Profiling the physical load on riders of top-level motorcycle circuit racing

The Relationship Among Body Composition and Anaerobic Capacity and the Sport Level of Elite Male Motorcycle Speedway Riders

The main objective of this study was to investigate the relationship among anaerobic capacity, body composition, and sport level of male junior and senior speedway riders. Sixty riders of professional clubs in the Polish top motorcycle speedway league participated in this study. They were divided into two equal groups (n = 30): junior (age = 19.7 ± 1.1 years) and senior (age = 29.7 ± 5.2). Body composition assessment, Wingate test (WAnT) on cycloergometer, with analysis of acute cardiorespiratory and biochemical responses were performed. Sport level was defined as the number of heats (races) won, winning percentage, total points scored during the season, and average points scored per heat. Seniors had higher point ratings indicating sport levels. As compared to the seniors, the juniors had lower BMI 4% (p < 0.01) and fat tissue mass by 20.5% (p < 0.01). A higher power decrease of 2.3% (p < 0.05) in the WAnT test was found in seniors. Body height negatively correlated with all indicators of seniors’ sport level (r = −0.41 to −0.55). Peak power output negatively correlated with seniors’ sport level (r = −0.39 to −0.41). Among the seniors, there was a negative correlation between post-exercise hydrogen ion concentration (r = −0.38), carbon dioxide partial pressure (r = −0.45) and average points scored per season. Conclusion: The anthropometric characteristics of body height, lean body mass and body surface area, are significantly correlated with the sport levels of the seniors motorcycle speedway riders. When selecting motorcycle speedway riders, use of these anthropometric characteristics may aid in determining the riders with the most potential to be successful. Metabolic acidosis tolerance and gas exchange efficiency show significance in seniors, indicating the need for intense exercise sessions.

Effectiveness of Custom Foot Insoles to Decrease Plantar Pressure: A Cross-over Randomized Trial Study

Background: Harderness insoles decrease plantar pressure and reduce the foot injury incidence in sport. The purpose of our study was to analyze the plantar pressure variation in moto riders after riding in a real speed circuit with a custom foot 52⁰ Shore EVA insole. Methods: A crossover randomized trial study was performed (consent no. #050520165316). Riders were assessed by an expert motorsport senior podiatry. The participants’ mean age was 35 ± 3.29. Participants completed a 20 min training riding with their own motorcycle in a real speed circuit. Plantar pressures were registered with a baropodometric platform evaluating an Ethyl Vinyl Acetate custom foot insole (CFI) manufactured with 3 mm thickness and 52° Shore A hardness. The Plantar pressures were registered before riding, after riding without EVA insole, and after riding with EVA insole. Results: Total Plantar pressures in right and left foot, and total surface area decrease after riding with EVA insoles. Conclusion: The use of an EVA insole with 52⁰ shore A hardness riding on a motorcycle in speed circuit decreased the total plantar pressures and surface areas values.

Muscle Fatigue When Riding a Motorcycle: A Case Study

This case study was conducted to assess muscle pattern, as measured by surface electromyography (sEMG), and its changes during a controlled superbike closed-road track training session. The sEMG signals were recorded unilaterally from biceps brachii (BB), triceps brachii (TB), anterior and posterior part of the deltoid (DA and DP respectively), flexor digitorum superficialis (FS), extensor carpi radialis (CR), extensor digitorum communis (ED) and pectoralis major (PM) during three rounds of 30 min. sEMG signals selected for analysis came from the beginning of the braking action to the way-out of the curves of interest. Considering the laps and rounds as a whole and focusing on the forearm muscles, ED was more systematically (84%) assigned to a state of fatigue than FS (44%) and CR (39%). On the opposite, the TB and DP muscles showed a predominant state of force increase (72%). Whereas the BB showed alternatively a state of fatigue or force increase depending on the side of the curve, when taking into account only the sharpest curves, it showed a predominant state of force increase. In conclusion, the fact that forearm muscles must endure a long-lasting maintenance of considerable activity levels explains why they easily got into a state of fatigue. Moreover, TB and DA are particularly relevant when cornering.

Forearm muscles fatigue induced by repetitive braking on a motorcycle is best discriminated by specific kinetic parameters

Maneuvering a motorcycle in racing conditions or for prolonged time is sufficiently demanding that on many occasions forearm muscles reach a state of functional failure when riders cannot properly brake or operate the throttle. This study intends to discriminate which ones of the several dynamometric parameters used in the literature to characterize the Force-time (F-t) curve during voluntary contractions are more sensitive to neuromuscular fatigue in simulated motorcycle-riding conditions. Thirty-three adults performed an intermittent fatiguing protocol (IFP) that simulated the brake-pulling and throttle-twisting actions, by using a hydraulic system equipped with a pressure sensor. Sixty pressure-time (P-t) curve parameters, including the rate of pressure development (RPD) and area under the curve were measured to characterize the time course of the braking maximal voluntary contraction (MVC). Two types of variables were used to analyze the P-t curve: 1) Times interval (from 0 to 30-50-100-500-1000 and 2000 ms); 2) Percentages of MVC (10-30-60-90%MVC). Overall significant (p ≤ 0.05) fatigue-related declines were observed only at time intervals longer than 100 ms and contraction intensities higher than 30%MVC. Strong and significant linear declines (p < 0.001) were observed at 500 ms and 1 s for normalized pressures, as well as for the ratio RPD_60%MVC/MVC (p < 0.003) throughout the IFP. Our results suggest considering RPD at time windows of 0–500 ms and 0–1 s, and contraction intensities comprised between 30% and 60% of MVC, as more suitable criteria to study fatigue-related decrements in performance rather than the classical MVC force.

Influence of Different Hardness Custom Foot Insoles in the Electromyography Activity Patterns of the Thigh and Hip Muscles during Motorcycling Sport: A Crossover Study

Nowadays, the use of insoles in sport practice have been recognized to decrease the foot and lower limb injury patterns. The aim of this study was to analyse the effect of four types of hardness insoles (HI) in the activity patterns of the hip and thigh muscles (HTM) in motoriders during motorcycling sport. The study was a crossover trial. Subjects were elite motoriders. The mean age was 33 ± 5.14 years. Electromyography (EMG) of hip and thigh muscles (HTM) data was registered via surface while subjects were riding on an elite motorcycle simulator. Subjects had to complete different tests with randomly hardest insoles (HI): 1: only polypropylene (58° D Shore); 2: Polypropylene (58° D Shore) with selective aluminium in hallux and metatarsal heads (60 HB Brinell hardness); 3: Ethylene vinyl acetate (EVA) (52° A Shore); and finally, 4: Ordinary EVA (25° A Shore) as the control. EMG patterns of the HTM, riding on an elite motorcycle simulator, showed the lowest peak amplitude with the insoles with polypropylene and selective aluminium. Using the hardest insoles in our study (selective aluminium) the EMG amplitude peaks decreased in all HTM.

High-speed helmeted head impacts in motorcycling: A computational study

The motorcyclist is exposed to the risk of falling and impacting ground head-first at a wide range of travelling speeds - from a speed limit of less than 50 km/h on the urban road to the race circuit where speed can reach well above 200 km/h. However, motorcycle helmets today are tested at a single and much lower impact speed, i.e. 30 km/h. There is a knowledge gap in understanding the dynamics and head impact responses at high travelling speeds due to the limitation of existing laboratory rigs. This study used a finite element head model coupled with a motorcycle helmet model to simulate head-first falls at travelling speed (or tangential velocity at impact) from 0 to 216 km/h. The effect of different falling heights (1.6 m and 0.25 m) and coefficient of frictions (0.20 and 0.45) between the helmet outer shell and ground were also examined. The simulation results were analysed together with the analytical model to better comprehend rolling and/or sliding phenomena that are often observed in helmet oblique impacts. Three types of helmet-to-ground interactions are found when the helmet impacts ground from low to high tangential velocities: (1) helmet rolling without slipping; (2) a combination of sliding and rolling; and (3) continuous sliding. The tangential impulse transmitted to the head-helmet system, peak angular head kinematics and brain strain increase almost linearly with the tangential velocity when the helmet rolls but plateaus when the helmet slides. The critical tangential velocity at which the motion transit from the rolling regime to the sliding regime depends on both the falling height and friction coefficient. Typically, for a fall height of 1.63 m and a friction coefficient of 0.45, the rolling/sliding transition occurs at a tangential velocity of 10.8 m/s (38.9 km/h). Low sliding resistance in helmet design, i.e. by the means of a lower friction coefficient between the helmet outer shell and ground, has shown a higher reduction of brain tissue strain in the sliding regime than in the rolling regime. This study uncovers the underlying dynamics of rolling and sliding phenomena in high-speed oblique impacts, which largely affect head impact biomechanics. Besides, the study highlights the importance of testing helmets at speeds covering both the rolling and sliding regime since potential designs for improved head protection at high-speed impacts can be more distinguishable in the sliding regime than in the rolling regime.

A physical profile of novice and experienced professional motorcycle speedway riders

BACKGROUND

There is a paucity of data relating to Professional Motorcycle Speedway riders physical characteristics despite its growing popularity.

METHODS

The participants were divided into two categories depending on their Calculated Match Average (CMA); high performers (CMA>5.0, N.=16) and low performers (CMA<4.9, N.=16). Anthropometric data, isometric hand grip strength, isometric knee extension strength, dynamic stability of the upper and lower limbs and functional movement scores were measured to establish differences between high and low performing professional speedway riders.

RESULTS

High performing riders had significantly better functional movement screen composite scores than low performers (P=0.003) and hurdle step (P=0.002) and shoulder mobility movements (P=0.032). Significant hand grip and leg strength was observed in riders right limbs compared to their left (P=0.004 and P=0.000 respectively) and greater dynamic stability in their right leg than left (P=0.011). High performing riders had greater grip strength (right hand P=0.016 and left hand P=0.034) and knee extension strength in the right (P=0.036) legs than their low performing counterparts.

CONCLUSIONS

The findings of this study provide a benchmark of physical characteristics of high and low performing riders, highlighting mobility, functional movement, dynamic stability and isometric strength as essential attributes of an elite rider.

Electromyographic Evaluation of the Impacts of Different Insoles in the Activity Patterns of the Lower Limb Muscles during Sport Motorcycling: A Cross-Over Trial

Customized foot insoles (CFI) have been recognized to reduce the prevalence of foot disorders in sport. The aim of this study was to evaluate the effect of four types of CFI on the activity patterns of the lower limb muscles (LLM) in healthy people during sport motorcycling. Methods: This was a cross-over trial (NCT03734133. Participants were recruited from an outpatient foot specialist clinic. Their mean age was 33 ± 5.14 years. While participants were sport motorcycling in a simulator, the electromyography (EMG) function was registered for LLM via surface electrodes. Participants completed separate tests while wearing one of four types of CFI: (1) only polypropylene (58° Shore D), (2) selective aluminum (60 HB Brinell hardness) in metatarsal and first hallux areas and polypropylene elsewhere (58° Shore D), (3) ethylene vinyl acetate (EVA) (52° Shore A), and (4) standard EVA (25° Shore A) as the control. Results: The activity patterns of the LLM while sport motorcycling showed significantly lower peak amplitude for the selective aluminum CFI than the other types of CFI. Conclusion: EMG amplitude peaks for several LLM were smaller for the hardest CFI (selective aluminum 60 HB Brinell hardness) than the other CFIs (polypropylene 58° Shore D, EVA 52° Shore A, and standard EVA 25° Shore A), except for the fibularis longus in right curves that is increased when the knee touches the road increasing the stability.

Trend Analysis of 20 Years of FIM Road Racing Grand Prix Motorcycle World Championship

Purpose: The technological advancements in motorcycle road racing have ensured the evolution of motorcycle performance; however, it is unknown whether these advancements have resulted in increased speed and therefore risk. To better understand the top level of this sport and inform future regulations, performance-related strategies, and safety procedures, this study aimed to (1) analyze and describe how the performance characteristics of the top class of the Fédération Internationale de Motocyclisme Grand Prix motorcycle world championship (GPWC) have changed with time and (2) quantify potential interactions between performance data (ie, crashes, speed, and environmental conditions). Methods: Variables such as top 10 riders’ speed of racing, crashes, starting position of winner, participants, and environmental conditions were collected from official race reports from 1997 to 2016. Data standardization was also ensured by including only dry competitions in the analysis. Results: The mean racing speed ranged from a minimum of 155 (7.27) km·h−1 (year 2000) to a maximum of 165 (6.48) km·h−1 (year 2015). Linear mixed-model analysis revealed that the variables year and class significantly influenced changes in mean speed (faster racing). Per race, 12–14% of starters (95% confidence interval) suffered a crash. No significant associations were found between crashes and mean speed, ground temperature, air temperature, or air humidity. Conclusions: The speed of dry racing of the top class of the GPWC has increased over a 20-y span. Motorcycle circuit racing riders should consider the importance of being prepared to cope with crashing events to minimize chances of injury.