fueling

I really like complex carbs with good fiber content, prolly my fav b'fast before a run is oatmeal. And coffee, of course...

Most nutriments won't be digested that quickly so what you eat before an "easy" regular workout doesn't matter that much. You have to eat well all day and have enough ressources to optimise your workout, not stack up a few hours before. The exception is long cardio exercise (long run, biking etc.), complex carbs can help.

If you're shaking during exertion, are you sure you eat enough proteins? When I don't, shaking and lack of force is the symptom n. 1, doing a basic plank for a few seconds will be enough to make me shake. It doesn't always mean you lack energy (carbs will give you a quick fix, fats a more steady source), it can be a lack of proteins. Magnesium and potassium imbalance can also make you shaky, as well as cause cramps. And hypoglycemia, but that shaking is different. (Instead of muscles shaking during/because of effort, it's a shaking that won't stop at rest.)

Control your protein intake (throughout the day), specifically.