You don't have to do this.
Since 1st Jan, I've lost 7.5lb.
I have been riding to work 28 miles per day in this freezing weather wearing the minimum to avoid frostbite.
More calories lost through windchill and clothing conductivity than the cycling.
I eat 25% of the calories burned, mainly in Protein after the rides and NOTHING before the rides.
I've been in the gym too.
I do three x 20 minute 'hills' sessions.
I am 50 and this morning had my HR at 181 and didn't feel any burn.
G knows where my max is?
The gym bike reckoned I burned 750 kCals total. That's not enough to even consider replacing. What I did was cook some steak mince with a pinch of chilli in it.
Todays session culminated at 425 watts, level 21 'hills' session max. the previous session was level 20 and I was sore a bit afterwards.
No soreness today.
Slimeguide fat% calipers say I've reduced 3% since 1st Jan.
That only equates to 5lb fat loss, so I guess the other 2.5lb is water.
All in all, I feel a lot better for it and aim to get to the gym again tmrw afternoon for another blast.