How do I coordinate the timing of diet and exercise ?

My research is showing I need to consume 2200 calories a day

divided up into 5 or six meals. I am trying to regain both

cardio/vascular and muscular conditioning.

I am 70 years old and after an active life I

lost near total use of my right leg two years ago.

I had been doing lots of work getting the

garden ready. This included a lot of time

spent on the cold damp ground on my knees.

Nearly 50 years ago I had major knee surgery

done on my right leg by the Navy.

They told me it would be an ever increasing

problem as I aged. Other than a couple of minor

flareups probably weather related I had

seemingly out grown any pain or swelling problems.

Then bam The pain was very unpleasent,

and placing any weight on the right leg was

impossible.The swelling increased daily.

I had the knee drained of the excess fluids

which were clear and uninfected . But I still

was nearly immobile for nearly a year.

the next year I recovered gradually to the point

I could persue recovery more vigorously.

However my long period of inactivity had robbed

me of my endurance. Little effort left me perspiring,

with pounding heart, and breathless to an alarming extent.

My weight needless to say had increased better

than fifty pounds. Now I'm able to persue an

exercise program with gradually increasing goals.

However as I try to incorporate the diet portion

of the program I find few guides for the

coordination with eating and exercise.

I have been working on a daily routine for both

I have the morning walk planned as one of

the first activities of the day. (Brush teeth,

put on coffee, walk .)This way my self discipline

seems to fare better. The diet suggestions

I'm working from say eat within the first hour

of rising. What conflicts can I expect when

eating and exercising almost simultaniously ???