It's super important to remember that the Hex is measuring the SmO2 in one muscle location. So there may be times when you are working out and the trend in SmO2 is not agreeing with how hard you're pushing. Think about where you are wearing the Hex (likely the quadriceps muscle group) and what other muscles you may be using. For example, you could be walking up a very steep incline and engaging your calf muscles much more and the SmO2 in the quad doesn't change much. Or if you have experienced an injury in the past and tend to overcompensate during some activities by using certain muscle groups more than others, that could also explain it. Either way, feel free to email us at email@example.com if you want to talk more about the specifics of your measurements!