Abstract
Background: It is common to use blood lactate for the determination of performance as well as for the development of training exercises in athletes.

Aims and Objectives: The purpose of this study was to gain better understanding of blood lactate concentration which is increased almost 3-4 folds, after the subject complained of subjective feeling of fatigue while exercising on a bicycle ergometer.

Materials and Methods: The study was conducted on 50 adolescent participants of the age group of 16-19 years with body mass index 18-25. Before testing, the participants’ height and weight were measured. Blood pressure (BP), respiratory rate (RR), and heart rate (HR) were recorded in the supine posture, and 2 cc of blood was collected for measurement of blood lactate level. After cycling for some time when the participant complained of feeling of fatigue then the time was recorded and asked to stop exercising then the subject was advised to lie down supine on the bed and one blood sample collected after recording BP, HR, and RR. Data were recorded in the case record form. Paired t-test was used to compare the mean values of parameters before and after test.

Results: Blood lactate levels before exercise with a mean value of 10.1604 mg/dl and blood lactate after exercise with mean value of 33.809 mg/dl. Paired t-test on the computed mean difference between two blood samples at rest and post exercise revealed that they were statistically significant with a probability of P < 0.001.

Conclusion: It is advantageous for clinicians to have a good understanding regarding blood lactate and its clinical implications. While an elevated level may be indicative of ischemia or hypoxemia, it may also be a normal physiological response to exertion.

Key words: Exercise; Fatigue; Adolescents; Bicycle Ergometer; Blood Lactate Level