Training: Threshold Training for Improved Lactate Tolerance

Written by: Edmund R. Burke, Ph.D.

Many coaches and scientists consider one's lactate threshold to be a good indicator of an athlete's potential for endurance performance. Lactate threshold is defined as the point in which blood lactate begins to accumulate above moderate levels in one's blood during exercise of increasing intensity. As most of you know, during light to moderate activity, lactate stays slightly above resting level. But at some level of exercise intensity, blood lactate levels increase rapidly. This breakpoint in the curve represents the lactate threshold.

Even though many athletes use lactate threshold training in their programs, it is still a nebulous term. Ask any group of scientists and coaches to define the term and you are likely to get ten different answers. "The point that we are defining is a small range where an athlete can train and compete optimally," says J. T. Kearney, a sports physiologist at the Olympic Training Center, "and lactate threshold is a term used to define that range." Other terms such as anaerobic threshold or heart rate deflection point are often used in the literature to define the point Dr. Kearney is referring to.

For most fit athletes this will be between 80% and 90% of their max heart rate. When training in this zone, the primary benefit to you is an increase of the speed or effort that you can work at before you cross over into the pain of lactic acid accumulation. Provided you have the proper aerobic base built from primarily endurance work, this training could well provide the level of training that will take your racing results to the next level.

When you are exercising at this intensity you will experience heavy breathing, tired muscles and fatigue. And when you train at this effort , you will experience a training effect that will allow you to sustain more work at higher intensities at a lower heart rate.

The importance of training at lactate threshold is significant for several reasons. If everything else were equal, the higher your lactate threshold, the faster pace or speed that can be held over long distances or steep climbs or trying to break-a-way from other athletes in races. While success in competition is in part related to high maximal aerobic capacity and the ability to sprint at the end of the race, it also requires you to compete at a pace which is at a high percentage of your maximal capacity. Scientist often refer to this ability as meaning that an athlete can effectively use a high percentage of their maximal oxygen consumption for long periods of time while training or racing.

Training at the lactate threshold is used to shift the point at which lactate accumulates to the right, i.e., at a faster pace or higher percentage of max VO2. Everything else being equal, the higher the lactate threshold, the faster the pace that can be held over long distances.

Specific training programs in the Carmichael Training Systems will help you raise your threshold from 75-80% to the 85 to 90% level found in elite athletes. This means that you will be able to exercise at a pace closer to your maximum oxygen consumption. An example of this would mean that you will be able to raise your speed on a long steep climb on a mountain bike lets say 8 miles per hour to 10 miles. You will also be able to break-a-way with fitter cyclists, climb hills stronger and attack with more speed, but only after you have the proper base of endurance conditioning. If one does not have the proper base of aerobic conditioning these workouts will tear you down rather than build you up.

If you're not already not using lactate threshold training, try adding a little to your weekly program. Start off with one session per week, and gradually increase the intensity and length of these sessions (but not frequency- once a week is plenty) of your threshold workouts and continue your threshold training as you sharpen up for big races. Your race performances will improve, as your lactate threshold goes up.

Finally, you do not have to limit yourself to one or two of the above workouts, but feel free to even mix several of the above workouts listed in the side-bar to your heart's content. In fact, variety will help to make the intense efforts of threshold training a little more tolerable. Whatever you do, do it with commitment- intensity is the key to getting the most out of your threshold training sessions.

Threshold training is hard training and this form of training requires recovery, so be sure to spend a day of easy training after such workouts. Remember to it is wise to occasionally train easy so you can train hard.