Low or High Intensity Training?

The internet is so full of different exercise regimens, routines, 30-day challenges, and new years fitness goals. What actually works? Looking at basic, evidence-based, movement physiology. The two main types of exercise categories are aerobic and anaerobic. Aerobic exercise is low-intensity movement that allows for high amounts of oxygen. The time frame involved is 2 to 30 minutes. On the other hand, anaerobic exercise is high intensity movement that allows for little amounts of oxygen. The time frame involved is 10 seconds to 2 minutes. Both aerobic and anaerobic movements have benefits for the body and can be practiced while prioritizing different health goals. Read more below.

Aerobic Versus Anaerobic Exercise:

Low to moderate intense movement, or aerobic exercise, allows our bodies to create much more ATP (energy); this helps us partake in exercise for longer periods of time. After around 60 to 90 minutes of prolonged, low-intensity movements, our glycogen stores will typically be close to depleted. At the same time, our bodies overall performance capacity is around 50% of optimal levels. Snacks can be helpful to replenish sugar stores and energy levels in the body, especially simple sugars for quick use. Although we deplete almost all of the glycogen within our muscles after 60 to 90 minutes, we still have additional glycogen stored in our liver for blood sugar moderation.

Interestingly, because aerobic exercise is more prolonged, more fat is used and therefore, more fat is burned. At the end of the day, the higher intensity the workout, the less fat will be used to support the on-going work being done. This is why so many "exercise protocols and regimens" are not successful or sustainable. Muscle training, which is an example of aerobic exercise, promotes the production of myoglobin, leading to larger mitochondria in our bodies. Larger mitochondria encourage a balance of using glucose and fat for energy to preserve long-term stores of glycogen for the brain. Fat is naturally prioritized because larger mitochondria will produce more enzymes that target fat.

Anaerobic exercise is great for building and supporting cardiac strength. Some examples include short sprints or HIIT workouts (high intensity interval training), etc., HIIT is made to target anaerobic exercise, which is between 10 seconds to 2 minutes of super high intensity movements. This challenges cardiac strength and supports long-term cardiac health. Anaerobic exercise also produces non-beneficial side products, such as lactic acid. Lactate, or lactic acid, causes higher levels of fatigue and soreness in our muscles and isn't as sustainable in high amounts.

All in all, there is a special importance in finding balance between low intensity and high intensity training. Stay tuned for more information on evidenced-based exercise recommendations!