Even if your strength or something is higher, it will have no effect on your combat.
For example:
If I am 90 range, I would have a combat of about 60
If I am 91 strength, I would have a combat of about 61
If I am 90 range AND 91 strength, I would have a combat of 61, because combat from strength is more than combat from range.
Thus, you will NEVER lose combat levels.