The TUT for the lower body is generally around 90 seconds. So, one set should last about 90 seconds before hitting muscle failure. That would be 6 reps at 15 seconds each.
man, i was feeling so angry, but now i feel good again.
beyond brawn mentions a pause test, that you can perform once every few weeks or so, where you pause at any point in the motion and hold it there, to see if you're up to it. if you can pause at any point, you are a good man.
Just some food for thought... super slow works almost entirely your slow twitch muscle... (red muscle)
IIRC high weight low rep works both slow and fast (white and red muscle) and has been proven superior. Not to mention the added stress of the weight to your bones to encourage them to become stronger in reaction to the stress.
If you like slow workouts more and keep with it. But I do think high weight low reps is better.
Sorry I do not have citation maybe someone else will. (I am recalling from my old powerlifting days) Also Dr.K loves high weight low rep lifting.
Something I started recently that I like: I was doing BW exercises 3-4 days a week, several sets to failure, 2-3 times a day. Somedays that would mean 50+ chinups, 50+ pullups, 50+ dips, and 100+ pushups. I hit a wall after several months and couldn't increase numbers and was having recovery issues. I've now taken to doing BW once a week, super-slow movements and only 2 or 3 sets of 10 pulls/chins/dips, and 25 pushups. After a few weeks of this I added 5 pullups to my personal best and recovery not an issue.
High weight / low rep training also has the greatest potential for injury. Not worth the risk for someone just interested in improving health, fitness, and general strength. Powerlifters assume the risks in order to compete but health-seekers shouldn't be pointed in that direction without being given all of the facts.
you can always try slow cadence training with body weight exercises too. mark had this as a Workout of the Week sometime in the past year. i don't know that you necessarily need to try 10 second counts, but slow can do you a lot of good. you can easily try pushups, pull ups, squats, inverse rows and some ab work like reverse crunches or dragon flags (crazy hard to do slow i'd imagine). just try and do 5-10 pull ups at 5 seconds up and five seconds down, and see how sore your lats are for the next couple of days.