Premature ventricular contractions can occur in a healthy person of any age, but are more prevalent in the elderly and in men. They frequently occur spontaneously with no known cause. Heart rate turbulence (HRT) is a phenomenon representing the return to equilibrium of the heart rate after a PVC.
Microcycle is the training work unit that can be various on lasting, structure and contents. In praxa microcycles last 2-14 days, but the most often variant is 7 days.ecause of that it can be told that there is no unique, universal microcycle structure that can be thought to be equally good for each possible cases. In the theory of sports training there is multiple microcycles classifications.
Microvilli (singular: microvillus) are microscopic cellular membrane protrusions that increase the surface area of cells and minimize any increase in volume, and are involved in a wide variety of functions, including absorption, secretion, cellular adhesion, and mechanotransduction. Contents.ach microvillus has a dense bundle of cross-linked actin filaments, which serves as its structural core. 20 to 30 tightly bundled actin filaments are cross-linked by bundling proteins fimbrin (or plastin-1), villin and espin to form the core of the microvilli.