When you think body type you probably think thin, medium build, large build and so on… but what we really mean when we say body type is actually your somatotype. Your somatotype is a concept developed by American psychologist Dr William Herbert Sheldon in the early 1940s and refers to the idea there are three general body compositions people are predetermined to have: endomorph, mesomorph and ectomorph. (1)

According to Dr Sheldon, these are the three main male body types/compositions:

Once you have a grip on your specific body type and metabolic conditioning, you are far more equipped to start exercise programming effectively. The ability to compound or develop progression tiers based on whether you are an Endomorph, Mesomorph or Ectomorph is critical to ensuring you aren’t wasting your time in the gym. According to Andrew Payne from the National Academy of Sports Medicine, the relationship between body type and overall composition is multifaceted.

As an endomorph, training should first focus on fat loss techniques until you’ve reached your ideal body composition and a good level of cardiovascular health. Basically, you want to maximise calorie burn in each workout session and improve your metabolic efficiency with high-intensity training. Strength training can then be used to strengthen muscles and stabilise joints. A high protein diet with balanced carbs and fats (while eating in a slight calorie deficit) will help you achieve your body shape goals. (4)

Lucky news if you’re a mesomorph – you do have it slightly easier than other male body types. You have a pretty efficient metabolism and a good amount of muscle mass to reach whatever fitness goal you have with a small amount of foundational work. You want to be eating for specific fitness goals, increasing or decreasing your calories to control your body composition. Increase your protein if you want to gain muscle, or lower your protein if you’re happy with your current muscle mass. Keep carbs and fats balanced.

Ectomorphs have a highly active metabolism and can be described as lanky with a thin bone structure. It can be hard for ectomorphs to put on weight and keep it on. Training as an ectomorph should focus on hypertrophy (an increase in muscular size achieved through exercise), so maximal strength training is key. Cardio should be minimised in an effort to reduce overall energy expenditure. A high protein with balanced carbs and fats with a focus on neutral calorie consumption is key.

Importantly, genetics plays a significant role in your body structure, so you must take stock of the situation from a medical perspective. In an interview with NBC News, Harvard medical professor C. Ronald Kahn, M.D. revealed that determining how much influence you receive from your gene pool is a challenging code to crack.

If you’re looking to change your body shape and body type, the good news is physical training has a strong influence on improving your body composition. For endomorphs, you want to focus on high-calorie burning exercises like interval training circuits. For mesomorphs, you want to focus on a combination of strength and cardio training depending on your body shape goals. For ectomorphs, strength training is vital in helping you grow your muscle, while any training that is high energy should be reduced. (4)

We all know calories in versus calories out affect our body composition, and the same is true across all body types. For endomorphs, you want to focus on eating in a calorie deficit while focusing on consuming plenty of protein. Mesomorphs have the luxury of eating however they want based on their body goals, so if you want to bulk, eat more protein. If you want to lose weight, tailor your diet to be eating in a calorie deficit.  Ectomorphs want to be focusing on eating in a calorie surplus to ensure you don’t lose weight or muscle mass, with a focus on high-protein foods and a good balance of carbs and fats.

While metabolic rate is heavily influenced by genetics, you can condition your metabolism through training and diet. Your metabolism will adjust to your energy intake and physical activity. If you’re mainly an ectomorph or endomorph, with the right diet and training your metabolism will begin to show more mesomorphic traits over time.

The bottom line is your body type isn’t set in stone. Your overall somatotype is a reflection of your currency training, diet and lifestyle choices combined with uncontrollable factors like genetics and your surrounding environment. The human body is incredibly adaptable and consistently searching for homeostasis (i.e. balance) within its environment. With the right training and diet you can shift your somatotype, but don’t expect it to happen overnight. A certified PT or nutrition coach will be your best friend and can help you achieve your body shape goals.