Exercise training and losartan improve endothelial function in heart failure rats by different mechanisms

Objectives. To investigate the mechanisms of losartan- and exercise training-induced improvements on endothelial dysfunction in heart failure. Design. Sprague-Dawley rats subjected to left coronary artery ligation inducing myocardial infarction and heart failure were randomized to losartan treatment, high-intensity exercise training, or both. Results. Losartan, but not exercise training, reduced the heart failure-associated elevation in left ventricular end-diastolic pressure (26 ± 2 mmHg vs. 19 ± 1 mmHg after losartan). In contrast, both exercise training and losartan improved exercise capacity, by 40% and 20%, respectively; no additional effects were observed when exercise training and losartan were combined. Aortic segments were mounted on a force transducer to determine vasorelaxation. Heart failure impaired endothelium-dependent vasorelaxation, observed as a 1.9-fold reduced response to acetylcholine (EC50). Exercise and losartan improved acetylcholine-mediated vasorelaxation to the same extent, but by different mechanisms. Exercise training upregulated the nitric oxide pathway, whereas losartan upregulated a non-nitric oxide or -prostacyclin pathway; possibly involving the endothelium-dependent hyperpolarizing factor. Conclusions. Both losartan and exercise training reversed endothelial dysfunction in heart failure; exercise training via nitric oxide-dependent vasorelaxation, and losartan via an unknown mechanism that may involve endothelium-dependent hyperpolarizing factor. Thus, the combined treatment activated an additional nitric oxide- independent mechanism that contributed to reduce endothelial dysfunction

Mechanisms of exercise-induced improvements in the contractile apparatus of the mammalian myocardium

One of the main outcomes of aerobic endurance exercise training is the improved maximal oxygen uptake, and this is pivotal to the improved work capacity that follows the exercise training. Improved maximal oxygen uptake in turn is at least partly achieved because exercise training increases the ability of the myocardium to produce a greater cardiac output. In healthy subjects, this has been demonstrated repeatedly over many decades. It has recently emerged that this scenario may also be true under conditions of an initial myocardial dysfunction. For instance, myocardial improvements may still be observed after exercise training in post-myocardial infarction heart failure. In both health and disease, it is the changes that occur in the individual cardiomyocytes with respect to their ability to contract that by and large drive the exercise training-induced adaptation to the heart. Here, we review the evidence and the mechanisms by which exercise training induces beneficial changes in the mammalian myocardium, as obtained by means of experimental and clinical studies, and argue that these changes ultimately alter the function of the whole heart and contribute to the changes in whole-body function

Impact of exercise-nutritional state interactions in patients with type 2 diabetes

Introduction This study examines the role of nutritional status during exercise training in patients with type 2 diabetes mellitus by investigating the effect of endurance-type exercise training in the fasted versus the fed state on clinical outcome measures, glycemic control, and skeletal muscle characteristics in male type 2 diabetes patients. Methods Twenty-five male patients (glycated hemoglobin (HbA1c), 57 ± 3 mmol·mol−1 (7.4% ± 0.3%)) participated in a randomized 12-wk supervised endurance-type exercise intervention, with exercise being performed in an overnight-fasted state (n = 13) or after consuming breakfast (n = 12). Patients were evaluated for glycemic control, blood lipid profiles, body composition and physical fitness, and skeletal muscle gene expression. Results Exercise training was well tolerated without any incident of hypoglycemia. Exercise training significantly decreased whole-body fat mass (−1.6 kg) and increased high-density lipoprotein concentrations (+2 mg·dL−1), physical fitness (+1.7 mL·min−1·kg−1), and fat oxidation during exercise in both groups (PTIME 0.05). HbA1c concentrations significantly decreased after exercise training (PTIME < 0.001), with a significant greater reduction after consuming breakfast (−0.30% ± 0.06%) compared with fasted state (−0.08% ± 0.06%; mean difference, 0.21%; PTIME × GROUP = 0.016). No interaction effects were observed for skeletal muscle genes related to lipid metabolism or oxidative capacity. Conclusions Endurance-type exercise training in the fasted or fed state do not differ in their efficacy to reduce fat mass, increase fat oxidation capacity, and increase cardiorespiratory fitness and high-density lipoprotein concentrations or their risk of hypoglycemia in male patients with type 2 diabetes. HbA1c seems to be improved more with exercise performed in the postprandial compared with the postabsorptive state

Strength Training Prior to Endurance Exercise: Impact on the Neuromuscular System, Endurance Performance and Cardiorespiratory Responses

This study aimed to investigate the acute effects of two strength-training protocols on the neuromuscular and cardiorespiratory responses during endurance exercise. Thirteen young males (23.2 ± 1.6 years old) participated in this study. The hypertrophic strength-training protocol was composed of 6 sets of 8 squats at 75% of maximal dynamic strength. The plyometric strength-training protocol was composed of 6 sets of 8 jumps performed with the body weight as the workload. Endurance exercise was performed on a cycle ergometer at a power corresponding to the second ventilatory threshold until exhaustion. Before and after each protocol, a maximal voluntary contraction was performed, and the rate of force development and electromyographic parameters were assessed. After the hypertrophic strength-training and plyometric strength-training protocol, significant decreases were observed in the maximal voluntary contraction and rate of force development, whereas no changes were observed in the electromyographic parameters. Oxygen uptake and a heart rate during endurance exercise were not significantly different among the protocols. However, the time-to-exhaustion was significantly higher during endurance exercise alone than when performed after hypertrophic strength-training or plyometric strength-training (p <0.05). These results suggest that endurance performance may be impaired when preceded by strength-training, with no oxygen uptake or heart rate changes during the exercise

Exercise Preferences Among Young Adults: Do Men and Women Want Different Things?

Background Young adult men are difficult to recruit and retain in lifestyle interventions. This may be in part to gender differences in exercise goals observed in men, but little is known about exercise preferences for young adults, specifically. The purpose of this study is to compare the exercise preferences of young men and women to inform future interventions in this area. We hypothesize that men will prefer strength training at higher rates than women, and that women will prefer supervised guidance at higher rates than men. Methods The sample included 288 young adults aged 18-25 (mean age=21.85, SD=2.2). Majority were women and within a normal BMI range (M=25.91, SD=5.3). An anonymous online survey study was completed. Participants were asked their preferred type of exercise (moderate intensity cardio, strength training, intense strength training, or a combination of cardio and strength training), and if they preferred to exercise at a clinic-based facility with supervised guidance or to exercise alone with guidance.Chi-square tests were conducted to determine if there are gender differences in preferences for exercise type and mode of delivery, accounting for BMI. Results Over two-third of young adults preferred a combination of moderate intensity cardio and strength training. Women and men differed significantly in their exercise preferences (p=\u3c .001). Less than 1% of women preferred intense strength training compared to the 15.3% of men. Women (17.4%) preferred moderate intensity cardio at higher rates than men (12.2%). However, when examining outcomes by BMI category, these results were only significantly different among individuals within a normal BMI (p=.000). Majority of young adults (67.7%) prefer exercising with their own with guidance from a program. Men and women did not differ in their preference to exercise with guidance or in a clinic-based program with supervision (p=.115). Conclusion Findings suggest that young adults overall prefer a combination of strength training and cardio, conducted on their own with guidance from a program. However, young men were more likely to prefer intense strength training; this was particularly true among men in a normal BMI range. These findings may be used to inform the tailoring of recruitment messaging and lifestyle interventions targeting this high-risk population.https://scholarscompass.vcu.edu/gradposters/1033/thumbnail.jp

Improvement of heart rate recovery after exercise training in older people.

Twenty-four subjects aged 70 and older were retrospectively selected from our archives and screened for symptoms of cardiovascular disease. Baseline exercise test was negative for myocardial ischemia in all subjects. All subjects had completed an 8-week program, performed for a variety of indications and consisting of an aerobic physical training program including 30 minutes of cycling three times per week at 65% to 75% of maximum heart rate achieved at peak exercise test performed at enrollment, an educational intervention, dietary advice, and psychological support. All subjects underwent a cardiopulmonary exercise test (CPX) before and at the end of exercise training. At the end of each CPX, peak oxygen uptake (VO2peak), the rate of increase of ventilation per unit of increase of carbon dioxide production (VE/VCO2slope), and HRR were recorded. Twenty-five healthy subjects younger than 60 with no evidence of exercise-induced myocardial ischemia and not enrolled in any exercise training program were also retrospectively selected from our archives and used as a control group for analyzing HRR. These patients performed two exercise tests several weeks apart. Several studies have shown that changes in vagal tone can be used as an outcome tool that helps identify patients or subjects with or without cardiovascular disease at risk for a cardiovascular event, although the evidence of a prognostic value of HRR in older subjects without cardiovascular disease is rather poor. In this study, exercise training resulted in HRR improvement in healthy elderly subjects, suggesting that exercise training improves vagal/sympathetic balance in older subjects without cardiovascular disease as well. Whether the observed improvement in HRR may have long-term beneficial prognostic effects was not the aim of the study, although a beneficial effect might be postulated, in light of the Framingham dat

espida Training Exercise

This learning document is intended to accompany the espida Handbook and offer training in how to use the Handbook. The espida Approach is an aid in articulating the value of projects where the primary outcomes are intangible and thus in the creation of business cases and demonstrating the return on those investments

The effects of pre-exhaustion, exercise order, and rest intervals in a full-body resistance training intervention

Pre-exhaustion (PreEx) training is advocated on the principle that immediately preceding a compound exercise with an isolation exercise can target stronger muscles to pre-exhaust them to obtain greater adaptations in strength and size. However, research considering PreEx training method is limited. The present study looked to examine the effects of a PreEx training programme. Thirty-nine trained participants (male = 9, female = 30) completed 12 weeks of resistance training in 1 of 3 groups: a group that performed PreEx training (n = 14), a group that performed the same exercise order with a rest interval between exercises (n = 17), and a control group (n = 8) that performed the same exercises in a different order (compound exercises prior to isolation). No significant between-group effects were found for strength in chest press, leg press, or pull-down exercises, or for body composition changes. Magnitude of change was examined for outcomes also using effect size (ES). ESs for strength changes were considered large for each group for every exercise (ranging 1.15 to 1.62). In conclusion, PreEx training offers no greater benefit to performing the same exercises with rest between them compared with exercises performed in an order that prioritises compound movements

Survivors Speak: A Qualitative Analysis of Motivational Factors Influencing Breast Cancer Survivors’ Participation in a Sprint Distance Triathlon

Aims and Objectives To examine motivational factors influencing breast cancer survivors to participate in triathlon training, complete a triathlon and maintain an exercise thereafter. Background Routine exercise has been shown to improve quality of life and reduce recurrence for breast cancer survivors. Yet physical and psychological factors present barriers for initiating and maintaining an exercise routine. Research is limited in exploring factors of exercise motivation from the survivor\u27s perspective. Design Qualitative design using focus groups and individual follow-up phone interviews to explore motivation for exercise initiation and maintenance. Methods One to two weeks after completing a triathlon, 11 breast cancer survivors who trained together participated in one of three focus groups to discuss their experience. Five months post triathlon 6 of the 11 participants were successfully contacted and phone interviews were conducted to explore exercise maintenance. Focus groups and interviews were analysed using content and thematic analysis. Results Five themes emerged (1) Champion for Exercise, (2) Part of a Team, (3) Everyone Had a Story, (4) Not Really Exercise and (5) What Do We Do Now? Overall, survivors recognised their need for lifestyle change (e.g. moving from a sedentary lifestyle to a more active one). More importantly, they identified the team approach to exercise initiation was crucial in their success in sustaining a behavioural change. Conclusions Emphasis needed on developing team exercise training programmes for survivors. Nurses can play a critical role in discussing with survivors, the benefits of exercise initiation and maintenance. Relevance to clinical practice Breast cancer survivors are hesitant to initiate routine exercise. Training with women who share a common lived experience increases the likelihood of success. Nurses are in a position to encourage breast cancer survivors to participate in group exercise programmes as a way to improve quality of life

Promoting Team-Based Exercise Among African American Breast Cancer Survivors

Physical activity benefits the health and well-being of breast cancer survivors (BCS). Yet, many African American survivors do not routinely exercise and have increased risk of poor outcomes. The purpose of this mixed-method study was to identify motivational factors compelling African American BCS to participate in a 14-week team walking program and to intend to continue exercise after the intervention concluded. Focus groups were held with participants (n = 12) before and after training. Content analysis discovered themes before the intervention: Not wanting to go at it alone, exercise not a life or treatment priority, cancer treatment affected activity, advocates to exercise, and can exercise really help? Four themes postintervention themes included: In the same boat, changed mind-set, improved weight and activity, and overcoming barriers. Physical data verified improvements. Results suggest that a team-based exercise training program may assist in overcoming a sedentary behavior tendency and subsequently improve health among survivors