With the current firmware, Stryd will give you power while hiking. You might find yourself running uphill at a slow pace (cadence > 130 SPM) where you could walk at the same pace (cadence < 130 SPM). Once you switch to walking, you will see your power drop. This is expected as walking will be more efficient in those circumstances (and is mechanically different).
We validated walking power with VO2 measurements (just like we did for running), although on a treadmill (since VO2 measurements on trail are difficult).
The Stryd platform will calculate the RSS while you are walking, but likely the RSS will be a low number as your power will be lower than when running. Walking will be in Zone 1, so even long walks will have a low RSS.
RSS is based on critical power, which is the running power you can sustain for a 10k. We currently do not have a good way to determine your critical power while walking.
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