Tell ya what burns me as badly as anything I have tried is doing leg extensions in combination with jumping lunges.
Example: 8 reps on the leg extension sqeezing hard then onto jumping lunges performing 10 reps on each leg.
WHOOOAAAA!!!
P.S. Watch the knees!!
Do a hard set of front squats with a weight that will allow anywhere from 6-10 reps…then…put the bar back on the rack and immediately get underneath it in the back squat position-do the same number of reps.
Summary:
front squat, 6-10 reps followed immediately by back squats with the same weight for the same number of reps.