What is Lactate Threshold & Why Do Runners Need To Know This?

What is Lactate Threshold?

The lactate threshold is the exercise intensity at which lactate(Lactic Acid) begins to accumulate in the blood faster than it can be removed. This marker is significant because it can indicate a runner's endurance capabilities and potential for improvement.

Lactate itself is a byproduct of anaerobic metabolism, which occurs when the body needs energy quickly and cannot rely solely on oxygen for energy production. As you increase your pace, your muscles produce more lactate until it reaches a point where the body can't clear it efficiently. This is where the lactate threshold lies.

What is VO2Max?

VO2Max is the maxium amount of oxygen your body can consume during vigorous exercise. This is a great indicator of your cardiovascular fitness & aerobic endurance.

What is the Differnce Between LT1 & LT2?

LT1 is an aerobic threshold where lactate is being produced faster than the body can clear it. With the correct fueling you can hold pace for well over 45 mins before you notice a significant drop off. I'll use myself as an example. A Tempo Run for me would be 12KM @ 4:35 min/km which would be LT1. I find this pace is manageable for an hour.

LT2 is an anaerboic threshold where the body can no longer effectively remove lactate. This is an intensity that won't last very long, you may even find it hard to string a sentence together. For example for me, this could be 1km @ 3:40 min/km, after a few of these reps performance will begin to drop off as lactic acid will begin to slow me down.

The Importance of Lactate Threshold in Running

Understanding and training at the lactate threshold can help runners improve their endurance and speed. When you train around this threshold, your body becomes more efficient at clearing lactate, allowing you to sustain higher intensities for longer periods. This adaptation can lead to better race times and improved overall performance.

Moreover, focusing on lactate threshold training can reduce the risk of overtraining and injury. By training smartly, runners can ensure they are working within their optimal zones, promoting better recovery and minimizing fatigue.

How to Determine Your Lactate Threshold

There are several methods to determine your lactate threshold, ranging from lab tests to field assessments. Lab tests are the most accurate as they involve blood sampling during exercise to measure lactate concentrations. However, these tests can be costly and not always accessible for all runners.

Field tests, on the other hand, offer a practical alternative. One popular method is the 30-minute time trial. Run at a pace you can maintain for 30 minutes without slowing down, and record your heart rate during the last 20 minutes. The average heart rate represents an estimate of your lactate threshold.

Training to Improve Your Lactate Threshold

Once you've identified your lactate threshold, incorporating specific workouts into your training regimen can help improve it. Common workouts include tempo runs, interval training, and fartlek sessions. Tempo runs involve running at or slightly below your threshold pace for sustained periods, typically 20 to 40 minutes.

• Tempo Runs: Run at a comfortably hard pace for 20-40 minutes.
• Interval Training: Perform short bursts of speed followed by rest periods.
• Fartlek Sessions: Incorporate spontaneous bursts of speed within a regular run.

These workouts help increase the threshold by enhancing your body's ability to clear lactate and use it as a fuel source more effectively.

Monitoring Progress and Adjusting Training & Why Do Runners Need to Know This?

Training at the correct intensities is key to improving as a runner, put it like this: If you drive a car at full speed all the time you'll run out of fuel pretty quickly & you may even crash! The same principles our apply to bodies & how hard we can train.

Regularly monitoring your progress is essential if you're interested benefiting from your training efforts. Use tools like heart rate monitors or GPS watches to track changes in pace and heart rate at your perceived lactate threshold.

If you notice improvements, such as being able to maintain a faster pace with the same level of perceived exertion, it's a sign that your lactate threshold is increasing. Adjust your training intensities accordingly to continue challenging your body and promoting further adaptations.