Game of Thrones: What would happen if you tried the same diet as The Mountain

"If you want to grow big and strong, you’ll need to eat up!"

It’s a piece of advice we’ve probably all heard at some point in our lives. But at 6ft 9in (2.06 metres) and 180kg, and with the strength to deadlift almost 1,000lbs, few will have taken it as seriously as Icelandic strongman Hafþór Júlíus Björnsson.

Björnsson plays “The Mountain” in hit television series, Game of Thrones, a monstrous warrior who crushes his enemies' heads with his bare hands. And in the real world, he is also one of the world’s strongest men.

But what does this human giant eat? Well, we now know – because he has posted details of his daily routine on Instagram. And it is quite a feast. An analysis by Men’s Fitness reveals the much-loved star consumes around 12,000 kcals a day, close to five times the requirement of an average Joe. But how does this diet support his performance aims of becoming the World’s Strongest Man – and could it be refined to improve the physique of mere mortals like you and me?

Let’s first address The Mountain’s supplements. The use of branched chain amino acids (BCAAs) is common practice among gym goers. However, no scientific evidence exists that supplementing BCAAs (isolated components of complete proteins) is any more effective for stimulating muscle growth than high quality protein, such as milk. However, BCAAs do seem to be useful in offsetting the soreness associated with muscle damage – although they do not improve the recovery of muscle function.

For those new to lifting weights, BCAAs may therefore help reduce the severity of muscle soreness that inevitably occurs in the first few sessions at the gym. But the effect is small and a more cost effective alternative may be a large glass of milk which can limit markers of muscle damage post workout. Milk or chocolate milk is also a convenient source of easy-to-consume liquid calories – handy when you’re faced with needing 12,000 a day.

The next supplement that appears heavily in The Mountain’s diet is the non-essential amino acid glutamine. There’s no doubt that Björnsson looks incredible on his diet, but there is little evidence to support the purported performance-enhancing effects of this supplement.

So what about Björnsson’s protein intake? How much protein a man of this size needs is a difficult question to answer and will depend on a range of factors. We certainly would caution against a single broad recommendation. However, there are some studies, which can be used for guidance.

Retrospective analysis of a range of protein feeding dose response studies has led to a suggestion that in young, healthy adults, 0.4g/kg of protein per meal is sufficient to maximally stimulate the muscle growth response.

This means that a man of The Mountain’s size should consume in the region of 70g of protein per meal. And as we now know, Björnsson consumes anywhere from 50g (midnight snack) to 150g (main meal) of protein per meal.

Evenly distributing protein intake throughout the day also seems to offer some benefits when it comes to muscle growth. Björnsson seems to eat every two to three hours, which based on a study, seems to be a sensible approach. It may also help improve the effects of resistance training.

For an average man, this would look like 30g of protein (a large chicken breast) every three to four hours. For The Mountain, it would scale up to six or seven 70g doses of protein every three hours, making for a total recommended intake of 420g of protein per day. About half of his current intake (850g).

But is consuming protein at night of any benefit? Recent evidence demonstrates that protein that is consumed close to bed or while asleep (naso-gastric feeding) is successfully digested and absorbed and the subsequent amino acids incorporated into muscle. This means that eating before bed or during the night may be a viable strategy to increase the supply of amino acids to our muscles. Something which may help someone consuming over 10,000 calories a day to achieve their required intake. However, most mere mortals should be able to consume their recommended total daily calorie intake (about 2,500 Kcals/day) without interrupting sleep.

Strongman training and strongman events involve a mix of maximal efforts (maximum deadlift, for example), “as many reps as possible” activities (axle press, for instance), and set workloads completed over the quickest time possible (the Atlas stones and tyre flips). The latter two event types can last 60 seconds or more and require very high intensities of work.

It’s difficult to come up with a carbohydrate dose recommendation without a clear picture of The Mountain’s training regime, but based on the above assumptions, he would require a carbohydrate intake in the range of 5-7g per kg of bodyweight per day. This would equate to a total of 900-1,200g of carbohydrate per day, which likely isn’t too far off Björnsson’s current intake of around 800g/day from food, plus whatever he consumes via his carbohydrate supplement (vitargo).

While Björnsson’s absolute fat intake is quite high (about 456g a day, equating to over 4,000 kcals from fat) as a percentage of his absolute caloric intake, it isn’t too far off the acceptable macro-nutrient distribution range of 20-35% for active people. His daily caloric intake is about 11,000 kcals from food and likely close to 12,000 kcals when his carbohydrate, glutamine and BCAA supplements are factored in. As a result, his dietary fat intake is close to 35% of his total calories and contains a high content of so called “heart-healthy” polyunsaturated fats from sources such as almonds, oily fish and avocados.

If this caloric intake is a true reflection of his energy needs then the only changes we would “tentatively” (we’re not arguing!) suggest would be to reduce his protein intake, redistribute it evenly over the day to have a minimum dose of 70g/meal and moderately increase his carbohydrate intake to suit his training needs on a day-to-day basis. We see no need for BCAA or glutamine supplements and he could benefit from consuming more of his calories in liquid form from sources such as milk or chocolate milk. Finally, he would be highly likely to benefit from a creatine supplement and possibly the strategic use of caffeine.

The primary problem with developing a nutrition strategy for a strongman competitor of this size is the amount of calories required to perform the training. While few of us will ever need to consume a diet like this, there are aspects of it that can be translated to support the performance of ordinary people. The key point is the regular intake of high quality protein sources spread throughout the day, advice which will undoubtedly assist the performance goals of The Mountain, but may also help the rest of us to achieve a healthy and functional old age.

Oliver Witard, Senior Lecturer in Health & Exercise Science , University of Stirling and Lee Hamilton, Lecturer in Sport, Health and Exercise Science, University of Stirling

This article was originally published on The Conversation. Read the original article.