Cardio Respiratory Fitness
Fitness is the ability to perform physical work. Physical fitness is a required element for all the activities in our life. A physically active lifestyle is the central component for the maintenance of good health. There are many factors like heredity, on a environment; diet, socioeconomic status, and training are known to contribute to the physical fitness of an individual. Cardiorespiratory fitness reflects the overall capacity of the cardiovascular & respiratory systems and ability to carry out prolonged exercises. Therefore, cardiorespiratory fitness is considered as a direct measure of the physiologic status of an individual. The cardiorespiratory fitness of an individual is mainly dependent on lifestyle-related factors such as daily physical activity levels.
A sedentary lifestyle and low physical fitness are the most prevalent modifiable risk factors and predictors of both cardiovascular diseases and all causes of morbidity & mortality. High levels of cardiorespiratory fitness provides strong and independent prognostic information about the overall risk of illness & death, related to cardiovascular cases like hypertension, diabetes, obesity and respiratory problems like chronic obstructive pulmonary disease, asthma etc. athletes are commonly associated with a physically active lifestyle as compare to now- athletes, which is beneficial to fitness. Due to regular exercises, athletes tend to have an increase in fitness level when compared to now- exercising individuals. Exercise and physical activity impact on wellness & fitness.
How to Measure Cardio-respiratory fitness
The most important measure of cardiorespiratory fitness is maximal oxygen consumption or VO2 max. In general VO2 max is determined by the maximal amount of bold the heart pumps per minute (cardiac output) and the amount of oxygen utilized by the exercising muscles (i.e. arterial venous oxygen differences). To measure the VO2 max we can use tests like a stress test, Rockport walk test, and shuttle test etc.
Stress test: in this test person exercises on a treadmill or stationary bike. Person’s ECG and oxygen consumption are measured simultaneously during the exercise.
Rockport walk teat: this test provides an estimated VO2 max which tells how much of oxygen body uses during the exercises. Higher the value indicates higher the fitness level of the person. Top perform the test, warm up and stretch for 10 minutes. Ask the person to walk a mile as fast as possible, and take the pulses for 10 seconds and after that multiply by six and put down the number as well the time the person took to walk the mile in the formula to calculate the VO2 max. A cool down period of 10 minutes should be given.
VO2 max = 132.853- (0.0769×weight)- (0.3877×Age)+ (6.315×Gender)- (3.2649×time)- 0.1565×Heart Rate)
Weight in pounds, for males =1 & females= 0 and Age in years
Benefits of cardiorespiratory fitness:
- Engaging in regular cardiorespiratory activity improves insulin sensitivity and glucose regulation, which decrease risk for diabetes.
- Cardiorespiratory activities help in the conditioning of heart. Particularly activities that raise heart rate for a sustained period of time, helps to improve the heart’s ability to deliver oxygen-rich blood to the rest of body. Regular cardiorespiratory exercises help in lowering resting heart rate, lowers blood pressure and decrease the risk of developing coronary heart diseases.
- As we know high-density lipoprotein level is directly related to the amount of cardio-respiratory Increase high-density lipoprotein score leads to improvement in total cholesterol and gives a good ratio of total cholesterol to high-density lipoprotein i.e lowers the cholesterol level in the body.
- Regular cardiorespiratory exercises lead to increase bone density.
- Improves the quality of sleep.
- Overall regular engagement in activities that increase the cardiorespiratory fitness leads to increase life span of a patient
Modes of Cardio-respiratory Exercises:
There are different modes of cardiorespiratory exercises. Brisk walking, running, treadmill, biking, cycling, swimming, aerobic classes, climbing stairs are few examples of cardiorespiratory fitness.
Guidelines for the recommendation of Cardiorespiratory Exercises: American college of Sports Medicine recommended the following guidelines to improve the cardiorespiratory fitness:
It is recommended that level of intensity should be 60-90% of HRmax or 50-85% of VO2 max. For the person with low cardiorespiratory fitness intensity of exercises should be 40-50% VO2 max.
A person should do the exercises for 20-60 minutes depending on intensity. Schedule the physical activities for most, preferably all days of the week.
Faculty of Physiotherapy