Level Mode- How do I choose the right level?

There are 2 smart trainer modes used in the SYSTM app: ERG mode and Level mode. In Level mode, you will need to shift gears to meet the power targets.  Each level is based on a separate power curve that gets steeper faster as the levels increase.  See A Guide to using Level Mode for more details.  Levels 0-3 are usually sufficient for most riders.

How do I choose the Right Level?

There are a few things that you should consider:

1- choose a level that allows you to reach all your power targets for your 4DP profile.  Most people can find one level that will allow this, but it is ok if you're using different levels for different parts of the test.  

2- choose a level that allows you to reach your power targets, plus a bit more or a bit less, at a comfortable cadence.  Each step measured in the previous experiment was done (hopefully) at a cadence of 90.  You can vary the power within the range of that gear by varying cadence.  Slight variations in cadence are the best way to pace Full Frontal or Half Monty.  Shifting gears will produce a large drop or increase in power and will make pacing more difficult.  

Most likely, it will take you a couple of tries with Level mode to figure out which one works best for you. Stronger riders will tend to need the higher levels but many riders will find level 0 or 1 to be sufficient. Each trainer is different, so this is really just a starting point to finding the level that works best for you.