Monday, April 29, 2013

Why High Intensity Interval Training Is Better Than Steady State Cardiovascular Training

Endurance training helps develop a stronger cardiovascular system, including heart, muscles, lungs and blood vessels, and can add years to your life.

 Cardiovascular endurance also enhances your heart's ability to control the oxygen flow to all of your muscles, improving your overall workout efficiency. You should aim for 30 minutes of daily activity for improved endurance performance.

Since the heart is a muscle, it can be strengthened just like the other muscles in your body. The American College of Sports Medicine recommends 30 minutes of daily physical activity.

Just 30 minutes per day can improve your endurance, give you stronger muscles, better sleep and reduced stress levels!

Some examples of steady State endurance exercises (SSCT) include running, walking, swimming, bicycling, dancing, but any sport or exercise that can be performed for longer periods of time to get the heart pumping is considered SSCT.

There is a better alternative though. High intensity interval training (HIIT).
HIIT can boost athletic performance, improve the health of recreational exercisers, and provide the benefits of SSCT in less time and fewer workouts!

SSCT is considered aerobic exercise (running, biking, rowing, swimming, etc.) for greater than 20 min. HIIT is considered a short amount of time exercising at maximum intensity followed by short rest.

Timing varies from method to method, but it usually follows a 2:1 ratio of intense exercise to rest. For example, Tabata (a form of HIIT) is 8 rounds of 20 seconds of intense exercise followed by 10 seconds of rest.

Both methods increase stroke volume (amount of blood pumped per heart beat), heart contractility (force of each contraction), and left ventricle heart mass. Both of these variables increase blood flow and the amount of O2 supplied to your muscles. But HIIT:

• Improves stroke volume better than SSCT
• Improves VO2 Max more effectively, which is important for fighting heart disease
During aerobic exercise, mitochondria (energy factory of a cell) use O2 to manufacture adenosine triphosphate (ATP- the energy source of a cell) through the breakdown of carbs and fat. As mitochondrial density increases,

more energy becomes available to working muscles. HIIT leads to an increase in mitochondrial oxidative enzymes; thus, making your body more effective at breaking down carbs and fat for fuel.

HIIT also has greater excess post exercise O2 consumption (EPOC) after exercise sessions than does SSCT. O2 consumption (and thus caloric expenditure) remains elevated as working muscle cells restore physiological and metabolic factors in the cell to pre-exercise levels.