Serious Cycling: How to determine your lactate threshold

By Edmund R. Burke, Ph.D. 4/9/2002

The most obvious way to improve cycling technique is to ride, ride, and ride.

But if riding is the first step toward getting better cycling performance, then having a targeted training program is the second.

In the new edition of my book, Serious Cycling, I take the latest scientific information on cycling and digest that knowledge into easy-to understand, practical applications readers can put to use.

Serious Cycling bridges the gap between cutting-edge cycling science and winning cycling performance. This second edition has been updated and expanded to reflect the latest developments in research and technology. It contains new sections on power training and nutritional supplementation, as well as racing strategies from some of the world's leading riders.

The updated information will give cyclists the foundation they need to build endurance, increase lactate threshold, and enhance cycling strength and power.

I am often asked for information on how to determine one's lactate threshold without undergoing a laboratory test. Here is an excerpt from my book giving examples of field tests for determining your lactate threshold:

Lactate threshold field tests

Not many of us are able to be tested in laboratories and have our lactate thresholds determined by lactic acid measurements in relation to our intensity of effort. Here is a test that you can use on the road to get a fair estimate of your lactate threshold based on heart rate and power output.

Rob Sleamaker, author of Serious Training for Serious Athletes, has developed a field test that predicts your lactate threshold using a time trial. You will need a heart rate monitor, a stopwatch, and a record sheet to record date, distance, time, and your average heart rate. Be sure to warm up properly before the test.

Start the stopwatch, or use a cyclocomputer with a stopwatch mode, as you begin the test. Perform a 10-mile time trial or long, moderately steep climb at the fastest pace you can sustain and at a steady effort with no loss of speed. Your heart rate should stabilize after about five minutes. Record your finishing time. Assume that the average heart rate you achieved and sustained is your lactate threshold. Make sure you complete a cool-down after this hard effort.

Complete this test every four to six weeks during the year. You can use this test in place of a scheduled interval, hill, or race-pace workout. Use the heart rate and pace-per-mile results to help you plan your workouts for the coming weeks.

As you become more fit, you will reach the point at which lactic acid accumulation becomes delayed or shifts to the right and your lactate threshold coincides with a harder physical effort. Your lactate threshold will improve as your season progresses. Most elite athletes reach peaks in lactate threshold at about 85 to 90 percent of V02 max.

The heart rate or power you can maintain at this pace is indicative of your lactate threshold. Once again, it is important to consider environmental conditions because oxygen use, the level of lactic acid in the blood, and heart rate responses are markedly affected by wind and temperature.

An experienced cyclist learns to monitor lactate threshold by listening to specific physiological and psychological cues other than heart rate. Lance Armstrong describes his feelings this way: "You are usually at your lactate threshold heart rate when you are breathing hard and it is difficult to carry on a conversation with the other cyclists. In addition to heart rate and respiratory intensity, I try to monitor the feeling in my leg muscles and overall amount of effort."

Every year more cyclists use wireless heart rate monitors and power meters in conjunction with subjective measures to determine proper training intensity. A heart rate monitor and a power meter help you accurately determine your heart rate while you are riding.

Target training in new edition of Serious Cycling

With the second edition of Serious Cycling, competitive cyclists, cycling coaches, avid club members, and weekend century riders will have the means and the know-how to develop their programs and reach their full potential.

For more information on lactate threshold testing and training and how to obtain the book, visit