To understand this debate, we must first understand metabolic exercise. Metabolic training is the increased capacity and efficiency of the energy pathways to store and deliver energy for activity. Most people commonly refer to this as, “cardio.” There are two main energy pathways used to provided energy for activity, aerobic and anaerobic.
Aerobic activity uses oxygen to produce energy and is associated with low to moderate activity over 90 seconds...think marathoner. The benefits of this type of training is increased cardiovascular function and a decrease in body fat. The negatives are a decrease in mass, strength, power, speed, and anaerobic capacity. Most people seem to gravitate towards steady state aerobic training, by walking on the treadmill or using an elliptical machine at low to moderate intensities, but is this the most efficient way to decrease body fat? Before I clarify, let's first take a look at anaerobic activity.
Anaerobic activity involves higher intensity exercise, like weightlifting or sprinting for example, and utilizes two main energy systems. The first is ATP-CP where energy is derived from the resynthesis of Adenosine Tri-Phosphate from Creatine Phosphate until the energy stores are depleted. This system is associated with quicker movements and only last about 5-7 seconds. The second is our glycolytic system which resorts to the breakdown of blood glucose and stored glycogen for energy. This system falls between the other two, and therefore lasts somewhere between 7 and 90 seconds.
To further understand the differences between aerobic and anaerobic training, consider the following: Let’s say you perform a low intensity (aerobic) exercise burning 50% fat for fuel while a friend performs a higher intensity exercise (anaerobic) burning 40% fat for fuel. Based on this you would assume its better to work at a lower intensity to decrease the most body fat, right? Not exactly. Lets say you burned 100 calories (50 fat calories) in 20 minutes while your friend burns 160 calories (64 fat calories) in 10 minutes. As you can see, anaerobic exercise is more beneficial as it burned 14 more fat calories, and in half the time! If that's not convincing enough, consider the benefits of anaerobic exercise which includes, increased cardiovascular function, decrease in body fat, increase in muscle mass, improved strength, improved power,improved speed, and improved aerobic capacity. The only downside to all of this is that anaerobic training requires an aerobic foundation, and that just makes sense. If you can’t jog or climb stairs for any duration without feeling out of breath, you're certainly not ready for sprints and box jumps!
Remember, physical fitness involves a combination of cardiorespiratory endurance, strength, flexibility, power, speed, coordination, agility, balance, accuracy, and lets not forget mental toughness. To pursue fitness excellence you must physically train to optimize your performance in all of the physical abilities and not maximize your performance in one ability at the expense of others. What many people are failing to realize, is that focusing on extended aerobic training is doing little or nothing to improve the physical abilities necessary for fitness excellence, and in most cases are in fact decreasing their performance! So what is the solution? Train ALL of the energy pathways by varying low intensity-long duration, medium intensity-medium duration, and high intensity-short duration metabolic training. The truth is most activities encountered in sport, work and life in general are often a combination of all the energy pathways seamlessly flowing from one to another. So, it's not so much of an aerobic vs. anaerobic debate after all, for you need both of them for optimum fitness. Solution: Train at higher intensities most of the time, and mix in some lighter cardio days for recovery and balance. Obviously sleeping and eating well goes without saying. Do that, and it won't be long before you notice your body getting tighter and leaner! Happy Training!