This refers to a level of exertion where lactate, a compound produced when your body breaks down carbs for energy, accumulates in your blood faster than it can be processed out. Lactate’s role in endurance exercise isn’t 100 percent understood. But since it’s consistent and quantifiably measured, its threshold has been used as a marker to set training zones for many years.
Training in this space is still aerobic, but it allows you to maximise your training effect with shorter interval workouts. For this reason, it is useful for athletes training for any distance triathlon and can be used throughout the year.
Efforts from 8–30 minutes in duration with 25 percent rest are considered threshold training and will help you improve your power, pace or output at that threshold level.
This type of work happens just above lactate threshold. It forces the body to process lactate through short, intense intervals closely stacked together, raising your lactate threshold over time and improving your ability to recover from hard efforts quickly.
This is best for events where multiple surges or maximal efforts are required in quick succession, like bike racing, short-course triathlon, Crossfit and run races shorter than 10K.
This is training done at an effort well beyond lactate threshold. Focus on anaerobic work to continue to force adaptation and fitness gains. These intervals can build sport-specific strength and are best done after six to eight weeks of general training.
Anaerobic training includes batches of intervals less than 1 minute in duration with 100 percent to 300 percent rest (think six repeats of 30 seconds on/30 seconds off, followed by 15 minutes of steady effort, repeated two to four times).
Caution: Anaerobic training too early in your season could lead to injury; too close to your competition, and it could impact your performance. Try this training on the bike first, as the limited range of motion lowers the chance of injury.