If you're trying to lose weight by cutting calories and exersizing, you need to determine a few things first.
How much do you weight currently? How active is your regular (non-workout) life? These two things dictate how many calories you need to survive at your current weight. Then you need to have at least a best guess of how many calories you burn doing your excersize (biking, aerobics, etc).
More on this in a bit.
My daily exersize is to ride my bike on a trainer in the AM, before breakfast, for 30 minutes. It's all the time I have in the AM so it's all I can do. I stay at 80% of my max heart rate for at least 20 of those minutes, warm up for 5 and cool down for 5. I average 23 mph doing this. I burn around 450 calories during this time. I don't eat before and I eat a banana afterward. But I'm losing weight fast for a reason.
Now, so you don't have to give this info, I'll share mine with you and you can fill in the blanks.
I weigh 172 pounds (down 6 in 17 days, down 9 inches also). This means I need 1720 calories a day just to lay in bed and breathe in order to maintain that weight. My days are mostly sitting, so I add only 20% of daily calories for my lifestyle (40% if you are moderately active-a server in a restaurant is mod active, and 70% if you are an athlete). So I would add another 344 calories. This is just to maintain my weight.
So, in order to stay at 172 (no) I would eat 2064 calories.
BUT, I don't want to stay there! I want to be 130 someday. I've decided that I can easily keep myself at 1600 calories per day. Been doing it two weeks and my stomach has shrunk so it takes less to get the 'full' feeling. Since I'm also burning 450 calories a day on the bike, I'm living on 1150 calories a day.
This means I'm in a defecit of 914 calories a day and every 4 days I should lose a pound. And so far it's working well!
Now, as for what to eat after training, it depends on the training. I consider my bike rides aerobic, not weight training (though my legs say different). After aerobic training I eat good carbs (fruit, veggies, yogurt) NO white foods (rice, bread, noodles). After weight training I eat protien. Just note to stay within the set number of calories you've given yourself for the day. Even protein, eaten in excesive amounts, will be held in the bod as fat.
Good luckk and keep us up to date on your progress. It's easier to stay on your own 'diet' when you can see what others are doing!