Lactate threshold training blocks focus on higher-end aerobic work approaching — and sometimes just crossing over — your lactate threshold (LT). As an endurance athlete, you want to be able to stay aerobic at higher levels of effort. Lactate threshold training helps to improve your lactate tolerance and decrease lactate accumulation, which allows you to stay aerobic at faster speeds.
During this training phase, your key higher-intensity sessions consist of LT cruise intervals of 6-20 minutes in duration with a 2:1 up to 5:1 work to recovery ratio. For example, after you’re warmed up, you might do 4 x 8 minutes in the “comfortably hard” zone with 4 minutes of easy recovery between. Total time at intensity during these workouts can range from 30-60 minutes.
You’ll notice that these workouts are done at a “comfortably hard” effort similar to the aerobic tempo workouts used during the endurance training phase. The differences are that interval length is shorter and the intensity moves closer to — or even crosses over — your lactate threshold.
For the “comfortably hard” lactate threshold workouts, you may be able to say 5-7 words at a time, but will likely need to breathe through your mouth.
Aside from these key intensity workouts, the bulk of your training during this and any phase includes endurance workouts in the “conversational” zone and recovery workouts in the “easy” zone.
Lactate threshold training might span 6-8+ weeks in your training plan.