[Athletic drinks: body rehydration as a vital aspect].

106 students of the Faculty of Physical Education and athletes who train at the center of power arts (aged 18 to 30 years) have been investigated. The relation between the amount of lost and consumed liquid during physical activity has been studied. The amount of fluid lost was determined by the method of measuring the body mass of an athlete before and after the workout. The kinds of liquids used for eliminating dehydration have been analyzed. It has been revealed that while doing some physical activity and sports most of those being tested don't restore the lost liquid volume (with an average weight loss of 1,15 kg the amount of fluids they drunk was 0.91 l). In the given research the interrelation between the body weight and the lost liquid amount, and between the lost liquid amount and the kind of sports has not been exposed. Liquid loss of athletes in the medium intensive training process during the period of 1.5 h at the ambient temperature 21-22 degrees C constituted on average 1.53% of the body weight and didn't depend on the kind of sports. Despite the advantages of the athletic drinks are evident, the share of their consumption among the athletes in Russia is negligibly small. The great majority of respondents, namely 72%, use common or mineral water to restore the liquid. Only 6% of those being tested consume specialized athletic drinks.

[Medical and biological basis of the recipe of cultured milk products-containing rehydrating beverage for the athletes].

According to the results of the physic-chemical research the composition of new isotonic rehydrating beverage has been presented and its nutritional and energy value has been calculated. As opposed to other sport drinks of this kind, a part of water in the new product is substituted by whey. From the physic-chemical standpoint whey is a complicated dispersed system in which hydrated proteins are in the form of colloidal solution, lipids are finely emulsified lipoprotein particles, carbohydrate and mineral components are close to the composition in the whole milk. Natural milk whey complex of macro- and trace elements (phosphorus, calcium, magnesium, iron, iodine, zinc, copper, selenium, etc.), most of which are in chelated form, have high biological value and bioavailability for humans. The content of vitamins, minerals, essential amino acids of whey increases the nutritional value of the beverage. Natural sugar syrups--containing of lingonberry, cranberry and rosehip were used to flavor the drink. The new beverage osmolarity is in the limits of 280-350 mmole/l, which allows classifying it as an isotonic sport drink. Natural ingredients and moderate carbohydrate, lipid content, and relatively low energy value enable to recommend this beverage to the athletes of any specialization without any restrictions.

[Macromolecular synthesis and cell division in Escherichia coli in the lag-phase of diauxie]. / Sintez makromolekul i delenie kletok u Escherichia coli v lag-faze pri diauksii.

The pulse incorporation of radiolabelled mannitol, glycerol, thymidine, uridine and protein hydrolysate has been studied during the Escherichia coli growth. The incorporation of carbohydrates and predecessors is sharply changed before and after lag-phase, that is due evidently to the partial synchronization of cell population. Three cell divisions have been found: before lag-phase (determined by the curve of optical density), at the end of it and after it termination. Cell division is accompanied by removal of catabolic repression from glycerol utilization, by increase of protein, RNA and DNA synthesis rates. The rates of biopolymer synthesis decrease sharply at the beginning of lag-phase, but DNA synthesis is going on at a rather high level.