If I do an intense cardio workout (plyometrics) then eat meat loaf is there any point in working out? ?

As long as you burn more calories than you take in, then it's still worth it. I would recommend exercising after eating [and digesting, don't want to throw up! :P], because you would feel more satisfied knowing you just burned off that meal. If you did before eating, you wouldn't feel like it was worth it