Hyrox is a unique and challenging fitness race that combines functional fitness with endurance. The competition consists of eight different workouts, interspersed with 1-kilometer runs. Balancing energy intake to align to these training demands can be quite the challenge, but if done properly you’ll train harder and perform better.
Are You Eating Enough?
First things first, is to lay solid foundations by meeting your energy needs. If you are under eating whilst trying to push yourself to your physical and mental limits eventually something will give.
You may suffer performance plateaus, minor and recurring injuries that you keep trying to push and adapt your training to get through. Or significant injuries that lead to weeks, months out and a loss of all that hard work.
You need to be consuming enough calories to fuel your basic energy needs (your resting metabolic rate) and your training.
However on the flip if you meet your energy demands then you will enter and sustain performance in your session, adapt well from them and mentally you’ll be functioning on all cylinders.
What is you Resting Metabolic Rate?
Resting Metabolic Rate (RMR) is the amount of energy expended by the body at rest, excluding the active digestion of food. Essentially, it’s the energy required to maintain basic physiological functions such as breathing, circulating blood, and cellular growth. RMR makes up the largest portion of your total daily energy expenditure (TDEE), typically accounting for about 60-75%.
Failure to consume enough food to support both your RMR and Training will force your body into ‘energy saving mode’. This means it will utilise the energy from your RMR to fuel training. In time it will make you less metabolic efficient causing muscle turnover, bone health, hormonal functions (inc menstrual cycle in women), mental health to become compromised.
Knowing or having an estimate of your RMR helps in devising precise nutrition plans when you factor in how much exercise you are doing. Proper fuelling tailored to your body’s needs ensures sustained energy levels during training and recovery.
You can estimate it by using online calculators as a starting point or test it in a lab with indirect calorimetry. Remember these are just estimates to use as guides. It’s not advisable to get hooked on calories counting. As a simple rule, always listen to your body. If it’s asking for more, eat!
Mind Your Macros: It’s not energy in, energy out.
Your Macronutrients are carbohydrates, proteins and fats. Each have a variety of roles on the body and collectively contribute to energy levels, muscle repair and growth, and overall health.
Carbohydrates
Carbohydrates are the body’s primary source of energy. They break down into glucose, which is utilised by your cells, tissues, and organs. Our body only has a limited supply within the muscles and the liver.
So, if you don’t keep replenishing stores across each day and specifically around training you may suffer hypoglycaemia. This means you’ll feel sick, dizzy, light headed, jelly legs and have nothing left to give.
Carbohydrates are your most variable nutrient in terms of intake. For those doing 2-4 hour per week you may want to start at 4-5g/kg/bm (280g-350g for a 70gk person). For those pushing 10-12 hours or more this can increase to 8-10g/kg/bm and beyond depending on the type and durations of the sessions.
Other factors to consider is whether you’re a full time athlete, have a manual job, cycle to work, walk the dog etc. All these impact your intake and are often overlooked.
Carbohydrates can be found in foods such as potatoes, breads, fruits, vegetables, grains, and legumes.
As a simple rule, always listen to your body.
If it’s asking for more, eat!
Protein
Adequate protein intake is critical for muscle repair, growth, and overall recovery.
Typically, endurance athletes should be consuming between 1.2-1.6 gram per kilogram per body mass (84-112g protein for a 70kg person).
Power athletes 1.6-2.0g/kg/bm and up to 2.4g/kg/bm more is targeting muscle gains or weight loss. So it’s easy to see how it can be confusing for someone training for both endurance and power.
Given the nature of the training aiming for the 1.6-2.0g/kg/bm bracket is a good start. You can increase or reduce depending on your training and goals.
The fitness culture is very protein orientated and it is often over hyped. This can lead to people over consuming protein in favour of carbohydrates and even fats.
More of something isn’t necessarily better! Too much protein can cause insufficient intakes of the nutrients required to support fuelling, hormone and brain health to name a few. It’s always worth taking a step back and recalibrating to ensure you have the balance right.
Protein sources include meat, fish, dairy products, legumes, and plant-based options like tofu and quinoa. Preferring plant based protein options is not a barriers to hitting those targets.
Fats
Though often demonized, dietary fats are crucial for overall health and athletic performance. Fats are the most energy-dense macronutrient and are essential for the absorption of fat-soluble vitamins (A, D, E, and K).
Intake can usually range between 1.0-1.5g/kg/bm, but this will vary depending on your carb and protein intake. It’s typically the last thing to calculate to hit your energy needs.
Common sources of healthy fats include avocados, nuts, seeds, olives, olive oil and oily fish like salmon and mackerel.
Micronutrients: Don’t forget the little guys.
The importance of micronutrients shouldn’t be underestimated. These essential vitamins and minerals play crucial roles in a myriad of bodily functions, from energy production to muscle contractions, bone metabolism and immunity to say a few.
As a simple strategy you want to incorporate the full spectrum of colours (green, red, yellow, purple, blues, orange, white) into your meals and snacks. Each colour has a different role and health benefit. Try and aim for 2-3 colours in every meal. Smoothies and utilising fruits as part of your fuelling strategy can help achieve this.
Some of the Essential Micros
Some key micronutrients we put a lot of emphasis on for athletes are iron, calcium, vitamin D and magnesium.
There aren’t any athlete specific recommended intakes for these vitamins and minerals, those provided are from The UK National Health Service (NHS). However, we can assume the more you training the greater the demand, a as your total energy intake will be greater then naturally you should be consuming more of each nutrient assuming your diet is balanced.
Should you omit any food group from your diet it’s always advisable to seek medical advise as supplementation my be required.
Iron:
Iron is a mineral required for the production of haemoglobin, a protein in red blood cells that carries oxygen throughout the body.
Deficiency can lead to anaemia, characterised by fatigue, weakness, and decreased performance. Those most prone to iron deficiency are women with heavy menstrual cycles, vegetarians, vegans and endurance athletes as blood can be lost through the feet due to the impact of running (foot strike haemolysis).
Ensuring adequate iron levels can enhance endurance, energy levels, and recovery time.
Recommended Intake: 8.7 mg (men), 14.8 mg (women)
General Guidance: Aim for 2-3 servings red meat per week. Supplementation may be required for vegetarians, vegans women with heavy menstrual cycles, endurance athletes and those who choose to omit red meat. Please seek medical guidance before supplementation.
Iron-rich foods include red meat, poultry, seafood, beans, dark leafy greens, and iron-fortified cereals. Vegetarians can rely on plant-based sources like lentils, spinach, and fortified cereals, but they should be aware that plant-based iron (non-heme iron) is less easily absorbed than the iron from animal products (heme iron), so pairing these with vitamin C-rich foods can boost absorption.
Calcium:
Calcium is a vital mineral found predominantly in bones and teeth, playing a key role in maintaining their structure and strength.
Adequate calcium intake helps prevent stress fractures and strengthens the skeletal system. Additionally, calcium is necessary for muscle contraction, which directly impacts athletic performance and we can also lose calcium in sweat.
During high long sweat session including calcium foods as part of your fuelling strategy can increase serum calcium levels and help maintain bone health.
Recommended Intake: 700 mg for both men and women.
General guidance: Aim for 3 servings of dairy per day.
Dairy products like milk, cheese, and yogurt are excellent sources of calcium. For those who are lactose intolerant or vegan, leafy greens (kale, broccoli), fortified plant milks, and almonds are good alternatives.
Vitamin D:
Vitamin D, also known as the sunshine vitamin, is crucial for bone health as it enhances calcium absorption in the gut. It also impacts immune function, muscle health, and inflammation regulation. Deficiency can lead to weaker bones and increased risk of fractures and infections.
In the UK we only have the correct UVB rays to synthesis vitamin D 6 months of the year; between April-October, During this time 10-15 minutes sun exposure on the arms and face will be sufficient. During the winter months, November-March supplementation may be required if not seeking winter sun abroad. In this instances and in absence of a test 1000-2000IU per day is advised.
Magnesium:
Magnesium is critical for muscle function and recovery. It helps in muscle contraction and relaxation, reducing cramps and muscle soreness post-training. It also plays a role in converting food into energy, essential for endurance athletes to sustain long periods of exertion.
Recommended NHS Intakes: 300 mg (men), 270 mg (women)
Magnesium-rich foods include nuts (almonds, cashews), seeds (pumpkin, flax), whole grains, and leafy green vegetables. Incorporating these into your daily diet can help meet the recommended intake.
Fibre: An Often Overlooked Nutrient
Although fibre is not a micronutrient, it’s indispensable for overall health and optimal athletic performance. Diets rich in fibre aid in gastrointestinal health, help maintain stable blood glucose levels, and contribute to overall dietary balance, which supports athletic performance.
According to the NHS, adults should aim to consume 30 grams of fibre per day although some advice relative to intake recommends 15g per 1000kcal. Including a variety of fibre-rich foods like fruits, vegetables, whole grains, and legumes can help achieve this target.
Summary
Meeting your energy needs is the main foundation to your health and performance.
Assessing and understanding what they are might just be what you need to propel you to the next level of your training.
Balancing your macros and ensuring you’re not deficient in any micronutrients will set you up to achieve your goals.
You can then channel this into your fuelling strategy and propel yourself towards your goals.
