Aims: The types of energetic materials that are presented to active muscles during body activities are very important. This research aimed to compare the effect of interval, continuous and parallel aerobic exercise on urea, uric acid and creatinine of urine level in 24 hours and protein catabolism of adolescents.

Methods: This quasi-experimental research was performed on 12-15 year old student boys from hostelry guidance schools of Gonabad city in 2011-12 educational years and 15 individuals were chosen randomly and entered to the study. Urine samples collected 24 hours before starting exercise and immediately after finishing each exercise method for 24 hours and the level of urea, uric acid and creatinine were determined by photometric method. The protein catabolism level was calculated after each exercise. Data were entered into SPSS 19 statistical software and were analyzed by descriptive statistics and ANOVA test.

Results: The weight and body mass index of samples did not show any significant difference at the first of 3 types of exercises. There were no significant difference between the effect of one session exercise of interval, continuous and parallel aerobic activity on urea (p=0.33), uric acid (p=0.21) and creatinine of urine level in 24 hours (p=0.41) and the balance of protein catabolism (p=0.33) of adolescents.

Conclusion: The interval, continuous and parallel aerobic exercises do not have any effect on urea, uric acid and creatinine of urine level in 24 hours and the balance of protein catabolism of adolescent between 12 to 15 years old.