The rack deadlift is great for lifters with less range of motion, but can also be used to work the top range of the deadlift with a heavier load.
Typically, the rack deadlift is set up with the bar just below the knees, but just above the knee is fine too. If you don't have a rack, use a few 45 pound Olympic plates to elevate the bar into position.
How many reps can you do for two alternating exercises in 15 minutes? This is just a taste of how escalating density training works. It’s a brutal, but fun way to build muscle and improve conditioning.