The lactate threshold is lower for cycling than running. Is this the case with the MAF HR?

The anaerobic threshold is influenced by a lot of other factors, such as perceived exertion, and isn’t a great measure of the aerobic metabolism as we describe it. However, perceived exertion will be very different between running and riding, for example. One will feel cycling at their MAF HR is harder than running at the same rate, yet both activities are building the aerobic system and improving fat burning in a very similar way.

Because perceived exertion changes with different stresses (such as those incurred by different sports), some sports will have different anaerobic thresholds. However, the functioning of the aerobic system—the MAF heart rate—is a primary measure of the metabolism. This means that the metabolic training at a certain heart rate will be the same, but the rate at which lactate is being broken down may be different between sports.