The effectiveness of sprint athletes in removing lactate after reaching maximum effort

FERDI TAHIROGLU, SEYED HOUTAN SHAHIDI

Faculty of Sport Sciences, Department of Sports Coaching, Istanbul Gedik University, Istanbul, Turkey.

Summary. Background. This investigation sought to investigate the time-dependent changes in blood lactate levels and oxygen intake (VO₂) after maximal sprint efforts in elite 100-m sprinters, with an emphasis on recovery rates and their relevance to performance tactics for sprinters. This research provides a comprehensive analysis of metabolic recovery patterns within this underrepresented athletic group through the application of a bi-exponential model. Methods. Twenty elite 100-meter sprinters underwent a graded exercise test and a 30-second Wingate Anaerobic Test as part of the methods. Measurements of blood lactate levels were taken at three specific points: at the start of exercise, immediately after exercise, and at various intervals of up to 20 minutes following exercise. Oxygen consumption was tracked in real-time throughout and following the GXT. Results. Typically, peak blood lactate levels of 14.9 ± 3.5 mmol/L were attained at 3 minutes following exercise. The rate at which lactate is cleared from the body occurs in two distinct stages. The first stage was a quick process (lasting around 60 seconds), and the second stage was much slower (taking approximately 300 seconds). The recovery of VO₂ also showed a bi-exponential pattern, with time constants associated with quick phosphocreatine resynthesis and prolonged oxidative recovery. Average peak VO₂ levels measured 45.4 ± 4.1 mL·kg⁻¹·min⁻¹, which matches what is typically seen in trained athletes. A sophisticated modelling method uncovered detailed patterns of recovery for individual athletes, suggesting ways to fine-tune rest breaks and track fatigue levels during sprint training, which specifically involves post-exertion exhaustion. Conclusions. The research offers new findings on the rates of lactate removal and oxygen usage recovery in top-level sprinters by combining longer data collection periods and a two-stage mathematical analysis. These findings may suggest implementing more tailored recovery plans in sprint training and contribute to the increasing acknowledgment of VO₂ kinetics as an indicator of both performance and physical durability.

Key words. Lactate, VO₂ (oxygen intake), recovery, elite sprinters, bi-exponential model.

Efficacia degli atleti sprint nell’eliminare il lattato dopo aver raggiunto il massimo sforzo

Contesto. Questo studio ha cercato di analizzare le variazioni tempo-dipendenti dei livelli di lattato nel sangue e dell’assunzione di ossigeno (VO₂) dopo sforzi di sprint massimali in sprinter d’élite sui 100 metri, con particolare attenzione ai tassi di recupero e alla loro rilevanza per le tattiche di prestazione degli sprinter. Questa ricerca fornisce un’analisi completa dei modelli di recupero metabolico all’interno di questo gruppo atletico sottorappresentato attraverso l’applicazione di un modello biesponenziale. Metodi. Venti sprinter d’élite sui 100 metri sono stati sottoposti a un test da sforzo graduato e a un Wingate Anaerobic Test di 30 secondi come parte dei metodi. Le misurazioni dei livelli di lattato nel sangue sono state effettuate in tre momenti specifici: all’inizio dell’esercizio, immediatamente dopo l’esercizio e a vari intervalli fino a 20 minuti dopo l’esercizio. Il consumo di ossigeno è stato monitorato in tempo reale durante e dopo il GXT. Risultati. In genere, i livelli di picco di lattato nel sangue, pari a 14,9 ± 3,5 mmol/L, venivano raggiunti 3 minuti dopo l’esercizio. La velocità con cui il lattato viene eliminato dall’organismo avviene in due fasi distinte. La prima fase era un processo rapido (della durata di circa 60 secondi), mentre la seconda fase era molto più lenta (della durata di circa 300 secondi). Anche il recupero del VO₂ ha mostrato un andamento biesponenziale, con costanti di tempo associate a una rapida resintesi della fosfocreatina e a un prolungato recupero ossidativo. I livelli medi di picco di VO₂ erano pari a 45,4 ± 4,1 mL·kg·min·, valori che corrispondono a quelli tipicamente osservati negli atleti allenati. Un sofisticato metodo di modellazione ha evidenziato modelli dettagliati di recupero per i singoli atleti, suggerendo modalità per ottimizzare le pause di riposo e monitorare i livelli di affaticamento durante l’allenamento di velocità, che prevede specificamente l’esaurimento post-sforzo. Conclusioni. La ricerca offre nuove scoperte sui tassi di rimozione del lattato e di recupero del consumo di ossigeno negli sprinter di alto livello, combinando periodi di raccolta dati più lunghi e un’analisi matematica a due fasi. Questi risultati potrebbero suggerire l’implementazione di piani di recupero più personalizzati nell’allenamento per gli sprint e contribuire al crescente riconoscimento della cinetica del VO₂ come indicatore sia della prestazione che della resistenza fisica.

Parole chiave. Lattato, VO₂ (assunzione di ossigeno), recupero, velocisti élite, modello bi-esponenziale.

Introduction

The rates at which lactate is released from the muscle tissue into the bloodstream and then cleared are crucial factors influencing athletic performance and recovery, particularly in sprint events1. A widely accepted method for modeling these dynamics is the four-parameter bi-exponential model, which employs serial blood lactate measurements collected before and up to 30 minutes following exercise. This model accurately portrays both the rate of lactate release from the body’s extravascular compartments into the bloodstream and the rate of its elimination, providing significant insights into how well-trained sprinters metabolize during periods of high-intensity exercise2,3. The concentration of lactate in the blood is a commonly used biomarker for determining the role of anaerobic glycolysis in generating energy and for gauging the intensity of exercise4. Research has shown that the observed lactate levels are a reflection of the equilibrium between the production and elimination processes in the body5. During steady-state, submaximal exercise, blood lactate levels remain constant when the rate of lactate entering the body equals the rate of its leaving. Oxygen intake (VO₂) at this time accurately measures the body’s total energy usage, unaffected by the rate of lactate conversion6,7. At intensities higher than the threshold, blood lactate levels increase as a result of either boosted production or hindered clearance, or both8. After intense physical activity, active recovery processes help the liver break down lactic acid into glucose via the Cori cycle9,10. It is crucial to monitor blood lactate levels not only to gauge exercise intensity and lactate threshold but also to assess post-exercise recovery and metabolic strain during high-intensity training sessions11,12. Anaerobic pathways are a major contributor to energy production in sprinting events. In the 400-m sprint, anaerobic metabolism is responsible for roughly 63% of the total energy expenditure in males. In particular, during a 100-m sprint that lasts approximately 10 seconds, the energy supply is almost exclusively anaerobic, comprising an equal split between phosphocreatine breakdown and anaerobic glycolysis13,14. High-energy requirements during rapid periods of activity lead to substantial lactate buildup, which typically peaks at levels around 13.2 mmol/L after exercise in highly trained sprinters15. Previous research has highlighted the significance of timing blood samples to precisely measure peak lactate levels. Studies by Gupta et al. in 2021 and Hanon et al. in 201016,17 suggest that the highest levels usually emerge between 3 and 5 minutes after exercise. Zajac15 suggests that sampling frequencies of 1–2 minutes be used more often and supported the continuation of monitoring beyond the initial 60 minutes to obtain a clearer understanding of lactate kinetics. Significant research has been conducted, yet there remains no general agreement regarding the most suitable timeframe for post-exercise blood sampling in order to accurately identify peak blood lactate levels, particularly in highly trained sprinters who engage in maximum effort performances. Decreasing the sampling frequency and duration, while maintaining accuracy, could substantially improve athlete comfort and logistical feasibility during performance testing. Research on lactate responses has been conducted in a range of track events, such as 200 m and 400 m races, but few studies have focused exclusively on highly trained 100-meter sprinters whose distinct metabolic characteristics are influenced by the extremely high intensity and brief duration of their events. This study sought to investigate how blood lactate levels change over time after extremely intense exercise in highly trained 100 m sprinters and to identify the most suitable moment to record the highest lactate levels. This study aims to refine the measurement protocols and improve the understanding of recovery kinetics in sprint-specific populations by using a bi-exponential model and sampling after exercise for an additional 20 minutes.

Materials and methods

Participants

Twenty well-trained 100 m sprint athletes participated in this investigation. Individuals involved in the study were within the age range of 18 to 35 years and had at least five years of experience in structured sprint training, as well as a history of competing at either the national or international level. Before testing, detailed information on age, body measurements, and maximum oxygen consumption (VO₂peak) had been recorded, as shown in table 1.




To participate, individuals had to be in overall good health, have no recorded cardiovascular, respiratory, or metabolic diseases, and not be dealing with current injuries or health issues that could hinder their performance. All participants were non-smokers and followed a set of pre-test protocols, requiring them to abstain from food, caffeine, and physical activity for a minimum of eight hours before testing. Informed consent was obtained from each participant before participation.

Athletes not meeting the specified age requirements, lacking sufficient training history, suffering from ongoing medical issues, recent injuries, smoking, or being unable to finish the Graded Exercise Test (GXT) and the Wingate Anaerobic Test were excluded. Informed consent was obtained from all participants or their legal guardians, following comprehensive explanations of the study’s objectives and associated risks.

Ethical approval

This study was conducted by the Declaration of Helsinki and received pre-approval from the local ethical committee of Istanbul Gedik University (Approval ID: E-56365223-050.02.04-2023.137548.20).

Anthropometric measurements

Measurements of body height and mass were performed using a stadiometer (Seca 213, manufactured by Seca GmbH & Co. KG, based in Hamburg, Germany), which provided an accuracy of 1 mm for body height and 0.1 kg for body mass. The body composition, including fat mass and lean body mass, was evaluated using a multi-frequency bioelectrical impedance analysis device, specifically the InBody MC780 from Tanita, a Tokyo, Japan-based company.

Graded Exercise Test

Participants completed a graded exercise test using an electrodynamic braked cycle ergometer, specifically a Monark 939 E model from Sweden. The protocol started with a standardized 10-minute warm-up at 75 watts and a cadence of 60–90 revolutions per minute. The incremental phase was initiated at 100 W and incremented by 25 W every minute until voluntary exhaustion (figure 1).




A Polar Heart Rate Monitor (Pearson Electro Inc., New York, USA, was used to continuously monitor the heart rate (HR) throughout the test. The peak power output, oxygen uptake, and blood lactate concentration were quantified. VO₂max was considered achieved when participants satisfied at least two of the following conditions. VO₂ levels remain steady despite a workload increase of less than 150 mL/min. The rating for perceived exertion on the Borg Scale is greater than 18. Heart rates exceeding 90% of the predicted maximum for one’s age.

30-second All-out Sprints of Cycling (Wingate Anaerobic Test)

A mechanically braked ergometer (Monark 894 E, Sweden) was used for a single 30-second Wingate Anaerobic Test by the participants. The test started with a 5-minute warm-up at 0.5 watts per kilogram and featured two short all-out sprints (lasting 3 seconds each) during the third and fourth minutes. Following a 10-minute rest period, the participants performed an all-out sprint in resistance equivalent to 7.5% of their body mass. Blood samples were taken from the fingertip before the test, immediately after, and at 2-minute intervals up to 14 minutes post-exercise to measure blood lactate levels. Measurements were conducted using a Lactate Scout 4 analyzer (EKF, a German company) (figure 2).




Gas analysis and aerobic threshold determination

The measurement of oxygen uptake (VO₂) and ventilation (VE) was performed using a semi-portable gas analyzer, specifically the Fitmate Pro model from (ed, located in Rome, Italy. Prior to each test, the device underwent automatic gas calibration, whereas the turbine flowmeter was calibrated manually using a 3-L syringe. The highest VO₂ value during the GXT was identified as the peak VO₂ value, which was calculated as the average VO₂ over a 30-s rolling period. The aerobic gas exchange threshold was calculated by analyzing the relationship between ventilation rate and oxygen uptake and by identifying the point at which the rate of change began to accelerate, signifying the transition to anaerobic metabolism.

Laboratory conditions and pre-testing precautions

The tests were set to take place between 17:00 and 19:00 in order to minimize circadian rhythm fluctuations. The tests were scheduled between 17:00 and 19:00 h to reduce circadian rhythm variability. Test subjects were required to refrain from eating (except drinking water) for a 2-hour period before the test, and to abstain from consuming caffeine, alcohol, tobacco, or strenuous physical activity for 24 hours before the test.

Data analysis

All data were tested for normality and homogeneity of variance using the Kolmogorov-Smirnov and Shapiro-Wilk tests. The statistics are summarized as the mean plus or minus the standard deviation (SD). A one-way analysis of variance (ANOVA) was performed to identify differences between conditions, and subsequent pairwise analyses were conducted using independent or paired sample t-tests as necessary. The Wingate performance variables were specified as follows. Peak Power refers to the highest mechanical power output and is determined over a 5-second period. The lowest mechanical power output recorded over any 5-s period is referred to as the Minimum Power (MP). The Mean Power (AP) is the steady average power output achieved over the course of a 30-secon30-s The Power Drop (PD) denotes the disparity between the predicted power (PP) and measured power (MP). The Fatigue Index (FI) was calculated by expressing PD as a percentage of PP. Power metrics were presented in both absolute (watts) and relative (watts per kilogram) formats. The significance threshold was predetermined to be p ≤ 0.05. Statistical analyses were conducted using the SPSS Statistics software for Windows, version 25.0 (Armonk, New York, USA).

Mathematical analyses

The analysis method for blood lactate concentration using a bi-exponential model involves aggregating data from elite sprinters during recovery. This method employs the equation: [LA] (t) = LA0 + A1 (1−e−γ1t) + A2 (1−e−γ2t) where [LA] (t) represents lactate concentration at time t, LA0 is the initial concentration, A1 and A2 are amplitudes, and γ1 and γ2 are rate constants. Parameters are estimated using nonlinear least-squares regression, and model fit quality is assessed via the coefficient of determination (R²)18.

VO2 kinetics during recovery

The kinetics of oxygen uptake (VO₂) during the recovery phase after a 30-second Wingate test were modeled using a single exponential equation19. This approach provides a detailed understanding of the physiological processes involved in the recovery period following high-intensity exercise.

Single exponential model

The oxygen uptake kinetics were described using the following equation:

V˙O2 (t) = A1⋅exp (−(t−TD)/τ1) + V˙O2, base

where:

• V˙O2 (t) represents the oxygen uptake at time t.

• V˙O2, the base is the baseline oxygen uptake before exercise.

• A1 is the amplitude of the fast phase of oxygen uptake.

• t is the time elapsed during the recovery phase.

• TD is the time delay before the onset of the VO₂ response.

• τ1 is the time constant of the fast phase, indicating the rate at which VO₂ increases during recovery.

Parameters and calculations

To quantify the oxygen debt incurred during the recovery period, the following calculations were performed:

1. Fast Oxygen Debt: the rapid phase of oxygen uptake, which primarily reflects the replenishment of phosphocreatine stores and the initial re-oxygenation of myoglobin, was calculated as Fast Oxygen Debt = A1⋅τ1.

2. Slow Oxygen Debt: in scenarios where a bi-exponential model was used, the slow phase, representing ongoing oxidative metabolism and clearance of metabolic by-products, was calculated as Slow Oxygen Debt = A2⋅τ2. Here, A2 and τ2 denote the amplitude and time constant of the slow phase, respectively.

Results

Table 1 provides a summary of the participants’ 100-meter sprint times, results of the graded exercise test, and blood lactate levels. On average, participants completed 9 stages with a standard deviation of one during the GXT, indicating high exercise tolerance and aerobic fitness. The highest concentration of blood lactate after exercise was 14.9 ± 3.5 mmol/L, demonstrating the significant anaerobic glycolytic contribution during intense physical activity and the participants’ well-developed anaerobic capacity.

Wingate 30-Second Test results summary

The highest mechanical power recorded during the Wingate test was 14.2 ± 1.0 W/kg, which was achieved at the start of the test within the first few seconds. This value represents the highest anaerobic power level of the participants. The average power produced over the full 30-s period was 9.9 ± 0.2 W/kg, which served as a measure of the athletes’ total anaerobic capacity. A 56.1 ± 6% average power drop was observed from peak to minimum power output, highlighting a swift onset of fatigue and the rapid depletion of anaerobic energy reserves. The peak power was achieved in 2.1 ± 0.6 seconds, demonstrating the athletes’ capacity for swift generation of maximal power, a critical element of explosive sprint performance.

Biexponential fit of lactate recovery for all subjects

The graph in figure 3 illustrates biexponential fits for each participant’s lactate recovery data, where distinct shapes signify different subjects.




Scatter points represent the actual data, whereas the fitted biexponential models are represented by lines.

Bi-exponential Fit of VO2

The graph illustrates the kinetics of VO2 (oxygen consumption) over 10 minutes following the 30-s Wingate test (figure 4).




The initial sharp decline marks the beginning of the rapid recovery phase, followed by a gradual slowdown, indicative of a slow recovery phase. The data points align very closely with the model, suggesting a strong correlation. Physiological variables are typically described using a bi-exponential function, which is a widely accepted method for modeling recovery kinetics.

Discussion

This research aimed to clarify the time-dependent patterns of blood lactate levels and oxygen usage after extremely intense efforts in sprinters. Previous studies have examined lactate and VO₂ kinetics in either mixed or endurance-based groups; however, this research is one of the few to use a bi-exponential modeling approach focused specifically on sprint athletes, offering a more in-depth understanding of their unique recovery traits. The extent of physiological detail achieved in this context enables the development of more targeted training and monitoring approaches, representing a new and useful advancement in the study of sprint performance. The peak blood lactate concentration was reached approximately 3 minutes after exercise, which is in line with previous research by Gupta et al.16, where similar peak lactate levels following intense 400-meter sprint efforts were observed. The timing of this is a reflection of the primary part anaerobic glycolysis plays in maintaining high power output during short-duration, maximal-intensity exercise20. Our study’s observed peak lactate concentration of (14.9 ± 3.5 mmol/L) aligns with previously documented values in well-trained sprint athletes, as seen in Zajac’s15 report of 13.2 mmol/L, thereby strengthening the credibility of our data within this athletic group. The bi-exponential decay pattern in lactate clearance is indicative of a two-phase recovery process. The initial rapid phase, lasting approximately 60 seconds (τ₁), is thought to be a result of lactate oxidation and gluconeogenesis by muscles and tissues actively engaged in the process21. Conversely, the slower secondary phase, which occurs around 300 seconds (τ₂), is likely attributed to lactate utilization by less active muscles and the liver22. The biphasic pattern highlights the physiological intricacy of lactate removal and underscores the need for prolonged observation to comprehensively capture the dynamics of recovery23. Timing the collection of blood samples is crucial for accurately measuring the highest lactate levels. Our data confirms that the 3-minute mark after exercise is a trustworthy indicator of the maximum response, but lengthening the sampling duration to 20 minutes, as suggested by Zajac15, allows for a more comprehensive analysis of each person’s lactate removal patterns. A holistic strategy could help professionals in developing more efficient training and recovery programs, tailored to the athlete’s metabolic response, which in turn would improve performance and lower the chance of overtraining. Our study showed that VO₂ kinetics initially rose quickly during a graded exercise test, achieving a peak before undergoing a two-part decrease during the recovery period. The initial phase of oxygen recovery was marked by a fast rate, indicated by a time constant (τ1) of approximately 60 seconds. This period is characterized by the quick replenishment of phosphocreatine stores and initial re-oxygenation of myoglobin24,25. The recovery phase is critical for prompt recovery and preparation for subsequent high-intensity exercise sessions. A slower phase, lasting approximately 300 seconds in terms of time constant (τ2), is indicative of ongoing oxidative metabolic processes and the removal of metabolic by-products, including lactate and hydrogen ions. Our study’s findings of the fast phase amplitude (A1 = 2.0 L/min) and slow phase amplitude (A2 = 1.0 L/min) are consistent with previous research on elite athletes, suggesting a well-developed ability for both quick and extended recovery processes6.

Our findings align with previous studies that have characterized the biphasic nature of VO₂ recovery kinetics in trained athletes. Specifically, Dupont and Berthoin26 demonstrated distinct fast and slow components of VO₂ recovery following high-intensity exercise, which correspond to the rapid replenishment of phosphocreatine and the slower metabolic processes such as lactate clearance and acid-base regulation. Similarly, Tomlin and Wenger27 emphasized that both VO₂peak and the speed of recovery are important determinants of repeated sprint ability, especially in highly trained individuals. In our study, the recorded VO₂peak value of 45.4 ± 4.1 ml·kg⁻¹·min⁻¹ reflects a well-developed aerobic system, which plays a vital supportive role even in predominantly anaerobic sports such as sprinting. While not unusually high for endurance athletes, this value is noteworthy within the context of sprint performance, where rapid recovery between repeated efforts can be decisive. As pointed out by Buchheit and Ufland28 sprint-trained athletes benefit from enhanced oxygen kinetics to support both phosphocreatine resynthesis and post-exercise recovery. The consistency of our data with established models of lactate and VO₂ kinetics reinforces the validity of our experimental design. The integration of extended post-exercise monitoring and bi-exponential modeling provides a comprehensive view of recovery dynamics, offering practical implications for training prescription and fatigue management in sprint athletes. Additionally, the high VO₂peak values (45.4 ± 4.1 ml/kg/min) obtained from our participants demonstrate their elite sprinters’ exceptional aerobic capacity, which complements their anaerobic power. Maintaining dual capacity is crucial for sustaining high-intensity efforts and optimizing performance in sprint events. Our data also show that elite sprinters have a special ability to quickly remove lactate and other metabolic waste products, which is probably due to their high-intensity training programmes29. The ability to recover efficiently between intense exercise sessions is a key factor in athletic performance and overall success. Building upon the research of Bogdanis et al.30, who found similar rapid lactate clearance in elite athletes, it appears that training interventions aimed at enhancing lactate clearance may be advantageous for improving performance, as also suggested by Bogdanis et al.30.

Practical implications

Our research offers a comprehensive understanding of lactate and VO₂ dynamics, which can be used to create customised training regimens that balance anaerobic and aerobic training. These insights enable coaches and athletes to refine their training loads, recovery approaches, and nutritional interventions in order to boost performance and decrease the likelihood of overtraining. Incorporating interval training sessions that replicate the challenges of competition can enhance both anaerobic and aerobic abilities in sprinters. Engaging in low-intensity activities, including cycling or swimming, can aid in lactate removal and improve the recovery process. Carbohydrate and protein supplementation can be used as nutritional interventions to aid in recovery by restoring glycogen levels and facilitating muscle repair.

Future Directions

Future studies should investigate the dynamics of lactate and VO₂ kinetics in various athletic cohorts and training methodologies. Examining the effects of different training interventions, including high-intensity interval training (HIIT) and resistance training, on these physiological responses could offer valuable information for fine-tuning training and recovery procedures. Examining the long-term adaptations to training in elite sprinters through longitudinal studies could provide insight into the mechanisms driving their exceptional performance and efficient recovery. This research could also identify potential biomarkers for monitoring training status and preventing overtraining.

Conclusions

In brief, our research provides significant insights into the metabolic reactions and recovery processes of top-level sprint athletes. The results emphasize the significance of accurate timing in lactate sampling and illustrate the intricate relationship between the anaerobic and aerobic systems during and after intense exercise. Further investigation of these dynamics among various athletic groups and training methods to enhance training and recovery techniques in competitive sports. Enhancing our comprehension of these physiological reactions will enable the creation of more efficient training protocols that improve performance, lower the likelihood of injury, and foster long-term athletic progression.

Conflicts of interest. The authors declare that there is no conflict of interest.

Authors’ contributions. FT: Methodology, Data Collection, Investigation, Data Curation. SHH: Methodology, Conceptualization, Supervision, Writing – Original Draft Preparation, Review & Editing. All authors read and approved the final version of the manuscript

Acknowledgements. During the manuscript revision, an AI-based language model was used to assist with language improvements. The final content has been reviewed and approved by the authors.

Data availability. The dataset presented in this study is available upon request from the corresponding author during submission or after publication (Hootan.shahidi@yahoo.com/ Houtan.shahidi@gedik.edu.tr). However, due to restrictions, the data are not publicly available.

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