I'm 43 old and I have practiced martial arts for the last few years. My thighs have strong muscles but I don't think they are strong enough. Some of the practitioners in my martial art have thighs that are strong as iron 'literally'.
Strong thighs are important since we absorb hits using them.
What is the best way to strength the thighs at home with minimal equipment and minimal time (I have dumbbells and Iron Gym Upper Body Workout)? Are there some drills relevant to Body by Science method (Big 5)?