Originally Posted by
Carbonfiberboy
Same thing with barbell squats, known as butt wink. Don't go that low.
I've started doing high rep kettlebell swings for hams and lower back. Never did them before, but they're a great way to increase strength and conditioning at, AFAIK, no injury risk. I'm doing sets of 25 and hope to go up in reps from there. Glutes, back, and hams say OW, so I guess they work.
I had to quit doing one-legged presses because I damaged something in one of my feet, maybe because it's not a natural stance, like squatting. Plus I was only going down to 90° (not rounding my back), plus only doing 6 reps. It's OK now but I still feel it a little sometimes. We hope we're always learning before it's too late.
I would be careful with KB swings. You're generating a lot of force when you decelerate these which, coupled with fatigue from doing high reps, could make it easy for your form to break down. Not saying don't do them, or that they are a bad idea, but don't think there is no injury risk either.
In general, high reps can be fairly risky due to the large amounts of fatigue involved near the end of the set. Also, it's far easier for one's concentration to lapse over a 20 rep set than over a 5 rep set.
One other thing to consider: while a 20 rep set may have the same potential for hypertrophy as a heavy 5 rep set, it's far easier to do multiple heavy sets of 5 than multiple sets of 20 with a lighter weight. There's a reason sets of 20 squats are called "widow maker". If you're doing them heavy enough, your day is pretty much done after one of these. The cost/benefit just isn't there in most cases.