I read this on ratemybody.com (its a rating site, not a work out one) but it caught my intrest.
It was posted by someone name ironwarrior
" Ahh!! Welcome to my world. The benefits are enormous as you will see increased strength, vascularity, muscle fullness, and muscle endurance.
The #1 reason for the 50-rep set is to work the slow twitch muscle fibers. Slow twitch muscles rarely come into play during traditional training in the rep range of 1-20. You usually need to exceed around 35 reps in a constant controlled motion to cause hypertrophic stimulus of the slow twitch fibers.
Speaking of the motion, it should be the same speed throughout the set, with the last few reps being very difficult. When I do the set of 50 on squat, I maintain the same moderate rate throughout the set until I fail or reach my goal. This is key for stimulating the slow twitch muscles.
NOTE: of ALL the bodyparts to use this methodology, squat is FOREMOST. You will see a change literally overnight. Squat is the most anabolic exercise and megareps sets of squats work miracles. I have tested this many times with a wide selection of people and those that stick with it are amazed at how they get stronger in all lifts from the mega squat reps.
Speaking of the squats, the guideline is 1/2 your bodyweight with depth to be 3/4 to full parallel. You can go deeper but it's not necessary and some people have prexisting joing conditions that prevent excessive depth. When you can complete the set with 1/2 BW, increase the reps up to 100 or increase the weight.
In the past, I've done 135 for 100 reps, 225 for 50 reps, and 135 for 50 reps below parallel.
Currently, I got away from them just for something different and regret it as I look flat. I'm starting back up today.
Has anyone tried such a thing? I was thinking of trying to do 50 squats with a light weight on my leg day to see if it "increases vascularity" as he puts it.