Amount of exercise makes no difference.
I am fairly new to MFP. I am experimenting with changing the amount of exercise and seeing what effects that might have. I have noticed that if I want to lose 5 pounds by January 4, I am allotted 1740 calories per day. Fair enough.
Then I added in playing soccer for an hour 3 times per week. Still 1740 calories allowed per day to lose 5 pounds by January 4.
I then decided to add in playing "competetive soccer" 7 times a week for 300 minutes per day. Still 1740 calories allowed per day to lose 5 pounds by January 4.
I would imagine that playing "competetive soccer" for 6 hours per day, 7 days per week, would cause someone to lose quite a bit more than 5 pounds per month on a 1740 calorie per day diet.
(In fact, I think it it were really possible to exercise this much, you would lose so much weight in a month that you might just disappear altogether.)