Swimming
In this kind of cyclic exercise, all muscle groups also participate, but due to the horizontal position of the body and the specificity of the aquatic environment, the load on the circulatory system in swimming is less than in running or walking on skis. Somewhat less is the energy expenditure, so to achieve the necessary health effect of swimming, it is necessary to develop a sufficiently high speed at which the heart rate would reach the zone of the training regime( at least 130 beats per minute).Without mastering the correct technique of swimming, it is rather difficult to do. As a result of shortness of breath( pressure of water on the chest) and exhalation, swimming promotes the development of an external respiration apparatus and increases the vital capacity of the lungs.
Specific conditions for swimming( elevated humidity, microclimate of the pool) are especially favorable for people with bronchial asthma. When swimming, asthma attacks usually do not occur, whereas during a run with forced breathing, their probability is higher. Practical absence of a load on joints and a backbone allows to use successfully this kind of muscular activity at diseases of a backbone( deformation, diskogenous radiculitis, etc.).
The power supply of muscular activity during swimming is characterized by a number of features. Already staying in water( without performing any movements) causes an increase in energy consumption by 50%( in comparison with the level of it), maintaining the body in water requires an increase in energy consumption already by 2-3 times, since the thermal conductivity of water is 25 timesmore than air. Due to the high water resistance per 1 m of the distance, 4 times more energy is expended in swimming than when walking at a similar speed, i.ะต.Approximately 3 kcal / kg per 1 km( when walking - 0.7 kcal / kg / km). And because of this, swimming can be an excellent means of normalizing body weight - provided the load is regular( at least 30 minutes 3 times a week).When mastering the technique of swimming, sufficiently intense and prolonged loading, swimming can be effectively used to increase the functional state of the circulatory system and reduce the risk factors for IHD.