Burn, Baby! Burn!: The Truth About Lactic Acid

It seems that almost every conversation about resistance training or anaerobic activity always centers on “The Burn”. I’m talking about that deep burning sensation in your muscles that feels hot or stingy when reaching muscle exhaustion during weight training or short burst energy activities like sprinting. What exactly causes that burning sensation and is it a sign that you’re exercising correctly?

Without getting too technical, that burning sensation is caused by a buildup of lactic acid. When we do exercise for short periods of time (up to 3 minutes), our bodies are in an anaerobic state. Anaerobic means “without oxygen” and means that when we need immediate energy, oxygen is not a readily available source of energy. So, our body relies on another form of quick release energy called glucose. When this happens, glucose is broken down into pyruvate and when we are in anaerobic activity, pyruvate is converted into lactate. When your body has high levels of lactate (lactic acid), there is also an increase in the acidity of the muscle cells themselves which creates that burning sensation. This is exactly why when you are truly in an aerobic state, you do not feel “The Burn”.

Although there are those that believe lactic acid is what causes us to have DOMS (Delayed Onset Muscle Soreness), it has never been proven that this is the case. Muscle soreness is caused by microscopic muscle fiber damage. When you have muscle fiber damage from exercise, your muscles become inflamed and swell which is what causes the soreness you feel from exercise during the next 2-3 days afterwards.

There you have it, the truth on lactic acid. It’s a perfectly natural part of exercise and is the direct result of spent energy during anaerobic activity. So, the next time you hear a conversation pairing that burning sensation with muscle soreness; you can step right in and tell the burning truth.

 

Burn Baby Burn; The Truth About Lactic Acid

It seems that almost every conversation about resistance training or anaerobic activity always centers on “The Burn”. I’m talking about that deep burning sensation in your muscles that feels hot or stingy when reaching muscle exhaustion during weight training or short burst energy activities like sprinting. What exactly causes that burning sensation and is it a sign that you’re exercising correctly?

Photograph courtesy of Shutterstock

Without getting too technical, that burning sensation is caused by a buildup of lactic acid. When we do exercise for short periods of time (up to 3 minutes), our bodies are in an anaerobic state. Anaerobic means “without oxygen” and means that when we need immediate energy, oxygen is not a readily available source of energy. So, our body relies on another form of quick release energy called glucose. When this happens, glucose is broken down into pyruvate and when we are in anaerobic activity, pyruvate is converted into lactate. When your body has high levels of lactate (lactic acid), there is also an increase in the acidity of the muscle cells themselves which creates that burning sensation. This is exactly why when you are truly in an aerobic state, you do not feel “The Burn”.

Although there are those that believe lactic acid is what causes us to have DOMS (Delayed Onset Muscle Soreness), it has never been proven that this is the case. Muscle soreness is caused by microscopic muscle fiber damage. When you have muscle fiber damage from exercise, your muscles become inflamed and swell which is what causes the soreness you feel from exercise during the next 2-3 days afterwards.

There you have it, the truth on lactic acid. It’s a perfectly natural part of exercise and is the direct result of spent energy during anaerobic activity. So, the next time you here a conversation pairing that burning sensation with muscle soreness; you can step right in and tell the burning truth.

To Succeed in Fitness, Just Follow Your Heart

Throughout our lives we have heard the phrase, “follow your heart.” It’s great advice for anyone and I truly believe you cannot go wrong by doing so. And, it just so happens that the number one best thing any of us can do in fitness is to do the exact same thing; follow our hearts.

Cardiovascular fitness has long been measured by the ability of our hearts to maintain a healthy heart rate during different types of aerobic activity. There have been heart rate zones which have been titled aerobic zone, fat burning zone, and anaerobic zone simply by the number of heart beats per minute. There are fitness test and stress test that are designed to measure ones fitness level by how the heart reacts both during exercise and during recovery after exercise. We have the American Heart Association which is a national association built on and around having a healthy heart.

Our bodies are built around, governed by, and depend upon our hearts for every single function we have and is truly the center of our health. Doesn’t it make sense to be aware and record our heart rates during ALL types of exercise? Absolutely! Not only did I design my brand new It’s All Heart fitness program around the heart but I take and record my heart rate during all of my exercise days including anaerobic (weight training) exercise days.

It’s amazing what you can learn about your heart when you start paying attention to your heart rate. In fact, you would be surprised to learn what your heart does during weight training (anaerobic exercise). I use a heart rate monitor during all of my workouts and it records the following:

• Exercise duration
• Calories burned
• Fat burned
• Average heart rate
• Max heart rate
• Min heart rate
• Amount of time in aerobic zone

Once you get 5-6 weeks of data from your heart rate monitor or from just taking your heart rate at different times during exercise, you can start making changes within your workouts to see how these changes affect your heart rate. And, you can see where you need to improve your heart rate.

Here are some of the things I have found out by recording my heart rates during exercise.

• My max heart rate is higher when I lift heavier weights like in the 4-6 repetition range but my average hr is lower because my rest periods between sets is longer.
• My max hr is lower but my average hr is higher when I do higher repetitions like 10 reps because my rest periods between sets are much shorter.
• All of my hr numbers are higher when I do not get enough sleep the night before
• All of my hr numbers are higher when I change exercises
• My hr numbers are higher when I work out later in the day
• All of my hr numbers are the highest when I train legs

These are just a few of the things I have learned about my heart during exercise. I have been taking heart rates for the last 5 years and at this point, I can predict with great certainty, what my hr will be according to which exercises I will be doing on any given day. I also know when my heart is at its best and which resistance exercises and repetitions cause my heart to work in different ways. These are great things to know about your heart and will help you understand how your heart reacts to different types of exercise.

So, the next time you here someone saying “follow your heart”, do exactly as they say.