Adding on to DPGfitness, he didn't mean that fruits aren't a good thing to eat, trying to take away the knowledge that we gain from our parents since we were wee little about fruits and veggies being good for you. It is just the way in which your body processes carbohydrates. Simple and complex carbs are absorbed in different ways, complex carbs should be the majority of your carb intake even in general, not just for this goal you are trying to reach. Simple carbohydrates are absorbed quickly, which is good when you need to use energy now or asap, but as he said if it isn't used... Sweet potato has a high source in complex carbohydrates, which is why he suggested that.
I don't quite know 100% why he said bananas, but my guess is for the electrolyte potassium balance. An imbalance in your sodium/potassium content (which is very vital to cells) can cause cramping and a bunch of other things. But if you are going to eat that banana, this would be hard to manage, but if you are trying to take it to ensure you won't have any issues when you work out, you'd have to eat it about 2ish hours before you start exercising because it isn't as if your body would absorb the potassium right then and there as soon as you take a bite.
Sports drinks, or other electrolytic drinks, are not necessary unless you are doing intensive exercise for at least an hour. Your body generally has enough and won't need replenishment for anything under that time unless you have poor electrolyte imbalance from the start.
EDIT: Right, I forgot to mention this. You should continue to find ways to alter your work outs, it is a necessity for people continuing to work out long term. Adjusting settings on the machines you are using as you stated in your last post is one method, but I encourage you to go further on as time goes by. We truly do not know just how great our body is, and how little we know about it. Remember, or learn, that your body is a highly efficient machine that adapts to pretty much any changes given enough time and considering that you don't die as a result of the change. Within a few months, if you generally do the same work outs, your body undergoes what is known as habituation, which generally means the diminishing of a response to a induced stimuli as time goes on. To say this bluntly and for the sake of making things easier to understand, your body is your goal's enemy in this case, because as time goes on, and it gets used to the work out, your body will attempt to produce as little energy expenditure as possible. Meaning that during the beginning of your training days, your body isn't used to/capable of handling the task at hand and uses up a lot more calories, but once it gets a hold of things, I guess you can say it tries to give exact change (for the energy requirement). It sucks in this case, but I always say that your body was suited and made to survive to any situations you may experience in your life time, not look good for the summer.
Hope I provided some useful info, good luck!
