

The first rule of Fight Club diet is: eat lean to look lean. If you want to get stronger, and get a six pack but retain a really LEAN look, Hollywood has the perfect role model for you (if you are a man). The film might be 12 years old now but perfecting the diet to gain lean muscle mass and achieve that Brad Pitt as Tyler Durden look still very much resonates today. But balancing calorie intake with sufficient protein and the right amount of exercise can be tricky, with many assuming that the only way to pack on muscle is by eating all of the food.
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In fact, this is a misconception, as David Birtwistle, movement and nutrition coach and founder of performance coaching program Endeavour Life, handily points out: “most people eat too many calories when they're trying to build muscle mass, but you only need a surplus of about 10% in order to make visible gains”.
And look how lean he is. Dude is chiselled like a sculpture chiselled out by a full set of very expensive chisels.
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Of course, obtaining a fit, lean physique that handily reveals a washboard stomach but also packs enough muscle to avoid looking malnourished is slightly more complicated than just counting calories, so we’ve picked Birtwistle’s brains to put together a quick guide to achieving an enviable Fight Club bod.
Then all you need to do is follow a mixed martial arts workout regime, whilst being a figment of Edward Norton's imagination. Sorry, spoilers.
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The science behind the Fight Club diet
"When you train, muscle tissue is broken down at a microscopic level causing micro tears to the fibres. The foods that help to repair this are those groups that are high in protein, ideally that have a full amino acid profile, including the essential amino acids,” explains David Birtwistle.
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In slightly less baffling science lab talk, high protein foods that include the full gamut of essential amino acids are easiest to find in animal proteins, such as chicken, beef, pork, fish and lamb. But it’s also possible to obtain these if following a vegetarian or vegan diet by ensuring your meal plans include tings like chia seeds, tofu and quinoa - all of which are often regarded as boasting complete or near complete protein profiles.
“Animal sources all give the muscles a complete amino acid profile with sufficient quantities of protein, ideally around one gram per pound of body weight. However, we don't need to have animal sources of protein for every protein source. As long as the minimum protein requirement is met each day then you can combine both animal and vegetarian sources of protein to get the same results,” says David.
This is what your plate needs to look like
How to eat to gain lean muscle
Gaining lean muscle is a case of eating enough calories to build muscle mass without building fat tissue at the same time. “Most people eat too many calories when they're trying to build muscle mass, but you only need a surplus of about 10 per cent in order to gain muscle mass,” says David.
For example, if you eat 2000 calories per day to maintain your current level, you only need to eat 2200 per day to make marginal gains in lean muscle. “The other thing to consider is that building muscle mass takes time. For beginners, the best case scenario is going to be around 1 to 1.5% body weight increase per month from lean muscle tissue. For intermediates that have been training for around a year to two, you're looking at best 1% body weight increase per month,” david explains.
Unfortunately, for those who are more advanced gym-goers, who have perhaps been training for several years, you're looking at a best case scenario of only 0-5% body weight increase in lean muscle tissue per month. It’s a slow process.
So, rather than going into massive calorie surplus, like heavy-lifting strong men and women might, the best way to achieve a lean Fight Club look is to go into a slight calorie deficit to lose fat but maintain muscle mass by ensuring protein intake is high.
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Injecting the odd protein shake is encouraged
“The best foods to eat for this are going to be lean protein sources, such as chicken breast, beef and fish. Also, make sure you include a mixture of vegetables in your diet, because the high fibre count is going to be very beneficial too. In essence, you should select foods that deliver a big protein hit and fill you up, without too many additional calories. Limiting fat intake to around 25% of your overall daily caloric intake should do the trick,” says David.
David Birtwistle’s Example Diet
Breakfast
Two eggs
Two/three slices of wholemeal toast (with butter)
Steamed spinach
Lunch
Grilled chicken breast
Steamed wholegrain rice
Tomatoes, broccoli, green beans
Dinner
Lean rump steak
Sweet potato
Garlic mushrooms
Snacks
Protein shake or bars that are low in fat
Cereal and almond milk
Peanut butter on wholemeal toast
Leon has been writing about automotive and consumer tech for longer than he cares to divulge. When he’s not testing the latest fitness wearable and action camera, he’s out in a shed fawning over his motorcycles or trying not to kill himself on a mountain bike/surfboard/other extreme thing. He's also a man who knows his tools, and he's provided much of T3's drills coverage over the years, all without injuring himself.
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