Hip flexor

[barryc108]

Hi,
I started working in a seditry office type job about 2 months ago. In this time i have noticed my hip flexors tightening up significantly. This has also began to restrict other aspects of my flexibility.
I get up and walk around as much as i can without looking like a slacker. I also do the standard lunge stretch with out much luck. I cant really see a way of stretching my hip flexors while seated.

Does anyone have any suggestions?

Thanks