If, like many people these days, you are desk bound for the majority of your working day the hip flexors and the lateral hip muscle complex is at serious risk of being over tight and/or chronically shortened.
These have the ability to pull your lower back into extension which we don’t want but in running they can also transfer excessive forces to the knees.
Like all tissues in the body muscles will shorten to the shortest length they can get away with. So we have to spend some time working on their length and maintaining a healthy strong muscle length to achieve the best function.
Sitting at the desk or steering wheel for too long shortens the Rectus Femoris, TFL and Sartorius muscles which all prevent smooth hip extension in running
A great way to overcome this is to massage out that tightness on a regular basis.
Have a look at the attached video here for an easy solution to this tightness that can be done at home both prior to and after a run or even on a daily basis to offset your working postural habits.