For many people this statement would appear somewhat controversial or even counter-intuitive.  How can a style of exercise designed to build muscle also be your best means to burn fat?

The facts are quite clear on fat burning.  In the short term if you were to do an hour’s cardio you’d burn more in that hour than if you were to do an hour of resistance training.  However, once the hour of cardio finishes you stop burning calories.  When you do resistance training you continue to burn calories after the hour’s training has ended, by an affect called afterburn, and you also create an increased metabolic demand due to increased muscle mass.

This, in a nutshell, is how resistance training is superior for fat loss than cardio training.

But let’s break this down somewhat.  A hard cardio session could burn as much as four hundred calories in an hour.  Three hard cardio sessions like that would be a 1,200 calorie deficit.  In our scenario if we assume that the individual doing cardio is also running a 300 calorie deficit per day, from 1,500 calories down to 1,200 calories a day, this means that over the course of a week our individual has a three thousand calorie deficit.  This sounds like a lot, but it would equate to being 0.4kg per week.  If we assume our individual does this for a month they would be down 1.6kg after four weeks.

In the second month their body has now adapted to this calorie level and it is maintenance.  At the same time, the hard cardio sessions are only burning a hundred calories a session.  In month two we have a total deficit of 1,200 calories.  This would equate to a weight loss of around 0.15kg only. 

In month three, the cardio sessions burn fifty calories per workout as the individual has become almost wholly adapted to them, and the calorie maintenance level remains at 1,200 calories.  But in month three work commitments mean that some days that person is going out for work dinners and is unable to do their cardio sessions as often.  Instead of twelve workouts in a month this individual has only been able to do eight sessions.  And on the once weekly work dinner the individual has eaten 1,800 calories.  Over four weeks that is a net of two thousand calories extra a week, equating to a one kilo weight increase.  For three months of effort our individual has lost 0.75kg, and is severely disheartened as a result of the final month.  If they were to continue in the same way in month four they would actually end up 0.25kg above their start weight. 

Now lets assume similar circumstances for someone doing resistance training.  Again, our individual is working out three times a week.  Because they are new to resistance training their sessions only burn fifty calories a session.  However, the afterburn effect on the body is another fifty calories, and the metabolic adaptation, to cope with muscle growth and strengthening, is a further fifty calories.  This individual only has a slight calorie deficit, of one hundred calories per day.  Per month they are three thousand four hundred calories in deficit, which is 0.45kg. 

In month two, with better technique, each training session has a calorie burn of a hundred calories, an afterburn effect of a hundred calories and a metabolic adaptation of a hundred calories.  Again we will assume a hundred calorie deficit per day.  In a month we are six thousand four hundred calories in deficit. This is a loss of 0.82kg, taking the total loss to 1.27kg.

In month three, the same issues befall this person as happened to the cardio person; training drops to twice a week, and there is one work dinner per week.  However, those training sessions see further improvements.  Each one of these workouts now burns one hundred and fifty calories, and the after burn is one hundred and fifty calories also.  And because the metabolic rate has increased, our individual is already consuming 1,650 calories a day at maintenance.  They are at 1,550 calories six days of the week and 1,800 calories once a week.  This means that there are still in a deficit in month three, of four thousand six hundred calories.  That equates to a 0.6kg loss for the month, taking the total loss to 1.87kg.

So although there is a slower start to the weight loss, the resistance individual lost 1.87kg, whereas the cardio individual lost 0.75kg.

The key takeaway, however, to do with training and metabolic flexibility.  Resistance training enables the metabolic rate to increase, which means that occasions where you eat out has less of an impact on your weight loss.  Equally, as competence with resistance training increases so does the long term impact on weight loss, because you are able to ensure that the load you are working with requires continuous adjustment for adaptation. 

For this reason I believe resistance training is a key component for long term success for weight loss.

Are you interested in resistance training but don’t know where to start?  Then send an email to enquiries@rkfitness.co.uk