Anaerobic Threshold Detection in Soccer Players: A Narrative Review Volume 62- Issue 2

Sergio L Jiménez-Sáiz¹*, Jonathan Panqueva¹, Sergio Jiménez-Rubio¹ and Julio Calleja-González²

• ¹Sport Sciences Research Centre, Universidad Rey Juan Carlos, Spain
• ²Department of Physical Education and Sports, Faculty of Education and Sport, University of the Basque Country, Spain

Received: June 02, 2025; Published: June 23, 2025

*Corresponding author: Sergio L Jiménez-Sáiz, Sport Sciences Research Centre, Universidad Rey Juan Carlos, Madrid, Spain

DOI: 10.26717/BJSTR.2025.62.009712

Abstract PDF

Soccer is a high-intensity, intermittent team sport that requires players to perform sprints, jumps, rapid decelerations, and other demanding actions. These activities necessitate excellent cardiovascular fitness, endurance, and strength. During a 90-minute match, players typically operate at approximately 85% of their maximum heart rate or 75% of their VO2max, though these values vary depending on the player’s position and role. Monitoring the Anaerobic Threshold (AT) is essential in planning soccer training because it helps to evaluate endurance, regulate training loads, and manage fatigue and recovery. Various methods exist to detect AT, including ventilatory thresholds and BLC-based techniques such as Dmax, Log-Log, and the Hoff method. These are implemented in both laboratory and field environments and adapted to individual player fitness levels, nutrition, and training objectives. Running velocity is a key predictor of the Maximal Lactate Steady State (MLSS), a critical marker of the AT. Differences in AT-related performance have been observed across age groups, with older youth players generally exhibiting greater endurance. Positional variations also exist, with goalkeepers displaying lower running velocities than outfield players. External influences, such as fasting during Ramadan, further underscore the multifactorial nature of soccer performance.

In conclusion, detecting the AT remains vital for optimizing soccer performance. By combining BLC and ventilatory assessments with practical field tests, coaches can better monitor and enhance player endurance. The choice of method should be personalized based on age, position, and contextual factors. Future research should focus on refining these tools and promoting non-invasive, cost-effective alternatives that serve both elite and amateur athletes.

Keywords: Soccer; Football; Blood Lactate Concentration; AT; Lactate Threshold; Maximum Lactate Steady State (MLSS)

Abbreviation: AT: Anaerobic Threshold; BLC: Blood Lactate Concentration; MLSS: Maximal Lactate Steady State; LT: Lactate Threshold; VT: Ventilatory Threshold; LE: Lactate Exchange; CVRT: Constant Velocity Running Test; SCT: Second Incremental Test; ET: Exercise Tests; VI: Visual Inspection

Cognitive development progresses along a natural continuum throughout the human lifespan [1,2]. Alongside age- related cognitive decline, various health issues such as hypertension, diabetes mellitus, and cardiovascular disease significantly contribute to a faster deterioration in cognitive function [3-5]. Within anesthesiology, there are apprehensions about how surgery and anesthesia may accelerate cognitive decline [6,7]. This concern is amplified by the aging population’s growing demand for surgical procedures performed under general anesthesia throughout their lives [8]. To understand the impact of anesthesia on cognitive function. A few decades ago, undergoing surgery with anesthesia was considered highly perilous, as the rates of mortality and morbidity related to surgical procedures and anesthesia were alarmingly high [9]. It was often said that a patient did not tolerate anesthesia if perioperative mortality occurred. At that time, surgeries had to be brief to minimize the risks associated with anesthesia. Today, anesthesia is exceptionally safe, with perioperative mortality rates approaching extinction. When such incidents do happen, they tend to make headlines [9]. While we no longer face the same lethal risks from anesthesia, it raises the question: can both anesthesia and surgical procedures have short- and long-term effects on cognitive function? [9].

Soccer is among the most widely practiced sports globally, demanding a combination of aerobic and anaerobic fitness, strength, speed, coordination, and tactical understanding. Performance hinges on both individual technical ability and collective team strategy. Over the years, the sport has evolved significantly through the integration of advanced technologies, scientific insights, and multidisciplinary collaboration. Soccer is classified as a high-intensity intermittent team sport (Bradley, et al. [1]), with player success relying increasingly on cardiovascular endurance and the ability to perform repeated bouts of intense physical activity. Scientific developments have revealed a progression in the physical demands of soccer, especially in high-speed actions such as sprints, accelerations, decelerations, jumps, and direction changes. These activities require players to maintain elevated levels of aerobic capacity and muscular power throughout a match. Aerobic energy metabolism plays a critical role in match performance, and matches are also associated with elevated blood lactate concentrations (Krustrup, et al. [2]). Parameters such as maximal oxygen uptake (VO₂max), Ventilatory Threshold (VT), Lactate Threshold (LT), and BLC are key physiological indicators in soccer performance assessments. Aerobic fitness is essential for professional players, who typically cover 10 to 12 kilometers per match while maintaining an average exercise intensity near 75% of their VO₂max (Cerda-Kohler, et al. [3]).

This underscores the importance of aerobic capacity in energy expenditure and performance. In addition to VO₂max, other biomarkers such as LT and running velocities associated with lactate accumulation provide valuable insights into players’ endurance capabilities (Ziogas, et al. [4]). The capacity to sustain high levels of aerobic and anaerobic fitness allows players to maintain performance levels, recover efficiently, and reduce fatigue-induced declines. Thus, understanding what occurs during anaerobic exertion is vital to optimizing performance. As Erceg, et al. [5]. emphasize, achieving peak physical fitness requires the application of modern sport science and individualized physiological monitoring (Erceg, et al. [5,6]). Anaerobic energy metabolism results in lactic acid accumulation, leading to metabolic acidosis and muscular fatigue, which impairs performance. A deeper understanding of anaerobic glycolysis and its physiological consequences allows for better training strategies aimed at delaying fatigue onset and improving energy efficiency.

The AT, also referred to as the Lactate Threshold (LT), denotes the exercise intensity at which lactate production exceeds clearance, marking a critical physiological transition. This threshold serves as a key biomarker for training prescription and performance monitoring in both clinical and athletic populations (Akubat, et al. [7]). Submaximal blood lactate assessments are valuable tools for detecting endurance fitness changes. (Katz and Sahlin [8]) proposed that lactic acid accumulation during submaximal exercise results from mitochondrial oxygen restriction. BLC and LT are potentially more sensitive indicators of endurance performance than VO₂max alone (McMillan et al., [9,10]). A higher LT indicates a player’s capacity to sustain higher intensities over time. AT detection can be performed via laboratory or field-based protocols. The choice of method depends on resources, player level, and specific goals. Laboratory-based assessments typically involve incremental Exercise Tests (ET) or cardiopulmonary exercise testing (CPET), with stepwise increases in intensity and measurements of VO₂, heart rate, and BLC (Jemni, et al. [11]).

AT is identified as the highest VO₂ or intensity before an increase in BLC >0.5 mmol/L over the previous stage. This inflection point signifies a shift from predominantly aerobic to anaerobic energy production. According to (McMillan et al. [9]), fixed BLC values between 2 and 4 mmol/L are often used to define aerobic endurance training zones. Alternative methodologies for LT determination include:

• Visual Inspection (VI): Lactate values plotted against workload to visually detect a breakpoint in the curve.

• D_max and Modified D_max: Based on the point with the maximum perpendicular distance from a line connecting the extremes of the curve.

• Log-Log Method: A linear regression approach linking log-transformed lactate concentrations and work rate to identify transition points (Cerda-Kohler et al. [3]).

While laboratory tests offer high precision, field-based methods are increasingly used for their practicality and ecological validity. These typically involve portable lactate analyzers and graded exercise protocols adapted to the competitive environment. However, results can be influenced by training phase, environmental conditions, individual variability, and sampling methodology. To ensure reliability, field-based protocols should be validated against gold-standard laboratory tests whenever possible. Despite their limitations, fieldbased assessments are valuable in day-to-day practice. Training near or slightly below the AT has been shown to improve endurance, delay fatigue, and elevate the AT itself. Therefore, it is also crucial to determine the Maximal Lactate Steady State (MLSS), defined as the highest exercise intensity at which BLC remains stable over time. MLSS provides a robust measure of sustainable performance and is a key reference for endurance-based training plans. Training at or near MLSS enhances an athlete’s ability to tolerate higher workloads over prolonged periods, making it especially relevant for soccer players engaging in long-duration, intermittent high-intensity efforts (Goranović, et al., [12]). These physiological principles are foundational for programming, monitoring, and optimizing sports performance. Sports scientists and coaches must develop training strategies that enhance endurance capacity during the competitive season while minimizing the risks of overtraining or suboptimal match performance (McMillan et al. [9]).

Furthermore, exploring strategies to mitigate lactic acid buildup could unlock new avenues for improving physical endurance and overall athletic performance. Continued research in this area holds promise for enhancing both performance and athlete health across multiple disciplines. This narrative review aims to investigate and summarize current evidence and methodologies for detecting AT and Maximal Lactate Steady State (MLSS) based on BLC in soccer players.

This narrative review was based on a comprehensive literature search conducted in the Web of Science, PubMed, and Scopus databases. Search terms included “AT,” “lactate threshold,” “MLSS,” and “soccer.” Studies were selected based on their relevance to the assessment of the AT in soccer players, with no restrictions regarding population characteristics or publication date. Both laboratory-based and field-based methodologies were considered. The most pertinent findings are synthesized in the following sections, including a summary table highlighting key studies and their main outcomes.

(Tables 1 & 2) (Garcia, et al. [13]) examined key factors related to the maximum lactate steady-state velocity (MLSSv) in soccer players. They found that Lactate Exchange (LE) and running velocity were the best single predictors of both individual and group average MLSSv. There were no statistically significant differences between actual MLSS and estimated MLSS using the LEmin prediction formula, suggesting its reliability. LEmin also did not differ significantly from conventional Lactate Thresholds (LTs) (p > .05), although it was found to be 24% lower than MLSS (p < .001). LE was identified as the major determinant of MLSSv, and individual MLSSv values ranged from 11.2 to 16.5 km/h, reflecting wide variability in aerobic fitness among players. These findings underscore the importance of running velocity, the accuracy of the LEmin formula, and the role of LE in understanding MLSSv. (Erceg, et al. [5]) reported significant physiological differences between age groups, with U-17 and U-19 players showing superior values in most variables compared to U-15 players. Significant differences were observed between U-15 and U-17, as well as between U-17 and U-19, with older players outperforming younger ones. Notably, Lrest values in all age groups exceeded physiological norms, likely due to soccer-specific activity. Lmax was higher in U-17 and U-19 than in U-15, although no statistical difference was found between U-17 and U-19. U-19 players had higher pre-test BLC but lower post-exertion BLC than U-17 players, indicating more efficient lactate metabolism. Heart rate at AT was similar across groups, but U-17 and U-19 crossed the threshold later, demonstrating better endurance. U-19 players also exhibited higher minute ventilation (VEvp) and VO₂max, which increased progressively with age, at approximately 1 mL/kg/min per year.

Table 1: Summary of Methodology for Detecting AT, Maximal Lactate Steady State (MLSS) in Soccer Players.

Table 2: Summary of Results (Findings, Discussion/ Limitations, Practical Application in Soccer.

(Cerda-Kohler, et al. [3]) found a lack of agreement among various methods used to assess lactate threshold speed (LTspeed), although more consistent results were observed for lactate threshold heart rate (LTHR). Agreement in LTHR was noted particularly between VI, Dmax, DmaxM, and VI-DmaxM methods, whereas ICC analysis revealed no agreement between LTspeed and LTHR measures. One-way ANOVA showed that LTspeed was significantly higher when assessed with VI, DmaxM, and Dmax compared to the Log-Log method, and higher with VI and DmaxM than Dmax alone. For LTHR, values were significantly higher using VI, DmaxM, and Dmax versus Log-Log, and DmaxM yielded higher values than Dmax. (Parpa et al. [6]) identified differences in speed calculations between VT2 and LT methods, except when using the Log-Log method. Within Group 1, significant differences emerged between VT2 and both Log-Log and FBLA (4 mmol/L) methods, as well as between V1 and Dmax. VI also showed greater agreement with mathematical methods, while Log-Log yielded lower LTspeed and LTHR values. (Loures et al. [14]) found no significant differences between test and retest values for AThoff, AThoff4.0, and AThoffBI, including HR at AT-speed. Significant correlations were observed for AThoff and AThoff4.0, but not for AThoffBI. Additionally, HR AThoffBI and HR AThoff were significantly correlated between test and retest. (Schwesig et al. [15]) reported position-specific differences in lactate threshold performance. Goalkeepers had the lowest velocities at all thresholds (V2: 10.7 ± 1.17 km/h, V4: 14.0 ± 1.06 km/h, V6: 15.5 ± 1.08 km/h), while central midfielders had the highest (V2: 12.5 ± 1.2 km/h, V4: 15.2 ± 1.14 km/h, V6: 16.6 ± 1.13 km/h). Endurance performance in the Wingate Anaerobic Test (WINGS) also differed significantly at all thresholds (V2: p = 0.035; V4: p = 0.047; V6: p = 0.041), though no significant differences were found among field players. (McMillan, et al. [9]) observed increased running velocity at LT (vTLac and V4mM) from pre-season to October, with lower BLC at each velocity. No significant lactate response changes were noted at other testing points. Significant correlations were found between vTLac and V4mM (r = 0.87, p < 0.001), and between heart rate at both thresholds (r = 0.82, p < 0.001).

These improvements were attributed to specific twice-weekly running sessions enhancing running economy. Lastly, (Güvenç, et al. [16]) studied the effects of Ramadan fasting, noting stable body mass, BMI, and fat-free mass throughout. Skinfold thickness decreased, indicating fat loss. Running performance metrics showed initial stability with subsequent improvements post-fasting. However, running velocity at 4.0 mmol/L and peak running performance were lower during and before fasting than afterward. Metabolic and cardiovascular parameters remained stable overall, except for reduced BLC and heart rate at higher intensities post-fasting. These findings offer insights into physiological adaptations to fasting and their effects on soccer-specific performance.

This narrative review aims to identify and critically evaluate the methodologies employed for determining the AT in soccer players, seeking to bridge the theoretical-practical gap in order to optimize athletic performance. By analyzing key studies, methods, and emerging trends, our objective is to determine the most effective approaches for assessing AT in the context of soccer, while highlighting their practical applications. Through a systematic synthesis of available evidence, we aim to provide coaches, athletes, and sports scientists with the tools necessary to enhance soccer performance. (Garcia, et al. [5]) proposed a promising equation (LEmin) for predicting the Maximum Lactate Steady State (MLSS), which demonstrated strong predictive power, explaining 70% of the variance in MLSS values—an improvement over previous models. However, the equation requires further validation across varied populations, including different genders and age groups, to ensure its generalizability. Although onfield tests such as the Constant Velocity Running Test (CVRT) offer practicality, they also present limitations due to day-to-day variability. In a related study, Yaeger et al. (2028) compared two MLSS determination methods in competitive male cyclists and found that the Second Incremental Test (SIT), combined with the Visual Deflection from Baseline (TVis) method, outperformed the traditional VO₂max test, raising concerns about relying on a single incremental test for accurate MLSS assessment. (Erceg, et al. [16]) demonstrated that older players (U-19) exhibit better adaptation to physical demands due to prolonged training exposure, reflected in increased capillarization, mitochondrial density, and aerobic capacity. Resting heart rate and pulmonary efficiency also improved with age. Their findings support the importance of early training intervention in youth and highlight the high cost and limited reproducibility of BLC analysis. In a similar vein, (Güler, et al. [5]) analyzed the effects of aerobic and anaerobic fatigue on balance in young female soccer players, finding that anaerobic fatigue particularly impaired balance and increased injury risk, especially considering sex-based differences.

Both studies underscore the need for individualized training programs that account for age and gender-specific physiological differences, reinforcing the critical role of AT assessment in safe and effective performance optimization. (Cerda, et al. [3]) emphasized the lack of consensus among lactate threshold measurement methods, particularly regarding discrepancies between the Log-Log method and others. This highlights the need for a standardized gold standard. Similarly, Stanisław et al. (2016) studied judo athletes and found significant correlations among several LT determination methods (LT4.0 mmol, LT Log-Log, LT1 mmol), allowing coaches more flexibility when prescribing training intensities, although further research is needed to compare endurance requirements across combat sports. (Parpa, et al. [6]) found significant differences in speed calculations using VT2 and LT methods, except when applying the Log-Log method, which showed greater internal consistency. While VT2 and KT yielded consistent results in both groups, discrepancies emerged within Group 1 between VT2 and Log-Log, and between VT2 and FBLA at 4 mmol/L. The study also confirmed greater agreement between VI and mathematical methods.

Despite its small sample size, it highlighted VT2’s potential as a non-invasive alternative for LT assessment. (Edwards, et al. [17]) compared AT and VO₂max, noting that while both reflect cardiovascular fitness, they are governed by different mechanisms—VO₂max by cardiac output and AT by peripheral muscle metabolism. Importantly, they emphasized the utility of lactate-based assessments as non-invasive and practical tools in sports like soccer, where specific functional testing may offer more relevant information than general thresholds. (Loures, et al. [14,18]) focused on test-retest reliability of LT and MLSS assessments, both confirming the consistency of their respective methods. (Loures, et al. [14]) validated AThoff and AThoff4.0 for endurance training prescription, while Zagatto et al. found strong correlations between soccer-specific testing (e.g., Hoff circuit) and key physiological markers. Their findings support the use of heart rate to guide training, echoing (McMillan, et al. [9]), who recommended HR and LT-based monitoring for optimizing in-season performance. (Schwesig, et al. [15]) revealed positional differences in running velocity and lactate thresholds, with goalkeepers showing significantly lower velocities than midfielders, challenging the assumption of uniform fitness across positions. This contrasts with (Guner et al. [19]), who observed no significant age or position-based differences in young players, though cardiovascular efficiency did improve with age and training. These results highlight the need to individualize training by position and developmental stage. (McMillan, et al. [9]) also reported improvements in running velocity at LT and 4 mmol/L (vTLac and V4mM) from pre-season to October, along with decreased BLC and strong correlations between vTLac, V4mM, and HR, supporting the value of targeted, systematic endurance training protocols.

Lastly, studies by (Güvenç et al. [16, 20]) examined the effects of Ramadan fasting on performance, emphasizing the importance of integrating cultural awareness into sports science. Beyond physiological monitoring, acknowledging athletes’ religious and psychological states is essential for inclusive and effective performance management. Fasting affects not only physical output but also mindset and emotional well-being, necessitating individualized strategies for hydration, recovery, and load management. Respecting such cultural practices fosters athlete-centered coaching and contributes to both physical and mental performance sustainability.

Incorporating the findings from (Garcia et al. [21]), a practical application for soccer coaches and trainers is the adoption of functional, cost-effective alternatives to determine maximal lactate steady-state velocity (MLSSv), notably through the use of the LEmin method, which has been identified as a reliable predictor. This approach reduces the cost and complexity of MLSS assessments, enhancing accessibility for both players and practitioners. By integrating LEmin-based equations into endurance monitoring protocols, coaches can optimize training prescription in a more efficient and personalized manner. These methods also streamline athlete monitoring by providing key insights into endurance capacity, which is essential for developing targeted aerobic training strategies. Moreover, aligning with the insights of (Erceg, et al. [5]), it is crucial to consider physiological differences across age groups when planning training programs. Coaches must tailor workloads and intensities according to players’ developmental stages to maximize adaptation and reduce injury risk. Combining lowcost assessment methods with age-appropriate strategies enhances the precision of endurance evaluation and training planning in youth and senior soccer populations. (Erceg, et al. [5]) further underscore the importance of addressing age and gender when designing training programs. Coaches should implement individualized regimens that account for physiological differences, ensuring safe progression in load, volume, and recovery. AT assessment becomes essential in this context, guiding coaches toward training zones that reflect each player’s actual capacity and reducing the risk of overtraining or injury. Personalized, age- and gender-specific programming supports athlete development and aligns with best practices in long-term athletic preparation. From (Cerda, et al. [3]), it becomes evident that lactate threshold (LT) assessments offer critical insight into endurance performance and can be used to fine-tune pre-season and in-season training loads.

Monitoring LT values allows for adaptive, data-driven coaching that categorizes athletes by physiological profile and enables continuous performance evaluation. Importantly, LT assessment should be part of a broader, multifactorial approach to training that includes technical, tactical, and physical components. (Parpa et al. [6]) emphasize the value of non-invasive methods for identifying physiological thresholds, particularly VT2 or the respiratory compensation point, as practical tools for training and performance assessment. Avoiding invasive procedures increases player comfort and makes threshold detection more feasible in applied settings. Integrating VT2 into routine assessments allows coaches to better understand players’ responses to match and training loads and refine aerobic development strategies accordingly. Similarly, Loures, et al. [14,20] advocate for soccer-specific testing environments, such as the Hoff circuit, which mirror the physiological and tactical demands of real-game conditions. These tests provide accurate fitness assessments and help in planning training interventions that improve match readiness. Their findings support the use of lactate threshold assessments as regular tools in monitoring fitness evolution, enabling fine-tuning of aerobic and interval training, often using heart rate as a control metric. This aligns with (McMillan, et al. [9]), who recommend using fixed lactate zones (e.g., 2–4 mmol/L) for guiding aerobic work and improving running economy via structured interventions such as two-sessionper- week running drills or maximal strength training. (Schwesig et al. [14]) challenge the use of fixed lactate thresholds—like the standard 2 mmol/L—in player monitoring, revealing that playing style and muscle fiber composition can significantly influence lactate dynamics.

Fast-paced players tend to present higher initial lactate values and elevated responses under load, which calls for individualized threshold setting. A one-size-fits-all model may be insufficient; thus, coaches should consider personalized lactate profiles to adapt conditioning programs more accurately. In contrast, Guner, et al. [18] observed no significant differences in running velocity and heart rate by position or age in young players, though improvements in cardiovascular efficiency with age were apparent, reinforcing the role of structured training in long-term development. McMillan, et al. [9] demonstrated that V-Tlac and V-4mM are both valid methods for assessing LT, offering coaches simple and repeatable protocols to build personalized training plans. Emphasis on improving running economy (Cr) through targeted interventions yielded notable performance gains, highlighting the value of ongoing aerobic capacity assessment. The use of blood lactate zones during training provides an effective guide for intensity prescription, facilitating aerobic optimization. Finally, the findings from Güvenç et al. [16,20] point to the importance of cultural sensitivity in athletic performance management, particularly during Ramadan fasting.

Recognizing the cultural and religious practices of players enables support staff to personalize assessments and training modifications with empathy and effectiveness. Strategies should consider individual needs related to nutrition, hydration, sleep, and recovery while respecting athletes’ beliefs and well-being. Cultural competence in coaching fosters a respectful and inclusive environment that supports both physical and psychological performance. In summary, the practical applications derived from this review underscore the importance of integrating individualized, evidence-based, and context-aware strategies for training and performance monitoring in soccer. Coaches and sports professionals are encouraged to combine physiological assessments, such as MLSS, LT, and VT2, with tailored programming that reflects the unique demands of each player—considering age, gender, cultural background, and position—thereby enhancing player development and maximizing on-field performance.

This narrative review underscores the importance of optimizing the determination of the AT in soccer players by identifying the most valid and practical assessment methods. Accurate, individualized, and sport-specific testing protocols are essential to enhance player monitoring and performance development. Variables such as age, gender, and cultural practices (e.g., fasting) must be taken into account when evaluating lactate-related responses. Additionally, the review advocates for the integration of standardized lactate threshold measurement techniques while also encouraging innovation in non-invasive, field-based protocols for endurance monitoring. Gender-sensitive research is particularly needed to refine protocols suited to female soccer players, a demographic historically underrepresented in this domain. Ultimately, advancing our understanding of threshold dynamics through improved methodologies will enable better training decisions and elevate the performance of soccer athletes at all levels [22-25].

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