Lactate and Glycogen Testing.

I do lactate testing on athletes. You can read more below. 

Some points on Lactate Testing.

1. Lactate Testing. You will have seen zones come up on your training watch. Heart rate zones are typically split into 5 sections – Zones 1 to 5. The zones are linked to your heart rate. Sports scientists began to realize a while back that the 5 zones have to do with a number of factors, the most important being your body’s ability to deal with lactate. Lactate is a byproduct of what happens as you use up fuel when exercising. Without getting too technical, as your body burns glycogen it produces lactate. This is known as the glycolytic energy system. It looks something like this – (hint: don’t worry if the graphic below doesn’t make sense. It is really complex and not essential for understanding the gist of this article)
2. At higher efforts your body puts out high levels of lactate that it cannot repurpose at the same rate as it is created. That together with a jump in hydrogen ions (H+) will cause that familiar burn in your muscles. The jump in hydrogen ions takes place both in the muscles and the blood stream and this gets recorded in your brain. Prof Tim Noakes’ so called “Central Governor” in your brain kicks in and in an attempt to protect you begins to slow the nerve communication pathways to your legs.  You know the feeling well, you push hard up a hill on a run or cycle and suddenly your legs begin to burn and with that you make a decision (or more accurately, the decision is made for you) to back off a bit till your legs feel better. That’s the point when your lactate levels begin to sky rocket. Have a look at the Zone chart below.
   Notice how lactate rises gradually through zones 1 and 2 (It’s really manageable at this point) It then goes up more rapidly in zone 3 (You can typically race at the upper levels of zone 3 for an hour). Lactate really begins to go up in zones 4 and 5. Zones 4 and 5 are zones you experience when running hard, lets say at a track session. You end your 400 meters breathing hard with your hands on your knees.I will be looking out for three things.
   1. The first inflection point indicating that your body will no longer be able to repurpose lactate.
   2. Your heart rate/breathing feel that should take place during moderately hard runs, intervals etc.
   3. Your heart rate/breathing feel that should take place during more difficult intervals.There is a direct correlation between heart rate and lactate turning points. The link thus enables the athlete to accurately control effort levels via their heart rate which is obviously easier to monitor during training/race conditions than constant lactate testing.Interesting facts about lactate.- Lactate is essential for brain function and is the main fuel that your neurons use.

   – Blood lactate levels are 2-3 x higher in people with type 2 diabetes.

   – Cancer cells have a disruptive metabolism and use too much glucose. This is known as the Warburg effect. They therefore produce high levels of lactate which possibly contributes to tumor growth.

   You can read more about Lactate here. 

   2. Glycogen testing.
   The plan is to test glycogen at the same time and thus more accurately determine if the athlete is consuming enough fuel during an event. These figures will vary tremendously with each athlete due to mitochondrial efficiency. The longer and more consistently an athlete has been training the more effective their mitochondria become. (The difference between a top professional cyclist and an athlete with type two diabetes can be as much as five fold in performance levels derived from Mitochondrial efficiency).

   Prolonged lower zone running will mean that your body has learnt to better use fat as a fuel. There is simply no short cut to get to this point as we are typically looking at 3 years of consistent low HR training to become a fat burning machine. You can read more about fat burning HERE. 
   Fat burning athletes will therefore tap into glycogen stores more slowly and that will show up on this kind of testing.

    

   

   There is a link between lactate and glucose. Lactate is primarily produced in fast twitch muscle fibers which use glucose for energy, and cleared mainly by slow twitch muscle fibers. One of the reasons that I as a coach push low HR training is that we improve an athlete’s lactate clearance capacity. This is done primarily by increasing the amount of mitochondria in the muscles.

   Have you ever run a marathon and run out of steam? It has a number of different names, they include: bonking, hitting the wall, carrying a bear on your back etc. It’s that moment when your glycogen reserves run dry and it’s an awful experience. I know, I’ve been there. To make matters worse, fat, the ultimate endurance fuel, is burnt/oxidized on a carb flame and so your body loses its ability to efficiently burn fat. You are left trying out a mix of walking and jogging while seriously questioning your life choices. That is exactly what why we are introducing glycogen testing as part of the coaching package.

   By testing we will get an indication of the following:
   a. How your fueling strategy is going during your run.
   b. How efficient you are at burning fat. An efficient fat burner will be taking in less carbs (CHO) and will maintain similar glucose levels to an inefficient fat burner needing to take on more CHO.

   The results are then collated and feedback given later to the athlete. Runners need to put aside an hour so that we can get enough running in at various intensities.

   Bike testing will be done at my office at Moove Gym. Bring your smart trainer and bike. It’s best for us to use a step up program such as found on the Zwift app.

   Click HERE for pricing.

   Yours in sport.

   Mike Roscoe.
   Coach/Kinesiologist.