Exercise and Performance

Fitness testing 2

Jeri Graham

Bridget Gallagher

Chronic Adaptations to Exercise

The dictionary defines ‘chronic’ as:‘Of long duration; continuing’

Chronic adaptations to exercise are the physiological changes that occur in the body as

a result of training over a period of time, in specific areas.

Chronic adaptations to exerciseCardiovascular

Following training the cardiovascular system and its components go through various adaptations. Here are the most important: ↑ Heart SizeThe heart’s mass and volume increase and cardiac muscle undergoes hypertrophy. It is the left ventricle that adapts to the greatest extent. ↓ Heart RateResting heart rate can decrease significantly following training in a previously sedentary individual. During a 10-week exercise program, an individual with an initial resting heart rate of 80beats/min can reasonably expect to see a reduction of about 10beats/min in their resting heart rate ↑ Stroke VolumeStroke volume increases at rest, during sub maximal exercise and maximal exercise following training. Stroke volume at rest averages 50-70 ml/beat in untrained individuals, 70-90ml/beat in trained individuals and 90-110ml/beat in world-class endurance athletes. ↑ Blood FlowSkeletal muscle receives a greater blood supply following training. This is due to: -Increased number of capillaries-Greater opening of existing capillaries -More effective blood redistribution -Increased blood volume ↓ Blood PressureBlood pressure can decrease (both systolic and diastolic pressure) at rest and during sub maximal exercise by as much as 10mmHg in people with hypertension. However, at a maximal exercise intensity systolic blood pressure is decreased compared to pre-training. ↑ Blood VolumeEndurance training increase blood volume. While plasma volume accounts for the majority of the increase, a greater production of red blood cells can also a contributory factor

Chronic adaptations to exerciseRespiratory

●Slight increase in Total lung Capacity ● Slight decrease in Residual Lung Volume ● Increased Tidal Volume at maximal exercise levels ● Decreased respiratory rate and pulmonary ventilation at

rest and at sub maximal exercise ● Increased respiratory rate and pulmonary ventilation at

maximal exercise levels (because of increased tidal volume)● Unchanged pulmonary diffusion at rest and sub maximal

exercise. ● Increased pulmonary diffusion during maximal exercise.● Increased A-VO2 difference especially at maximal exercise

Chronic adaptations to exerciseMuscular

One of the primary adaptations that the body makes to weight training is muscular hypertrophy, an enlargement of the muscle fiber. When the muscle is stressed, the protective outside covering of the individual muscle fibers gets stretched. This stretching creates spaces where various materials, such as nutrients, can flow in and out.

Another muscular adaptation to strength training is increased strength. Strength is the maximal amount of force a muscle or muscle group can generate at a specified velocity. Typically strength movements are slow compared to other movements because it takes time to generate maximal force

Muscle can also become more powerful through training, particularly weight training.Power is the ability to exert force at a high speed of movement. It requires a lighter resistance and higher velocities than does pure strength training. Someone who is powerful is both strong and quick.

Physiological benefits of exercise for Cardiovascular Health

Increase in exercise tolerance.Reduced body weight.Reduced blood pressure.Reduced ‘bad cholesterol’ (LDL and total cholesterol)Increased good cholesterol (HDL)Increase in insulin sensitivity.Improvements in muscular function and strength.Improvements in bodies ability to take in and use oxygen. (Maximal oxygen consumption or aerobic capacity)

Physiological benefits of exercise for Diabetes

Regular exercise reduces the demand for medication by up to 20% for diabetics.

Physiological benefits of exercise for Diabetes

• Control of blood glucose levels : Physical activity utilizes the glucose and helps to reduce the blood glucose levels.

• Improves cardiovascular function: Exercise increases the cardio-respiratory fitness by;

-Lowering the blood pressure-Lowering bad cholesterol (triglyceride)-Increasing good cholesterol (HDL)

• Psychological Benefit :Physical activity is associated with an increased sense of well being and a positive attitude.

• Weight Control : Physical activity helps obese/overweight individuals to lose weight and maintain a healthy BMI

Physiological benefits of exercise for Asthma

Exercise Induced Asthma (EIA) is triggered through exercise although it is less easily triggered in fitter people

rather than unfit people.

Physiological benefits of exercise for Asthma cont.

Increased cardio-respiratory fitness.Improved exercise endurance.Reduced perception of breathlessness.Reduced anxiety about physical activity.May alleviate asthma symptoms.May decrease the use of oral/inhaled steroids.

Physiological benefits of exercise for Asthma cont.

Most people can still enjoy exercising and playing sport although you need to know your limits. Intense exercise such as running, cycling and team sports are

more likely to trigger EIA compare to less intense sports such as golf or

walking. Swimming is ideal for asthma suffers as the warm humid air generally

reduces the risk of EIA.