How persistent is lean mass?

[otolith]

At the beginning of 2016, I lost a lot of weight, starting at about 95kg, and between about March 2016 and March 2018, I spent a lot of time doing resistance training.

I had a DEXA scan in July 2016 and the headline figures were

23.3% fat, 76.4kg total, 17.8kg fat, 3kg bones, 55.6kg lean

I had a repeat scan in October 2016 and the numbers were

18.4% fat, 73.07kg total, 13.4kg fat, 3kg bone, 57kg lean

I continued with the exercise regime for another 18 months, but didn't get round to doing another scan.

Then I moved to the other end of the country from my trainer and my gym, and life happened. Stopped exercising, over the course of 7 years, got fat again.

Started this year at 98kg. Now down to 86kg, losing weight fast, keeping protein intake high but haven't been using resistance exercise and concerned that I might be losing a lot of lean tissue, so booked another package of DEXA scans. New scan results:

22.6% fat, 86kg total, 19.5kg fat, 3kg bones, 63.6kg lean

Tabulated

Date	% Fat	Total	Fat kg	Lean kg
July 2016	23.3%	76.4kg	17.8kg	55.6kg
October 2016	18.4%	73.07kg	13.4kg	57kg
March 2025	22.6%	86kg	19.5kg	63.6kg

I gained a fair bit more muscle mass between October 2016 and March 2018, weighed about 80kg. If I were still carrying the same weight of fat as October 2016 I'd have had exactly the same lean mass I have now, which seems unlikely after 7 years of doing no resistance training. Pretty damn sure I won't look the same when I lose another 6kg as I did then! So I must have been leaner. If I was at 10% fat (and I doubt that I was) I would still have only had about 69kg of lean tissue.

Looking at this, I'm quite surprised that I have not lost more. I expected to be more or less back to square one. Is it normal to still retain so much mass after a 7 year break?

Anyway, adding resistance training back in now, looking to maintain lean mass while I lose another 10kg or so and then adjusting diet and exercise to try to regain.