Question

A person with heart disease has a heart that cannot increase stroke volume at all, yet following training they are able to do more work. Explain which adaptations have taken place that allows the individual to do more work.

Answer 1

Ans:- Stroke volume is the volume of blood pumped from the left ventricle per beat.Usually stroke volume is used for left ventricle,but we can use it for both ventricle.It is approximately 70ml in a healthy man having weight 70Kg.The product of stroke volume and heart rate gives cardiac output.
stroke volume= End diastolic volume - End systolic volume.

Stroke volume can be increased by regular aerobic exercise and enable to do more work.stroke volume can be increase by increasing conractility or preload.preload increased by increased respiratory activity,increased skeletal pump activity or by effects gravity.
The adaptions that taken place are as follows:-

No use of tobacco- Chemicals in tobacco can damage your heart and blood vessels. Cigarette smoke reduces the oxygen in your blood, which increases your blood pressure and heart rate because your heart has to work harder to supply enough oxygen to your body and brain.

Daily exercise:- One having heart disease should do 30-60minutes of activity daily.Physical activity helps you control your weight and reduce your chances of developing other conditions that may put a strain on your heart, such as high blood pressure.

Eating of heart healthy diet:- One should eat low fat -fat free diary food,whole grains,olive oils,legumes and limitations in intake of salt,sugar,alcohol.

other adaptations include in traning are:-Choose an aerobic activity such as walking, swimming, light jogging, or biking. Do this at least 3 to 4 times a week.Take rest periods before you get too tired.During hot weather, exercise in the morning or evening. Be careful not to wear too many layers of clothes.