Published: 2017-01-02

Cardiorespiratory responses to moderate exercise and determination of aerobic power in first year medical students

Subha Kavundapadi Chandrasekaran, Rajkumar Devaraj


Background: Cardiovascular and metabolic disorder has become common in individuals leading a sedentary life. Exercise stress tests are carried out as part of the investigations for determining the individual fitness level. Aerobic power or VO2max which involves a full functional support from cardio respiratory and metabolic pathways is an appropriate test to study cardio pulmonary fitness. The main objective of the study is to find out the normal cardiopulmonary responses to exercise and their aerobic power among untrained 1st year medical students by Astrand 6 minute cycle test.

Methods: All participants who were not undergone any physical training was taken for the study. Students with history of any respiratory or cardiovascular disorders, any lower limb surgery, smoking and drinking alcohol were excluded. Cardiorespiratory changes associated with exercise were studied using bicycle ergometer. VO2max was determined from the heart rate noted at the end of 6 minutes cycling by using Astrand-Rhyming nomogram.

Results: Heart rate, systolic blood pressure and respiratory rate increased with exercise, while diastolic pressure recorded a fall. VO2max   in male students mean 2.973±0.245, in female students mean 2.665±0.305. The VO2maxis thebest physiological indicator of a person’s capacity to continue the severe physical work. From this we can set a norm in assessing physical fitness and the test can be used as screening measures before joining in a job or sports training.

Conclusions: Aerobic power or VO2max or physical work capacity which involves a full functional support from cardiorespiratory and metabolic pathways is an appropriate test to study cardiopulmonary fitness. Implication:  Astrand 6 minutes cycle test  can be used for screening measures before joining in a job or sports training where physical fitness is needed.



Bicycle ergometer, Astrand-Rhyming nomogram, VO2max

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