if your going 2 run, run 4 a good 30 mins at a medium speed ,ur sure 2 burn a lot more than jus 100cals
n its ok 2 eat loads if its healthy just dont snack on junk food :D
do sit ups 2 tone ur stomach nt sure bout the rest
And I see the support just keeps coming...
Kiera -- first of all you know that one day of no deficit just means no loss, no gain -- that's all, not the end of the world. You have to have faith, you need to know that you are strong enough to do this and get past the hard parts -- it will be worth all that much more to you when you look back. And you know that for your body, you can't exist easily on 1200-1400 a day and still be able to be energetic and get a workout in.
To build muscle in any form requires strength movement -- if you "don't build muscle easily" it may take you longer than others, but it's not impossible, and you need muscle to look toned. Therefore, to look toned you will need calories and exercise.
To build muscle you need a caloric excess, not a deficit. If 1650 is maintenance for you, try eating within about a 200 calorie range (some days over, some days under). And instead of running for cardio (which will just burn the calories that you need to build muscle), try some strength training. Weights are good, or try yoga or pilates.
Don't feel bad about one day, because it really IS just one day. You would have to eat 3500 EXTRA caloies just to gain one pound, and I promise you didn't eat nearly that much. Tomorrow is a fresh start, and I wish you the best of luck!
By not gaining/losing, you arent undo-ing all the hard work you have done...so there isnt really anything bad about it.