment significantly reduced wheel running activity, but this reduced running distance deemed to be cardioprotective as hearts from WR+DOX rats contained significantly greater levels of the favorable alpha-MHC isoform than SED+DOX.

This study investigated the differences and relationships between body fat and plasma lipoproteins using the noninvasive and validated measurements of fat‐free mass by total body electrical conductivity (TOBEC). Total body water, lean body mass, and total body fat were measured by TOBEC along with determinations of plasma lipoproteins [total cholesterol (TC), low density lipoprotein, high density lipoprotein (HDL‐C), and triglyceride] in 40 college‐aged male and female swimming and track athletes. Body weight (mean ± SD, 69.9 ± 0.6 vs. 60.0 ± 3.8 kg), total body water (42.4 ± 0.5 vs. 32.4 ± 0.5 liters), and fat‐free mass (57.9 ± 0.7 vs. 44.3 ± 0.7 kg) were significantly higher in the males compared with the females. Total body fat (15.5 ± 3.4 vs. 12.3 ± 0.4 kg) and percent fat (23.3 ± 6.1 vs. 19.7 ± 2.9) were higher in the swimming athletes than in the track athletes. The female swimmers had significantly higher percent body fat (29.3 ± 2.4 vs. 22.5 ± 3.9) than the female track athletes. Plasma HDL‐C was ...

To determine if endurance exercise training performed prior to administration of the anticancer drugs DOX and GW2974 would be cardioprotective.Rats remained sedentary or exercise trained for 10 weeks. Following the exercise or sedentary period, rats were randomly assigned to treatment groups. Rats in sedentary and exercise groups received saline or a combination of 10 mg/kg DOX and 30 mg/kg GW2974. Cardiac function was assessed 2, 5, or 10 days following treatments.Sedentary animals receiving DOX/GW2974 experienced significant cardiac dysfunction. At 2-, 5-, and 10-days post, cardiac function in trained, drug-treated animals was significantly preserved. Additionally, animals exercised prior to DOX/GW2974 injections had significantly lower levels of myocardial lipid peroxidation and caspase-3 and -8 activities compared to their sedentary counterparts.Exercise training protected against the cardiac dysfunction associated with DOX/GW2974 administration and may be related to an inhibition in apoptotic signaling.

The clinical use of the chemotherapeutic drug doxorubicin (DOX) is limited due to a dose-dependent cardiotoxicity. Evidence is mounting that exercise protects against DOX-related cardiac dysfunction, and as such, it may be possible that prior endurance training promotes defense against DOX cardiotoxicity. Purpose: To examine the effects of exercise preconditioning on acute DOX-induced cardiotoxicity, and to determine whether any observed cardioprotection was associated with myosin heavy chain (MHC) isoform alterations. Methods: Male Sprague-Dawley rats trained on a motorized treadmill, had access to voluntary running wheels, or remained sedentary for 10 wk prior to being injected with either saline or 10 mg[middle dot]kg-1 DOX. Left ventricular function was then assessed in vivo using transthoracic echocardiography and ex vivo using the isolated working heart at 5 and 10 d after injection. Additionally, left ventricular MHC isoform expression was analyzed as a possible mechanism to explain exercise-induced cardioprotection. Results: DOX treatment promoted significant in vivo and ex vivo cardiac dysfunction at 5 and 10 d after injection in sedentary animals, and this dysfunction was associated with an upregulation of the [beta]-MHC isoform. Exercise preconditioning protected against DOX-induced cardiac dysfunction at 5 and 10 d after injection by attenuating [beta]-MHC upregulation. Conclusion: Endurance training prior to DOX treatment protects against acute DOX cardiotoxicity for up to 10 d, and this protection can potentially be explained by a preservation of MHC isoform distribution.

Reducing testosterone and estrogen levels with a luteinizing hormone-releasing hormone agonist such as Zoladex (i.e., chemical gonadectomy) is a common treatment for many prostate and breast cancer patients, respectively. There are reports of surgical gonadectomy inducing cardiac dysfunction, and exercise has been shown to be cardioprotective under these circumstances. Minimal research has been done investigating the effects of chemical gonadectomy and increased physical activity on cardiac function. The purpose of this investigation was to examine the effects of chemical gonadectomy and physical activity on cardiac function. Male (M) and female (F) Sprague-Dawley rats received either Zoladex treatment (Zol) that suppressed gonadal function for 8 wk or control implants (Con) and either were allowed unlimited access to voluntary running wheels (WR) or remained sedentary (Sed) throughout the treatment period. In vivo and ex vivo left ventricle (LV) function were then assessed, and myosin heavy chain (MHC) expression was analyzed to help explain LV functional differences. Hearts from M Sed+Zol exhibited significantly lower aortic blood flow velocity, developed pressure, and maximal rate of pressure development and higher β-MHC expression than M Sed+Con. Hearts from F Sed+Zol exhibited significantly lower LV wall thicknesses, fractional shortening, and developed pressure and higher β-MHC expression than F Sed+Con. This cardiac dysfunction was not evident in hearts from M or F WR+Zol, and this was associated with a preservation of the MHC isoform distribution. Thus an 8-wk chemical gonadectomy with Zoladex promoted cardiac dysfunction in male and female rats, and voluntary wheel running protected against this cardiac dysfunction.

Background Cancer survivors experience muscular weakness and reduced mobility, thereby compromising quality of life. This investigation utilized moderate prescriptive exercise to improve upper- and lower-body muscular fitness, flexibility, depression and quality of life in cancer patients. Patients and methods One hundred and thirty-five breast and prostate cancer survivors received cancer and medical history screening and a medical examination, as well as assessments of muscular strength (handgrip dynamometer) and endurance (bench press, lateral pull-down, leg press, shoulder press and curl-up crunch test), flexibility (Modified Sit and Reach), depression (Beck Depression Inventory) and quality of life (Quality of Life Index). Following the exercise assessments, cancer survivors trained in resistance exercise for 6 months during treatment or following treatment based on their results from the assessments and health status. Results Cancer survivors following treatment showed significant (P = 0.006) improvements in upper-body muscular endurance (+46.8%), lower-body muscular endurance (+67.1%), core muscular endurance (+32.5%) and flexibility (+6.2%), with concomitant improvements (P = 0.013) in depression (–25.6%) and total quality of life (+7.2%). Cancer survivors during treatment showed significant (P = 0.012) improvements in upper-body muscular endurance (+79.1%) and lower-body muscular endurance (+49.7%) while maintaining core endurance and flexibility in conjunction with improvements (P = 0.022) in depression (–43.0%) and quality of life (+11.5%). Conclusions Moderate-intensity individualized prescriptive exercise is a safe and efficacious means to augment muscular function and improve the quality of life of cancer survivors.

Breast cancer treatment often results in impaired shoulder function, in particular, decrements in muscular endurance and range of motion, which may lead to decreased quality of life. The purpose of this investigation was to determine the effects of walking pole use on shoulder function in female breast cancer survivors. Participants had previously been treated with 1 or a combination of the following: mastectomy, breast conservation therapy, axillary lymph node dissection, chemotherapy, or radiation. Participants were randomly placed in experimental (n = 6) and control (n = 6) groups and met with a cancer exercise specialist 2 times each week for 8 weeks. The experimental group used walking poles during the 20-minute aerobic portion of their workout, whereas the control group did not use walking poles but performed 20 minutes of aerobic exercise per workout session. Both groups participated in similar resistance training programs. Testing was done pre- and postexercise intervention to determine upper body muscular endurance and active range of motion at the glenohumeral joint. Repeated-measures analysis of variance (ANOVA) revealed significant improvements in muscular endurance as measured by the bench press ( P = .046) and lat pull down ( P = .013) in the walking pole group. No within-group improvements were found in the group that did not use walking poles. The data suggest that using a walking pole exercise routine for 8 weeks significantly improved muscular endurance of the upper body, which would clearly be beneficial in helping breast cancer survivors perform activities of daily living and regain an independent lifestyle.

Doxorubicin (Dox) is a highly effective antineoplastic antibiotic associated with a dose-limiting cardiotoxicity that may result in irreversible cardiomyopathy and heart failure. The purpose of this study was to examine the effects of low-intensity exercise training (LIET) during the course of Dox treatment on cardiac function, myosin heavy chain expression, oxidative stress, and apoptosis activation following treatment. Male Sprague-Dawley rats either remained sedentary or were exercise trained on a motorized treadmill at 15 m/min, 20 min/day, 5 days/wk (Monday through Friday) for 2 wk. During the same 2-wk period, Dox (2.5 mg/kg) or saline was administered intraperitoneally to sedentary and exercised rats 3 days/wk (Monday, Wednesday, Friday) 1–2 h following the exercise training sessions (cumulative Dox dose: 15 mg/kg). Five days following the final injections, hearts were isolated for determination of left ventricular (LV) function, lipid peroxidation, antioxidant enzyme protein expression, 72-kDa heat shock protein expression, caspase-3 activity, and myosin heavy chain isoform expression. Dox treatment significantly impaired LV function and increased caspase-3 activity in sedentary animals ( P < 0.05). LIET attenuated the LV dysfunction and apoptotic signal activation induced by Dox treatment and increased glutathione peroxidase expression, but it had no significant effect on lipid peroxidation, protein expression of myosin heavy chain isoforms, 72-kDa heat shock protein, or superoxide dismutase isoforms. In conclusion, our data suggest that LIET applied during chronic Dox treatment protects against cardiac dysfunction following treatment, possibly by enhancing antioxidant defenses and inhibiting apoptosis.

Objectives: Estrogen is metabolized in the body through two mutually exclusive pathways yielding metabolites with different biological activities: the low estrogenic 2-hydroxyestrone (2-OHE1) and the highly estrogenic 16α-hydroxyestrone (16α-OHE1). The ratio of these metabolites (2/16) may be predictive of risk for developing breast cancer. Early evidence has demonstrated that exercise may alter estrogen metabolism to favor the weak estrogen, 2-OHE1. Methods : Seventy-seven eumenorrheic females completed physical activity logs for two weeks prior to providing a luteal phase urine sample. Concentrations of 2-OHE1 and 16α -OHE1 were measured and the 2/16 ratio computed. Hierarchical regression, controlling for age and body mass index (BMI), was used to determine relationships between estrogen metabolites and daily physical activity. Results : Regression analyses indicated significant positive relationships between physical activity and 2-OHE1 and the 2/16 ratio (p < 0.05) that appears to be independent of BMI. 16αOHE1 was not significantly related to physical activity. Conclusion : These results indicate that physical activity may modulate estrogen metabolism to favor the weak estrogen, 2-OHE1, thus producing a higher 2/16 ratio. This alteration in estrogen metabolism may represent one of the mechanisms by which increased physical activity reduces breast cancer risk.

Purpose: Although evidence is accumulating that suggests regular moderate physical activity improves physiological and psychological well-being of cancer patients undergoing chemotherapy, the mechanisms involved remain unclear. Therefore, the purpose of this study was to determine if exercise training improves endothelium-dependent vasodilation after exposure to the chemotherapeutic agent 5-fluorouracil (5-FU). Methods: Rats were injected with N-methyl-N-nitrosourea (MNU) and assigned to either exercise (EX; treadmill running, 20-25 m.min -1 , 15% grade, 30 min.d -1 , 5 d.wk -1 for 8 wk) or sedentary (SED) groups. After the exercise training period, aortic rings were obtained and used to assess contractile and relaxation characteristics. In addition, endothelial nitric oxide synthase (eNOS) protein content and eNOS enzyme activity was determined. Results: Exercise training resulted in increased maximal endothelium-dependent vasorelaxation to acetylcholine (ACh, I × 10 -5 M) (SED, 56 ± 3%; exercise, 71 ± 5%; P < 0.05) after norepinephrine-induced (1 X 10 -7 M) vasoconstriction. Exposure of aortic rings from each group to increasing concentrations of 5-FU (7 X 10 -5 -7 × 10 -3 M) resulted in vasoconstriction. Rings obtained from exercise-trained animals demonstrated enhanced vasorelaxation to ACh (1 X 10 -5 M) after 5-FU-induced vasoconstriction compared with rings obtained from SED animals (P < 0.05). In addition, exercise training enhanced eNOS protein content and eNOS activity. Conclusion: Exercise training enhances endothelium-dependent vasorelaxation after 5-FU-induced vasoconstriction, and this may be due, at least in part, to an increase in aortic eNOS protein content and activity. Such exercise-induced adaptations may help alleviate chemotherapy-related fatigue observed in cancer patients.

This study was conducted to determine if an initial bout of resistance (weight lifting) exercise by untrained women results in any alterations in indicators of acute myocardial infarction (AMI). Untrained women performed 4 resistance exercises at 70% of their 1 repetition maximum. Blood samples were obtained during the 12 h post-exercise and analyzed for total creatine kinase (CK)-MB, CK-MB subforms 1 and 2, and the relative lymphocyte percentage. Exercise resulted in significant increases in total CK-MB, CK-MB(1), CK-MB(2), and the CK-MB(2)/CK-MB(1) ratio, total leukocyte count, and lymphocyte count. Using several criteria for the assessment of AMI, 22-25% of subjects completing the protocol demonstrated increases in CK-MB(2), CK-MB(2)/CK-MB(1) ratio, and relative lymphocyte percentages that were suggestive of AMI. Thus, our data suggest that moderate resistance exercise can significantly alter blood indicators of AMI, emphasizing the need to determine recent exercise history in patients with possible AMI.

Exercise for cancer patients is gaining support. In the current case study, a female breast cancer patient was diagnosed with breast cancer at the age of 29 years; she underwent a left modified radical mastectomy. She developed cancer again in the opposite breast at the age of 57 years and had a right modified radical mastectomy. After the second mastectomy (the right breast), the patient received chemotherapy and radiation. Following her cancer treatments, she participated in an exercise intervention for 6 months at the University of Northern Colorado's Rocky Mountain Cancer Rehabilitation Institute. A 6-month reassessment showed that she increased her muscular strength and cardiovascular function in addition to attenuating her cancer-related fatigue and depression. It is recommended that health professionals work together to ensure that a collaborative effort is undertaken to increase functional work capacity that will significantly improve patients' quality of life.