Is the Clinical Delivery of Cardiac Rehabilitation in an Australian Setting Associated with Changes in Physical Capacity and Cardiovascular Risk and Are Any Changes Maintained for 12 Months?

Long-term maintenance of changes in cardiovascular risk factors and physical capacity once patients leave the supervised program environment have not previously been reported. This study investigated the changes in physical capacity outcomes and cardiovascular risk factors in an Australian cardiac rehabilitation setting, and the maintenance of changes in these outcomes in the 12 months following cardiac rehabilitation attendance. Improvements in mean (95% CI) cardiorespiratory fitness (16.4% (13.2-19.6%), p < 0.001) and handgrip strength (8.0% (5.4-10.6%), p < 0.001) were observed over the course of the cardiac rehabilitation program, and these improvements were maintained in the 12 months following completion. Waist circumference (p = 0.003) and high-density lipoprotein cholesterol (p < 0.001) were the only traditional cardiovascular risk factors to improve during the cardiac rehabilitation program. Vigorous-intensity aerobic exercise was associated with significantly greater improvements in cardiorespiratory fitness, Framingham risk score, and waist circumference in comparison to moderate-intensity exercise. An increase in the intensity of the exercise prescribed during cardiac rehabilitation in Australia is recommended to induce larger improvements in physical capacity outcomes and cardiovascular risk. A standardized exercise test at the beginning of the rehabilitation program is recommended to facilitate appropriate prescription of exercise intensity.

Evaluating Exercise Progression in an Australian Cardiac Rehabilitation Program: Should Cardiac Intervention, Age, or Physical Capacity Be Considered?

Progression of prescribed exercise is important to facilitate attainment of optimal physical capacity during cardiac rehabilitation. However, it is not clear how often exercise is progressed or to what extent. This study evaluated whether exercise progression during clinical cardiac rehabilitation was different between cardiovascular treatment, age, or initial physical capacity. The prescribed exercise of sixty patients who completed 12 sessions of outpatient cardiac rehabilitation at a major Australian metropolitan hospital was evaluated. The prescribed aerobic exercise dose was progressed using intensity rather than duration, while repetitions and weight lifted were utilised to progress resistance training dose. Cardiovascular treatment or age did not influence exercise progression, while initial physical capacity and strength did. Aerobic exercise intensity relative to initial physical capacity was progressed from the first session to the last session for those with high (from mean (95%CI) 44.6% (42.2-47.0) to 68.3% (63.5-73.1); p < 0.001) and moderate physical capacity at admission (from 53.0% (50.7-55.3) to 76.3% (71.2-81.4); p < 0.001), but not in those with low physical capacity (from 67.3% (63.7-70.9) to 85.0% (73.7-96.2); p = 0.336). The initial prescription for those with low physical capacity was proportionately higher than for those with high capacity (p < 0.001). Exercise testing should be recommended in guidelines to facilitate appropriate exercise prescription and progression.

Ghrelin as a Biomarker of Stress: A Systematic Review and Meta-Analysis.

INTRODUCTION: Ghrelin is an orexigenic hormone which favors food-seeking behavior and has been postulated to be a biomarker of stress. We conducted a systematic review and meta-analysis on the evolution of ghrelin levels following acute stress. METHODS: The PubMed, Cochrane Library, Embase, and ScienceDirect databases were searched for studies reporting ghrelin levels before and after acute stress in humans. RESULTS: We included ten studies for a total of 348 patients. Acute stress (intervention) was always in a laboratory. Acute stress was psychological (Trier Social Stress Test), physical, or mixed (cold pressure test). The overall meta-analysis demonstrated an increase in ghrelin after the stress intervention (ES = 0.21, 95CI 0.09 to 0.34) compared with baseline levels. Stratification by time demonstrated an acute increase in ghrelin levels in the five minutes immediately following the initiation of stress (0.29, 0.10 to 0.48) but without any difference after. Obese individuals had a more significant (ES = 0.51, 95CI 0.18 to 0.84) and prolonged increase in ghrelin levels for up to 45 min compared with non-obese individuals who had a significant increase only five minutes after stress. Moreover, the ghrelin levels increased in response to stress with BMI (coefficient 0.028, 0.01 to 0.49; p = 0.013) and decreased with the time after the stress intervention (coefficient -0.007, -0.014 to -0.001; p = 0.025). CONCLUSION: Ghrelin is a biomarker of stress, with a short-term increase following acute stress. Obese individuals have both a higher and prolonged response, emphasizing the link between obesity and stress.

Coronavirus (COVID-19), Coagulation, and Exercise: Interactions That May Influence Health Outcomes.

The proinflammatory cytokine storm associated with coronavirus disease 2019 (COVID-19) negatively affects the hematological system, leading to coagulation activation and endothelial dysfunction and thereby increasing the risk of venous and arterial thrombosis. Coagulopathy has been reported as associated with mortality in people with COVID-19 and is partially reflected by enhanced D-dimer levels. Poor vascular health, which is associated with the cardiometabolic health conditions frequently reported in people with severer forms of COVID-19, might exacerbate the risk of coagulopathy and mortality. Sedentary lifestyles might also contribute to the development of coagulopathy, and physical activity participation has been inherently lowered due to at-home regulations established to slow the spread of this highly infectious disease. It is possible that COVID-19, coagulation, and reduced physical activity may contribute to generate a "perfect storm," where each fuels the other and potentially increases mortality risk. Several pharmaceutical agents are being explored to treat COVID-19, but potential negative consequences are associated with their use. Exercise is known to mitigate many of the identified side effects from the pharmaceutical agents being trialled but has not yet been considered as part of management for COVID-19. From the limited available evidence in people with cardiometabolic health conditions, low- to moderate-intensity exercise might have the potential to positively influence biochemical markers of coagulopathy, whereas high-intensity exercise is likely to increase thrombotic risk. Therefore, low- to moderate-intensity exercise could be an adjuvant therapy for people with mild-to-moderate COVID-19 and reduce the risk of developing severe symptoms of illness that are associated with enhanced mortality.

Acute cardiovascular responses to interval exercise: A systematic review and meta-analysis.

Interval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI -32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI -2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10-15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations.

Is Exercise Prescription in Cardiac Rehabilitation Influenced by Physical Capacity or Cardiac Intervention?

This study investigated the influence of cardiac intervention and physical capacity of individuals attending an Australian outpatient cardiac rehabilitation program on the initial exercise prescription. A total of 85 patients commencing outpatient cardiac rehabilitation at a major metropolitan hospital had their physical capacity assessed by an incremental shuttle walk test, and the initial aerobic exercise intensity and resistance training load prescribed were recorded. Physical capacity was lower in surgical patients than nonsurgical patients. While physical capacity was higher in younger compared with older surgical patients, there was no difference between younger and older nonsurgical patients. The initial exercise intensity did not differ between surgical and nonsurgical patients. This study highlights the importance of preprogram exercise testing to enable exercise prescription to be individualized according to actual physical capacity, rather than symptoms, comorbidities and age, in order to maximize the benefit of cardiac rehabilitation.

Cardiovascular risk of adipokines: a review.

Over the last two decades, the understanding of adipose tissue has undergone radical change. The perception has evolved from an inert energy storage tissue to that of an active endocrine organ. Adipose tissue releases a cluster of active molecules named adipokines. The severity of obesity-related diseases does not necessarily correlate with the extent of body fat accumulation but is closely related to body fat distribution, particularly to visceral localization. There is a distinction between the metabolic function of central obesity (visceral abdominal) and peripheral obesity (subcutaneous) in the production of adipokines. Visceral fat accumulation, linked with levels of some adipokines, induces chronic inflammation and metabolic disorders, including glucose intolerance, hyperlipidaemia, and arterial hypertension. Together, these conditions contribute to a diagnosis of metabolic syndrome, directly associated with the onset of cardiovascular disease. If it is well known that adipokines contribute to the inflammatory profile and appetite regulation, this review is novel in synthesising the current state of knowledge of the role of visceral adipose tissue and its secretion of adipokines in cardiovascular risk.

A review of guidelines for cardiac rehabilitation exercise programmes: Is there an international consensus?

BACKGROUND: Cardiac rehabilitation is an important component in the continuum of care for individuals with cardiovascular disease, providing a multidisciplinary education and exercise programme to improve morbidity and mortality risk. Internationally, cardiac rehabilitation programmes are implemented through various models. This review compared cardiac rehabilitation guidelines in order to identify any differences and/or consensus in exercise testing, prescription and monitoring. METHODS: Guidelines, position statements and policy documents for cardiac rehabilitation, available internationally in the English language, were identified through a search of electronic databases and government and cardiology society websites. Information about programme delivery, exercise testing, prescription and monitoring were extracted and compared. RESULTS: Leading cardiac rehabilitation societies in North America and Europe recommend that patients progress from moderate- to vigorous-intensity aerobic endurance exercise over the course of the programme, with resistance training included as an important adjunct, for maintaining independence and quality of life. North American and European guidelines also recommend electrocardiograph-monitored exercise stress tests. Guidelines for South America and individual European nations typically include similar recommendations; however, those in the United Kingdom, Australia and New Zealand specify lower-intensity exercise and less technical assessment of functional capacity. CONCLUSION: Higher-intensity aerobic training programmes, supplemented by resistance training, have been recommended and deemed safe for cardiac rehabilitation patients by many authorities. Based on research evidence, this may also provide superior outcomes for patients and should therefore be considered when developing an international consensus for exercise prescription in cardiac rehabilitation.

Physical activity intensity can be accurately monitored by smartphone global positioning system 'app'.

Monitoring physical activity is important to better individualise health and fitness benefits. This study assessed the concurrent validity of a smartphone global positioning system (GPS) 'app' and a sport-specific GPS device with a similar sampling rate, to measure physical activity components of speed and distance, compared to a higher sampling sport-specific GPS device. Thirty-eight (21 female, 17 male) participants, mean age of 24.68, s = 6.46 years, completed two 2.400 km trials around an all-weather athletics track wearing GPSports Pro™ (PRO), GPSports WiSpi™ (WISPI) and an iPhone™ with a Motion X GPS™ 'app' (MOTIONX). Statistical agreement, assessed using t-tests and Bland-Altman plots, indicated an (mean; 95% LOA) underestimation of 2% for average speed (0.126 km·h(-1); -0.389 to 0.642; p < .001), 1.7% for maximal speed (0.442 km·h(-1); -2.676 to 3.561; p = .018) and 1.9% for distance (0.045 km; -0.140 to 0.232; p < .001) by MOTIONX compared to that measured by PRO. In contrast, compared to PRO, WISPI overestimated average speed (0.232 km·h(-1); -0.376 to 0.088; p < .001) and distance (0.083 km; -0.129 to -0.038; p < .001) by 3.5% whilst underestimating maximal speed by 2.5% (0.474 km·h(-1); -1.152 to 2.099; p < .001). Despite the statistically significant difference, the MOTIONX measures intensity of physical activity, with a similar error as WISPI, to an acceptable level for population-based monitoring in unimpeded open-air environments. This presents a low-cost, minimal burden opportunity to remotely monitor physical activity participation to improve the prescription of exercise as medicine.

Reliability and validity of a GPS-enabled iPhone "app" to measure physical activity.

This study assessed the validity and reliability of an iPhone "app" and two sport-specific global positioning system (GPS) units to monitor distance, intensity and contextual physical activity. Forty (23 female, 17 male) 18-55-year-olds completed two trials of six laps around a 400-m athletics track wearing GPSports Pro and WiSpi units (5 and 1 Hz) and an iPhone(TM) with a Motion X GPS(TM) "app" that used the inbuilt iPhone location services application programming interface to obtain its sampling rate (which is likely to be ≤1 Hz). Overall, the statistical agreement, assessed using t-tests and Bland-Altman plots, indicated an underestimation of the known track distance (2.400 km) and average speed by the Motion X GPS "app" and GPSports Pro while the GPSports WiSpi(TM) device overestimated these outcomes. There was a ≤3% variation between trials for distance and average speed when measured by any of the GPS devices. Thus, the smartphone "app" trialled could be considered as an accessible alternative to provide high-quality contextualised data to enable ubiquitous monitoring and modification of programmes to ensure appropriate intensity and type of physical activity is prescribed and more importantly adhered to.