Body Shape, Size and Metabolism – Is It All Genetics?

Are you destined to follow the body shape of your mother or father?  Or can your efforts at the gym transform your physique to that of a supermodel or elite athlete?

We asked Lisa Middleton, Advanced Sports Dietician what she thought.

“The answer is not simple, but we do know that body shape, size and metabolism are related to both our genetic predisposition and lifestyle choices,” Lisa says.

“If there is a history of obesity in your family should you just give up now?  Or should you work your backside off to get the results you dream of?


Body fat

  • Genetics may determine where we store body fat.
  • How much we store may be more a result of choices.
  • Whether you are an apple shape (fat stored around the trunk) or a pear (fat located peripherally), you can change the size of your shape through effective exercise and nutrition.

Muscle mass

  • The ability to bulk up relies on a number of factors, with genetics and gender right up there.
  • Individualised training and nutrition will bring results, but keep in mind your potential genetic limitations.
  • *Note – not everyone can achieve a ‘ripped’ six-pack.


  • The rate at which your body uses energy is your metabolic rate – the amount of kilojoules you burn per kilogram body weight per day.
  • Basal metabolic rate is directly related to the amount of muscle you have.
  • More muscle = increased basal metabolic rate.


Studies have shown that genetic factors contribute 25% – 40% to the risk of obesity and some researchers believe genetics are responsible for at least 50% of all obesity cases. The good news is that we still have at least 50% to play with!   Some people may have to work that little bit harder due to their genetic background, but remember, the culprit is often family ‘habits’ rather than genetics.