Questions on core body strength training assessment
The whole balancing on a ball, even a half bosu type ball, like a circus act is a joke. Most legitimate strength coaches will tell you so. There's no reason at all for the average person to be put at risk of injury by doing those types of "stunts". Now if you intend on surfing or skateboarding...balance away.
The whole ball thing for anything but crunches is just a gimmick so these so called personal trainers have something different to offer or sale you on. It's something different so people believe it's special.
Sorry, it's a pet peeve of mine (personal trainers that take a class and think they know what they're doing). You want core strength? Save your money and just do some old fashion sit ups, side bends and leg raises, then go grab a big 20 or 30 pound rock and walk around the block with it. You'll beat bouncy boy any day of the week. It just takes some hard work, no classes or balls necessary.
OK, this is just my own observations, but I'm 3.5 yrs out and my balance is better than it was after I initially lost my weight, but still not good. I occasionally get training tips from the Director at our Wellness Center and we were talking about doing lunges. I told him my balance was very good and he showed me some tips (and also agreed that I was "off-balance" LOL). Also, by upper body strength has never been that good, but I've been more consistent with my weight and strength training and am able to do quite a bit more than I could 3 months ago. For me, it's just a keep at it thing.... get some instruction... but in the end do what works for you.... It's different strokes for different folks.... Good luck... Janie 275/235/265 PS and I can't walk 10 steps on the treadmill with any speed involved without at least touching the bars.... LOL