It is well known the quantities of food strongman athletes may consume on a daily basis to fuel muscle hypertrophy and attain energy balance. Most notoriously, World Strongest Man 2017 winner Brian Shaw was known to consume ~12,000 kilocalories on his heavy training load days – which assuming that he hits basic DRV macronutrient values of 50% CHO, 35% FAT and 15% PRO would be an intake of 1500g CHO; 467g FAT; and 450g PRO in 24 hours. Similarly, on the set of Game of Thrones, Peter Dinklage recalls how Hafthor Bjornsson consumed a total of 7 whole chickens in one sitting (7,616 kcal; 45g CHO; 371g FAT; 1,050g PRO) – whether or not this is actually true remains elusive (and most likely not correct), but you get the point, strongman athletes eat big.
What may be lesser known is how a strongman’s athletic performance and general health may be impacted by their nutrition and how specific planning of dietary and supplemental strategies may drastically improve their chances of achieving 1st place on the event compared to if they possessed the generalized (or ‘bro’) view of “as long as I’m hitting 200g protein per day, I’ll be fine!”.
Is that Really your Resting Metabolic Rate or an Elephants, I Can’t Tell!
Now, these athletes aren’t just eating big because they’re hungry, neither are they eating 7 chickens per day to solely increase their fat-free mass (FFM). Rather, these athletes need to achieve energy balance to prevent muscle wasting and optimise performance – and this means to first consume enough kilocalories to reach their resting metabolic rate (RMR). You may have heard of RMR before, but if you require a refresher, it is the amount of kilocalories required to fuel your body at rest so that it is able to perform involuntary tasks such as breathing, blood circulation, organ function, and basic neurological efforts. As a 24-year-old male who is 87 kg and 191 cm tall with a body fat % (bf %) (estimate) of 17%, my RMR will be around ~2090kcal (Using Cunningham (1980) FFM-based equation). However, a strongman athlete with Hafthor Bjornsson-esque stats – Age: 31, weight: 180 kg, height: 206 cm; bf %: 35.7% (predicated anthropometrics from this website) would have a predicted RMR of ~3049 kcal, an increase of 959 kcal compared to my measly RMR value.
You may be wondering why Hafthor must consume 959 kcal more than me to maintain his bodily functions at rest, after all, we probably have similar physiologies in respect to brain and organ size. Well, it all comes down to FFM – something of which Hafthor slightly edges me on. FFM is a metabolically active tissue, meaning the more of it we have, the more kilocalories the body requires to maintain its function and movement. Assuming Halthor’s bf % is 35.7% and his weight is 180 kg, this means that his FFM is around 116 kg, whereas mine would be around 72 kg, a 44 kg difference of mostly muscle tissue!
RMR is the first calorie target that all strongman athletes should reach in order to maintain health and normal bodily function, and it’s a hefty one. For a strongman athlete to gain an accurate RMR value, a similarly accurate determination of bf % must be achieved unless they have the money to undertake an indirect calorimetry test. Bf % could be measured via skin callipers (ideally by an ISAK trained individual) but this is known to lead to validity errors of up to 10% in body fat. Other methods such as DXA scanning or air displacement plethysmography (BODPOD) may be more accurate but again, due to the body sizes of these athletes compared to the analysis compartments of these machines, testing may not be feasible. Regardless, indirect calorimetry or accurate body fat testing (albeit slightly inaccurate) should be considered for serious strongman athletes who wish to gain a better picture of their RMR and subsequent energy expenditure estimation.
A strongman athlete should also consider other components of energy expenditure which encompass their total daily energy expenditure (TDEE) – this will include dietary induced thermogenesis (DIT) and the thermic effect of exercise (TEE).
Eating Protein and Burning Calories? A Strongman Athlete’s Dream!
DIT refers to the increase in energy expenditure above RMR that occurs several hours following the consumption of a meal. DIT – in short – is the energy cost of metabolizing, absorbing, digesting, and storing various nutrients that come in differing sizes and compositions. DIT normally accounts for around 6 – 10% of TDEE, but can reach as low as 4% and as high as 15%. Because strongman athletes require sizable quantities of food, especially in the composition of dietary protein to allow for muscle maintenance, hypertrophy and recovery, they will more than likely be closer to the 15% mark than other athletes. This is because dietary protein is energy costly when consumed – meaning more kilocalories are required to ensure the metabolism, absorption, digestion, and storage of the ingested protein. DIT values are highest for protein (~15-30%), followed by CHO (~5-10%) and fat (~0-3%). As strongman athletes rely so heavily on dietary protein as a macronutrient, and do so in enormous quantities, they will generally have higher DIT values than the normal healthy person. This in turn is another reason why strongman athletes expend exceedingly high amounts of kilocalories.
Flippin’ Cars for the Kcals
The thermic effect of exercise (TEE) is the number of kilocalories required to perform work and is all the kilocalories expended above the RER and DIT. Work can be performed through both planned voluntary (exercise) and involuntary actions (shivering, fidgeting, postural control (also known as NEAT)) and therefore energy is required to be expended for all these components. In regards to the exercise component of TEE, there really isn’t any studies to suggest how many kilocalories may be expended during various strongman events. It becomes even more complicated to estimate these values as strongman events are often performed to failure, or in a horizontal plane whereby the athlete must move an X amount of weight over a certain distance. One study by Harris et al. (2016) measured the physiological responses of a strongman training session (sled drag at 200% BW for 12m, farmer’s walk at 80% BW in each hand for 24m, 1 arm dumbbell clean and press at 30% BW for 10 repetitions, and tire flip using a 220kg tractor tyre and performing repetitions within a 30s time frame) compared to a traditional exercise strength session (squat, deadlift, bench press, and power clean, progressing to 75% of 1 repetition maximum) and found that both sessions elicited similar physiological responses, with both also expending similar kilocalories over the respective session (8.9 and 9.1 kcal/min for the strongman and regular strength training session, respectively). Using this evidence, and assuming an average strongman athlete may perform their specialized session for 1 hour, they may expend around ~534 kcal/hr. This will obviously vary depending on the type of event performed, distance covered in events such as farmers walk and sled drags, as well as any additional cardiovascular work strongman athletes require to account for generally low VO2max values and potentially impaired cardiac relaxation.
Brian Shaw Ate 12,000 Calories, Should I?
When acquiring all the data surrounding TDEE in strongman athletes (RMR + DIT + TEE), it is clear that they will generally expend a hell of a lot of kilocalories, especially on training and competition days. Referring back to Hafthor, his TDEE may be in the range of 4510 kcal if he was to perform a 1-hour strongman session, 5000 steps, and eats a daily diet of 8,000 kcal (1000g CHO; 266g FAT; 400g PRO) over a 24 hour period. That’s just under 2.3 x higher than the daily reference kilocalories intakes of adults (2000 kcal).
If you are familiar with basic energy demands, then you will know that if energy intake matches TDEE, then we will achieve energy balance. Eating at an energy balance means that all the energy we expend over the day is equally replaced by consumed energy, allowing us to maintain a stable body weight and composition. If we have a negative energy balance (i.e energy intake is lower than energy expenditure) than we will lose body weight, and in severe energy deficits, may decrease FFM content). Conversely, if we have a positive energy balance (i.e energy intake is higher than energy expenditure), then we will gain body weight. A positive energy balance is often maintained by strongman athletes during off-season periods (whereby muscle hypertrophy Is the goal) and days leading up to competition to ensure optimal glycogen stores.
Using this information and referring to the knowledge that some professional strongman athlete’s energy intake is more than 8000 kcal, it may be immediately clear that these athletes are in an energy surplus. But is an 8000 kcal per day diet necessary for amateur to elite strongman athletes to increase muscle mass and improve performance? The answer is no (for the natural athlete). Strongman athletes such as Hafthor can put away 8000 kcal because of anabolic steroid use which drastically increases his RMR due to muscle mass gains (remember muscle is incredibly metabolically active!) and possible elevations to metabolic efficiency beyond that explained by changes to FFM. While 8000 kcal may be viable for many enhanced strongman athletes, it won’t be for others and may lead to increases in fat mass that may impact their performance and general health. For example, a greater bf % on a strongman athlete will increase the difficulty and energy demands during locomotive events like sled drags and farmers walk. It is therefore necessary for strongman athletes to eat relative to their training goals and TDEE to prevent excessive fat gain.
Off-Season Nutrition: Protein, Protein… and More Protein?
Talking of training goals, a strongman athlete may generally have 1 of 2 primary goals in the off-season – to increase muscle mass (thus increasing strength) or to decrease bf % (thus improving locomotive efficiency and general health outcomes).
If the goal is to increase muscle mass, then the aim is to apply an adequate training stimulus and energy surplus to maximise muscle protein synthesis. As a rule of thumb, to ensure that the body is in a state of anabolism whilst restricting the chances of fat mass accumulation, a strongman athlete should eat at 250-500 kcal above their estimated TDEE value. To further optimize muscle protein synthesis, dietary protein intake should be increased to between 1.6 – 1.7 g/kg BW with adequate consumption of readily-digestible, complete protein sources (especially ensuring optimal (> 3g) leucine content) and regular feedings of dietary protein across the day (usually 20-30g per meal and immediately post-exercise). Carbohydrate intake should also remain the majority energy source (~50% of total energy) and should be consumed to elevate insulin levels that, in effect, reduce protein breakdown and increase amino acid absorption in skeletal tissue which may subsequently improve muscle protein synthesis.
If the goal is to reduce bf % whilst slaving off those unwanted decrements to strength, then the aim should similarly be to maintain training load/stimulus at the same (or higher) intensity whilst applying a small energy deficit (~250 – 500 kcal) to your diet. To fully maximise the fat oxidative capacity of a strongman athlete, then they should look for ways which alter the various components of energy expenditure. For example, we now know that dietary protein intake is energy costly and requires more energy than any other macronutrient to metabolize. Not only is this true, but also elevated protein intakes will satiate the athlete better and reduce the incidence of muscle catabolism. It may therefore be worth a strongman athlete increasing the protein intake to 1.8 – 2g/kg BW under periods of caloric restriction.
Although a strongman should be incorporating aerobic-based exercise sessions into their weekly programme, it may be of increased benefit when trying to shed those extra pounds. Not only will this reduce any of the potential health concerns strongman athletes have known to possess (obstructive sleep apnea, elevated blood pressure, low cardiorespiratory fitness, increased plasma LDL, and reduced myocardial relaxation amongst others), but it will also help increase energy expenditure which, in effect, will lead to an energy deficit if energy intake remains the same. Professional strongman athlete, Drew Spriggs, wrote an article about his positive experiences with combining strongman training and cardiovascular training, which may be worth a read.
Nutrition and Supplements to Attenuate Muscle Damage: What the Hell Should I Take?
Due to the eccentric nature of strongman training, as well as the recruitment of large muscle groups to perform specific compound tasks, it is no surprise that strongman athletes may be severely impacted by exercise-induced muscle damage (EIMD) which could ultimately decrease their strength and power output. This is particularly unfavourable when performing multiple strongman-style events over a week – for example, the World’s Strongest Man took place over 3 days in 2019. The implementation of specific nutritional and supplemental strategies at pre/post-training/competition or in-between events may however augment and assist with the recovery process. Presently, many nutritional and supplemental strategies have been investigated to see which best inhibits EIMD, with varying results. Long-term consumption of antioxidant rich foods (i.e. tart cherry juice, pomegranate juice and beetroot juice) and chronic consumption of various supplements (I.e. creatine, omega-3 polyunsaturated fatty acids, and vitamin D3) may help attenuate EIMD, but the application of these foods or supplements into your diet should be first critically analysed by a performance nutritionist or dietician. For a brief review on nutritional / supplementation strategies to prevent and attenuate EIMD, please refer to the following review.
Nutrition and Supplements to Fuel Training and Competition: Eating to Win
Finally, we should really discuss how nutritional strategies could improve our performance during strongman activity or competition. As I have touched on previously, strongman events don’t just involve a series of isolated contractions that may be fuelled solely by adenosine triphosphate (ATP) and phosphocreatine (PCR) stores – alike powerlifting or Olympic weightlifting athletes. Rather, the requirement to perform resistance-type events over a horizontal plane tends to activate glycolysis to replenish depleted ATP. As a performance nutritionist, I am immediately drawn to the two energy systems which will be largely at play during strongman activity – ATP-PCR and glycolysis – and how we can optimize these stores prior to training or competition to perform efficiently.
The ATP-PCR system is the major energy producer for high-intensity exercise, however depletion of this energy source occurs within 5-10 seconds. One way to increase our energy stores of PCR is to supplement with creatine monohydrate or to consume foods rich in creatine content such as red meats and fish. When supplementing with creatine monohydrate, it is well known that 20 g / day for 5 consecutive days can increase intramuscular creatine stores by 20-30 mmol/kg d.m, followed by dosing of 2 – 3 g to maintain intramuscular concentration. Another more modest approach at creatine supplementation may be 2.5 g / day for 1 month that will evoke similar rises in intramuscular creatine stores. Nonetheless, creatine intake is essential for strongman athlete to fuel their fight against the immediate resistance placed upon their body.
If you’ve ever participated or watched strongman events before, then you will soon realize that they very rarely last for 5-10 seconds. Therefore, soon after 10 seconds has passed, glycogen become the main substrate utilized for this high-intensity exercise. It is therefore necessary for strongman athletes, prior to training or competition, to attain optimal muscle and liver glycogen stores. Replenishment of muscle glycogen stores can begin in the days prior to training or competition. Because strongman events (and generally, any additional resistance training completed on the side) will not completely eradicate muscle glycogen stores, strongman athletes should concentrate on eating a well-balanced diet, relatively rich in CHO, that may be in a slight calorie surplus rather than worrying about CHO loading – something of which is more often implemented in sports lasting over 30 minutes. In the hours (3-5 hrs) before training or competition, strongman athletes may want to consider eating a CHO rich meal (100 – 200g) which will replenish liver glycogen stores – which may be especially depleted from an overnight fast. Liver glycogen stores will most likely not be used in the immediate events, however if depletion of muscle glycogen stores was to occur over a whole days’ worth of events (which can occur during some competitions), then liver glycogen would be able to contribute to the maintenance of blood glucose during events later on in the day.
The lack of research conducted into these highly-elite athletes is rather concerning, and makes the job as a performance nutritionist particularly difficult, however deconstructing the basic components of strongman events allows us to determine a nutrition strategy that these athletes may benefit from.
If you are a strongman athlete looking to refine your performance, why don’t you consider my services so that together we can work to optimise your physical performance through nutrition. Please get in touch if you are interested.