If you call digitalWrite() or analogWrite() then the pin will stay in that state until you set it to otherwise.
There might not be any need for a delay, you could just poll your sensors however many times per seond your code runs.
You might run into the circumstance where you want to react faster than 1 loop of your code would take, there are a few ways you could cope with such a situation but I'd wait till it's a problem. (One easy way that might suit might be to not poll every input every iteration).