Kinetic Chain Contribution to Speed and Energy in Karate Techniques

Abstract

Karate emphasizes technical precision, controlled movement, and the integration of strength and speed. Understanding the relationship between athletic performance and mechanical energy is essential for refining techniques. This study quantifies kinetic energy during mae geri (front kick) and gyaku tsuki (reverse punch) in elite and sub-elite athletes. Fourteen male black-belt karate athletes were divided into two groups: elite (n = 7) and sub-elite (n = 7). Physical attributes and muscular strength were assessed using isokinetic evaluations, while striking performance was analyzed through synchronized kinematic systems to measure linear and rotational kinetic energy at key joints. No differences in dynamometric strength were found between groups. However, elite athletes showed superior peak kinetic chain output, achieving higher peak velocities and kinetic energy in both techniques. For mae geri, elite athletes showed higher peak velocity (9.5 ± 0.8 vs. 8.5 ± 0.8 m·s⁻¹; p = 0.001) and kinetic energy (155.86 ± 54.06 vs. 124.42 ± 34.13 J; p = 0.012). In gyaku tsuki, elite athletes reached faster peak velocities (7.3 ± 0.8 vs. 6.1 ± 0.7 m·s⁻¹; p = 0.001) and kinetic energy (269.57 ± 18.62 vs. 214.44 ± 9.27 J; p = 0.008). These findings highlight the importance of peak kinetic chain output in karate.

1. Introduction

Karate as a combat sport prioritizes technical precision, emphasizing speed, accuracy, and control in execution [1,2,3,4]. Nevertheless, strength remains essential, as its integration with precision enhances strike efficiency by maximizing force output without compromising technical execution [5]. This balance is particularly evident in kumite, where athletes compete in controlled-contact combat, permitting facial touches and full-force strikes to the trunk, showcasing techniques executed with remarkable speed and power [6]. While regulations permit maximum force when targeting the torso, contact with the head is restricted to ensure safety. Nonetheless, strength plays an important role in kumite, as scoring points relies on executing fast and powerful techniques that maximize the velocity of distal segments (hand or foot) in synergy with applied force [7]. The relative contribution of velocity versus force to successful techniques, however, remains an open question, as both factors interact within the kinetic chain.

The kinetic chain provides the foundation for coordinated, sequential human movement, facilitating the efficient transfer of energy across body segments [8]. In a closed kinetic chain, the distal extremities remain stationary, facilitating coordinated body movement. Conversely, in an open kinetic chain, the distal extremities move freely, contributing to the accumulation of kinetic energy output in each segment [8,9,10]. These principles are fundamental in tasks requiring precise coordination between strength and postural control, such as soccer kicks [10,11], baseball pitching [12], tennis serving [13], and striking in combat sports [14,15].

In karate, techniques such as gyaku tsuki (reverse punch) and mae geri (front kick) are applied and hold strategic importance in competitions [16,17]. The mae geri is inherently a ballistic movement aimed at striking the opponent’s body or a target using the foot [18,19]. Its effectiveness lies in the swift execution of the technique, particularly in competitive settings where time and space constraints limit the opponent’s ability to anticipate it. This attack requires a dynamic sequence of movements involving the trunk, spine, knee, ankle, and foot, generating a synergy extending from the spine to the foot due to the neuromuscular activation of the lower limb [18].

On the other hand, the gyaku tsuki is a punch executed with the arm opposite the leading leg, aiming to strike at medium range [20]. This technique initiates in the lower extremities, transferring energy through the legs and torso to the shoulder, culminating in the striking arm [21]. According to the principle of the kinetic link, joint movements occur sequentially, reaching maximum velocity at each distal joint, surpassing that of the preceding proximal joint [15,20].

Understanding these biomechanical processes is critical for the development of more effective training programs, as optimizing energy transfer along the kinetic chain distinguishes technically proficient execution from suboptimal performance. Previous studies [14] have identified significant differences in coordination patterns between elite and sub-elite athletes. One commonly used metric to assess this is the continuous relative phase (CRF), which measures how synchronized different joints are during movement by analyzing their angular positions and velocities. Elite athletes typically exhibit lower CRF values, indicative of more synchronized and efficient movement patterns, whereas sub-elite athletes demonstrate higher CRF values along with increased variability in coordination. This reduced variability of intersegmental coordination in elite athletes likely contributes to energy transfer throughout the kinetic chain, enabling them to generate higher linear velocities in distal segments, such as the hand and foot, while maintaining technical precision [22,23]. While CRF provides valuable insights into coordination, it does not directly quantify the mechanical output generated by these movements, which is critical for understanding actual performance differences [15,18].

Quantifying the kinetic energy output through both linear and rotational displacements is essential for a comprehensive understanding of the biomechanical mechanisms underlying athletic movements. Such analyses provide valuable insights into the relationships between athletic performance and mechanical energy output, emphasizing the importance of efficient segmental coordination over sheer force generation. While the current study focuses on kinetic energy, complementary evaluations of strength using dynamometric assessments would further elucidate its interplay with velocity in the production of force. In this context, the present study proposed a novel method for quantifying the kinetic energy output associated with the execution of mae geri and gyaku tsuki and examined its characteristics in elite and sub-elite karate athletes. The working hypothesis posits that elite athletes would generate higher total kinetic energy values than their sub-elite counterparts, not due to superior force production but through a more efficient summation of segmental contributions within the kinetic chain. This efficiency may underlie their superior technical proficiency and competitive outcomes.

2. Materials and Methods

2.1. Sample

This study recruited 14 male karate athletes aged 18 to 35 years, classified into two groups based on competitive level: the elite group (7 black belt athletes competing at national or international levels; age: 26.3 ± 6.9 years; body mass: 77.5 ± 12.8 kg; height: 1.71 ± 0.08 m; body fat percentage: 12.6 ± 6.7%) and the sub-elite group (7 black belt athletes competing at regional or state levels; age: 27.5 ± 6.1 years; body mass: 75.1 ± 8.9 kg; height: 1.71 ± 0.06 m; body fat percentage: 15.1 ± 5.9%). Regarding anthropometry, the following measurements were taken: body mass, height, and skinfold thickness at the chest, abdomen, and thigh [24]. These were used to calculate body fat percentage [25].

All participants had a minimum of five years of continuous karate practice, with training frequencies ranging from four to six sessions per week, and were actively competing in official events at the time of data collection. To ensure an adequate sample size, a priori power analysis was conducted using G*Power software (version 3.1.9.2), which estimated that at least 12 athletes (6 per group) were required to detect differences between groups with 80% power and an effect size ranging from 0.5 to 0.8, considering α = 0.05 and four key study variables. Accordingly, the inclusion of 14 athletes provided sufficient statistical power for the analyses.

Exclusion criteria included recent pain, fractures, or severe soft tissue injuries within the past six months, as well as a history of cognitive, neurological, cardiovascular, or respiratory conditions. These criteria were assessed through a pre-evaluation interview. The study received approval from the Ethics Committee of São Paulo State University—Júlio de Mesquita Filho, Rio Claro Campus (CEP Nº 036/2013) and all participants provided written informed consent.

2.2. Dynamometric Assessment

The upper limbs dynamometric evaluation was performed using the Biodex System 4 Pro dynamometer (Biodex Medical Systems, Shirley, NY, USA), equipped with shoulder- and elbow-specific accessories aligned with joint centers according to the manufacturer’s specifications. Before initiating the testing protocol, participants underwent a familiarization session consisting of three submaximal and two maximal actions for each joint assessed [26]. Isokinetic concentric actions were measured at velocities of 60°/s, 180°/s, and 240°/s, with a range of motion of 120° (−30° to 90°) for the shoulder joint and 0° to 120° for the elbow joint.

Similarly, hip and knee joints were evaluated using accessories adjusted to the respective joint centers per manufacturer guidelines. Familiarization was executed in the same way of upper limbs. Isokinetic concentric actions were assessed at 60°/s, 180°/s, and 240°/s, with a range of motion of 60° (0° to 60°) for the hip joint and 90° (0° to 90°) for the knee joint. The sequence of joint testing was randomized, and five repetitions of flexion and extension movements were performed at the designated velocity.

2.3. Strikes Assessment

Strikes play a crucial role in karate. Gyaku tsuki was selected due to its high frequency in competitive bouts [17], representing typical upper-limb striking actions, while mae geri, a fundamental kicking technique, was included because it serves as a foundational kick that underpins the execution of more complex movements and enables differentiation between upper- and lower-limb movement patterns. Both strikes were executed unilaterally with the dominant lower limb in response to visual stimuli from an LED system located on the target. The instrumented target was equipped with blue and red LEDs to signal stimuli for gyaku tsuki and mae geri, respectively, and a contact sensor composed of a 24 cm × 27 cm ethylene-vinyl acetate block integrated with a 30 mm piezoelectric sensor, which recorded the exact moment of contact.

The LED system and contact sensor were controlled by an Arduino MEGA 2560 (Arduino LLC, Milan, Italy), ensuring precise synchronization of the visual cues and contact detection. Participants placed their dominant lower limb foot on a pre-marked spot, and the signals from the instrumented target were synchronized through an analog input to the Vicon^® motion analysis system (Vicon Motion Systems Ltd., Oxford, UK) to capture data simultaneously across both systems.

A certified referee from the São Paulo Karate Federation validated each strike, instructing athletes to stop, return to the starting position, and continue with the protocol. Kinematic data were continuously recorded throughout the procedure, with each participant performing five attempts of mae geri and five of gyaku tsuki in a non-consecutive order. To ensure reliability and reduce intra-individual variability, the five attempts were averaged, providing a single representative value per technique and participant for the subsequent statistical analysis. Additionally, kinematic data were collected throughout the entire evaluation procedure for both strikes.

2.4. Kinematic

Kinematic data were collected during the execution of strikes using seven T10 cameras (Vicon Motion Systems Ltd., Oxford, UK) operating at a capture rate of 250 fps with reflective markers 14 mm in diameter and processed with Vicon Nexus software (Vicon Motion Systems Ltd., Oxford, UK) for tridimensional analysis of displacements and linear and angular velocities. Bilateral markers were positioned on specific anatomical landmarks based on the PluginGait model (Vicon Motion Systems Ltd., Oxford, UK) for full-body motion analysis. Using the Vicon^® system and PluginGait model, it was possible to analyze displacements and linear and angular velocities of the upper and lower limbs, as well as the power output of these limbs and the displacement of the center of gravity during the evaluated strikes.

2.5. Data Processing and Analysis of Kinetic Chain

The data were subjected to a residual analysis [27] to determine the optimal cutoff frequencies. Dynamometric data were filtered using a 4th-order recursive low-pass Butterworth filter with a cutoff frequency of 8 Hz and then normalized to body mass, while kinematic data were filtered with a similar 4th-order recursive low-pass Butterworth filter, but with a cutoff frequency of 6 Hz. All data were processed and analyzed using specific routines developed in MATLA B (version 8.0.0.783, MathWorks^®, Natick, MA, USA).

The behavior of the kinetic chains during the execution of the mae geri and gyaku tsuki punches was analyzed by calculating the kinetic energy output during specific movements. For the mae geri, the linear displacement of the center of gravity, as well as hip flexion and knee extension, were evaluated. For the gyaku tsuki, the linear displacement of the center of gravity, shoulder flexion, and elbow extension were examined. The relative masses of the body segments involved in these movements were determined using the segmental relative mass method proposed by de Leva. [28]. The total kinetic chain ${KE}_{MG}$ was calculated as the sum of the kinetic energy output by the kinetic energy produced by the anteroposterior linear displacement of the center of gravity ${KE}_{cg}$, hip flexion ${KE}_h$ and knee extension ${KE}_k$, as shown in Equation (1):

$${KE}_{MG}={{KE}_{cg}+KE}_h+{KE}_k$$

(1)

The kinetic energy produced by hip flexion was determined using Equation (2):

$${KE}_h={\displaystyle \frac{1}{2}}\left(I_h{\omega }_{R_c}^2\right)$$

(2)

where $I_h$ represents the moment of inertia of the system driven by the hip, calculated using Equation (3):

$$I_h=m_{thigh+leg+foot}{R}_c^2$$

(3)

The angular velocity of the hip-driven system ${\omega }_{R_c}$ was the sum of the angular velocity of the hip ${\omega }_h$ and the angular velocity corresponding to the radius of rotation ${\omega }_c$, as described in Equation (4):

$${\omega }_{R_c}={\omega }_h+{\omega }_c$$

(4)

The radius of rotation $R_c$ was calculated geometrically using Equations (5) and (6) (Figure 1):

$$R_c=c$$

(5)

$$c^2=a^2+b^2-2ab\mathit{cos}\theta$$

(6)

The kinetic energy output by knee extension ${KE}_k$ was calculated using Equation (7):

$${KE}_k={\displaystyle \frac{1}{2}}\left(I_k{\omega }_k^2\right)$$

(7)

where ${\omega }_k$ is the angular velocity of the knee and I_k is the moment of inertia of the system driven by the knee, calculated as Equation (8):

$$I_k=m_{leg+foot}{R}_k^2$$

(8)

The total kinetic chain ${KE}_{GT}$ of the gyaku tsuki was calculated as the sum of the kinetic energy output by the anteroposterior linear displacement of the center of gravity ${KE}_{cg}$, shoulder flexion ${KE}_s$, and elbow extension ${KE}_e$, as shown in Equation (9):

$$I_k=m_{leg+foot}{R}_k^2$$

(9)

Here, ${KE}_{GT}$ represents the total kinetic energy of the gyaku tsuki. ${KE}_{cg}$ refers to the kinetic energy output by the anteroposterior linear displacement of the center of gravity, ${KE}_s$ represents the kinetic energy output by shoulder flexion, and ${KE}_e$ corresponds to the kinetic energy output by elbow extension.

The kinetic energy output by the anteroposterior displacement of the center of gravity ${KE}_{cg}$ was determined using Equation (10):

$${KE}_{cg}={\displaystyle \frac{1}{2}}\left(m_t{v}_{cg}^2\right)$$

(10)

where $m_t$ denotes the total body mass and $v_{cg}$ represents the anteroposterior linear velocity of the center of gravity.

The kinetic energy output by shoulder flexion, ${KE}_s$, was calculated as described in Equation (11):

$${KE}_s={\displaystyle \frac{1}{2}}\left(I_S{\omega }_{R_S}^2\right)$$

(11)

where $I_s$ represents the moment of inertia of the system driven by the shoulder, calculated using Equation (12):

$$I_s=m_{ua+fa+hand}{R}_s^2$$

(12)

Here, $m_{ua+fa+hand}$ refers to the sum of the masses of the upper arm, forearm, and hand, and $R_s$ corresponds to the radius of rotation of the system driven by the shoulder. $R_s$ was geometrically determined using Equations (13) and (14) (Figure 2):

$$c^2=a^2+b^2-2ab\mathit{cos}\theta$$

(13)

$$R_s=c$$

(14)

The angular velocity of the shoulder-driven system ${\omega }_{R_S}$ was calculated as the sum of the angular velocity of the shoulder ${\omega }_S$ and the velocity induced by the radius of rotation ${\omega }_c$, as described in Equation (15):

$${\omega }_{R_S}={\omega }_S+{\omega }_c$$

(15)

The kinetic energy output by elbow extension ${KE}_e$ was determined using Equation (16):

$${\omega }_{R_S}={\omega }_S+{\omega }_c$$

(16)

where ${\omega }_E$ is the angular velocity of the elbow and $I_E$ represents the moment of inertia of the system driven by the elbow, calculated using Equation (17):

$${\omega }_{R_S}={\omega }_S+{\omega }_c$$

(17)

where $m_{ab+hand}$ denotes the sum of the masses of the forearm and hand, and $R_E$ corresponds to the radius of rotation of the system driven by the elbow, which was equivalent to the length of the forearm and hand.

2.6. Coefficient of Correlation

The linear relationship between the total kinetic energy curve and the time series of linear velocity for each distal segment (foot for mae geri and hand for gyaku tsuki) was assessed using the Pearson correlation coefficient, as shown in Figure 3. The following guidelines for interpreting correlation strength are used in sports science: 0.00–0.19 (very weak), 0.20–0.39 (weak), 0.40–0.59 (moderate), 0.60–0.79 (strong), and 0.80–1.00 (very strong) [29].

2.7. Statistical Analysis

Data normality was assessed using the Shapiro–Wilk test. Descriptive statistics were reported as mean and standard deviation for parametric data, and as median and interquartile range for non-parametric data. Three variables were evaluated: peak total maximum kinetic energy (PKE), peak velocity, and the coefficient of correlation. All variables have shown normal distribution with exception of correlation coefficient between the total kinetic chain and linear velocity of the wrist in the gyaku tsuki execution. The parametric data have been compared using independent Student’s t-tests and the non-parametric data with the Mann–Whitney U test. Additionally, effect sizes were reported using Cohen’s d, with the following scale: d < 0.2 (small effect), 0.2 ≤ d < 0.5 (moderate effect), and d ≥ 0.8 (large effect). For non-parametric data, the effect size r was calculated following Rosenthal’s r, and subsequently transformed into Cohen’s d. All statistical analyses were performed using IBM SPSS Statistics version 18 (IBM Corp., Armonk, NY, USA). A significance level of p < 0.05 was adopted for all statistical tests.

3. Results

No significant differences were found between elite and sub-elite athletes in isometric or isokinetic tests. Across all joints (elbow, shoulder, hip, and knee), descriptive values were similar between groups, with mean torques ranging from 0.92 ± 0.18 to 2.84 ± 0.64 N·m·k.g⁻¹ for isometric tests and 0.56 ± 0.10 to 3.18 ± 0.71 N·m·kg⁻¹ for isokinetic tests, all comparisons yielding non-significant results (p = 0.37–0.51), as illustrated in Figure 4.

In contrast, kinetic chain analyses comparing mae geri and gyaku tsuki in elite and sub-elite karate athletes are presented in

Table 1. Kinetic chain analysis of mae geri and gyaku tsuki in elite and sub-elite karate athletes.

Techniques	Variable	Sub-Elite	Elite	p-Value	Cohen’s d
Mae geri	Peak kinetic energy (J)	124.4 ± 34.13	155.9 ± 54.06	0.012 *	−0.70
	Peak velocity (m·s−1)	8.5 ± 0.8	9.5 ± 0.8	0.001 *	−1.25
	Coefficient of correlation	0.72 ± 0.13	0.83 ± 0.06	0.001 *	−1.03
Gyaku tsuki	Peak kinetic energy (J)	214.4 ± 9.27	269.6 ± 18.62	0.008 *	−0.76
	Peak velocity (m·s−1)	6.1 ± 0.7	7.3 ± 0.8	0.001 *	−1.60
	Coefficient of correlation	0.79 (0.14)	0.88 (0.12)	0.002 *	−0.77

Mean ± SD: mean and standard deviation; J: joules; Cohen’s d: effect size; mae geri: front kick; gyaku tsuki: reverse punch; p-value < 0.05: indicates statistically significant difference between groups, *: denotes statistically significant difference between elite and sub-elite groups.

. Significant differences were found between the groups, with elite athletes displaying higher values of PKE and peak velocity, and all correlation were significant for both techniques (p < 0.05).

4. Discussion

The aim of this study was to compare the kinetic energy output during the execution of mae geri and gyaku tsuki techniques between elite and sub-elite karate athletes. It was hypothesized that elite athletes would exhibit superior total kinetic energy values, reflecting their advanced technical and biomechanical competencies without presenting more torque. The findings revealed significant differences in peak kinetic energy, linear velocity, and the correlation coefficient between these variables, supporting the initial hypothesis. These results emphasize that the competitive advantage of elite athletes is rooted in their greater energy transfer along the kinetic chain, indicative of superior intersegmental coordination and technical refinement [8,9,10,30]. However, the influence of force application, alongside velocity, warrants further exploration, as its contribution to the observed kinetic energy differences remains unclear. Additionally, the behavior of the velocity curve shows a strong relationship with the ability to manage the kinetic chain; the greater this relationship, the higher the velocity achieved. This highlights how managing the kinetic chain has a direct impact on performance.

The absence of significant differences in isometric and isokinetic torque tests between the two groups suggests that maximum muscular torque alone is not the sole determinant of competitive performance in karate. Instead, the ability to apply this strength in a coordinated manner within the kinetic chain appears to be crucial. This finding aligns with the work of Kanakapura et al. [31] who emphasized the importance of technical skill in maximizing athletic performance. While Sbriccoli et al. [4] reported higher absolute torque in knee flexion among elite athletes compared to amateurs, these differences probably appeared due to the larger performance gap. In contrast, our study, focusing on elite versus sub-elite athletes, suggests that the differentiating factor lies in the ability to integrate strength within dynamic movement patterns, particularly in ballistic actions such as kicks and punches. The role of knee flexion in eccentric control and deceleration during these movements is particularly relevant, underscoring the importance of dynamic strength and coordination over isolated maximum torque.

Elite athletes demonstrated significantly higher peak velocities in both techniques analyzed (i.e., mae geri and gyaku tsuki). These results align with findings by Cesari & Bertucco [32], who reported notably greater mean forearm velocities in experienced athletes compared to novices during the execution of gyaku tsuki, as well as with observations by Pozo et al. [19], who reported that international-level karate athletes outperformed their national counterparts in velocity, particularly in the execution of mae geri. These findings underscore the critical role of speed as a technical attribute in karate, serving as a key differentiator across performance levels. The superior velocity achieved by elite athletes likely reflects their optimized intersegmental coordination, which minimizes energy dissipation and enhances the efficiency of explosive movements. This capacity to execute rapid and precise actions emerges as a fundamental predictor of competitive success [33].

In terms of peak kinetic energy, elite athletes demonstrated significantly higher values in both techniques. For mae geri, peak kinetic energy values were notably higher in the elite group, while for gyaku tsuki, the differences were also significant. These findings suggest that elite athletes not only generate more energy but also use it more efficiently, likely due to better segmental synchronization and superior technical ability. This observation aligns with the findings of Goethel et al. [14], who reported that elite athletes displayed greater intersegmental coordination, measured through continuous relative phase metrics, during strike execution. The stability of coordinative patterns in elite athletes underscores the intimate relationship between technical refinement and performance outcomes. This reinforces the potential of kinetic chain metrics, including peak kinetic energy, as reliable predictors of athletic performance.

The correlation we found between peak kinetic energy and movement velocity shows the biomechanical advantage of elite athletes in executing techniques such as mae geri and gyaku tsuki. This relationship highlights a more efficient energy transfer to movement velocity, facilitated by advanced neuromuscular control and specialized motor strategies, hallmarks of elite athletic performance [34]. Supporting evidence from Haugen et al. [35] further demonstrates that elite athletes exhibit highly optimized force–velocity profiles tailored to the specific demands of their disciplines, enabling precise and efficient motor execution. Taken together, these findings show that turning output energy into movement velocity is both a marker of biomechanical advantage and a sign of the refined motor control typical of elite athletes.

This study present limitations that should be considered when interpreting its findings. The analysis focused solely on the mechanical energy exchange between joints and segments, excluding muscle activation, a factor in energy transfer. The sample’s highly specific technical profile resulted in a small size, necessitating the inclusion of all available attempts in the statistical analysis. The inclusion criteria did not account for factors such as technical preference or frequency of technique usage in competition. Furthermore, the techniques were performed in a controlled laboratory setting and from a static position, limiting their applicability to the dynamic and multifactorial conditions of competition. Additionally, the isokinetic tests used induced angular velocities much slower than those observed in sport-specific movements, and the non-specificity of the equipment may not fully replicate karate techniques. Despite these limitations, the study highlights the importance of kinetic energy in execution speed, offering valuable insights for distinguishing elite athletes from sub-elite counterparts and guiding performance development in karate.

The results obtained have practical implications for training and technical preparation in karate. Identifying differences in kinetic energy not only enables the design of more specific and tailored training programs but also helps minimize injury risk by optimizing movement patterns [8,9,19]. Accordingly, training programs should emphasize the execution of coordinated and explosive actions that enhance energy transfer across the kinetic chain. Furthermore, these biomechanical variables can serve as discriminative criteria to differentiate elite from sub-elite athletes, while the monitoring of peak kinetic energy and movement velocity offers an objective tool for performance evaluation and talent identification. Consequently, longitudinal research should explore the effectiveness of training protocols focused on optimizing intersegmental coordination and technical execution, with the aim of advancing both competitive performance and athlete safety.

5. Conclusions

Although no significant differences in maximal torque were observed between elite and sub-elite karate athletes, elite athletes demonstrated superior biomechanical and technical efficiency in executing key techniques. Specifically, peak kinetic energy, movement velocity, and their interdependence emerged as possibly indicators of competitive performance, providing a criterion to differentiate performance levels. These findings expand current knowledge by emphasizing that success in karate does not depend on maximum strength alone, but rather on the ability to integrate this strength into coordinated and efficient technical patterns. Furthermore, the analysis suggests that execution velocity and peak kinetic chain output represent critical determinants of high-level performance, surpassing the role of isolated torque values.