Question

Some people who take beta blockers get out of breath when they exercise.

Explain why beta blockers can have this effect during exercise.
6 MARKS,easy definition to remember

Answer 1

Beta blockers cause shortness of breath during exercise by blocking beta-1 receptors in the heart, which prevents the normal increase in heart rate and contraction force needed to meet the body's oxygen demands during physical activity.

Step-by-step explanation:

Some people who take beta blockers get out of breath when they exercise because beta blockers work by blocking the beta-1 receptors in the heart. These receptors normally respond to adrenaline, leading to an increased heart rate and stronger heart contractions. During exercise, your body requires more oxygen, and thus your heart needs to beat faster to meet this demand. However, with beta blockers preventing this increase in heart rate and contraction force, the body cannot adequately increase blood flow and oxygen delivery during exercise, leading to shortness of breath or dyspnea.

Moreover, the mechanism of action of beta blockers includes the reduction of blood pressure by preventing vasoconstriction and slowing down the heart rate, which is beneficial for conditions like hypertension but can also result in a limited ability to engage in vigorous physical activity.

Answer 2

Beta blockers slow the heart rate, which can prevent the increase in heart rate that typically occurs with exercise. This means that it might not be possible for you to reach your target heart rate, the number of heartbeats per minute you typically aim for to ensure you're exercising hard enough.