I'm guessing that the zone calculator is meaning that you have 153 lbs. of LBM rather than total optimal bodyweight.
172 lbs @ 11% bf leaves you with approx 153 lbs of lbm (as in weight of everything except fat) and ~19 lbs of fat.
17 total blocks is going to run you somewhere around 476 cals of protein, 612 cals of carbs (assuming you're going straight Zone 40-30-30) and approx 476 cals of fat for a total of approx 1564 cals/day. Round it up to 1600 or so.
Assuming you've got an average lifestyle of a student and don't lounge around all day or work a desk job like me, your maintenance range for calories is likely to be 14-16 cals/lb of total bodyweight. 172 x 15 calories ( to split the difference ) likely falls around 2580. Now, I don't know what Type 1 diabetes may do with that equation in terms of expenditure, but even if you've got a lower overall activity level and/or just have a lower caloric expenditure for whatever reason (thyroid function etc.) and we go with 13 cals/lb we still get 2236 just to maintain.
So, in a very long winded way, I think the answer is neither. If anything your metabolic rate may be slowing a touch due to heavily sub maintenance calories.
Of course, none of this is professional opinion and shouldn't be taken as advice superceding or in place of a trained medical professional
And if you don't think kettleball squat cleans are difficult, I say, step up to the med-ball
- CJ Kim