5.13.2007

Lactate Threshold Training

Introduction
One of the secrets to Lance Armstrong's incredible success was that his training regiment was built specifically around his lactate threshold. Chris Carmichael, Armstrong's coach, explains:

"Power isn't the issue. Anyone can produce 400 watts for a few seconds. However, most riders can't produce 400 watts for a very long time without going anaerobic and slowing abruptly. What's key is the ability to produce significant power while remaining under your lactate threshold (LT) and in control. All of Lance's training revolved around raising his power at LT. The secret is to do most of your hard training a little below, at or slightly above your lactate threshold."

To produce energy for movement, the muscles primarily use fat and carbohydrate for fuel. When carbohydrate - the sugar-based fuel source - breaks down (glycolysis), lactic acid is produced in the muscles. As it seeps out of the muscle cell and into the blood, hydrogen ions are released and the resulting salt is called "lactate." This is most commonly referred to as "lactic acid," which is a by-product of the lactic acid system resulting from the incomplete breakdown of glucose (sugar) in the production of energy. Your lactate threshold is the point during exhaustive exercise at which lactic acid is being produced at a faster rate than it can be removed from the bloodstream.

One of Lance Armstrong's training secrets was to invest a lot of time cycling right at this lactate threshold point. By doing so, he trained his muscles to maintain a high force load for a prolonged time. This improved his body's capacity to process lactate, conserve fuel sources and resist fatigue.

Calculating Your Lactate Threshold (LT)
Like calculating maximum heart rate (MHR) and VO2 Max, determining your lactate threshold can be done in a variety of ways, though some are more reliable than others, and is easy enough for you to do on your own during a workout. There are five primary ways to calculate your lactate threshold:
  1. Go to a sports science lab and have your lactate threshold tested there. This will likely be expensive, but it will yield the most accurate result.
  2. Purchase a self-test kit. These are easy to order online, but they are also expensive. If you're bent on getting a lactate measurement directly from your blood, this might be the best way to go.
  3. Determine the pace you could run at for one hour. This is a good way for you to come up with a very rough estimate of the speed at which you'll reach your lactate threshold.
  4. Calculate an estimate of your threshold using an online calculator. These are based on the results of a race, and though not as accurate as blood testing, they will give you a pretty good idea of where your threshold is.
  5. Ride or run your best 30-minute time and record your heart rate during the last 20 minutes. Your average heart rate during this time will closely match your heart rate at lactate threshold. This is one of the most useful estimates available since heart rate training is common, and heart rate monitors are reliable, easy to use and relatively inexpensive. Also, this speed correlates very closely with an effort level of 82% - 87% of maximum heart rate for beginners and about 87% - 92% of maximum heart rate for more experienced athletes.
Lactate Threshold Values
Because lactate threshold occurs sooner than VO2 max is reached, it is often measured as a percentage of VO2 max. Athletes and coaches measure the power output (usually in watts/kg) at their lactate threshold in order to design training programs.
  • The average person reaches their LT at 60% of their VO2 max.
  • Recreational athletes reaches their LT at 65% - 80% of their VO2 max.
  • Elite endurance athletes reach their LT at 85% - 95% of their VO2 max.
Increasing Lactate Threshold
Debate continues regarding the science of the lactate threshold, whether there is such a point and the value of trying to measure it at all. The good news for athletes is that although these numbers may or may not be proven, it has been shown that with training athletes are able to tolerate higher intensity exercise for longer periods of time. Here are two simple ways to help increase your LT:

Proper Training
LT training means increasing your exercise intensity so you train at or just above our LT heart rate. This training can be interval training or steady training.
  • Interval LT Training: Twice a week perform three to five 10-minute high effort intervals at 95-105 percent of your LT heart rate with three minutes of rest between intervals.
  • Continuous Training: Twice a week perform one 20-30 minute high intensity effort at 95-105 percent of your LT heart rate.
Proper Nutrition
To boost our LT during training and racing, you need to make sure you can exercise at high intensity without running out of glycogen stores. This requires careful nutritional meal planning both in the pre-exercise meal and post-exercise meal.

Summary
The breakdown of glucose or glycogen (carbohydrates - a sugar-based fuel) produces lactate and hydrogen ions. For each lactate molecule, one hydrogen ion is formed. It is the presence of hydrogen ions, not lactate, that makes the muscles acidic and results in the deep burning sensation and the hindrance of muscle function. Your lactate threshold is the point during exhaustive exercise at which lactic acid is being produced at a faster rate than it can be removed from the bloodstream. Training at the lactate threshold improves the body's capacity to process lactate, conserve fuel sources and resist fatigue. Bottom line: you can go harder, longer.

Sources
The Fun Times Guide, Jim P.,

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