Net Calories

The exercise will keep your metabolism going. I wouldn't worry about eating to few of calories those days. It takes a few days in a row of being extremely under calories for your body to kick into starvation mode.

I use a fitbit and it logs all my movement and counts my burn. It encourages me to move more on rest days without the stress of extensive exercise. Raised my overall activity and was able to up my total daily value. Intended to up my sedentary activity to light and light to moderate. You can do this by getting a step counter (very cheap) and using stairs rather than lifts. On exercise days are you confusing BMR with other Calorie measures which include exercise? Add your exercise calories to your BMR to get one measure of calorie allowance on exercise days, which is net calories. You can be consuming calories above or below but in the longer term be spot on cumulatively over a week. The body does not say its midnight lets start again.- yesterdays net was over/under. A day or so of enforced fasting because of illness wouldn't destroy years of work. If you have more rest days then overall you could burn more calories cumulatively by upping general activity on those days. Exercise days are important for intensity, muscle usage, aerobic conditioning etc and I can see you know this. But rest days and general activity are important too.

I don't believe in starvation mode at all but eating long term below BMR is not a good idea as when essential amino acids are reduced there are negative effects on muscle growth and repair. I think I would say move more on rest days and eat more evenly across the days. It iis the overall effect on the body over time that I think is important.
I think of it as a longer term overall pattern- a journey with a trend.


Jasmin

I think it is fine not to eat back your exercise calories. I rarely eat mine back and I am loosing on average 1.8 lbs per week.