Connection between the Body's Systems and Physical Activity

Connection between the Body's Systems and Physical Activity

Introduction

Cardio-vascular system

The cardiovascular system consists of three elements:

The blood - a fluid that circulates for the body and substances which leads to the cells and removes other;

The blood vessels - conduits through which blood circulates;

The heart - a muscular pump that distributes the blood flow in the vessels

The cardiovascular system can distribute the substances throughout the body more rapidly than can do the diffusion, since the molecules in the blood move within the circulating liquid as the particles of water in a river. Into the blood stream molecules move faster because they do not proceed at random, back and forth or zigzag as in the spread, but in a precise and orderly.

The circulation of the blood is so crucial to our existence that if the blood flows to a certain point to stop, loses consciousness within a few seconds and/or after a few minutes. Of course, the heart has to perform its function continuously and properly, every minute and every day of our lives.

Lymphatic System

Little known, but very important, the lymphatic system allows the sap to flow into body tissues, draining every corner of the body before flowing into veins chest. Parallel to the cardiovascular system, the lymphatic system is opposed to excessive accumulation of fluid in the tissues and is considered the bulwark of our body. Along the lymphatics, in fact there are organs called lymph nodes , capable of producing so-called lymphocytes, a special series of white blood cells deputy elimination of hostile microorganisms . When the body is fighting an infection the lymph nodes accelerate the synthesis and transformation of these cells, thus increasing in volume and becoming noticeable and painful to the touch (hence the expression "have swollen lymph nodes").

The lymphatic system consists of an articulated system of vessels, very similar to the venous and arterial circulation. Unlike blood, lymph not pushed back by the cardiac activity, but flows in the vessels moved by the action of muscles. Contracting and relaxing, these tissues function as a real pump. When such action is less, for example due to excessive immobility, lymph tends to stagnate, accumulate in tissues. This explains why the feet and ankles swell when it is long-standing in a static position. For the same reason, when the leg is immobilized by a cast must keep it raised above the level of the heart (just to make sure that the force of gravity assists the lymphatic drainage).

Discussion

Physical Activity and Cardiovascular System

The heart has four fundamental properties:

The ability to contract;

The ability to stemming to certain heart rates;

The ability of the myocardial fibers to transmit to its neighbors electrical stimulation received, taking advantage of preferential conduction pathways;

The excitability, i.e. the ability of the heart to respond to the electrical stimulus that has been administered

The cardiac cycle is the time that elapses between the end of a cardiac contraction and the beginning of the ...