PHYSICAL EDUCATION DEPARTMENT 3rd ESO

UNIT 5: THE HUMAN BODY. CARDIORESPIRATORY SYSTEM

1. INTRODUCTION

Cardiorespiratory system is the responsable of the endurance capacity. The system is composed by the cardiovascular system and the respiratory system.

2. RESPIRATORY SYSTEM

Its main function is gas exchange between the body and the atmosphere. Respiratory System removes no necessary gases (CO2) and it catches oxygen (O2) from the air needed by cells.

2.1. BREATHING

Breathing is the process of gas exchange between the body and the atmosphere.

Breathing process has two phases: ventilation and diffusion.

Ventilation: this part has two phases.o Inhalation: air is sucked from the atmosphere into lungs (alveoli). o Exhalation: the process of breathing out CO2 from lungs (alveoli) to

atmosphere.  Diffusion: is the process of gas exchange (O2 and CO2) between alveoli from

the lungs and capillary from the circulatory system through alveoli membranes.

2.2. RESPIRATORY RESPONSE TO EXERCISE

During the physical activity we increase the number of breaths per minute and how deep they are. The volume of air that is inhalated and exhalated increases.

Lung Volume: is the volume of air inhalated or exhalated in each breath.o Rest: 0,5 litres.o Physical Activity: up to 3 litres.

Breath Rate: is the number of breathings per minute.o Rest is about 16-20 breaths per minute.

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PHYSICAL EDUCATION DEPARTMENT 3rd ESO

o Physical Activity it increases to 30-50 breaths per minute .Lung capacity: is the maximum amount of air that can fill the lungs. o Non smoker person is about 3-4 litres o Smoker lung capacity is arround 1-1,5 litres.o Athlete lung capacity is 7 litres.

To breathe correctly is very important for physical activity and it delays fatigue. It is very important to inhalate through the nose and exhalate through the mouth and to keep an uniform respiratory rythm.

3. CARDIOVASCULAR SYSTEM

The main function of this system is to transport nutrients and oxygen to organs and muscles and to transport waste products (CO2) to the liver, kidneys, and lungs.

3.1. ANATOMY OF THE HEART AN HEART MOVEMENTS

The human heart is an organ that pumps blood throughout the body via the circulatory system, supplying oxygen and nutrients to the tissues and removing carbon dioxide and other wastes.

The Heart has two movements to pump blood: systole (contaction) and diastole (relax).

Atrial Systole: atrium contacts to push the blood into the ventricle while ventricle diastole.

Ventricles Systole: ventricles contracts to push blood to every cells of the body or lungs while atrium diastole.

3.2. CARDIOVASCULAR RESPONSE TO EXERCISE

Physical activity increases the cardiovascular system activity because: Increases the Heart Rate.

o Maximum Heart Rate: 220-ageo Rest Heart Rate →sedentary people 60-90 bpm

→athletes 40-60 bpm Increases the Stroke Volume (volume of blood pumped by left ventricle of the

heart with each beat=Volumen Sistólico)o Rest Stroke Volume: 75 militres.o Active Stroke Volume: →sedentary people: 140 mililitres.

→athletes: 190 mililitres. Increases the Cardiac Output (amount of blood pumped by the heart per

minute= Gasto Cardíaco)= Stroke Volume x Heart Rateo Rest Cardiac Output: 5-6 litreso Active Cardiac Output: 15-20 litres

Increases the Coronary Flow (blood that flows to the cardiac muscle, myocardium)

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PHYSICAL EDUCATION DEPARTMENT 3rd ESO

Increases the blood flow to muscles.

When we practice exercise changes the distribution of blood flow in our body. Rest: 20% of blood flows to muscles Physical activity: 80% of blood flows to muscles.

The only organ that needs the same quantity of oxygen everytime is the Brain.

VOCABULARY:

Inhalation: inhalar, inspirar. Exhalation:exhalar, espirar Rib cage: costillas Lungs: pulmones Liver: hígado. Kidneys: riñones Breathe rate: frecuencia respiratoria.

Lung capacity: capacidad Pulmonar Heart Rate (HR): frecuencia cardíaca. Rest Heart Rate: frecuencia cardíaca en reposo. Stroke Volume: volumen sistólico. Cardiac Output: gasto cardíaco. Coronary Flow: flujo coronario.

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