Physiological responses to high-speed, open-wheel racecar driving

An ecological and embodied approach for training the racecar driver

In the dynamic sport of racecar driving, split-second decisions and rapid execution are imperative. Such an environment requires a tight functional coupling of perception and action. This paper introduces an approach for training racecar drivers rooted in ecological and embodied perspectives. It discusses three pivotal affordances of racecar driving: turn-ability, overtake-ability, and defend-ability. The paper also discusses the relevant environment and equipment (i.e., simulators) that can be useful for training racecar drivers. In addition, practice activities relevant for the actual racetrack or to the simulator are discussed. Coaches are encouraged to try and implement the proposed training strategies (or parts of it), evaluating their impact on racing performance. Furthermore, researchers can continue exploring these principles, fostering a fusion of empirical insights with practical expertise from coaches and racing communities. By synergizing empirical research with insights from practitioners, we can refine the strategies employed in the training of racecar drivers.

Application of a Reactive Agility Training Program Using Light-Based Stimuli to Enhance the Physical and Cognitive Performance of Car Racing Drivers: A Randomized Controlled Trial

BACKGROUND

There is a need to develop strategies that could contribute to the physical and mental preparation of motorsport athletes. A common method used by experienced motorsport athlete physical trainers is flashing light devices to train or assess reactive agility, despite limited evidence. Therefore, in the present study, we determined the effects of a 6-week reactive agility training program using light-based stimuli on the physiological and cognitive abilities of car racing drivers.

MATERIALS AND METHODS

The CONSORT guidelines for randomized controlled trial were used. In a single-blinded randomized controlled trial, 24 car racing drivers (EXP, n = 12; CON, n = 12) performed a comprehensive battery of cognitive tests marketed specifically at motorsport athletes from Vienna test system (VTS) at rest or during moderate intensity exercise on a bicycle. Physiological abilities were determined via a maximal incremental cardio-respiratory treadmill test. Baseline and post-intervention tests were performed on three consecutive days. Participants in EXP underwent a 6-week intervention consisting of 60-min training sessions twice a week using the Witty SEM light stimulus.

RESULTS

Participants in EXP but not in CON performed some of the VTS cognitive tasks with higher accuracy and/or shorter reaction time after the intervention at rest and during exercise. Car racing drivers performed the STROOP word-reading condition more accurately when the task was performed during the exercise vs. rest, regardless of group. In addition, the intervention induced beneficial changes in peak heart rate (HR), HR at gas exchange threshold, ventilation, and relative maximal oxygen consumption (rVO₂ max). In contrast, body mass and fat mass increased, while peak HR and rVO₂ max decreased in CON. Finally, participants in EXP improved their reactive agility performance and reaction time throughout the training program.

CONCLUSION

Overall, the reactive agility training program using light-based stimuli appeared to be efficient to induce beneficial effects on some physiological and cognitive performance measures; therefore, it may have the potential to contribute to car racing drivers' physical and mental performance.

Redox Implications of Extreme Task Performance: The Case in Driver Athletes

Redox homeostasis and redox-mediated signaling mechanisms are fundamental elements of human biology. Physiological levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS) modulate a range of functional processes at the cellular, tissue, and systemic levels in healthy humans. Conversely, excess ROS or RNS activity can disrupt function, impairing the performance of daily activities. This article analyzes the impact of redox mechanisms on extreme task performance. Such activities (a) require complex motor skills, (b) are physically demanding, (c) are performed in an extreme environment, (d) require high-level executive function, and (e) pose an imminent risk of injury or death. The current analysis utilizes race car driving as a representative example. The physiological challenges of this extreme task include physical exertion, g loading, vibration, heat exposure, dehydration, noise, mental demands, and emotional factors. Each of these challenges stimulates ROS signaling, RNS signaling, or both, alters redox homeostasis, and exerts pro-oxidant effects at either the tissue or systemic levels. These redox mechanisms appear to promote physiological stress during race car driving and impair the performance of driver athletes.

Relationship between pre-driving heart rate and driving performance in formula car racing: a case study

Formula car racing is highly competitive and induces significant physical stress. Previous studies have shown that intense physical stresses, such as g-force, accelerate the driver's heart rate (HR). In contrast, it remains unclear whether psychological stress affects the physiological states of racers and racing performance. To investigate this phenomenon, we developed a wearable monitor that can track the driver's HR during a race. The HR and driving performance of two professional drivers were monitored in real racing situations. Changes in HR were then evaluated based on changes in the racing situation and car behavior. The results suggest that HR acceleration is strongly correlated with race situations such as free practice or qualifying sessions, and that such changes are related to subsequent driving performance.

Responses of Driver-Athletes to Repeated Driving Stints

PURPOSE

The purpose of this study was to examine and quantify the effect of repeated driving stints on the physiologic, metabolic, and hormonal responses of three professional endurance driver-athletes.

METHODS

Core body temperature, HR, and physiological strain index were recorded during the Rolex 24 Hours of Daytona endurance race using the Equivital Life Monitor system. Blood glucose was monitored continuously during the event using a FreeStyle Libre Pro (Abbott, Alameda, CA). Alpha-amylase and cortisol were sampled immediately before the beginning of a stint and immediately after.

RESULTS

First-stint overall and individual driver-athlete responses were similar to those reported in the literature. Later-stint responses diverged from the literature. Reductions in initial core temperature, absence of increases in HR and physiological strain index, and altered glucose and hormonal responses were each observed in the later stint.

CONCLUSION

The data support previous research showing that motorsports has a measurable physiological, metabolic, and hormonal effect on the driver-athlete. This study also shows that multiple stints elicit responses that deviate from the published literature on single-stint events. This study is also particularly interesting in that it represents one of the first times that longitudinal data have been gathered on endurance racing driver-athletes.

Cockpit Temperature as an Indicator of Thermal Strain in Sports Car Competition

PURPOSE

This study aimed to evaluate the relationship between race car cockpit temperature and thermal strain indicators among race car drivers.

METHODS

Four male racing drivers' heart rate (HR), skin temperature (Tskin), and core temperature (Tcore) were measured continuously using the Equivital Life Monitor bio harness, and physiological strain index (PSI) was calculated during a hot (ambient temperature of 34.1°C ± 2.8°C) 6-h endurance race. Only data collected during green flag racing laps were analyzed.

RESULTS

Cross-sectional analyses showed that cockpit temperature did not have a significant relationship with percent of HRmax, Tskin, Tcore, or PSI (P > 0.05) during the race. Cockpit temperature decreased during driving time, whereas percent of HRmax, Tskin, Tcore, and PSI increased (P < 0.05).

CONCLUSION

Cockpit temperature does not correlate with measures of race car driver thermal strain. Therefore, metrics to determine driver thermal strain should include direct monitoring of the race car driver.

Advantage and use of S-patch cardio solution in competitive motor sports

BACKGROUND

Motorsport karting has developed into a professional international competition. Kart racing poses a unique set of physiologic challenges for athletes who compete in this sport. Until today no major study has evaluated the physical and cardiac challenge in professional kart racing.

OBJECTIVE

The aim for this study was to measure and analyze heart rate and cardiac rhythm by a mobile, smartphone based ECG (s-patch) on professional kart-race-drivers during actual karting races through annual seasons to test the hypotheses that high g-force and stress could trigger cardiac arrhythmia.

MATERIAL AND METHODS

ECG-data from kart-drivers were acquired during local races, the ADAC Kart-Masters (KZ2), the German Kart Championship (DSKC) and the European Championship Senior CIK-FIA-Serie and analyzed in this observational study. In total, free practice, qualifying practice and 32 races were assessed during the kart season 2019. Data were interpreted by two independent experienced physicians.

RESULTS

The average heart rate (HR) during a selected German Kart Championship (DSKC) race in Genk (Belgium) was 169 beats min-1. The longest R-R interval was 0.72 sec. The average HR during a selected European Championship CIK-FIA-race in Lonato (Italy) was 160 beats min-1. The longest R-R interval was 0.74 sec. The average HR during a selected ADAC Kart-Masters (KZ2) races in Wackersdorf (Germany) was 147 beats min-1. The longest R-R interval was 0.86 sec. In total 32 races could be recorded successful. No couplets or bigeminy cycles were detected. In one other kart racer a supraventricular extrasystole and a ventricular extrasystole was detected. Interestingly, kart-drivers were found to have sinustachycardia throughout the races most likely triggered by emotional and physiological stress during speeding.

CONCLUSION

Professional kart racing drivers had sinustachycardia with heart rates up to 193 beats min-1 during races. This is most likely attributed to a considerably high emotional and physiological stress affecting the cardiovascular system. Episodes of tachycardia positively correlated with mean speed. In the warm-up lap the heart rate was significantly lower in comparison to the race, suggesting that faster driving speed would induce greater cardiovascular stress to professional drivers during actual races. The experimental results showed that the proposed S-patch system provided a good ECG signal quality with accurate measurements even during the kart race and could detect the ECG features of the race in real time. The cardiac interpretation software performs well and is a useful tool to assist clinicians.

The Physiology of Auto Racing

INTRODUCTION

Auto racing poses a unique set of physiologic challenges for athletes who compete in this sport. These challenges are not widely recognized due to the limited amount of original research in this field and the diffuse nature of this literature. The purpose of this article is to review the major physiologic challenges of auto racing and summarize what is currently known about athletes in this sport.

CONCLUSIONS

The physical stressors of either driving or servicing the race car are overlaid with particular environmental challenges associated with racing (e.g., thermal, noise, carbon monoxide exposure) that increase the physiological stress on motorsport athletes. Physical stress reflects the muscular work required for car control and control of posture during high gravitational (g) loads: factors that predispose athletes to fatigue. The physiologic effects of these stressors include cardiovascular stress as reflected by prolonged elevation of heart rate, cardiac output, and oxygen consumption in both driver and pit athletes during competition. Psychological stress is evident in autonomic and endocrine responses of athletes during competition. The thermal stress of having to compete wearing multilayer fire suits and closed helmets in ambient temperatures of 50°C to 60°C results in the ubiquitous risk of dehydration. Published data show that both drivers and pit crew members are accomplished athletes with distinct challenges and abilities. There are gaps in the literature, especially in regard to female, older adult, and child participants. Additionally, minimal literature is available on appropriate training programs to offset the physiological challenges of auto racing.

Physiological Responses of Male and Female Race Car Drivers during Competition

Automobile racing is one of the largest spectator sports in the world with male and female drivers competing together. Popular media has speculated on the relative capabilities of males and females in automobile racing, yet there are no scientific investigations examining physiological responses to racing among males and females.

PURPOSE

1) To evaluate the physiological responses of male and female drivers in open and closed cockpit race cars, 2) to examine the moderating influence of menstrual cycle phase on physiological responses to racing among female drivers.

METHODS

HR, breathing rate, skin temperature, core temperature, and Physiological Strain Index (PSI) were measured using the Equivital Life Monitor in male (n = 6) and female (n = 6) drivers at three races in open or closed cockpit cars. Among females, menstrual cycle phase for each race was recorded.

RESULTS

During racing conditions there was no difference (P > 0.05) between male and female drivers for HR, skin temperature, core temperature, or PSI. The female drivers had a higher (P < 0.001) breathing rate compared with the male drivers. Compared with the follicular phase, the luteal phase had an increased (P < 0.001) HR, breathing rate, skin temperature, core temperature, and PSI. The closed cockpit cars elicited (P < 0.001) a higher skin temperature, core temperature and PSI as compared with the open cockpit cars.

CONCLUSIONS

There were no differences in the physiological responses to automobile racing between male and female drivers. The luteal phase elicited higher physiological responses than the follicular phase, but was not different from the male drivers. Thereby, practitioners should focus on reducing stresses induced by a closed cockpit race car as opposed to the menstrual cycle.

V˙O2peak, Body Composition, and Neck Strength of Elite Motor Racing Drivers

PURPOSE

Automobile racing is widely known to be physically demanding; however, there is no published information comparing the physical fitness variables of elite-level race car drivers across various competitive championships.

METHODS

We documented the body composition, peak oxygen consumption (V˙O2peak), and isometric neck strength in a sample of elite race car drivers currently competing in Formula 1, IndyCar, NASCAR, and International Motor Sports Association sports car racing (IMSA GTD), to determine current human performance benchmarks and establish goals for drivers wishing to compete in these series.

RESULTS

Percent body fat was significantly (P < 0.001) lower in Formula 1 drivers (8.1% ± 1.7%) as compared with the other series, with IndyCar (17.4% ± 1.7%) and NASCAR (17.3% ± 4.6%) being less than IMSA GTD (24.9% ± 1.8%). Percent lean mass followed the same trend as percent body fat. IMSA GTD had not only the highest percent body fat but also the lowest (P = 0.001) V˙O2peak (45.2 ± 2.1 mL·kg·mL) compared with Formula 1 (62.0 ± 6.0 mL·kg·mL), IndyCar (58.05 ± 6.40 mL·kg·mL), and NASCAR (53.2 ± 4.1 mL·kg·mL). Isometric neck strength was the highest in Formula 1 and IndyCar drivers as compared with IMSA GTD and NASCAR drivers.

CONCLUSION

These results support the hypothesis that the varying physical demands of each competition series require different physical fitness levels of drivers. These benchmarks can be used by exercise professionals to better prepare athletes for competition.

Assessment of Dietary Intake of Long-Distance Race Car Drivers—A Pilot Study

Long-distance race car drivers are classified as athletes. The sport is physically and mentally demanding, requiring long hours of practice. Therefore, optimal dietary intake is essential for health and performance of the athlete. The aim of the study was to evaluate dietary intake and to compare the data with dietary recommendations for athletes and for the general adult population according to the German Nutrition Society (DGE). A 24-h dietary recall during a competition preparation phase was obtained from 16 male race car drivers (28.3 ± 6.1 years, body mass index (BMI) of 22.9 ± 2.3 kg/m²). The mean intake of energy, nutrients, water and alcohol was recorded. The mean energy, vitamin B₂, vitamin E, folate, fiber, calcium, water and alcohol intake were 2124 ± 814 kcal/day, 1.3 ± 0.5 mg/day, 12.5 ± 9.5 mg/day, 231.0 ± 90.9 ug/day, 21.4 ± 9.4 g/day, 1104 ± 764 mg/day, 3309 ± 1522 mL/day and 0.8 ± 2.5 mL/day respectively. Our study indicated that many of the nutrients studied, including energy and carbohydrate, were below the recommended dietary intake for both athletes and the DGE.

Physical Fitness and Blood Glucose Influence Performance in IndyCar Racing

Ferguson, DP and Myers, ND. Physical fitness and blood glucose influence performance in IndyCar racing. J Strength Cond Res 32(11): 3193-3206, 2018-Charlie Kimball (CK) is an elite-level IndyCar driver who has type 1 diabetes. Since CK became a full-time competitor, there has been exponential growth in the number of racing drivers competing with type 1 diabetes. Therefore, the purpose of this article is to present a case report of data collected on CK over 6 years, to better inform strength and conditioning coaches on how to prepare racing drivers with type 1 diabetes for competition. We hypothesized that the physical requirements to pilot the race car would include an elevated aerobic and glycolytic capacity and that blood glucose would influence key driving parameters (vertical gravitational force [Gz] tolerance and reaction time/response accuracy) related to success (finishing position). Physical fitness was evaluated with a V[Combining Dot Above]O2max test, dual-energy X-ray absorptiometry body composition analysis, Wingate power test, and a lower-body negative pressure test for vertical Gz tolerance. To test the role of fitness and blood glucose on driving performance, heart rate (HR), breath rate (BR), and skin temperature (ST) were evaluated during practice racing sessions using the Equivital Life Monitor. Blood glucose was monitored in 47 races using a continuous glucose monitor. Driving a race car resulted in increased HR, BR, and ST. The driver's body composition, skeletal muscle power output, and aerobic capacity values were in the 10th percentile of the average population. A blood glucose range of 100-168 mg·dl was identified as optimal for driving performance for the case study participant because it improved reaction time/response accuracy and Gz tolerance.

The Racer's Mind-How Core Perceptual-Cognitive Expertise Is Reflected in Deliberate Practice Procedures in Professional Motorsport

The exceptional performance of elite practitioners in domains like sports or chess is not a reflection of just exceptional general cognitive ability or innate sensorimotor superiority. Decades of research on expert performance has consistently shown that experts in all fields go to extraordinary lengths to acquire their perceptual-cognitive and motor abilities. Deliberate Practice (DP) refers to special (sub)tasks that are designed to give immediate and accurate feedback and performed repetitively with the explicit goal of improving performance. DP is generally agreed to be one of the key ingredients in acquisition of expertise (not necessarily the only one). Analyzing in detail the specific aspects of performance targeted by DP procedures may shed light on the underlying cognitive processes that support expert performance. Document analysis of professional coaching literature is one knowledge elicitation method that can be used in the early phases of inquiry to glean domain information about the skills experts in a field are required to develop. In this study this approach is applied to the domain of motor racing - specifically the perceptual-cognitive expertise enabling high-speed curve negotiation. A systematic review procedure is used to establish a corpus of texts covering the entire 60 years of professional motorsport textbooks. Descriptions of specific training procedures (that can be unambiguously interpreted as DP procedures) are extracted, and then analyzed within the hierarchical task analysis framework driver modeling. Hypotheses about the underlying cognitive processes are developed on the basis of this material. In the traditional psychological literature, steering and longitudinal control are typically considered “simple” reactive tracking tasks (model-free feedback control). The present findings suggest that—as in other forms expertise—expert level driving skill is in fact dependent on vast body of knowledge, and driven by top-down information. The knowledge elicitation in this study represents a first step toward a deeper psychological understanding of the complex cognitive underpinnings of expert performance in this domain.

Hydration Status and Thermoregulatory Responses in Drivers During Competitive Racing

Carlson, LA, Lawrence, MA, and Kenefick, RW. Hydration status and thermoregulatory responses in drivers during competitive racing. J Strength Cond Res 32(7): 2061-2065, 2018-Stock car drivers are exposed to high ambient temperatures, further complicated by the fact that they are encapsulated in protective clothing; however, the hydration status of these drivers has not been determined. This study quantified the degree of fluid losses during a competitive event in hot conditions. Nine male stock car drivers (29.6 ± 9.4 years, 177.8 ± 3.0 cm, 81.5 ± 18.5 kg) were studied during a Pro Series Division NASCAR race. Sweat rate (SR) and dehydration was determined through nude body weights (BWs). Prerace BW was 81.5 ± 18.5 kg and decreased to 81.1 ± 18.5 kg after race (p = 0.001). Body weight loss after race was 0.77 ± 0.3% and mean SR was 0.63 ± 0.4 L·h. Intestinal core temperature increased from 38.0 ± 0.4 to 38.5 ± 0.4° C after race (p = 0.001). Skin temperature increased from 35.8 ± 0.8 to 36.9 ± 0.8° C after race (p = 0.001), whereas the core-to-skin temperature gradient narrowed from 2.2 ± 0.9 to 1.6 ± 0.9° C, before race to after race (p = 0.001). Heart rates after race were 89 ± 0.0% of the drivers' age-predicted maximum heart rate (HR). Fluid losses during competitive racing can be significant. Without a fluid replacement strategy, fluid losses may exceed 3% of BW and could negatively impact driving performance in longer races.

Speed ratio but cabin temperature positively correlated with increased heart rates among professional drivers during car races

OBJECTIVES

The present study measures heart rate (HR) on a number of professional race-car drivers during actual car races through annual seasons to test hypotheses that faster relative speed and higher cabin temperature would induce higher HR.

METHODS

Heart rates in fifteen male drivers (31.2 ± 5.5 years old) were obtained by chest-strap sensors during official-professional 13 races. Average HR was calculated while the driver was racing from the start to the end of each race.

RESULTS

The average HR during races was 164.5 ± 15.1 beats min-1 and the average amount of time each driver spent driving per race was 54.2 ± 13.7 min. Average HR significantly and positively correlated with mean speed ratio (P < 0.001), but not with the average cabin temperatures (P = 0.533, range 25.6-41.8 °C) by the multiple linear regression analysis. Both average HR and mean speed ratio were significantly lower under wet, than dry conditions (151.9 ± 16.5 vs. 168.3 ± 12.5 beats min-1, 86.9 ± 4.4 vs. 93.4 ± 1.5 %).

CONCLUSIONS

The cardiovascular system of drivers is considerably stressed at extremely high HR. This high average HR positively correlated with mean speed ratio, suggesting that faster driving speed would induce greater cardiovascular stress to professional drivers during actual races. However, contrary to our hypothesis, cabin temperature was not significantly correlated with average HR. It is speculated that direct body cooling systems used in this professional race category work well against increases in HR by thermal stress under the temperature range found herein.

Stress Markers During a Rally Car Competition

The aim of the study was to assess the stress responses in drivers during an official rally car race and the influence of fitness and body composition on stress hormones. Fitness and body composition were assessed in 9 rally car drivers with an incremental exercise test for determination of maximum aerobic speed (MAS) and 6-site skinfold method, respectively. Before (pre) and after (post) the first stage of an official rally car race, data were collected for heart rate (HR), blood samples were collected for analysis of hormones (i.e., epinephrine [EPI], norepinephrine [NE], cortisol, and aldosterone) and metabolites (i.e., lactate [LA], glucose, and ammonia). There were significant (p ≤ 0.05) increases in all assessed variables except glucose at postrace. Heart rate increased 93% (p ≤ 0.05) at the end of the race stage, reaching 88.77 ± 4.96% of HRpeak. Also, EPI and NE significantly (p = 0.001) increased by 45 and 65%, respectively, and LA increased by 395% (p < 0.001). Significant correlations between percent body fat (%BF) and postrace EPI (r = 0.95; p < 0.001), and percentage change of EPI (r = 0.83; p = 0.012) were observed. The MAS was not associated to any metabolic or hormonal variable. These results suggest that psycho-physiological stress induced by the race elicited important changes in hormonal and metabolic variables and that %BF could be an important mediator of psycho-physiological stress in rally car drivers. Specific programs, including both strength and aerobic training, and nutritional plans should be implemented for appropriate conditioning of rally car drivers.

Physiological and selective attention demands during an international rally motor sport event

PURPOSE

To monitor physiological and attention responses of drivers and codrivers during a World Rally Championship (WRC) event.

METHODS

Observational data were collected from ten male drivers/codrivers on heart rate (HR), core body (T core) and skin temperature (T sk), hydration status (urine osmolality), fluid intake (self-report), and visual and auditory selective attention (performance tests). Measures were taken pre-, mid-, and postcompetition day and also during the precompetition reconnaissance.

RESULTS

In ambient temperatures of 20.1°C (in-car peak 33.9°C) mean (SD) peak HR and T core were significantly elevated (P < 0.05) during rally compared to reconnaissance (166 (17) versus 111 (16) beats · min(-1) and 38.5 (0.4) versus 37.6 (0.2)°C, resp.). Values during competitive stages were substantially higher in drivers. High urine osmolality was indicated in some drivers within competition. Attention was maintained during the event but was significantly lower prerally, though with considerable individual variation.

CONCLUSIONS

Environmental and physical demands during rally competition produced significant physiological responses. Challenges to thermoregulation, hydration status, and cognitive function need to be addressed to minimise potentially negative effects on performance and safety.

Optimizing the physical conditioning of the NASCAR sprint cup pit crew athlete

Stock car racing is the largest spectator sport in the United States. As a result, National Association for Stock Car Automobile Racing (NASCAR) Sprint Cup teams have begun to invest in strength and conditioning programs for their pit crew athletes. However, there is limited knowledge regarding the physical characteristics of elite NASCAR pit crew athletes, how the NASCAR Sprint Cup season affects basic physiological parameters such as body composition, and what is the most appropriate physical training program that meets the needs of a pit crew athlete. We conducted 3 experiments involving Sprint Cup motorsport athletes to determine predictors of success at the elite level, seasonal physiological changes, and appropriate physical training programs. Our results showed that hamstring flexibility (p = 0.015) and the score on the 2-tire front run test (p = 0.012) were significant predictors of NASCAR Sprint Cup Pit Crew athlete performance. Additionally, during the off season, pit crew athletes lost lean body mass, which did not return until the middle of the season. Therefore, a strength and conditioning program was developed to optimize pit crew athlete performance throughout the season. Implementation of this strength and conditioning program in 1 NASCAR Sprint Cup team demonstrated that pit crew athletes were able to prevent lean body mass loss and have increased muscle power output from the start of the season to the end of the season.

Physiological strain of stock car drivers during competitive racing

Heat strain experienced by motorsport athletes competing in National Association for Stock Car Automobile Racing (NASCAR) may be significant enough to impair performance or even result in a life-threatening accident. There is a need to carefully quantify heat strain during actual NASCAR race competitions in order to faithfully represent the magnitude of the problem and conceptualize future mitigation practices. The purpose of this investigation was to quantify the thermoregulatory and physiological strain associated with competitive stock car driving. Eight male stock car drivers (29.0±10.0yr; 176.2±3.3cm, 80.6±15.7kg) participated in sanctioned stock car races. Physiological measurements included intestinal core (Tc) and skin (Tsk) temperatures, heart rate (HR), blood pressure, and body mass before and after completion of the race. Pre-race Tc was 38.1±0.1°C which increased to 38.6±0.2°C post-race (p=0.001). Tsk increased from 36.1±0.2°C pre-race to 37.3±0.3°C post-race (p=0.001) whereas the core-to-skin temperature gradient decreased from a pre-race value of 2.0±0.3°C to 1.3±0.3°C post-race (p=0.005). HRs post-race were 80±0.1% of the drivers' age-predicted maximum HR. Physiological Strain Index (PSI) post-race was 4.9, which indicates moderate strain. Drivers' thermal sensation based on the ASHRAE Scale increased from 1.3±0.5 to 2.8±0.4, and their perception of exertion (RPE) responses also increased from 8.4±1.6 to 13.9±1.8 after competition. Heat strain associated with competitive stock car racing is significant. These findings suggest the need for heat mitigation practices and provide evidence that motorsport should consider strategies to become heat acclimatized to better meet the thermoregulatory and cardiovascular challenges of motorsport competition.

Bioenergetical and Cardiac Adaptations of Pilots to a 24-Hour Team Kart Race

This study aimed to evaluate energy expenditure (EE) and heart rate (HR) response in kart pilots to successive driving bouts during a 24-hour team race. Eight adult male pilots (22.8 ± 4.1 years) participated to a team 24-hour speedway kart race in Le Mans (France). They alternatively piloted a 390 cm kart. Each relay was 45 minutes long and each pilot performed 4 relays. For each pilot, mean speeds were calculated from lap-to-lap duration recordings using a telemetric infrared timing device. Heart rate values were recorded continuously on 5-second intervals using a portable cardiometric device. Total energy expenditure (EET) and physical activity ratio (PAR) were determined by accelerometry. To pilot a kart during 45 minutes at a mean speed around 62 km·h induces a 300-kcal EET, corresponding to a 5.6-Mets PAR. This effort is responsive for a 73 b·min increase in HR, from 84.1 ± 7.6 to 157.4 ± 11.0 b·min (82% maximal heart rate intensity). However, during this relay period, HR values seemed independent to mean speed performance and bioenergetical values. Thus, in the context of the 24-hour team race, the variability in effort made during each relay and relay succession did not alter bioenergetical adaptation of pilots to kart driving. The high EE and HR values would be better explained by both emotional stress and environmental constraints such as speedway configuration and vibrations. The way how these factors specifically influence bioenergetical demand, and their relative importance, has to be specified to optimize training procedure and recommendations.

Physical demands, injuries, and conditioning practices of stock car drivers

The purpose of this study was to assess the physical demands, injuries, and conditioning practices of stock car drivers. Forty stock car drivers from 27 states in the United States participated in the interviews for 43.9 ± 13.9 minutes. The interviews examined background information, the physical demands of racing, injuries associated with racing, and the athletic and fitness background and practices of the subjects. Numerical data were analyzed using Pearson's correlation coefficients. Responses to open-ended questions were analyzed using inductive content analysis. Results revealed significant correlation between track points standings and the length of the resistance training sessions (R = -0.71, p = 0.002) and subject self-assessment of their fitness (R = -0.53, p = 0.045). Results also revealed that "upper-body strength" was identified as the most important physical demand. Extreme fatigue was the most common feeling after a demanding race. Subjects reported that shoulder fatigue was the most common form of muscle soreness experienced after a race. Back and torso injuries were the most common injury, although head injuries most frequently required medical attention. The subjects' biggest fear was fire, followed closely by head and neck injury. The bench press and running were the most commonly performed resistance training and cardiovascular exercises, respectively. Subjects reported that their highest motivation for training was to improve their racing performance. Many subjects had athletic backgrounds with football identified as the sport they had most commonly participated in. This study provides additional detailed information. Results of this study can assist strength and conditioning professionals in the development of strength and conditioning programs for performance enhancement and injury prevention that are specific to the needs of this population of athletes.

The effect of competition on heart rate during kart driving: A field study

Background

Both the act of competing, which can create a kind of mental stress, and participation in motor sports, which induces physical stress from intense g-forces, are known to increase heart rate dramatically. However, little is known about the specific effect of competition on heart rate during motor sports, particularly during four-wheel car driving. The goal of this preliminary study, therefore, was to investigate whether competition increases heart rate under such situations.

Findings

The participants drove an entry-level formula kart during two competitive races and during solo driving against the clock while heart rate and g-forces were measured. Analyses showed that heart rate values during the races (168.8 beats/min) were significantly higher than those during solo driving (140.9 beats/min) and rest (75.1 beats/min).

Conclusions

The results of this preliminary study indicate that competition heightens heart rate during four-wheel car driving. Kart drivers should be concerned about maintaining good health and developing physical strength.

Responses of Motor-Sport Athletes to V8 Supercar Racing in Hot Conditions

Background:

Despite the thermal challenge of demanding workloads performed in high cabin temperatures while wearing heavy heat-retardant clothing, information on physiological responses to racing V8 Supercars in hot conditions is not readily available.

Purpose:

To describe the thermal, cardiovascular, and perceptual strain on V8 Supercar drivers competing in hot conditions.

Methods:

Thermal strain was indicated by body-core temperature using an ingested thermosensitive pill. Cardiovascular strain was assessed from heart rate, hydration status, and sweat rate. Perceptual strain was estimated from self-rated thermal sensation, thermal discomfort (modified Gagge scales), perceived exertion (Borg scale), and perceptual strain index.

Results:

Prerace body-core temperatures were (mean ± SD) 37.7°C ± 0.4°C (range 37.0°C to 38.2°C), rising to 39.0°C ± 0.4°C (range 38.4°C to 39.7°C) postrace. Driver heart rates were >160 and >170 beats/min for 85.3% and 46.7% of racing, respectively. Sweat rates were 1.06 ± 0.12 L/h or 13.4 ± 1.2 mL · kg−1 · h−1, and postrace dehydration was 0.6% ± 0.6% of prerace body mass. Drivers rated thermal sensation as hot (10.3 ± 0.9), thermal discomfort as uncomfortable (3.1 ± 1.0), and perceived exertion as very hard to very, very hard (8.7 ± 1.7) after the races. Overall physiological and perceptual strain were 7.4 ± 1.0 and 7.1 ± 1.2, respectively.

Conclusions:

Despite the use of cooling, V8 Supercar drivers endure thermal, cardiovascular, and perceptual strain during brief driving bouts in hot conditions.

Reactivity, stability, and strength performance capacity in motor sports

BACKGROUND

Racing drivers require multifaceted cognitive and physical abilities in a multitasking situation. A knowledge of their physical capacities may help to improve fitness and performance.

OBJECTIVE

To compare reaction time, stability performance capacity, and strength performance capacity of élite racing drivers with those of age-matched, physically active controls.

METHODS

Eight élite racing drivers and 10 physically active controls matched for age and weight were tested in a reaction and determination test requiring upper and lower extremity responses to visual and audio cues. Further tests comprised evaluation of one-leg postural stability on a two-dimensional moveable platform, measures of maximum strength performance capacity of the extensors of the leg on a leg press, and a test of force capacity of the arms in a sitting position at a steering wheel. An additional arm endurance test consisted of isometric work at the steering wheel at +30 degrees and -30 degrees where an eccentric threshold load of 30 N.m was applied. Subjects had to hold the end positions above this threshold until exhaustion. Univariate one way analysis of variance (alpha = 0.05) including a Bonferroni adjustment was used to detect group differences between the drivers and controls.

RESULTS

The reaction time of the racing drivers was significantly faster than the controls (p = 0.004). The following motor reaction time and reaction times in the multiple determination test did not differ between the groups. No significant differences (p>0.05) were found for postural stability, leg extensor strength, or arm strength and endurance.

CONCLUSIONS

Racing drivers have faster reaction times than age-matched physically active controls. Further development of motor sport-specific test protocols is suggested. According to the requirements of motor racing, strength and sensorimotor performance capacity can potentially be improved.

Automobilismo: no calor da competição

O presente artigo questiona o papel do calor como um fator de risco adicional para o acidente que vitimou Ayrton Senna. O automobilismo de competição constitui um desafio biológico, uma situação estressante do ponto de vista mental e físico. A manutenção da performance depende da disponibilidade de carboidratos e oxigênio, hidratação adequada e temperatura interna constante entre 37 e 38 graus centígrados. A dissipação do calor produzido pelo metabolismo ocorre através do aumento do fluxo de sangue para pele e produção de suor e manter a temperatura cerebral constante se constitui num problema permanente. Verificou-se experimentalmente que a energia necessária para dirigir um automóvel de corrida é comparável a um esporte como o voleibol. Durante uma corrida, o indivíduo está exposto a um microambiente quente na cabina, que pode atingir 50ºC, gerado por fontes de calor mecânicas e ambientais. O bloqueio da evaporação do suor pelo macacão resulta em umidade e desconforto pessoal, o que implica maior esforço mental para dirigir o carro. As medidas contra o calor começam antes da corrida, cuidando-se do estado nutricional, da hidratação e principalmente do condicionamento físico através de exercícios aeróbios regulares e adequados, que permitem aumentar a capacidade de trabalho e a tolerância ao calor, o que resulta em menor fadiga durante a corrida. Outro procedimento importante deveria ser a aclimatação prévia dos pilotos aos ambientes quentes e úmidos. Deve-se fazer o possível para reduzir o aquecimento do veículo e respeitar o sistema de bandeiras de advertência para os riscos de hipertermia. Em conclusão, embora Ayrton Senna fosse um indivíduo com maior risco de desenvolver hipertermia, independentemente de outras causas, não parece ter havido tempo de corrida suficiente para haver produção de calor metabólico capaz de aumentar excessivamente a temperatura interna do piloto nas condições ambientais do autódromo no dia de sua morte.