EFFECTS OF EXERCISE ON CARDIOVASCULAR HEALTH

By: Tim Farren

Thought Questions

Can exercise be bad for you?

What are benefits of exercise to the Cardiovascular system?

How much should one exercise?

Risks of exercise

Increased risk of having a cardiac-related disorder

Including: heart attack, serious heart-rhythm disorder, or even death

Risk is extremely small however

How age effects the risks

The older one is, the higher the risk of an occurring event during or after exercise

1 per 11 million men 20-39 experience problems

1 per 900 thousand men 60-69 Extremely rare in women of all ages

Risks for healthy people

Prolonged exercise can show signs of myocardial fatigue

Complete recovery within a few days Exercise is considered healthy because of

the low chances of events and high benefits

Thought Questions

Can exercise be bad for you?

What are benefits of exercise to the Cardiovascular system?

How much should one exercise?

Major Benefits of Exercise

Reduced blood pressure

Reduced bad cholesterol levels (LDL and total)

Increase in good cholesterol levels (HDL)

Benefits Cont’d.

Exercise also improves the body’s ability to take in and use oxygen.

This can make exercise easier at higher levels, especially for those with cardiovascular disease.

Oxygen Intake

18-25% peak oxygen intake improvement.

18-34% peak exercise duration improvement.

Subjective symptoms, quality-of-life scores, and activity profile have been found better after exercise.

Indirect Benefits

Muscle Strengthening

Lifestyle Change

Muscle Strengthening

High pressure with muscle groups occlude muscle blood flow, increasing after-loading of the heart.

This limits chances of cardiac ejection and stroke volume.

Lifestyle Change

Those who generally exercise tend to include healthier habits in their lifestyle.

Healthier eating, non-smoking, increased water intake.

Causes reduced cardiac risk factors, though the benefits are small.

Direct Benefits

Resting heart rate decrease Reduced blood pressure Increased peripheral venous tone Plasma volume expansion Increased myocardial contractility and

stroke volume

Resting Heart Rate

Increase in parasympathetic nerve activity

Contraction rate of the atria is reduced

Blood Pressure

Resting blood pressure and active blood pressure always lowers from exercise

Caused by strengthening of skeletal muscles

Peripheral Venous Tone

Increased peripheral venous tone from exercise

Increases central blood volume and cardiac stroke volume.

Also reduces likelihood of hypotension after exercise.

Plasma Volume

Early response

Expansion in plasma volume after exercise.

Due to adjustments in the renin/aldosterone system during exercise (Regulates blood pressure and fluid balance)

Myocardial Contractility and Stroke Volume

Exercise increases myocardial contractility.

Boosts oxygen consumption of myocardium.

Can increase cardiac stroke volume by 20% or more.

Leads to increase in functional capacity.

Thought Questions

Can exercise be bad for you?

What are benefits of exercise to the Cardiovascular system?

How much should one exercise?

How much exercise is enough?

At least 30 minutes of modest activity on most or all days of the week

30-60 minutes of continuous physical exercise 3 days a week

How intense?

Exercise sessions of about 60-70% of maximum oxygen intake

Older people can benefit from as low as 40% maximum oxygen intake

Exercise: Last Thoughts

Since chances of risks occurring are low, exercise is considered healthy.

It is important to keep up with exercise, since sedentary lifestyle can lead to increased risk factors.

Bibliography

Anonymous. "Physical Activity Exercise's Effects on the Heart." NY Times. N.p.,

n.d. Web. 10 Oct. 2012. Dimmeler, Stefanie. 2003. Exercise and

cardiovascular health. Circulation. 107:3118-3120.

Myers, Jonathan. 2003. Exercise and cardiovascular health. Circulation. 107:e2-e5.

Shephard, Roy J. 1999. Exercise as cardiovascular therapy. Circulation. 99:963-

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