F1 is heating up
“They only have to drive a car” as I answer questions to what we do to prepare drivers to race. Similar to neck strength, an overlooked area of driver fitness is the ability to perform in considerably hot conditions.
Although I imagine slightly more understood by many after the 2018 London Marathon recorded its hottest temperature ever at 24.1°C. Of the 41,003 runners who started the race, 748 didn’t cross the finish line and unfortunately over 100 were admitted to hospital in a serious condition (Evening Standard). It was hot! And at that temperature you lose approximately 10 secs of speed per kilometre, or 7 minutes across marathon distance, 7 minutes of physical reduction in performance without considering any mental component.
We unfortunately don’t have any concrete data on cockpit temperature in F1, but estimates for the Singapore Grand Prix place the ambient temperature at approximately 40°C and the cockpit temperature at up to 50°C! (Motorsport Technology). The Malaysian Grand Prix, which is rumoured to maybe making an appearance again sooner rather than later is similar measuring 49°C trackside.
Data from closed cockpit races show in race involving V8 supercars, the cockpit temperature can reach 52.1°C. Anecdotal evidence in NASCAR suggests up to 54.4°C (Ferguson, 2019). More than double that of those experienced during that 2018 London marathon. F1 has the obvious advantage of an open cockpit and on a fast straight this is very welcomed by the drivers, however a very technical circuit like Singapore does not allow for this.
A lot of the heat impacting an F1 driver is due to the stored heat produced by the kit requirements. A driver will wear fire-retardant long sleeved under top and trousers, long fire-retardant socks, balaclava, full race suit, shoes and gloves, and a full face helmet. Each layer having it’s own individual layers to provide the fire resistance needed and creating micro-climates which store heat and leaving little exposure to the outside climate for heat exchange to take place (Ferguson, 2019. The driver will then jump into the cockpit of the car which creates another micro-climate of heat and reduced exposure, mixed in with some hot races and we have an environment that may become problematic for a driver. However, better to be safe and then implement the right strategies to aid the rest!
The physical and mental effects on the body and mind to perform under this heat could potentially be catastrophic and season defining. The normal core body temperature is 37°C and generally ranges from 36.5 to 37.5°C depending on where you read. It is a highly regulated system and does not vary from a few degrees, Astrand et al (2003) commenting “we live only a few degrees from death”. The development of hyperthermia which is a series of heat related conditions occurs when the core body temperature increases to 38.5°C and above (Periard et al, 2013). Such increases in the core temperature under heat stress have been shown to induce fatigue and impair performance as well as placing increased physiological demand on our vital organs.
When we look to motorsport, Brearly and Finn (2007) found a peak post race core temperature of 39.7°C in V8 Supercar drivers and Carlson et al (2014) a peak post race core temperature of 38.6°C in NASCAR drivers, placing these drivers in a “at risk” category. It also does not take long to meet these temperatures, Potkanowicz (2015) found in a closed cockpit 20 minute race drivers were half way to their peak temperature at 10 minutes. Interestingly he also found that it started to spike prior to getting into the cars.
Although all closed cockpit data, we can presume given the construction an F1 car that although drivers will experience some nice air around the torso and neck on straight sections of a circuit the majority of the time will be spent in similar temperatures for 1.5-2 hours. This means a large degree of physical stress for a prolonged period which will result in a significant reduction in performance (Periard et al, 2013).
When exercising, driving or performing in the heat, skin blood flow and sweat rate increase to allow for heat dissipation to the surrounding area. These thermoregulatory adjustments although extremely efficient increase the physiological strain on the body. To further complicate the issue this is not efficient in drivers given their protective attire. They cannot cool as they are fully covered, leading to increases in heart rate to increase cardiac output and a redirection of blood from the organs to try and provide adequate blood slow for thermoregulation. Ladells (1957) suggested that an increase in core temperature of 1°C could increase heart rate by 25bpm. This creates whats called a cardiac drift and can lead to early fatigue (Galloway and Maughen 1997) and performance deficits.
Astrand et al (2003, cited from Ferguson, 2019) suggests that someone who is acclimatised to heat will experience a drop in mental capacity at 30°C of room temperature (cockpit temperature). If they are unacclimatised this will occur at 25°C. These drops in performance include a deterioration in dexterity, coordination, ability to remain alert and ability to process and make quick decisions. All skills that are extremely vital for an F1 driver whether that’s the dexterity to press the buttons on the steering wheel or a decision on a line of overtake it could and make or break a race result or potential collision.
As a result of the reduced heat dissipation via convection, sweat evaporation then becomes a primary avenue for cooling. This increase reliance on evaporative heat loss means hydration becomes a significant role in maintaining thermal homeostasis as excessive dehydration will exacerbate hyperthermia. Brearly and Finn (2007) found that drivers in the V8 supercars have a sweat rate of up to 1.18 litres per hour. Given an F1 car only holds 1.2 litres of fluid, in a race that takes 2 hours, such as Singapore, drivers will be losing double what they can replace. This will equate to driver losing approximately 3kg of body weight over a hot course (or 1/2 stone) (Ferguson et al, 2018).
With so much at stakes it is important drivers and their teams do everything they can to reduce the impact of over heating and the negative performance implications which it brings. Although we don’t have a lot of research in F1, there are some good studies and consensus on how to best prepare for the heat with many of our world sporting events such as the football world cup and olympics taking part in the summer months.
The most important intervention to reduce the physiological strain and optimise performance is to heat acclimatise. Heat acclimatisation will lower the physiological strain for competition and improve their exercise capacity. It should comprise repeated exercise-heat exposures over 1-2 weeks leading to competition (Racinais et al, 2015). This should be in the same environment as the competition, if not mimicked as best you can. The latter which is completed in F1 due to the limitations of testing in the car. Therefore use of hot rooms, saunas, clothing in warm weather can be utilised to create various micro-climates. Regular exercise in temperate conditions can elicit a partial heat acclimatisation but it cannot replace consecutive days training in heat (Armstrong and Pandolf, 1988). Most adaptations take place in the first week of heat acclimatisation and more slowly in the second week, with highly trained athletes developing more quickly.
The amount of acclimatisation depends on adaptation of training principles: intensity, duration, frequency, and number of heat exposures. This comes down to training for what you are trying to achieve. In F1 this will require a mixture of low level long duration training mixed in with some high intensity sessions. One study found similar physiological adaptions from 30-35 mins at 70% VO2max and 60 mins at 50% VO2max with the aim to increase body core and skin temperature and stimulate sweating. The majority of really stressful races are in hit humid conditions so the aim would be to try and find or create an environment to mimick this.
The second most important controllable factor is hydration. If a driver falls into a dehydrated state then we get increased heat storage and increased strain on the cardiovascular system. Drivers are going to lose 1.5-2.5 litres of fluid per hot race and with us only able to store 1.2 litres in the car pre and post hydration are very important. The past suggestions have been that we should drink to thirst, however this could already leave us in a deficit and would not be effective in this scenario. Therefore it is important that drivers enter race weekend and race day in an euhydrated state. Advice from Racinais et al’s consensus statement is to consume 6ml of water per kg of body mass during this period every 2-3 hours, as well as 2-3 hours prior to training or competition in the heat. We monitor this using an osmocheck. Due to sweat rates, the loss of sodium and increased carbohydrate metabolism in the heat, we will also utilise electrolyte tablets before, during and after as well as a carbohydrate mix alongside a good healthy pre race diet.
Post race is similar and we will try to replenish the body’s fluid loss as quickly as possible with the recommendation being 100-120% of body mass losses in the first hour, alongside sodium, carbohydrate and protein supplementation either via food or a protein based drink. This can be difficult in F1, particularly if the driver has had a podium finish as all drivers post race head off to the FIA garage to be weighed and then those that finish on the podium have the podium celebrations, so getting as much in, in a short space of time is important.
Finally, we will utilise some cooling strategies. This is difficult on race day as there is no stoppages but during practice and qualifying when the car comes in, a drivers trainer will hold a fan into the cockpit to cool their driver down, as well as passing them a drink, likely with a electrolyte / carbohydrate mix and ice. After the race the first thing a driver’s trainer may pass the driver is a cold, wet towel or a cooling vest to help bringing their body temperature down. If we can cool the body it allows for greater heat exchange with the outside environment.
Each driver will have there own preferred methods that have been tried and tested and work for them, however within this there will need to be consideration for heat acclimatisation, hydration and cooling to enable them to perform at their best without the associated reductions in physical and mental performance.