Different Hold Durations in Isometric Exercises

Isometric quadriceps exercise: Patients lie in a supine position. A rolled-up towel was put beneath the knee. They were instructed to maximally activate their thigh muscles to straighten their knee and hold the contraction for 5 seconds (Group A), 10 seconds (Group B), or 20 seconds (Group C).

all patients will reciece ultrasound for 5 minutes using 1MHz frequency, 0.8 wc2, 5cm2 head with adequate gel as a coupling medium

all participants will recieve TENS for 30 minutes per session. the parameters will be Burst TENS, with main frequency of 100Hz, burst frequency of 4 Hz, intensity to the comfortable muscle twitch, electrodes size according to the size of the patients knee.