Well I don't eat spaghetti everyday pre workout but I know what happens. It's a complex carb so it's good to eat pre workout, if your still hungry after the first serving eat another. If you're bulking eat 5 servings if you can. It's actually better to eat all at once rather than waiting 15 minutes to digest something. In reality complex carbs take hours to digest not minute.
You're probably more hungry now because the weight gain shake had more fat in it stimulating CCK and making you feel fuller longer.
Think of it this way, when you eat a complex carbohydrate pre workout it is broken down steadily providing a slow stream of energy for the muscles during running or weight lifting. When you eat a simple carbohydrate pre workout you're spiking blood glucose and insulin levels. This brings all the nutrients into the muscle cells faster than it can escape.
Sweet potatoes are complex and good to eat through out the day. Normal white potatoes are fast digesting and shuold only be used PWO. Eat 6 meals a day.
Hope this helps

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