Lactate Threshold
Lactate threshold is reached when an individual's body can no longer clear lactate faster than its rate of production. This occurs due to an increase in exercise intensity. When muscles are working aerobically, they use oxygen to shuttle out carbons in the form of CO2. So a key factor looking to determine why one athlete has a higher lactate threshold than another is going to the athletes VO2 max. As we know in endurance sports it's all about efficiency. So the more efficient the athlete is at that given pace the less metabolic stress placed upon them. So it is reasonable to suggest the more efficient they are the higher their respective lactate threshold.
When training to increase an athlete's lactate threshold it is important to keep in mind the physiological occurrences happening as a result of different training types so that the training type chosen will elicit the desired physiological responses and adaptations. In this instance the athlete wants to be able to remain aerobic longer. This is achieved mainly by an increased ability to deliver oxygen to working skeletal muscle tissues. Consistent aerobic training is going to be responsible for the majority of the athletes increases in VO2 max. It has been shared by Kenney and colleges that “... an individual’s highest attainable VO2 max is usually achieved within 12-18 months of intense endurance training” (Kenney). With this in mind it is important to know the current state of the athlete and to not make blanket recommendations for training. Where this applies in this instance is if you have an endurance athlete who is still new to their sport and you've found they have a relatively low VO2 max it is reasonable to assume that focusing on protocols that improve general aerobic and endurance capacity instead of specifically LT will provide more use to their performance. One study showed that “High–aerobic intensity endurance interval training is significantly more effective than performing the same total work at either lactate threshold or at 70% HRmax, in improving VO2max” (Hoff). So When selecting a program to improve LT it could be advantageous to go past the threshold in an effort to increase VO2 max to its peak as quickly as possible.
As discussed early, the argument was made that efficiency is going to be another key component in an individual's ability to prevent the build up of lactate and the corresponding dissociating hydrogens that disrupt function through increasing pH. When having athletes perform HIIT workouts a lot of efficiency will be lost due to intensity, focus, biomechanics, as well as fiber type used. In order to make sure that the athletes maintain their desired efficiency it will be important to keep the majority of training at a much more conservative pace which will be defined by the given event that they compete in. This will allow for more reps at a slower pace giving the athlete more time to make sure they maintain the proper biomechanics. Also make sure the majority, but not all, of the athletes training is focused on building up the desired fiber type 1 muscle fibers. It is because all these factors play a role in decreasing the amount of work required that the lactate threshold would increase.
REFERANCES
Kenney, W. L., Wilmore, J. H., & Costill, D. L. (2020). Physiology of sport and exercise. Champaign, IL: Human Kinetics.
Faude, O., Kindermann, W., & Meyer, T. (2012, November 25). Lactate Threshold Concepts. Retrieved from https://link.springer.com/article/10.2165/00007256-200939060-00003