This was 1 of the 3 exercises I did today in my 12 minute workout . I started with the leg press at 505 lbs for 50 reps, then moved over to calf machine 210lbs for 250 reps, finishing with leg extension on hammer strength 40 lbs for 100 reps each leg. I was in a time crunch so i did a crazy 3 set routine that got me in and out of the gym barely being able to walk. After the workout I literally could not stand up straight, walking later in the day was very difficult