I agree that 1400 could be ok, and I wouldn't go lower. If you are going to add significant exercise, you could start higher. You can always adjust. But your body adjusts your metabolism down when you eat less, and up when you eat more. You can obviously overwhelm that feedback by eating way too little and starving to death, or eating too much and gaining, but it's definitely worth eating as much as you can lose weight on.
If the 30DS makes you sore, don't be surprised if the scale stays the same or even goes up the first week. Sore muscles can retain water, but you're still losing fat! It will start dropping again
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