The Truth About Cardio

WILL POUNDING AWAY ON THE TREADMILL HELP ME LOSE WEIGHT?

SHORT ANSWER: YES

BUT, it will negatively impact your body composition. So basically, if you run flat out on the treadmill for extended periods of time, you will breakdown muscle and adversely affect your metabolism!

Now first things first. When speaking of cardio to “shred up” or “get lean”, there are generally 3 ways we can perform cardio (from a purely aesthetics point of view).

1. Low Intensity Steady State (65% of our Max Heart Rate of less)
2. Moderate-High Intensity Steady State  (65% or greater of our Max Heart Rate)
3. High Intensity Interval Training (H.I.I.T- bouts of sprints, followed by a rest period)

• NOTE: when i refer to CARDIO in this article i mean Moderate-High Intensity Steady State cardio! Also I will only discuss Moderate- High Intensity Steady State and High Intensity Interval Training. Low Intensity Steady State is a completely different matter altogether!

SO are you guilty of hammering away on the treadmill for extended periods of time? 

Im pretty sure we all have at some stage of our training.

The point of this article is not to discourage everyone from going for a jog or walk.

I aim to demystify some of the propaganda and idiotic information presented on the Internet and the rubbish tips and opinions thrown around the gym, proposing you MUST hammer yourself silly on the treadmill to drop body fat.

Please note that cardio does serve its purpose in weight loss regimes, especially for unfit and obese individuals, and if you enjoy a good old fashioned run go for it. But do so sparingly!

So do we need to do countless hours of cardio?

NOT at all!

When I first began my journey to transform my body I too am guilty of spending countless hours on the treadmill in an attempt to “shred up”.

God help me I wish I could have my time back! Let me tell you, I felt shithouse. Like a zombie, drained and zapped. It wasn’t pleasant. Not too mention I had about as much muscle as a 5-year-old girl!

So why is performing moderate to high intensity steady state cardio bad you ask?

Not only does cardio cause an increase in oxidative stress, which accelerates ageing, steady state cardio increases the free radicals produced by the body.

When your body cannot fight off these free radicals anymore (cannot produce enough antioxidants), it negatively affects your metabolism! that is it slows down the rate you burn calories throughout the day!

Another problem with moderate-high intensity steady state cardio is that it increases adrenal stress, which adversely affects your body composition.

By slowing down your metabolism, you are prone to an increase in fat as well as losing a tonne of muscle, which gives you that “skinny fat” look!

As you might have noticed, all marathon runners are lean, but have loads of flabby loose skin. Don’t get me wrong, they are amazing athletes, but not my body of choice!

What about a sprinter?

Ok, now that’s a physique to admire!

Do they run for strenuous periods?

NO. A sprinters efforts are explosive and in short bursts!

Now here’s some proof that running for extended periods of time is less beneficial than repeated efforts at a high intensity, known as High Intensity Interval Training (H.I.I.T).

A 1998 study in the Journal of Applied Physiology by Brett Dolezal and Jeffrey Potteiger tested the effects of steady state cardiovascular/ endurance training on individual Resting Metabolic Rate (the speed your body burns calories when inactive). Amazingly, this study demonstrated that steady state cardio had no impact upon resting Metabolic rate (RMR) whereas strength training improved RMR by 15%.[i]

Need I say more?

Ok, I will. Here’s another study that proves that H.I.I.T trumps flogging your legs senseless for minutes on end!

A 2008 study in the Exercise & Sport Sciences Reviews titled “Metabolic Adaptations to Short-term High-Intensity Interval Training: A Little Pain for a Lot of Gain?” highlights that only 6 sessions of 15 minutes of H.I.I.T training, over a period of 2 weeks increases skeletal muscle oxidative capacity, endurance performance and altered metabolic control during aerobic-based exercise.

Furthermore, a study was recently conducted testing whether or not extremely short duration high intensity interval training improves insulin action in young healthy men. The study found that such training reduces metabolic risk factors in young men and middle aged sedentary than a traditional aerobic regime would![ii] To read further, head to http://www.biomedcentral.com/1472-6823/9/3

One more?

Ok so in 2011, a collaboration of research was put forward by Stephen Boutcher titled “High-intensity intermittent exercise and fat loss”. In all evidence and studies researched, it was found that the effect of regular aerobic exercise on body fat is negligible; however, other forms of exercise may have a greater impact on body composition. It was also found that research-examining H.I.I.T indicates that it may be more effective at reducing subcutaneous and abdominal body fat than other types of exercise.

It doesn’t stop there, as mentioned above, Interval Training also significantly lowers insulin resistance and results in a number of skeletal muscle adaptations that result in enhanced skeletal muscle fat oxidation and improved glucose tolerance.[iii]

SO HOW IS DOING LESS BETTER?

Ever heard of EPOC?

Well EPOC stands for Excess Post Exercise Oxygen Consumption. So basically, our body is in debt of oxygen, also known as the “after burn”. When you train hard, you build up a deficit of oxygen, which is why you breathe hard after a short, hard bout of activity.

Evidence suggests that a high-intensity, intermittent-type of training (interval training) has a more pronounced effect on EPOC (creating a greater oxygen deficit).[iv]

Also, it appears that resistance training produces greater EPOC responses than aerobic exercise[v]. The research suggests that high-intensity resistance exercise disturbs the body’s homeostasis to a greater degree than aerobic exercise.

Yeah great, but why  do we burn more calories doing less training?

Well post exercise your body tries to replenish the oxygen deficiency and this causes the body to continually expend energy after exercise, thus increasing your resting metabolic rate for up to 48 hours! HENCE, H.I.I.T increases burns more calories for a longer period of time!

TO SUMMARISE:

Cardio wont make you fat, but running continuously at a high intensity will negatively impact your body composition by increasing your cortisol levels. This makes it harder to recover and detrimental to any efforts in gaining muscle- which gives us that toned, shaped look.

If you enjoy running and your are healthy, then by all means feel free to run! Just bear in mind that if your goals are to look as lean and defined as possible, steady state cardio is not the way to go!

Perform H.I.I.T 2-3 times per week in addition to your resistance training, as it will lead to an increase in resting metabolic rate, anabolism and improve your body composition.