Blaming Lactic Acid for Your Soreness?

Had the opportunity and privilege to attend IDEA World 2017 in Las Vegas (July 20th-22nd), and took CEUs towards my NASM-CPT re-certification in a variety of topics with an emphasis on program design: Learned about the newest (less than 7 years old) research in HIIT (High Intensity Interval Training), the strength benefits of eccentric loading, the significance of establishing stiffness in dynamic warmups, and why loaded rotational movements are really the true "functional" fitness. 

More to come on these topics - But I'll leave my favorite fun fact for now:

Quick recap on cellular metabolism physiology: 
Everything we do requires energy, which we get from the splitting of a compound called ATP (adenosine triphosphate), which is three phosphate groups attached to a Base-A nucleic acid (adenine) and a ribose (sugar). Phosphate groups are negatively charged molecules, so when they break, they release energy! Once it splits via hydrolysis (water), it breaks into ADP (adenosine diphosphate) and a single phosphate group. The water molecule adds a hydroxyl group (-OH) to the phosphate group, leaving one lone hydrogen ion (H+).

Now, getting to the fun part:
In moderate exercise, these lone protons are redistributed in aerobic metabolism; however, in vigorous or high-intensity exercise, the body shifts into anaerobic metabolism, with a significant increase in ATP hydrolysis occurring, resulting in a build up of H+, and creating acidosis (a highly acidic environment in the cell). Muscle cells don't like this and we feel the "burn"!  

Okay, a bit more physiology:
This process occurs via glycolysis, which creates a byproduct of 2 pyruvate molecules, and of course, the surplus of hydrogen ions. As a method for neutralizing the cell's pH, each pyruvate will bind with 2 of the hydrogen ions producing our dear friend lactate. 

Friend? Lactate is a toxin! Right?!  
Lactate, often confused with lactic acid (as the thing we wrongly blame when we feel sore), is not the true reason we experience acidosis. [Lactic acid isn't even the root of soreness; rather, DOMS, delayed-onset muscle soreness, via micro-injuries and inflammation is the true cause, but that's another discussion]. Lactate is really a temporary neutralizer (a buffer) that is a product of glycolysis, not the cause of acidosis. It's helping to make the cell's environment more favorable, and for this reason, it's a friendly compound.
If you continue to push the body in vigorous activity while in anaerobic respiration, the lactate build-up will eventually inhibit the muscle, decreasing your performance. This is again a friendly behavior, as it protects the muscle from fatigue and possibly injury. 

So here's the big take home message:
ATP hydrolysis is the true cause of acidosis, and it's inevitable. We need it to survive! Asking how to avoid it all together isn't reasonable, so instead...

How can you reduce the amount of acidosis production while exercising so that your performance doesn't suffer?
1. Stay hydrated. Yes, water is what fuels the hydrolysis, but water is also what dilutes the lactate, keeping it from building up too high. If you are thirsty when you exercise, you are already dehydrated.
2. Warm-up and cool-down when exercising. The more you can prepare the  body for movement, the more likely the body can prepare for the proper cellular metabolism.
3. Breathe. The more/deeper/slower you breathe, the more oxygen your pulmonary system absorbs, and the more likely you can shift back into aerobic respiration. 
4. Keep at it. If you're exercising regularly (without changing your routine), you're likely finding that what once was a vigorous activity becomes moderate. The higher the intensity, the more carbohydrates (glucose) is required for fuel, and as discussed here, the more lactate byproduct. As your intensity catches up with you, fats provide an alternative fuel source, resulting in less lactate production; Additionally, training increases the tolerable threshold for lactate that your body can handle. Whereas before it took a selective amount of lactate to feel the burn after, say, 1 minute, training can boost the duration of time it would take to feel that same burning sensation from a now larger amount of lactate.
That said, to keep advancing in your training and to avoid plateaus from habituation, consider boosting your intensity again, and expect a bit of lactate. 

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Susie Lunardi
Conference Lecture & Discussion Source: Kravitz 2005  
(Other Sources: Allen 2004, Colberg 2010, Florida A&M)
Something off in my facts? Let me know - I'm all about finding the right information, not feeding the ego. Share your sources with me!