Introduction: Aerobic vs Anaerobic

 

"Aerobic" and "anaerobic" are terms used to describe how cells within the body produce energy and refer to energy systems.

 

Aerobic means "with oxygen" and refers to the body producing energy with the use of oxygen. This typically involves any exercise that lasts longer than two minutes in duration. In general, aerobic exercise is performed at a moderate level of intensity over a relatively long period of time. For example, running a long distance at a moderate pace is an aerobic exercise, but sprinting is not. Playing singles tennis, with near-continuous motion, is generally considered aerobic activity, while activities with brief bursts of energetic movement within longer periods of casual movement may not be aerobic. It is most common for aerobic exercises to involve the leg muscles, primarily or exclusively. 

 

Examples of aerobic exercise:

 

  • Running (a long distance at a moderate pace)
  • Swimming
  • Dancing
  • Jogging
  • Hiking
  • Stair climbing
  • Jumping rope
  • Soccer, Basketball, Tennis...

 

Anaerobic means "without oxygen" and refers to the body producing energy without oxygen. In practical terms, this means that anaerobic exercise is more intense, but shorter in duration than aerobic exercise. The biochemistry of anaerobic exercise involves a process called glycolysis, in which glucose (blood sugar) is converted to adenosine triphosphate (ATP), which is the primary source of energy for cellular reactions. Anaerobic exercise may be used to help build endurance, muscle strength, and power.

 

Some examples of anaerobic exercises include:

 

  • Sprints
  • High-intensity interval training (HIIT)
  • Strength training (pushups, pull-ups, squats... )

 

High-intensity interval training (HIIT)

 

High-intensity interval training (HIIT) is a training protocol alternating short periods of intense or explosive anaerobic exercise with brief recovery periods until the point of exhaustion. The method involves exercises performed in repeated quick bursts at maximum or near maximal effort with periods of rest or low activity between bouts. The very high level of intensity, the interval duration and number of bouts distinguish it from aerobic activity, because the body significantly recruits anaerobic energy systems. Though there is no universal HIIT session duration, a HIIT workout typically lasts under 30 minutes in total as it uses the anaerobic energy systems which are typically used for short, sharp bursts. The times vary, based on a participant's current fitness level. Intervals of exercise effort tend to range from 20 to 45 seconds but no longer than 75 seconds, at which point the aerobic system would then kick in.

 

Procedure and Eexamples:

 

HIIT exercise sessions generally consist of a warm up period followed by repetitions of high-intensity exercises separated by medium intensity exercises for recovery, then a cool-down period. The high-intensity exercise should be done at near maximum intensity. The medium exercise should be about 50% intensity. The number of repetitions and length of each depends on the exercise, but maybe as little as three repetitions with just 20 seconds of intense exercise. The specific exercises performed during the high-intensity portions vary.

 

There is no specific formula for HIIT. Depending on one's level of cardiovascular development, the moderate-level intensity can be as slow as walking. Here are a few simple examples of HIIT workouts: 

 

  • Using a stationary bike, pedal as hard and fast as possible for 30 seconds. Then, pedal at a slow, easy pace for 2–4 minutes. Repeat this pattern for 15–30 minutes.
  • After jogging to warm up, sprint as fast as you can for 15 seconds. Then, walk or jog at a slow pace for 1–2 minutes. Repeat this pattern for 10–20 minutes.
  • Perform squat jumps as quickly as possible for 30–60 seconds. Then, stand or walk for 30–60 seconds. Repeat this pattern for 10–20 minutes.
  • Perform 10 pushups at a time. Rest for 30 seconds, and then do 10 more. To increase the difficulty, rest for 15 seconds instead of 30 (and/or do more pushups at a time). Repeat this about 8-15 times (as you progress, you can increase the number of repetitions).
  • Combine different exercises: For example, you’ll start by performing a 15 second sprint. From there, drop down and do 10 pushups, followed by 10 squats. Rest for 30 seconds to 1 minute, and then repeat. 

 

Please note that these are only examples, and that the number of repetitions as well as the duration of the exercises depends on your current fitness level. While these examples can get you started, you can modify your routine based on your preferences. 

 

HIIT and Type 2 Diabetes

 

Recent research has shown that high-intensity interval training (HIIT) can promote improvements in glucose (blood sugar) control and cardiovascular health in individuals with type 2 diabetes. However it may not be safe or suitable for everyone. People with diabetes or any underlying condition associated with diabetes and metabolic syndrome should seek the guidance of an accredited exercise physiologist when considering adopting a HIIT workout. This type of exercise should always be considered on an individual basis.

 

Several studies investigating insulin response to HIIT reported a significant improvement (23% to 58%) in the increased insulin sensitivity. In non- diabetic healthy subjects, improvement in fasting insulin levels and insulin resistance was 23%-33%, while in patients with type 2 diabetes, improvement in fasting insulin and insulin resistance was 46%-58%. On the other hand, it is reported that endurance exercise can improve long-term insulin sensitivity in both young and elderly people. In general, it can be said that the amount of insulin decreases with exercise, but sensitivity to it intensifies.

 

Since we are utilising our anaerobic system for energy production, we are using energy stores in the form of glycogen, which then needs to be replenished by glucose from our bloodstream. In doing so, we can see reductions in blood glucose levels, which may assist in reducing the need for regular medications as guided by your medical team.

 

HIIT increases hormone responses which makes exercising for chronic disease management so important. If you are someone also managing Polycystic Ovarian Syndrome (PCOS), this is an important consideration. While HIIT can assist with the management of type 2 diabetes or insulin resistance, many people managing PCOS find HIIT to be a difficult way to manage weight, as your body does not respond to hormone release the same way as someone who is just managing type two diabetes. If this is something that may impact you, seek the advice of an Accredited Exercise Physiologist to further explain these pathways.

 

According to research conducted by professionals at Aarhus University Hospital in Denmark, HIIT is the most effective form of exercise for reducing type-2 diabetes risk as it's associated with lowering blood glucose levels to healthy levels. The 2015 study showed that completing a short (10-minute) HIIT routine just three times a week was able to help even elderly and non-active volunteers dramatically reduce their blood glucose levels in just eight weeks time. Furthermore, researchers said that "significant abdominal fat mass losses were seen" in those who completed the three HIIT routines each week over the eight-week span itself.

 

 

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