Why Your Exercise Should Include Anaerobic Activity

Many of my patients ask me which form of exercise is better, cardio or strength training.

In my observation, women generally tend to favor cardio, while men tend to favor strength training.

Both cardio and strength training are an important part of an integrated exercise routine. Anaerobic training, however,  has some metabolic advantages when it comes to weight loss and building lean body mass.

In addition, too much cardio can be antagonistic to many of the favorable adaptations produced by weightlifting , whereas weight lifting, at specific intensities, can enhance aerobic adaptations, making this form of conditioning superior for many of those looking to become, fit, lean and healthy.

Energy 101

There are three metabolic energy pathways:

  1. Phosphagen system
  2. Glycolytic
  3. Aerobic


Phosphagen System

During short-term, intense activities, a large amount of power needs to be produced by the muscles, creating a high demand for the energy substrate Adenosine Triphosphate (ATP). The phosphagen system (AKA the  ATP-CP system) is the quickest way to resynthesize ATP. It is the predominant energy system used for all-out exercise lasting up to about 10 seconds. Since there is a limited amount of stored Creatine phosphate (CP) and ATP in skeletal muscles, fatigue occurs rapidly. No carbohydrate or fat is used in this process.



Glycolysis is the predominant energy system used for all-out exercise lasting from 30 seconds to about 2 minutes and is the second-fastest way to resynthesize ATP. During glycolysis, carbohydrate, in the form of either blood glucose (sugar) or muscle glycogen (the stored form of glucose), is broken down through a series of chemical reactions to form pyruvate. Once pyruvate is formed, it has two possible fates:

  1. Conversion to lactate
  2. Conversion to  acetyl coenzyme A (acetyl-CoA)

Conversion to lactate occurs when the demand for oxygen is greater than the supply (i.e., during anaerobic exercise).

Conversely, when there is enough oxygen available to meet the muscles’ needs (i.e., during aerobic exercise), pyruvate (via acetyl-CoA) enters the mitochondria and goes through aerobic metabolism.


Aerobic System

The aerobic system is dependent on oxygen. The metabolic reactions that take place in the presence of oxygen are responsible for most of the cellular energy produced by the body.  The aerobic system (e.g. Krebs cycle and the electron transport chain) uses blood glucose, glycogen and fat as fuels to resynthesize ATP in the mitochondria of muscle cells. Steady state lower intensity exercise uses this system.


Summary of Energy System Characteristics


What Anaerobic Training Does

Anaerobic training adaptations occur in the body when we exert ourselves at about 85% of our max heart rate (220- Your Age) and above. When we train at this level of intensity for short bursts (e.g.  High Intensity Intervals), we create what is called EPOC (Excess Post-Exercise Oxygen Consumption).

EPOC creates an after burn effect of calories, whereby calorie burning occurs at rest for 1-2 days post exercise. This type of training can be incorporated into both cardiovascular exercise as well as strength routines.

With cardiovascular exercise one can do sprint intervals. With strength training you can perform explosive movements or do supersets


Some effects of anaerobic training can include:

  1. Burning more calories from fat at rest
  2. Developing strength
  3. Increasing lean body mass (i,e. a more defined body)
  4. Increasing VO2 max. (i.e becoming more fit)
  5. Loss of visceral fat
  6. Increasing growth hormone
  7. Favorable effects on insulin resistance
  8. Preserving bone density while improving muscle mass, strength, and balance

*Due to the nature of anaerobic exercise, it is a time efficient way of getting exercise in for those with busy schedules.


Anaerobic conditioning should be preceded by building the proper foundation, i.e. An aerobic base and core stabilization.

Because of the demand on one’s body,  proper maintenance is recommended, e.g.  deep tissue massage, myofascial release, chiropractic, stretching, foam rolling, adequate nutrition and recovery.

Regardless of your age or gender, If you’re looking to become more fit and tone, increase your metabolism and/or enhance your health, including anaerobic exercise is a quick and effective means of achieving these goals.



As with any form of exercise, a proper assessment is essential for creating the right program, preventing injuries and achieving optimum results.


About the Author

Dr. Geoff LecovinNaturopathic Physician/Chiropractor/Acupuncturist/Certified Strength and Conditioning Specialist/Corrective Exercise Specialist/Performance Enhancement Specialist/Certified Sports Nutritionist/View all posts by Dr. Geoff Lecovin