I have a pair of the Bowflex SelectTech 1090 dumbbells and a bench. They are great for upper-body workouts, but I'm looking for a way to use them for leg exercises as well.
What leg exercises can I do with dumbbells for strength-training?
There are tons of exercises that you can try with just a pair of dumbbells. However, if your goal is for strength training, then you must follow the progressive overload principle, paying close attention to the rep ranges (3-8).
With this being said, depending on the max weight that you have (I believe they go up to 90 lbs), you can try these exercises:
These should be plenty for you to start out with. Again, for strength training, you should aim for 3-8 reps. For muscle hypertrophy, aim for 8-15 reps. For both, then aim for 6-12. Good luck!