One of the best measures of cycling/running fitness is lactate threshold (LT), which is the pace, power or heart rate at which lactate — an intermediate product of aerobic metabolism in the muscles — begins to accumulate rapidly in the bloodstream. If your training program is working, two things are sure to happen. One is that you will be faster at the point where your blood lactate level spikes. The other is that your heart rate at this threshold will increase (i.e., your lactate threshold heart rate will move closer to your maximum heart rate).

In addition to being useful as a measure of fitness, lactate threshold is also useful for establishing individual intensity zones for training. That’s because LT happens to fall at a moderate intensity level. Efforts that are more than a little faster than the pace or heart rate that corresponds to LT are defined as high intensity and offer a different set of benefits than moderate-intensity training. Efforts that are more than a little slower than the pace or heart rate that corresponds to LT count as low intensity and offer yet another set of benefits.

This service is for local athletes, those within an hour driving distance and best done in conjunction with a NIX hydration test.