Workout Of The Week: Threshold, Long, Threshold (TLT)

Incorporate this threshold set into your long runs during marathon training.

The coach: Magdalena Lewy Boulet

The athlete: Clara Peterson, 16th at the 2012 U.S. Olympic Marathon Trials

When they did it: Peterson, who was a standout cross-country and track runner at Duke University, completed this workout as she was preparing for the California International Marathon in 2014. She ran this TLT workout six weeks before the race and ended up placing second in 2:35:35.

Why they did it: “I occasionally replace an easy long run with TLT to satisfy two workouts in one session [a long run and a threshold-paced run],” Lewy Boulet said. “This is a demanding session, but with great benefits. The inclusion of threshold running in the middle of 20-mile runs forces the running muscles to use up glycogen stores more rapidly than they would when running easy 20 miles.”

Lewy Boulet points out that you have the opportunity to practice fueling in this workout. Running at threshold pace after already completing 18 miles of running will make the marathon pace feel much more manageable on race day. Peterson also gained mental confidence by completing this session.

How they did it: Peterson started out with a 2-mile warmup. She then did 3 x 2 miles at threshold pace with 2 minutes of rest between each 2-mile repetition. She next ran 8 miles easy and then completed 2 miles at threshold pace. Peterson finished the workout with a 2-mile cooldown for a total of 20 miles. “Threshold ‘cruise intervals’ need to be run at proper intensity,” Lewy Boulet said. “They are meant to be comfortably hard, or about 83 percent of your VO2 max.”

How you can apply the workout: Admittedly, this is a hard workout. Lewy Boulet suggests instead of trying to keep track of miles, age group runners should focus on time. For example, marathoners should run 20 minutes easy for a warm-up and then run 3 x 15 minutes at your tempo pace (15 seconds faster per mile than your goal marathon pace) with 3 minutes rest between repeats. Then run 60 minutes easy and follow that with a final set of 15 minutes at tempo pace.

Conclude the workout with 20 minutes of easy running.

“This will provide you two hours and 40 minutes of quality running and prepare you well physically and mental for marathon race day,” Lewy Boulet said.