I'm keen on paddle sports

and kayak at every opportunity I can plausibly manage. To support the kayaking, and to maintain the muscle mass that I
do have, I'm currently following
Body by Science as the weight training that I used to do was deteriorating. I also follow a modified version of
Body by You (the women's version of
YAYOG or
You Are Your Own Gym).
Extensive detail to follow that is summarised as, I'm that new bane of Public Health, the TOFI (Thin Outside, Fat Inside), but, I'm working on reducing the fat, so feel free to skip the detail.
My highest weight was 168lbs following an accident that left me abruptly sedentary for some time. I didn't previously have a history of obesity.
I adopted ADF and then 4:3 to shed the excess weight. As I neared my original goal weight of 130lbs, I realised that I must have substantially increased my body fat percentage as I was much larger than I anticipated that I would be. (My body fat used to be <18%.)
So, realising that my goal weight was not a good proxy for my body composition (which I believe is more relevant for me), I had a Bod Pod analysis. I was devastated to discover that at a BMI of <23, I was in the category of Normal Weight, Morbidly Obese (using the classifications suggested by Shah & Braverman): I had a body fat of 42%.
My values were odd because my waist-hip ratio was <0.68 and my waist was reasonably small (<68cms). Nobody believed that I was technically morbidly obese, and well and truly a TOFI and the general opinion was that the analysis must be wrong as I appeared to be slender.
The issue nagged away at me because I was horrified by the 'morbid obesity' of my body composition but more than a little concerned at the (to me) low level of lean body mass (LBM) that I had (the Bod Pod reported it as <77lbs). It took me months to reverse engineer various papers and studies to establish that my reported LBM was low and much lower than anyone else around my age and general habits.
I decided that I should probably maintain my original goal weight for a while before deciding what to do next, so I did. However, I reasoned that if the body composition report was even vaguely accurate then I probably needed to continue to drift downward, reducing body fat but absolutely not compromising my scant LBM.
Eventually, I decided that I could only settle my mind by having the more accurate Dexa scan. I did, and learned, to my horror, that although the Bod Pod had slightly underestimated my LBM, I did still have a low LBM and sufficiently low skeletal muscle that I'm categorised as sarcopenic. By this time, I'd shed an additional 10lbs, so my body fat at 117lbs was approx. 30%, which still counts as obese by some revised categorisations.
Today, I'm 109lbs or <19 BMI. If I've lost no more LBM, I'm still approx. 25% body fat (I can't confirm that until my next scan which is 2015). Ideally, to reduce the metabolic diseases associated with sarcopenia (diabetes, CVD etc.) I'd be no more than 20% body fat but that isn't feasible as I'd need to weigh <100lbs which would make me unsustainably and unhealthily underweight (<17 BMI).
My impression of 4:3 in maintenance is that it's helping me to drift downwards and is removing body fat but not compromising LBM. This remains to be confirmed however and I'm investigating why I lost 30lbs or so of LBM and gained such a vast quantity of body fat.