Triathlon: What is Threshold Training?

Want to race faster and longer with threshold training?

Triathlon training isn’t just about going long and slow or sprinting at top speed—it’s about mastering the in-between efforts, too. That’s where threshold training comes in.

Threshold training is the sweet spot between aerobic endurance and all-out effort. It’s where the body learns to sustain high-intensity work without fading, helping triathletes push harder, race stronger, and delay fatigue.

Training at this level boosts speed, builds endurance, and improves overall race performance.

Whether training for a sprint triathlon or an Ironman, threshold sessions are a game-changer for taking fitness to the next level.

What is Threshold Training?

Threshold training focuses on working just below or at lactate threshold—the intensity where the body starts producing more lactate than it can clear. At this effort, breathing is deep but controlled, muscles are working hard, and sustaining the pace feels challenging but doable.

It’s the point where the body learns to handle higher intensities without burning out. The more an athlete trains at threshold, the higher their sustainable race pace becomes.

Why Threshold Training is Important for Triathletes

Builds Race-Day Speed and Stamina

Threshold training allows triathletes to hold a faster pace for longer without feeling drained. This means stronger bike splits, faster run legs, and better overall race times.

Delays Fatigue

By increasing the body’s ability to process and clear lactate efficiently, threshold training helps athletes push harder without hitting the wall too soon.

Improves Pacing and Control

Triathletes who train at threshold effort develop a better sense of race pacing, making it easier to stay in control and avoid early burnout.

Increases Aerobic Power

Threshold sessions strengthen the heart, lungs, and muscles, improving overall endurance and making race pace feel easier over time.

How to Incorporate Threshold Training into a Triathlon Plan

Cycling Threshold Workout Example

🔹 Warm-up: 15 minutes easy spinning

🔹 Main Set:

• 3 x 10 minutes at a hard, controlled pace (just below max effort)

• 5-minute easy spin recovery between efforts

🔹 Cooldown: 10 minutes easy spinning

Running Threshold Workout Example

🔹 Warm-up: 10-15 minutes easy jogging

🔹 Main Set:

• 4 x 8 minutes at a steady, strong effort

• 3-minute jog recovery between efforts

🔹 Cooldown: 10 minutes easy running

Swimming Threshold Workout Example

🔹 Warm-up: 400m easy swim + drills

🔹 Main Set:

• 5 x 200m at a tough but steady pace

• 30 seconds rest between reps

🔹 Cooldown: 200m easy swim

Final Thoughts

Threshold training is a key ingredient in triathlon success, bridging the gap between endurance and speed. By consistently training at this effort level, triathletes can race harder, last longer, and perform stronger when it matters most.

Adding threshold workouts to a training plan helps increase sustainable speed, improve pacing, and build resilience against fatigue, making race day feel smoother and more controlled.

Consult a healthcare professional before starting any fitness plan to ensure it is safe and appropriate for your individual needs.