Lactic Acidosis and Exercise: What You Need to Know

Muscle ache, burning, rapid breathing, nausea, stomach pain: If you've experienced the unpleasant feeling of lactic acidosis, you likely remember it.

It's temporary. It happens when too much acid builds up in your bloodstream. The most common reason it happens is intense exercise.


The symptoms include a burning feeling in your muscles, cramps, nausea, weakness, and feeling exhausted. It's your body's way to tell you to stop what you're doing

The symptoms happen in the moment. The soreness you sometimes feel in your muscles a day or two after an intense workout isn't from lactic acidosis. It's your muscles recovering from the workout you gave them.


Intense Exercise. When you exercise, your body uses oxygen to break down glucose for energy. During intense exercise, there may not be enough oxygen available to complete the process, so a substance called lactate is made. Your body can convert this lactate to energy without using oxygen. But this lactate or lactic acid can build up in your bloodstream faster than you can burn it off. The point when lactic acid starts to build up is called the "lactate threshold."

Some medical conditions can also bring on lactic acidosis, including:

Some drugs, including metformin, a drug used to treat diabetes, and all nucleoside reverse transcriptase inhibitor (NRTI) drugs used to treat HIV/AIDS can cause lactic acidosis. If you are on any of these medications and have any symptoms of lactic acidosis, get medical help immediately.

Preventing Lactic Acidosis

Begin any exercise routine gradually. Pace yourself. Don't go from being a couch potato to trying to run a marathon in a week. Start with an aerobic exercise like running or fast walking. You can build up your pace and distance slowly. Increase the amount of exercise each week so your body builds up a tolerance. This will increase your "lactate threshold," making it less likely you'll get lactic acidosis.

Make sure you drink lots of water. It helps get rid of any excess acid. Eat a balanced diet which includes lots of fruits, vegetables, whole grains, and lean meats. Get plenty of sleep at night and give yourself time to recover between bouts of exercise. How long that is depends on how you feel.

If your lactic acidosis is caused by a disease or medication, talk to your doctor. You may be able to make changes that will help you avoid the problem. And talk to your doctor before starting a new exercise routine.


What You Need to Know

If you start to feel the symptoms of lactic acidosis while exercising, begin warming down right away.

After you warm down, rest before exercising again, and make sure you get enough water.

Remember to listen to your body. If you feel burning and other symptoms of lactic acidosis while exercising, this is your body's way of saying stop. If your symptoms don't go away once you have stopped your workout, get medical help right away.

WebMD Medical Reference Reviewed by Melinda Ratini, DO, MS on September 16, 2014



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