Of all the destructive things we can do in the gym or within our fitness program, excessive long-slow cardio is it. Why then do so many seem to do it?

For a start just because others are doing it doesn’t make it right for you or even right full stop. “Stupid gym shit” (excuse the colloquialism – SGS) unfortunately features prominently in many people’s gym routines, men and women and top of this list is long, slow trotting on a treadmill, long slow grinds on a bike or rower etc.

Human’s are intermittent functioning organisms. We pulsate and this is never more evident than in our breathing and heart function and this pulsing action delivers blood, oxygen and fat into the working cells. So when it comes to energy supply this aerobic function serves us admirally providing our every day low octane fuel that keeps us moving, albeit slowly. When the requirement for higher octane fuel is required our body switches to using stored sugars known as glycogen and this gives us much more power and speed.

It is a physiological fact that when we use this energy system frequently to engage in speed and power based activity, our body shape optimises to cater to the environment we’re asking it to operate in and delivers growth hormone (GH) to shed fat and build lead muscle. This is optimising our human function and what we are hot-wired to do if we use our human organism the way it was intended.

We aren’t supposed to be fat, we just get that way when we don’t use our bodies the way they’re supposed to be used. Fatness is a relatively recent development in human evolution, being slow, overweight and generally immobile didn’t augur well when hunting food or trying to remain not being food for a predator. Clearly our evolutionary pathway rewarded those that were buying into the hunter-gatherer concept by providing lots of GH and optomising endocrinal function.

So back to long slow cardio. Research has determined that this type of activity increases release of cortisol and this hormone works exactly opposite to GH, holding fat and stunting muscle growth. In fact people that engage in excessive long slow cardio can technically be skinny fat. This is not a condition you want to be in as the linked article states.

The type of cardio you SHOULD be doing is HIIT, intervals of 30-45-60 seconds with the same period resting, trying to work at near max levels through each work set. It will only take you 5-10 minutes to elicit the desired outcome and why most good coaches use it at the end of sessions!