ULTIMATE PT
august september 2011
Weight-loss
Many clients still harbour opinions about weight loss that are simply
wrong. While you’ll recognise the following myths are just that – myths
– we’ve enlisted the help of PTs Kristoph Thompson and Mike Heatlie to
provide some quick and simple cue cards to print out and give to clients.
“I’m doing lots of sit-ups to get a six-pack”
A study conducted at the University of Massachusetts in the
mid-1980s8 assessed the fat loss of 13 male subjects following a
vigorous 27-day abdominal exercise training programme. Fat biopsies
were obtained from the subjects’ abdomens, buttocks and upper backs
before and after the exercise programme. The results of the study
revealed that fat decreased similarly at all three sites – not just in the
abdominal region.
Conversely, a more recent study published in the American Journal
of Physiology – Endocrinology and Metabolism found that exercising
muscle does have an effect on local fat, especially the subcutaneous
fat adjacent to the muscle. The study concluded that ‘an acute bout of
exercise can induce spot lipolysis and increased blood flow in adipose
tissue adjacent to contracting skeletal muscle’. In summary, if you want
to reduce fat in a certain area, such as your stomach, whole-body
exercise still results in more overall body fat loss than working local
muscle groups. (Kristoph Thompson)
“I can’t lose weight
because of my genetics”
There is a strong body of research which suggests
that weight is largely genetically determined.
Studies on twins raised apart have shown BMI to
be very similar1, 2 and further studies have found
adopted children to have a weight that correlates
more closely with their biological parents than
their adoptive parents.3
Scientists have identified that certain genes
are connected with obesity4 but have also
emphasised that having these genes don’t mean
that a person will become obese. Many people
carry these genes and still manage to maintain a
healthy weight – the most important factors are
exercise and healthy eating. (Kristoph Thompson)
“I’ve been told that to lose weight my training should be low intensity”
It is true that fat oxidisation is higher during lower intensity activity5 than higher intensity work, but this isn’t where the story ends.
Weight loss is the result of calories burned throughout the entire day or week, not just what happens during an exercise session.
Studies have shown there is no significant difference in calories burned 24 hours after a high- or low-intensity workout 6,7 and
after a period of weeks there is no difference in total fat burned. However, the fundamental difference is that you have to train for
longer with the low-intensity workout than the high-intensity workout.
Studies have also shown that those following a low-intensity programme lose muscle mass while those doing high-intensity
training gain muscle mass. This poses the question of whether the total weight loss attributed to fat burning programmes is from
pure fat loss or a loss of muscle mass as well. (Kristoph Thompson)
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FITPRO NETWORK | AUGUST SEPTEMBER 2011
ULTIMATE PT
myths
“Doesn’t
muscle turn to
fat if you stop
exercising?”
To download these cue cards visit
www.fitpro.com/cuecards
“To lose weight you should concentrate on cardio training”
Muscle cells and fat cells are
anatomically different and it
is impossible for one to ‘turn
into’ the other. We all have a
predetermined amount of fat
and muscle cells but what can
change is body composition – the
percentage of muscle and fat we
have in our body. When you train
your muscles, your muscle cells
grow in size, giving a more toned,
muscular appearance. If you stop
training them altogether they
will begin to shrink. If you are
simultaneously consuming more
calories than you burn, your fat
cells will begin to increase in size,
this is what gives the illusion that
muscle is turning into fat. What
is really happening is that your
body composition is changing to
a higher percentage of fat and
a lower percentage of muscle.
(Kristoph Thompson)
Firstly, cardio training needs to be defined properly. If one is performing 50-60 minutes of
cardiovascular training using the cross-trainer, running, cycling etc. at the same moderate
pace then this is not an effective fat-burning protocol even if one is burning 600 calories.
This type of training does not stimulate the powerful fat-burning hormones, such as
growth hormone and testosterone, and can actually breakdown muscle tissue, resulting
in a fall in metabolic rate.
Additionally, if the same cardio workout is being performed consistently then the body
will adapt to it in time, leading to less stress on the body. Weight training, performed
correctly, and cardio interval training, are better methods of training for burning body fat.
(Mike Heatlie)
“Muscle weighs more than fat”
It is almost ludicrous to suggest that one thing weighs more than another. One pound
of fat weighs the same as one pound of muscle. How on earth can fat weigh more than
muscle, or vice versa, without giving a tangible example? Muscle tissue is denser than fat
tissue and this is where the myth emanates.
Five pounds of fat will be larger in size than five pounds of muscle, but they still weigh
the same. A person who weighs 10 stone and has 15% body fat will look smaller than
a person of the same weight but who has a body fat percentage of 30%. If clients are
failing to lose weight, it may be that they are losing body fat, and adding muscle tissue,
which is denser – so they’ll be smaller, but weigh the same. (Mike Heatlie)
Mike Heatlie
Mike holds a 1st class Bachelors degree in Sport and Exercise Science and two masters degrees in Medicine Science in Sport and Exercise
and Strength and Conditioning. www.mikeheatliepersonaltraining.com
kristoph thompson
To view the references related to this article please visit www.fitpro.com/references
AUGUST SEPTEMBER 2011 | FITPRO NETWORK
FITPRO.COM
Kristoph is a strength and conditioning coach with a master’s degree in Human Performance. He is an associate lecturer at the University
of Brighton and is currently studying for a PhD. www.kristophthompson.com fn
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