nscrbug, I am glad you getting tested so you can find what your threshold really is. I get tested every few months in order to adjust my threshold power and monitor my fitness. There are few different ways of performing the test, some are highly scientific but most consist of doing a warm up and then a 20 to 30 minute test. To answer your question is most likely that is going to be painful (can very painful) as you have to go as hard as you can for at least 20 minutes. I don't really look forward to test days.