80/20 Running: Run Stronger and Race Faster by Training Slower

by Matt Fitzgerald

Another simple do-it-yourself method of determining the lactate threshold heart rate is the talk test. The lactate threshold heart rate is associated with the fastest running pace at which a runner is able to talk comfortably. While wearing a heart rate monitor, start jogging at a slow, steady pace. After one minute, recite the Pledge of Allegiance (see Figure 6.3) and note your heart rate. Alternatively, count upward from 120 to 125. Now increase your speed slightly, wait a minute, recite the Pledge (or count) again, and again note your heart rate. Continue in this fashion until talking is slightly uncomfortable. Note your pace at the previous speed when speaking was comfortable or sort of comfortable. Your heart rate at that pace is your current lactate threshold heart rate. Comfortable in this context does not mean that you are able to talk without feeling any sense of dyspnea, or oxygen deficit, but the feeling should be quite mild. Here’s a good rule of thumb: If your breathing returns to its pretalking rhythm by the third breath after you finish speaking, then you were able to talk comfortably. Note that the smaller your speed increases are when you perform this test, the more precise the result will be.