Enter the maximum heart rate and the percentage of HRmax at the lactate threshold into the calculator to determine the lactate threshold, which is calculated by multiplying the maximum heart rate by the difference between 1 and the percentage of HRmax at the lactate threshold (expressed as a decimal).

## Lactate Threshold Formula

The following formula is used to calculate the lactate threshold (LT) using heart rate data:

LT = HRmax * (1 - (LTpercentage / 100))

Variables:

• LT is the lactate threshold
• HRmax is the maximum heart rate
• LTpercentage is the percentage of HRmax at the lactate threshold

To calculate the lactate threshold, multiply the maximum heart rate by the difference between 1 and the percentage of HRmax at the lactate threshold (expressed as a decimal).

## What is a Lactate Threshold?

The lactate threshold refers to the intensity of exercise at which lactate, a byproduct of anaerobic metabolism, begins to accumulate in the bloodstream at a faster rate than it can be removed. This threshold is significant because it is an indicator of fatigue during strenuous exercise. When the body is working within its lactate threshold, it is able to efficiently remove the lactate produced by the muscles and use it as a source of energy. However, when the intensity of exercise exceeds the lactate threshold, the body is unable to keep up with the removal of lactate, leading to its accumulation in the blood. This accumulation causes the pH of the blood to drop, leading to acidosis and subsequent muscle fatigue and decreased performance. The lactate threshold is, therefore, a critical factor in endurance sports, where sustaining a high intensity of exercise for a prolonged period is key to performance.

## How to Calculate Lactate Threshold?

The following steps outline how to calculate the Lactate Threshold:

1. First, determine the lactate levels (mmol/L) at different exercise intensities.
2. Next, plot a graph with exercise intensity on the x-axis and lactate levels on the y-axis.
3. Identify the point on the graph where lactate levels start to increase exponentially.
4. This point is known as the Lactate Threshold.
5. Finally, record the exercise intensity at the Lactate Threshold.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Lactate levels (mmol/L) at different exercise intensities:

Intensity 1: 2.5 mmol/L

Intensity 2: 3.2 mmol/L

Intensity 3: 4.1 mmol/L

Intensity 4: 5.5 mmol/L

Intensity 5: 7.8 mmol/L

Plot a graph with exercise intensity on the x-axis and lactate levels on the y-axis. Identify the point on the graph where lactate levels start to increase exponentially. Record the exercise intensity at the Lactate Threshold.