The purpose of the study was to assess the flexibility among trained and untrained adolescent boys living at different altitudes of Kashmir region. To achieve the purpose of the study three hundred sixty (360) adolescent boys living at different altitudes of Kashmir region India were randomly selected as subjects .These were divided into two groups trained and untrained, one hundred eighty (180) adolescent boys were selected from trained group and one hundred eighty (180) were selected from untrained group with an age of the subjects were ranged from 13 – 18 years were selected as subjects .The data collected from high, moderate and low altitude adolescent boys for both trained and untrained groups on  selected  variable  flexibility was measured by using  sit and reach test and were statically analysed by using 2x3 factorial ANOVA ( Group x Altitude) whenever the obtained F ratio value for interaction effect was found to be significant the simple effect test was applied as follow test  in all cases the level of the significance was fixed at 0.05 for the test which was considered as an appropriate. The result of the study show that the trained adolescent boys brought significant increase of flexibility on moderate altitude and low altitude have significantly showed increased in flexibility as compared to the trained adolescent boys of high altitude. The result also reveals that the increase in flexibility is significantly more for moderate altitude as compared to low altitude adolescent boys. And also untrained adolescent boys brought significant increase on flexibility of moderate altitude and low altitude adolescent boys have significantly showed increased flexibility as compared to high altitude untrained adolescent boys. Whereas for flexibility there was no significant difference between low and high altitude as compared to moderate altitude adolescent boys.

Key Words: flexibility, trained and untrained, adolescent boys. high altitude, low altitude, moderate altitude