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Micro ribonucleic acids (miRNAs) are small non-coding RNA molecules that control gene expression by translational inhibition. Exercise has been shown to affect several miRNAs' expression in healthy subjects, but this has not yet been studied in patients with coronary artery disease (CAD). Since exercise training confers beneficial long-term effects and may also trigger acute coronary events, it is of utmost interest to be able to identify those who are risk for untoward effects. Therefore, we set out to assess miRNA expression in response to maximal ergospirometry in patients with CAD. Total RNA was extracted from blood drawn immediately before and 5 min after maximal cycle-ergospirometry (10 male and 10 female CAD patients). A qRT-PCR was performed for 187 target miRNAs associated with endothelial function/dysfunction, cardiovascular disease, myocardial infarction, and sudden cardiac death. In response to a maximal ergospirometry, 33 miRNAs significantly changed their expression levels. Of these miRNAs 16 were significantly differently expressed between gender. Using multi-variance analysis, nine miRNAs (let-7e-5p; miR-1; miR-19b-1-5p; miR-103a-3p; miR-148b-3p; miR-181b-5p; miR-188-5p; miR-423-5p; miR-874-3p) showed significantly different responses to maximal ergospirometry between genders. We report for the first time that in patients with CAD, miRNA expression is amenable to maximal ergospirometry and that the extent of changes differs between genders. Affected by exercise and gender were miRNAs that are associated, among others, with pathways for glucose metabolism, oxidative stress, and angiogenesis. Future studies should assess whether disease-specific miRNA expression in response to maximal exercise might serve as a marker for patient outcome. [ABSTRACT FROM AUTHOR]

Sedentary lifestyle predisposes to endothelial dysfunction, increased arterial stiffness and cardiovascular diseases, all of which can be positively modified by regular physical exercise training. A decrease in physical activity during winter months coincides with higher rates of cardiovascular events. In order to identify winter sports suitable to overcome this seasonal exercise deficit and thus contribute to cardiovascular health, it was the aim of this study to compare immediate effects of cross-country skiing (XCS) and alpine skiing (AS) on arterial stiffness as an alternative to indoor cycling (IC). After baseline assessment, eighteen healthy subjects performed one session of XCS, AS, and IC in randomized order. Pulse wave analysis was conducted (Mobil-o-Graph®) before and 10-min after exercise. Parameters of arterial stiffness and wave reflection were reduced after XCS and IC, but not after AS: central systolic blood pressure (IC: -8.0 ± 5.4 mmHg; p < 0.001), amplitude of the backward pressure wave (IC: -1.4 ± 2.7 mmHg; p < 0.05), reflection coefficient (XCS: -6.0 ± 7.8%; IC: -5.7 ± 8.1%; both p < 0.1), and pulse wave velocity (IC by -0.19 ± 0.27 m/s; p < 0.01). Higher exercise intensities correlated with greater reductions of arterial stiffness (all p < 0.05). Single sessions of XCS, IC but not AS led to comparable improvement in arterial stiffness, which was even more pronounced during higher exercise intensities. With regard to arterial stiffness, IC and XCS emerge as more effective to counteract the winter exercise deficit and thus the deleterious cardiovascular effects of a sedentary lifestyle. [ABSTRACT FROM AUTHOR]

Since physical inactivity especially prevails during winter months, we set out to identify outdoor alternatives to indoor cycling (IC) by comparing the metabolic and cardiorespiratory responses during alpine skiing (AS), cross-country skiing (XCS) and IC and analyse the effects of sex, age and fitness level in this comparison. Twenty one healthy subjects performed alpine skiing (AS), cross-country skiing (XCS), and IC. Oxygen uptake (VO2), total energy expenditure (EE), heart rate (HR), lactate, blood glucose and rate of perceived exertion (RPE) were determined during three 4-min stages of low, moderate and high intensity. During XCS and IC VO2max and EE were higher than during AS. At least 2i4 hours of AS are necessary to reach the same EE as during one hour of XCS or IC. HR, VO2, lactate, and RPEarms were highest during XCS, whereas RPEwhole-body was similar and RPElegs lower than during AS and IC, respectively. Weight adjusted VO2 and EE were higher in men than in women while fitness level had no effect. Male, fit and young participants were able to increase their EE and VO2 values more pronounced. Both AS and XCS can be individually tailored to serve as alternatives to IC and may thus help to overcome the winter activity deficit. XCS was found to be the most effective activity for generating a high EE and VO2 while AS was the most demanding activity for the legs. [ABSTRACT FROM AUTHOR]