Lactate: Your Best Friend or Worst Enemy?


By Chris Carmichael,
CTS Founder and Chief Endurance Officer

Several years ago I became more interested in lactate, particularly because both research and experience were suggesting that coaches and sports scientists had been wrong about the stuff. Recent years have seen a renaissance for lactate, but out on the road and in the blogosphere I still hear misinformed people railing against the evils of lactate. As an endurance athlete, it’s important that you change your mindset and realize that lactate is your friend, not your foe!

How Lactate Got a Bad Name

There are a lot of biochemical reactions involved in turning a turkey sandwich into energy your muscle cells can use, and there are several pathways for those reactions, depending on your acute demand for energy. I’m not a biochemist, so please excuse the simplification that follows, but a few decades ago, scientists formed a hypothesis that skeletal muscles fatigued because of “lactic acidosis”, or a drop in intracellular pH due to the accumulation of lactic acid. More specifically, the culprit was the hydrogen (H+) ion that dissociated from the lactic acid, leaving a hydrogen ion and a lactate salt. The trouble is that while acidosis is a real consequence of intense exercise, it may not be the ions coming from lactate that are causing it. Nevertheless, “lactic acid” caught on, especially with the public, and has become synonymous with that burning sensation athletes feel when they go hard.

Lactate’s Redemption

One of the things we’ve known for a long time in sport is that the best endurance athletes produce a lot of lactate when they are really going hard. When you run a lactate threshold test on a moderately fit cyclist and compare it to an elite cyclist, not only is the elite cyclist’s power at lactate threshold higher, but the elite athlete’s peak blood lactate levels are also higher. But what’s also interesting is that the elite athletes’ blood lactate levels often start out lower at the beginning of the test, meaning their range during the test is much greater (<1mmol to 20mmol compared to say 2.5mmol to 14mmol for the amateur).

When the prevailing thought was that lactic acidosis caused fatigue, we figured that elite athletes had increased ability to remove and buffer the positive ions. In essence, they had a better “defense” against the acidic environment. But when researchers like David Brooks and Robert Robergs helped us see lactate as a fuel rather than an unwanted byproduct, and recognize that acidosis might be caused by positive ions coming from other reactions, it opened up the possibility that athletic performance could be improved by producing MORE lactate and encouraging the use of more lactate for energy!

So, now that we’re all up to speed, here’s how I currently believe endurance athletes should think about lactate:

Free Cycling Training Assessment Quiz

Take our free 2-minute quiz to discover how effective your training is and get recommendations for how you can improve.

  • Lactate is always present: As you read this article you’re producing lactate and using lactate for fuel. Cardiac muscle prefers lactate as its fuel source, and it’s a more significant fuel for skeletal muscle – at all intensity levels – than most people realize.
  • Lactate is partially-burned fuel: When your energy demands are lower, you’re able to wring the most energy out of a mixture of fuels, but energy production is slower. When you need energy faster, glycolysis is a metabolic shortcut that’s fast but yields less energy per molecule. But the lactate that’s also produced represents energy you can also burn.
  • Intense training increases the amount of lactate your produce and how much you can use: Long easy miles have their place in training, but they don’t increase your ability to produce and use lactate for fuel. That comes from short (30sec-4min) intervals at maximum intensity.
  • Lactate moves around: Lactate can be produced in one muscle and processed in another. That’s one of the reasons it’s important to keep your legs moving during recovery periods and descents. The small muscle contractions facilitate circulation and you can bring fresh fuel to working muscles and distribute lactate throughout your body to be used for energy.

When you go out to become a faster cyclist, a stronger climber, or a better finisher, you don’t want to minimize the impact of lactate; you want to take full advantage of it! That means tailoring workouts to not only generate a ton of lactate, but also give you the opportunity to continue riding at a high-intensity level while processing that lactate for fuel. Here’s a great workout CTS Coaches use for this exact purpose with the athletes we coach:

Threshold Ladders

Each of these 8-minute intervals is actually made up of 3 segments. You start out with 1minute at maximum intensity (10/10), and then drop down to your time trial or max sustainable climbing intensity (at or above lactate threshold, 8-9/10) for 3 minutes. At the end of that segment you drop down again, this time to your lactate threshold intensity or slightly below it (7-8/10). If you’re familiar with the CTS Field Test and CTS Power Zones, each interval consists of 1min at PowerInterval power (max), 3minutes at ClimbingRepeat power (95-100% of field test power), and 4minutes at SteadyState power (86-90% of field test power). Take 4minutes easy spinning recovery between each 8-minute ThresholdLadder interval. Intermediate riders should do 3-4 intervals and advanced riders should aim for 4-6 intervals.

FREE Mini-Course: Learn How to Maximize Your Limited Training Time

Learn step-by-step how to overcome limited training time and get faster. Walk away with a personalized plan to increase your performance.

This field is for validation purposes and should be left unchanged.

Comments 11

  1. Hi, Phil.Thank you for the compliment! I rlaley appreciate you taking the time to post it.There has been little research examining the effect of spreading a particular workload over more or fewer days. I recall one that examined the effect of a weekend warrior type schedule, where the bulk of the weekly training was done during the weekend. If my memory is correct that study didn’t specifically examine differences in performance, it was focused on whether weekend trainees were injured more frequently (they aren’t).My personal opinion is that it isn’t so much the number of days that a particular volume is spread over that is the primary factor in the results enjoyed; I think it is the specificity of the workouts that determine the results obtained. Running a consistent 4 miles a day, 6 days per week would train many fewer muscle fibers and be less specfic for a half-marathon than running 3 days per week with 1 long, easy run, 1 medium, moderate run, and 1 short, fast run each week that totaled the same 24 mile distance. Also, 6 days of 4 miles per day would likely overtrain the primary muscle fibers used for running 4 miles while simultaneously undertraining all the other fibers in the working muscles.I think each individual muscle fiber has to be trained and then allowed to rest and recover. While one set of fibers is resting another set can be trained.

  2. Heck and other German pioneer scientists argued that 4mmol lactate marks the Onset of Blood Lactate Accumulation (OBLA) in the vast majority of athletes undergoing ramp or incremental protocol tests or during field tests.
    Indeed, if you chose 4mmol lactate as the OBLA, you’d be right 80% of the time. However, individual athlete lactate profiles vary. We’ve measured MLSS lactates most frequently around the 4-5mmol range, but a few have been as high as 6-9 range. Stegmann and Kinderman (more Germans!) developed and published the “Individual Anaerobic Threshold”, recognizing this fact. The classic determination of MLSS requires several “runs”, each at a constant speed/intensity, each lasting at least 20 minutes, each run at a progressively greater speed/intensity, until the highest constant effort is found which does NOT demonstrate up-trending lactate series during the run. There is GREAT utility in knowing the individual MLSS, for purposes of predicting race performances, for setting up intensities for training, for intercepting overtraining, for measuring favorable adaptation to training.

    I also cannot over emphasize that the “lag time” between the measured blood lactate, and the stage of the test responsible for that blood value, can be up to 2-3 minutes apart! Yes, it depends on the protocol. Real field and race experience assignments (FTP, run test) may conflict with lab determinations of lactate threshold or MLSS if this delay is ignored. An error of 20-40 watts or 20-30 sec/mile pace can “break” an athlete on a distance course, when attempting maximum sustainable intensity. The error can also make the difference between finishing a set of intervals, or not.

    We generally favor combined breath gas and blood lactate analyses. The GET or gas exchange threshold closely corresponds to the MLSS. Additional information and metrics are gained.
    Precision Multisport Testing, LLC

  3. Pingback: The Chopped Diet Peek #16 Chop your HungerThe Kitchen Chopper

  4. I’m interested in your perspective on the use of supplements like Beta Alanine with regards to Lactic Acid / Lactate. Good, bad or no difference relative to your body producing lactate for use as fuel.

  5. Why does the interval have to be sport specific? If the goal is to create loads of lactate (lactate creation efforts – similar in 400m running) then just do 1min efforts with 4mins steady between. This is not race specific but if you truly go max on the one minute effort then you will have to lay on the floor to recover.
    Would you expect a kilo rider to finish his kilo and then ride another 3 mins after at VO2max? Would that even be possible?

    1. I take your point but these training workouts are most suitable for endurance athletes and not for kilo riders or 400m runners. For myself, I would do the 1 minute effort at about 500 watts on the bike or running a 400m in about 60 seconds.

  6. I have found with athletes where a lactate trace may produce 8-9 mmol/l at said power and then the client goes out and does around this power for a 50mile ITT, which I would have said was impossible (i.e. well above OBLA).
    It would be interesting to see if the MLSS is still of practical use and if long ITT’s such as these are still ridden at MLSS intensity or if blood lactate continually increases. I have completely fallen out with incremental lactate traces – I dont believe the LT exists in a standard incremental protocol – it is simply an exponential rise from baseline. The only important points of use are the MLSS (can be found from the palmer protocol in 1 visit) and LT1 (useful to demarcate the upper boundary of intensity for LSD rides). I would be interested to hear any one else’s thoughts on this matter.

  7. Wouldn’t the 8 minute intervals at a regression teach the body and mind to give up and go slower ?? Meaning because you go down in effort towards end instead or progression ??
    Thanks chip

    1. Post

      Good question, but that’s not how we’ve experienced or observed the workout to impact athlete performance. Many times a maximal effort like a PowerInterval is done for 1-3 minutes at as high a power output as the athlete can sustain for that duration. This generates a lot of lactate, but is followed by easy recovery before another interval. For those subsequent intervals the athlete starts with elevated lactate levels because it’s not completely processed back into aerobic metabolism in the short recovery period. In this workout progression the key is for the initial effort to be truly maximal; athletes can’t hold back and pace the effort based on the fact there is LT intensity work included. The goal is to complete a solid amount of LT work with a high amount of lactate already present. This is a sport-specific application for cyclists, cyclocross racers, MTB racers, triathletes, and runners because there are times when maximal surges are not followed by easy recovery but are instead followed by prolonged efforts at maximum sustainable power/pace. – Jim Rutberg, CTS Pro Coach

      1. It sounds similar in concept to a drop set that a weight lifter would do. Sounds great, I look forward to trying it. Especially as.a former strength athlete.

Leave a Reply

Your email address will not be published. Required fields are marked *