Nathan Epler's go-to exercises to build huge quads and calves 

Nathan fuels his intense leg workout with 1.5 scoops of Grape Bubble Gum HOSSTILITY complete all-in-one pre-workout.

Standing Calf Raise
Nathan starts with calves every leg day to ensure that they are trained intensely and not left as an afterthought at the end of a leg workout. He has found that this approach has helped to bring up lagging calves. He performs 3-4 sets of 15-20 reps each. On the last set, he does a triple drop set. He takes the set to failure at 15 reps, drops weight and goes to failure again, then drops the weight a second time and goes to failure again.

Leg Extension
Nathan uses leg extension to warm up the knees and pre-exhaust his quads before moving on to bigger compound movements. He does 2-3 working sets. In the first set working set, he takes to failure at 15 reps. On the last set, he performs cluster sets where he reaches failure at 15 reps and rests for 8-10 seconds. After the brief rest, he will take the set to failure again and repeat this process again.

Pendulum Squat
Nathan positions his feet near the lower middle point of the platform, with a stance about shoulder width apart and his feet slightly pointed outward. Nathan performs two working sets achieving failure at 10-12 repetitions. His first failure set is at his peak weight and takes the set to failure. On his second working set, he reduces the weight by approximately 25% and takes the set to failure again. On this set he increases intensity by doing slow and controlled 3-second negatives on each rep.

Wide Stance Leg Press
Nathan sets his feet low on the platform with his feet positioned to the widest point possible with his feet tracking out towards the shoulders. Doing so allows him to emphasize the quad sweep and adductors more. Nathan does a feeler set ad 3-6 reps to feel the weight up until reaching his peak weight. Once he is at his working weight, he takes two sets to failure at 15 reps.

Dumbbell Walking Lunges
Nathan finishes almost every quad workout with weighted walking lunges. He performs walking lunges with a dumbbell in each hand. As he steps forward, he bends his front knee and brings his back knee down towards the floor before explosively driving up and swinging his leg to perform the same exercise on the next leg. He performs these back and forth on his turf area of the gym. He completes approximately 10-12 lunges per leg on each pass. The key to this is not worrying about speed and ensuring that each lunge is executed properly. You should think of this as a split-leg squat than a forward-moving movement. You are not trying to drive the knee over the toes but down and up.