Looking for a great leg extension alternative? Bodyweight Leg Extensions is one of the best quad and leg defining exercises you can do WITHOUT EQUIPMENT!
Squats overall are an amazing workout for the legs and glutes. Every fitness professional around tends to prescribe squats for leg strength as well as for calorie burn, since working your larger muscle groups burns more calories.
Learning the basic squat is your first goal on this front, but once you have the basics, it is important to mix up your workouts and add dimension to the moves.