A tempo run is a type of running exercise that consists of a warm up period, a running period done at a comfortably difficult pace and a cool down period. The length of a tempo run varies based on the runner.
A 20 minute running period consisting of approximately 2 to 3 miles is the recommended distance for runners seeking general fitness benefits or preparing for a 5K. 4 to 6 mile running periods are recommended in preparation for a 10K, 6 to 8 mile periods for a half marathon and 8 to 10 mile periods for a marathon. Warm up and cool down periods consist of 5 to 10 minutes of light running. Methods for a runner to determine an appropriate pace include adding 10 to 40 seconds to the runner's best racing pace or running at 85 to 90 percent of the runner's maximum heart rate. Another indicator of intensity is a runner's breathing pattern. A runner typically inhales for three steps and exhales for two steps at lighter intensities. The appropriate pace for a running period is inhaling for two steps and exhaling for one. Tempo runs improve performance because they increase the lactate threshold, which is the amount of lactate and hydrogen ions a runner's muscles can use. These ions are released during running and make the muscles acidic, causing fatigue. Another name for tempo runs is lactate threshold runs.