Key Points on lactate threshold:
- Like VO2 Max, lactate threshold is one of the most important physiological variables that best predicts success for endurance athletes.
- By strict definition, lactate threshold is the ability to sustain aerobic energy production at a high percentage of VO2 max without accumulating large amounts of lactic acid in the muscle and blood.
- It follows that a high lactate threshold can help you sustain a more intense pace for longer without fatiguing as quickly compared to someone with a lower lactate threshold.
- Several studies have shown that an athlete’s lactate threshold appears to be a better indicator of endurance performance than VO2 Max.
- There are two ways to accurately determine your lactate threshold, both of which must be done in a lab.
- If a lab is not available 80-90% of max heart rate correlates with lactate threshold pace for workouts.
- The best way to improve lactate threshold is though threshold workouts (tempo runs) performed near or slightly over race pace.
This article will discuss what lactate threshold is, how to test it, how to improve it, and sample workouts.
What is lactate threshold?
In endurance events, the best competitor among athletes with similar VO2 Max values is typically the individual who can sustain aerobic energy production at the highest percentage of his or her VO2 Max without accumulating large amounts of lactic acid in the muscle and blood.
Although numerous terms have been used to describe this phenomenon, lactate threshold is the one most commonly used.
Lactate threshold definition
Lactate threshold is the speed of movement or percentage of VO2 Max at which a specific blood lactate concentration is observed or the point at which blood lactate concentration begins to increase above resting levels.
Several studies have shown that an athlete’s lactate threshold appears to be a better indicator of his or her aerobic endurance performance that VO2 Max.
What is lactate threshold heart rate
In most endurance athletes lactate threshold occurs at 78-85% of maximum heart rate, with values of 88-90% maximum heart rate seen in elite endurance athletes.
What is clear from the information above is that endurance athletes must improve their lactate threshold if they want to become faster, more competitive, or develop a greater aerobic capacity.
This requires the endurance athlete to conduct some training at elevated levels of blood and muscle lactate to maximize training improvements.
Although much of the research examining the role of lactate threshold in predicting endurance performance has centered around distance running, the same principles apply to predicting performance in endurance cycling, swimming, and cross-country skiing.
How to calculate lactate threshold
The only accurate way of getting your lactate threshold reading is to go to a lab and be tested. If you don’t have access to a lab a less accurate field test can be conducted
Direct Testing of Lactate Threshold
This test protocol to determine lactate threshold:
- Begin with a 2-5 minute warm-up at a low work rate followed by a stepwise increase in power output/intensity every 1-3 minutes.
- To determine the blood concentration of lactate, blood samples are collected at each work rate from a catheter placed in an artery or vein in the subject’s arm or from a small puncture wound of the fingertip….sounds fun so far..amiright?
- After the test, blood samples are analyzed for lactate, and the concentration at each exercise stage is then graphed against the oxygen consumption at the time the sample is removed.
- From the graph, researchers can determine the lactate “breakpoint” (threshold) by using a ruler and drawing a straight line through the lactate concentrations at the first several work rates.
- The last point on the line is considered the lactate threshold. Your heart rate at this point should also be noted and recorded for training purposes. See the chart below as an example:
Lactate threshold chart
Field test for runners to find lactate threshold
The time-trial method of determining lactate threshold pace and heart rate can be done on a treadmill set at a 1 percent grade, on a running track, or on any other flat, smooth surface that’s conducive to fast running.
It also requires some means of measuring the time elapsed and distance covered as well as heart rate. Be sure to conduct this test on a day when you are not fatigued from recent hard training.
- Begin with several minutes of easy jogging to warm up.
- When you’re ready, start tracking time, distance, and pace on your treadmill or watch and run for 30 minutes at the fastest pace you can sustain for that amount of time.
- Be careful to avoid the common mistake of starting too fast and then slowing down toward the end of the time trial due to fatigue, which will produce an inaccurate result.
- When you get to 10 minutes, note your heart rate.
- At 30 minutes, stop and note your heart rate again.
- Calculate the sum of your heart rate at 10 minutes and your heart rate at 30 minutes and divide by two. That’s your LT heart rate.
- Your LT pace is your average pace for the entire 30-minute effort, assuming your pace was fairly steady.
A 2005 study by scientists at East Carolina University found that this method of determining LT heart rate and pace is very accurate. Its downside is that it’s hard—equivalent to running a half-hour race.
Time Trial Method For Cyclists
- Find a flat or slightly uphill stretch of road (avoid traffic lights, undulations or rolling hills).
- Warm-up for at least 10-15 minutes.
- Ride a thirty-minute time trial and give it your best. You should finish with nothing left.
- If using a HR monitor or power meter, record the last twenty minutes of your ride.
- Your average heart rate or wattage over this period is your estimated lactate threshold.
How to increase lactate threshold
Now that we know what lactate threshold is and how to test it; what is the best way to improve it?
The short answer is through pace/tempo training one to two times a week.
Workouts to improve lactate threshold pace
Pace/tempo training uses an intensity at or slightly higher than race competition intensity.
This intensity corresponds to the lactate threshold; therefore, this type of training is often called threshold training. There are two ways to conduct pace/tempo training: steady and intermittent.
Steady State Runs
Steady pace/tempo training is continuous training conducted at an intensity equal to lactate threshold for durations of ~20-30 minutes.
- The purpose of this pace/tempo training is to stress the endurance athlete at a specific intensity and improve energy production from both aerobic and anaerobic metabolism.
Intermittent Tempo Training
Intermittent pace/tempo training is done at the same intensity as a steady-state workout, but the training session consists of a series of shorter intervals with brief recovery periods between work intervals.
- During pace/tempo training, it is important to avoid exercising at a higher intensity than the prescribed pace. If the workout seems relatively easy, it is better to increase the distance than to increase the intensity.
The primary objective of pace/tempo training is to increase lactate threshold while also developing a sense of race pace and enhance the body’s ability to sustain endurance exercise at that pace.
Example Lactate Threshold Workout For Runners:
- Warm-up with an easy 5-10 minute jog.
- Next, slowly increase the pace to an intensity that is equal to 70-75% maximum heart rate.
- Next, perform 20-30 minutes at lactate threshold (80-90% maximum heart rate or heart rate determined from lab tests).
- Cool down with a 5-10 minute easy jog.
Example Lactate Threshold Workout For Cyclists:
Nothing Fancy here but here are some options that will get the job done:
- Example Lactate Threshold Training Session 1: 30 mins at an intensity sustainable for 1 hour.
- Example Lactate Threshold Training Session 2: 2 x 20 mins at an intensity sustainable for 1 hour separated by five mins active recovery.
- Example Lactate Threshold Training Session 3: 3 x 10 mins at an intensity sustainable for 30 mins, separated by 2-3 mins active recoveries.
- Example Lactate Threshold Training Session 4: 6 x 5 mins at an intensity sustainable for 30 mins, separated by 60-second active recoveries.
Take-home points on Lactate Threshold
- As with VO2 Max, improving lactate threshold should be a top priority of every endurance athlete from beginner to pro.
- What’s more, it may be a better predictor of success as an endurance athlete compared to VO2 max.
- An increased lactate threshold can help you maintain a quicker pace for longer and simulates race pace efforts.
- First and foremost, establish your lactate threshold through lab or field testing and retest every 4-6 weeks to measure improvements.
- Pace/tempo training should be performed 1-2 times a week after sufficient base training and can consist of steady or intermittent work intervals.