Exercise Dose in Clinical Practice Wasfy, Meagan M; Baggish, Aaron L
Circulation,
2016-Jun-07, Letnik:
133, Številka:
23
Journal Article
Recenzirano
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There is wide variability in the physical activity patterns of the patients in contemporary clinical cardiovascular practice. This review is designed to address the impact of exercise dose on key ...cardiovascular risk factors and on mortality. We begin by examining the body of literature that supports a dose-response relationship between exercise and cardiovascular disease risk factors, including plasma lipids, hypertension, diabetes mellitus, and obesity. We next explore the relationship between exercise dose and mortality by reviewing the relevant epidemiological literature underlying current physical activity guideline recommendations. We then expand this discussion to critically examine recent data pertaining to the impact of exercise dose at the lowest and highest ends of the spectrum. Finally, we provide a framework for how the key concepts of exercise dose can be integrated into clinical practice.
Millions of individuals have used illicit anabolic-androgenic steroids (AAS), but the long-term cardiovascular associations of these drugs remain incompletely understood.
Using a cross-sectional ...cohort design, we recruited 140 experienced male weightlifters 34 to 54 years of age, comprising 86 men reporting ≥2 years of cumulative lifetime AAS use and 54 nonusing men. Using transthoracic echocardiography and coronary computed tomography angiography, we assessed 3 primary outcome measures: left ventricular (LV) systolic function (left ventricular ejection fraction), LV diastolic function (early relaxation velocity), and coronary atherosclerosis (coronary artery plaque volume).
Compared with nonusers, AAS users demonstrated relatively reduced LV systolic function (mean±SD left ventricular ejection fraction = 52±11% versus 63±8%;
<0.001) and diastolic function (early relaxation velocity = 9.3±2.4 cm/second versus 11.1±2.0 cm/second;
<0.001). Users currently taking AAS at the time of evaluation (N=58) showed significantly reduced LV systolic (left ventricular ejection fraction = 49±10% versus 58±10%;
<0.001) and diastolic function (early relaxation velocity = 8.9±2.4 cm/second versus 10.1±2.4 cm/second;
=0.035) compared with users currently off-drug (N=28). In addition, AAS users demonstrated higher coronary artery plaque volume than nonusers (median interquartile range 3 0, 174 mL
versus 0 0, 69 mL
;
=0.012). Lifetime AAS dose was strongly associated with coronary atherosclerotic burden (increase 95% confidence interval in rank of plaque volume for each 10-year increase in cumulative duration of AAS use: 0.60 SD units 0.16-1.03 SD units;
=0.008).
Long-term AAS use appears to be associated with myocardial dysfunction and accelerated coronary atherosclerosis. These forms of AAS-associated adverse cardiovascular phenotypes may represent a previously underrecognized public-health problem.
Non‐technical summary MicroRNA (miRNA) molecules are essential intracellular mediators of numerous biological processes including angiogenesis, inflammation, and mitochondrial metabolism. Recently, ...it has been shown that miRNAs are secreted into the bloodstream and that circulating miRNAs (c‐miRNAs) may serve important endocrine functions. This study examined plasma profiles of specific c‐miRNAs in healthy competitive athletes at rest and during exhaustive exercise testing, before and after a 90 day period of exercise training. In this setting, we observed four distinct patterns of c‐miRNA response to exercise: (1) c‐miRNAs up‐regulated by acute exhaustive exercise before and after sustained exercise training, (2) c‐miRNAs responsive to acute exhaustive exercise before but not after sustained exercise training, (3) c‐miRNAs responsive only to sustained exercise training, and (4) non‐responsive c‐miRNAs. These findings set the stage for further work aimed at defining the role of c‐miRNAs as fitness biomarkers and physiological mediators of exercise‐induced cardiovascular adaptation.
MicroRNAs (miRNAs) are intracellular mediators of essential biological functions. Recently, plasma‐based ‘circulating’ miRNAs (c‐miRNAs) have been shown to control cellular processes, but the c‐miRNA response to human exercise remains unknown. We sought to determine whether c‐miRNAs are dynamically regulated in response to acute exhaustive cycling exercise and sustained rowing exercise training using a longitudinal, repeated measures study design. Specifically, c‐miRNAs involved in angiogenesis (miR‐20a, miR‐210, miR‐221, miR‐222, miR‐328), inflammation (miR‐21, miR‐146a), skeletal and cardiac muscle contractility (miR‐21, miR‐133a), and hypoxia/ischaemia adaptation (miR‐21, miR‐146a, and miR‐210) were measured at rest and immediately following acute exhaustive cycling exercise in competitive male rowers (n= 10, age = 19.1 ± 0.6 years) before and after a 90 day period of rowing training. Distinct patterns of c‐miRNA response to exercise were observed and adhered to four major profiles: (1) c‐miRNA up‐regulated by acute exercise before and after sustained training (miR‐146a and miR‐222), (2) c‐miRNA responsive to acute exercise before but not after sustained training (miR‐21 and miR‐221), (3) c‐miRNA responsive only to sustained training (miR‐20a), and (4) non‐responsive c‐miRNA (miR‐133a, miR‐210, miR‐328). Linear correlations were observed between peak exercise levels of miR‐146a and (r= 0.63, P= 0.003) and between changes in resting miR‐20a and changes in (pre‐training vs. post‐training, r= 0.73; P= 0.02). Although future work is required, these results suggest the potential value of c‐miRNAs as exercise biomarkers and their possible roles as physiological mediators of exercise‐induced cardiovascular adaptation.
Sudden cardiac death (SCD) is the leading cause of death in athletes during sport. Whether obtained for screening or diagnostic purposes, an ECG increases the ability to detect underlying ...cardiovascular conditions that may increase the risk for SCD. In most countries, there is a shortage of physician expertise in the interpretation of an athlete's ECG. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from abnormal findings suggestive of pathology. On 13-14 February 2012, an international group of experts in sports cardiology and sports medicine convened in Seattle, Washington, to define contemporary standards for ECG interpretation in athletes. The objective of the meeting was to develop a comprehensive training resource to help physicians distinguish normal ECG alterations in athletes from abnormal ECG findings that require additional evaluation for conditions associated with SCD.
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