Introduction: The term “muscle lag” and the more specific term “extensor lag” and “quadriceps lag” have been in use for at least 40 years. Muscle an inability to actively move a joint to its passive limit [5]. Extensor lag accompanying knee lesions is a function of great loss in mechanical advantage of the quadriceps during the last 15 degrees of the extensor range, 60 percent increase inforce being needed to complete the extension [3]. Straight leg raising for increasing quadriceps strength was unable to isolate the vastus medialis from the vastus lateralis muscle [8, 10,12]. Aim and Objective: The objective of this study is to determine the effect of SLR and isometric quadriceps exercise on quadriceps lag of normal health individual. Need of Study: To best of our knowledge no studies have been done on to determine the effect of SLR and isometric quadriceps exercise on quadriceps lag of normal health individual. Methodology: A Total of 60 normal healthy young subjects were recruited for the study. The subjects were divided into two groups. Group A and Group B. Group A 30 subjects were included with their mean age (24.76+3.38) year. Group B 30 subjects were included with their mean age (27.16+3.94) year. A subject was given isometric exercise and Group B subjects were given SLR for 3 weeks. Results: Independent t-test was used between the group A and B before and after exercise. It showed that there was no significant difference between the group A and B before exercise. But there was significant difference between the group A and B after exercise (P < 0.05). Future Research: The present study was done on small sample size. So, future research on large sample population can be done & Present study duration was 3 weeks, so a study of long duration can be done. Limitation of the Study: 1. Since the study was conducted with healthy subject the results can not be readily generalized to a patient population without further research. 2. Since the instrumentation used is a universal protractor goniometer (360o) there are some probabilities of errors in the reading as compared to the method incorporating video imaging technique. 3. The sample size is small. Conclusion: The study has shown that the quadriceps lag can be greater reduce on isometric exercise compare to SLR exercise. So, the study concluded that the Isometric exercise have more effect on quadriceps lag compare to SLR exercise.

Kyewords: Universal Goniometer; Isometric Exercise & Slr Exercise.