Calisthenics - How to L-SIT all progressions

l-sit looks like it's easy, but i've been trying to learn this hold for so many weeks now, that sometimes i start to lose hope that i will ever be able to hold it. and these are not my abs that are killing me, these are my quads. i can hold tucked l-sit without much effort, but the moment i extend one of my leg forward its quad immediately tightens and after but a few seconds i have to give up because it feels as if it were to tear itself apart. but seeing athletes such as you who are fighting day and night relentlessly to come where they are and who are still pushing themselves even further with such focus and determination is just the thing i need to cheer me up and find the will to go out and fight with my own weakish body tomorrow again. grazie mille signore e buona giornata!