Two loops can run simultaneously if there is no data dependency between them. My guess is that you have a wire going from one loop to another. This establishes data dependency because the loop that is receiving the wire cannot run until there's a value on that wire, and the value on that wire is not placed until the first loop finishes.
That said if you still want to use 2 loops you can pump your data into some "container" and the other loop just read it out. For example, you could use a queue. You can also do this in one loop. If your data acquisition loop is running once a second, then you just need to save the data every 10th iteration. You can simply look at the "i" terminal, which is the iteration count (which starts at zero).