Agreement Between Maximal Lactate Steady State and Critical Power in Different Sports: A Systematic Review and Bayesian's Meta-Regression.

ABSTRACT: Borszcz, FK, de Aguiar, RA, Costa, VP, Denadai, BS, and de Lucas, RD. Agreement between maximal lactate steady state and critical power in different sports: A systematic review and Bayesian's meta-regression. J Strength Cond Res 38(6): e320-e339, 2024-This study aimed to systematically review the literature and perform a meta-regression to determine the level of agreement between maximal lactate steady state (MLSS) and critical power (CP). Considered eligible to include were peer-reviewed and "gray literature" studies in English, Spanish, and Portuguese languages in cyclical exercises. The last search was made on March 24, 2022, on PubMed, ScienceDirect, SciELO, and Google Scholar. The study's quality was evaluated using 4 criteria adapted from the COSMIN tool. The level of agreement was examined by 2 separate meta-regressions modeled under Bayesian's methods, the first for the mean differences and the second for the SD of differences. The searches yielded 455 studies, of which 36 studies were included. Quality scale revealed detailed methods and small samples used and that some studies lacked inclusion/exclusion criteria reporting. For MLSS and CP comparison, likely (i.e., coefficients with high probabilities) covariates that change the mean difference were the MLSS time frame and delta criteria of blood lactate concentration, MLSS number and duration of pauses, CP longest predictive trial duration, CP type of predictive trials, CP model fitting parameters, and exercise modality. Covariates for SD of the differences were the subject's maximal oxygen uptake, CP's longest predictive trial duration, and exercise modality. Traditional MLSS protocol and CP from 2- to 15-minute trials do not reflect equivalent exercise intensity levels; the proximity between MLSS and CP measures can differ depending on test design, and both MLSS and CP have inherent limitations. Therefore, comparisons between them should always consider these aspects.

Comparison of NIRS exercise intensity thresholds with maximal lactate steady state, critical power and rowing performance.

This study aimed to compare the intensity of deoxygenated haemoglobin concentration ([HHb]) and tissue saturation index (TSI) breakpoints ([HHb]-BP and TSI-BP) with maximal lactate steady state (MLSS) and critical power (CP), and to describe their association with 2000-m rowing ergometer performance. Fourteen male rowers performed on a rowing ergometer: I) a discontinuous incremental test with 3-min stages (INC3); II) a continuous incremental test with 1-min stages (INC1); III) constant workload tests to determine MLSS; and IV) performance tests of 500 m, 1000 m, 2000 m and 6000 m to determine CP.CP (257 ± 39 W; 3.79 ± 4.1 L · min-1) was higher than [HHb]-BP3 (205 ± 26 W; 3.48 ± 2.9 L · min-1), [HHb]-BP1 (207 ± 27 W; 3.27 ± 3.2 L · min-1), and TSI-BP3 (218 ± 31 W; 3.51 ± 3.0 L · min-1), but not higher than TSI-BP1 (222 ± 34 W; 3.43 ± 3.2 L · min-1). MLSS (187 ± 26 W; 3.33 ± 3.2 L · min-1) was lower than TSI-BP3 and TSI-BP1 for power output, but not different in any comparison for ⩒O2. The limits of agreement for power output and ⩒O2 suggest poor agreement among these thresholds. The low level of agreement compromises the use of [HHb]-BP and TSI-BP for estimating MLSS and CP; therefore, these thresholds should not be considered interchangeable.

Ketogenic diets, exercise performance, and training adaptations.

PURPOSE OF REVIEW: The ketogenic diet has been proposed as a nutritional strategy in sports. This review was undertaken to provide an overview of the recent literature concerning the effects of ketogenic diet on exercise performance and training adaptations. RECENT FINDINGS: Most recent literature on the ketogenic diet and exercise performance showed no beneficial effects, especially for trained individuals. During a period of intensified training, performance was clearly impaired during the ketogenic intervention, while a diet with high carbohydrates maintained physical performance. The main effect of the ketogenic diet resides in metabolic flexibility, inducing the metabolism to oxidize more fat for ATP resynthesis regardless of submaximal exercise intensities. SUMMARY: The ketogenic diet is not a reasonable nutritional strategy, as it has no advantage over normal/high carbohydrate-based diets on physical performance and training adaptations even when used only in a specific training/nutritional periodization stage.

Effects of the ketogenic diet on performance and body composition in athletes and trained adults: a systematic review and Bayesian multivariate multilevel meta-analysis and meta-regression.

This systematic review with meta-analysis aimed to determine the effects of the ketogenic diet (KD) against carbohydrate (CHO)-rich diets on physical performance and body composition in trained individuals. The MEDLINE, EMBASE, CINAHL, SPORTDiscus, and The Cochrane Library were searched. Randomized and non-randomized controlled trials in athletes/trained adults were included. Meta-analytic models were carried out using Bayesian multilevel models. Eighteen studies were included providing estimates on cyclic exercise modes and strength one-maximum repetition (1-RM) performances and for total, fat, and free-fat masses. There were more favorable effects for CHO-rich than KD on time-trial performance (mode [95% credible interval]; -3.3% [-8.5%, 1.7%]), 1-RM (-5.7% [-14.9%, 2.6%]), and free-fat mass (-0.8 [-3.4, 1.9] kg); effects were more favorable to KD on total (-2.4 [-6.2, 1.8] kg) and fat mass losses (-2.4 [-5.4, 0.2] kg). Likely modifying effects on cyclic performance were the subject's sex and VO2max, intervention and performance durations, and mode of exercise. The intervention duration and subjects' sex were likely to modify effects on total body mass. KD can be a useful strategy for total and fat body losses, but a small negative effect on free-fat mass was observed. KD was not suitable for enhancing strength 1-RM or high-intensity cyclic performances.

What Do We Know about Frame Running? A Narrative Review.

ABSTRACT: This narrative review aims to provide a general overview of the literature about frame running, which is a recent modality of Para-Athletics. Frame running is practiced by using a tricycle without pedals called PETRA RaceRunner, by people with moderate to severe cerebral palsy and other lower limb functional limitations. Briefly, the movement pattern is very similar to walking and running. This review includes studies from scientific databases and content of official sports web sites by using the keywords "framerunning," "racerunning," and "petra racerunning." According to our search, this narrative review highlighted three themes involving the practice of frame running, namely health and quality of life, sports classification, and training and testing in the frame running context.

Determination of the speed-time relationship during handcycling in spinal cord injured athletes.

This study aimed to determine the critical speed (CS) and the work above CS (D') from three mathematical models of para-athletes during a treadmill handcycling exercise. Nine hand-cyclists with spinal cord injuries performed a maximal incremental handcycling test and three tests to exhaustion at a constant speed to determine the speed-time relationship. The three tests to exhaustion were performed at intensities between 90% and 105% of peak speed derived from the incremental test. Then, the determination of CS and D' was modelled by linear and hyperbolic models. CS and D' did not present any significant differences among the three mathematical models. Low values in the standard error of estimate for CS were found for the three models (Linear: Distance-time: 1.7 ± 0.5%; Linear: Speed-1/time: 3.0 ± 1.9% and Hyperbolic: 1.2 ± 0.6%). Based on the simplicity to calculate, the CS modelled by linear-distance-time can be a practical method for handcyclist coaches.

A novel treadmill protocol for uphill running assessment: the incline incremental running test (IIRT).

This study aimed to compare the maximal and submaximal aerobic parameters between two incremental running tests, one being horizontal and the other an incline-based test, namely the incline incremental running test (IIRT). Twenty endurance-trained trail runners completed two incremental treadmill tests, until exhaustion. The first test was performed using an incline of 1%, with speed increments. Then, the IIRT was performed with the speed set at 50% of the peak speed obtained during the previous test, and the incline was incremented. Cardiorespiratory measurements and blood lactate concentration ([La]) were assessed. The mean peak workload from the horizontal test was 17.6 ± 1.4 km.h-1 and peak workload from IIRT was 17.3 ± 1.3% of incline. The VO2peak and [La]peak were not significantly different between the protocols. However, the HRpeak was significantly lower at IIRT. In conclusion, most of the maximal and submaximal aerobic indices showed no differences between the incremental tests analysed. The exceptions were the HRpeak and HR at the lactate turnpoints, that were lower, and the peak O2 pulse that was greater for the IIRT. Taken together, these data support the validity of the IIRT as a specific test for the physiological assessment of runners involved with uphill performances.

Game Running Performance and Fitness in Women's Futsal.

The study aimed to verify possible associations between game-play running performance and outcomes derived from fitness (running) tests in female futsal players. Sixteen women professional elite futsal players from a 1st division league team (19.2±2 years-old, 4.3±2.1 years of experience) participated. Firstly, a graded incremental treadmill test was adopted to determine maximal oxygen uptake (VO2max). Following 72 h of laboratory protocol, players were asked to perform a repeated-sprint test on a court (8×40 m with two 180° change-of-directions). Twenty-four hours after, players participated in a one-off friendly game (two 20-min half-times). A computerized automatic image recognition software (DVIDEOW; 30 Hz) allowed to determine game running performance variables. Fatigue index and best time in the court test and VO2max and its attached speed derived from laboratory-based test showed significant moderate-to-moderately high correlations (r=- 0.59-0.76; p<0.05) with some game running performance outputs, notably related to high-intensity running. In conclusion, the present study provided initial evidence on associations between two fitness tests and one-off game running performance in female futsal. Information derived from the work potentially help conditioning professionals working with female futsal athletes gain awareness about some properties of common testing tools.

Predicting Maximal Lactate Steady State from Carminatti's Shuttle Run Test in Soccer Players.

The objective of the present study was to determine the validity of Carminatti's shuttle run incremental test-T-Car derived parameters in estimating the maximal lactate steady state determined in shuttle run format. Eighteen soccer players performed a T-Car test, and several trials to determine the maximal lactate steady state. From T-Car were derived the heart rate deflection point, peak speed, maximal heart rate and parameters resulting from percentage of peak measures. The validity was accessed by Bland-Altman plots, linear regressions, and two one-sided tests of equivalence analysis. The results showed the speed at 80.4% of T-Car peak speed, the heart rate deflection point and the 91.4% of maximal heart rate were equivalent to maximal lactate steady state (Mean difference; ±90% compatibility interval; -0.8; ±1.5%, -0.4; ±1.1%, and 0.0; ±2.7%, respectively). Additionally, peak speed during the T-Car test was a stronger predictor of maximal lactate steady state (MLSS [km/h]=2.57+0.65 × sPeak; r=0.82 [90% CI; 0.62-0.92], standard error of the estimate=3.6%; 90% CI ×/÷1.4). Therefore, soccer players can use the T-Car derived parameters as a noninvasive and practical alternative to estimate the specific maximal lactate steady state for soccer.

Rate of utilization of a given fraction of W' (the curvature constant of the power-duration relationship) does not affect fatigue during severe-intensity exercise.

NEW FINDINGS: What is the central question of this study? Does the rate of utilization of W' (the curvature constant of the power-duration relationship) affect fatigue during severe-intensity exercise? What is the main finding and its importance? The magnitude of fatigue after two severe-intensity exercises designed to deplete the same fraction of W' (70%) at two different rates of utilization (fast versus slow) was similar after both exercises. Moreover, the magnitude of fatigue was related to critical power (CP), supporting the contention that CP is a key determinant in fatigue development during high-intensity exercise. Thus, the CP model is a suitable approach to investigate fatigue mechanisms during high-intensity exercise. The depletion of W' (the curvature constant of the power-duration relationship) seems to contribute to fatigue during severe-intensity exercise. Therefore, the aim of this study was to determine the effect of a fast versus a slow rate of utilization of W' on the occurrence of fatigue within the severe-intensity domain. Fifteen healthy male subjects performed tests to determine the critical power, W' and peak torque in the control condition (TCON ) and immediately after two fatiguing work rates (THREE and TEN) set to deplete 70% W' in either 3 (TTHREE ) or 10 min (TTEN ). The TTHREE and TTEN were significantly reduced (F = 19.68, P = 0.01) in comparison to TCON . However, the magnitude of reduction in peak torque (TTHREE  = -19.8 ± 10.1% versus TTEN  = -16.8 ± 13.3%) was the same in the two fatiguing exercises (t = -0.76, P = 0.46). There was a significant inverse relationship between the critical power and the reduction in peak torque during both THREE (r = -0.49, P = 0.03) and TEN (r = -0.62, P = 0.02). In contrast, the W' was not significantly correlated with the reduction in peak torque during both THREE (r = -0.14, P = 0.33) and TEN (r = -0.30, P = 0.10). Thus, fatigue following severe-intensity exercises performed at different rates of utilization of W' was similar when the same work was done above the critical power (i.e. same amount of W' used).

Incremental Testing Design on Slide Board for Speed Skaters: Comparison Between Two Different Protocols.

Piucco, T, O'Connell, J, Stefanyshyn, D, and de Lucas, RD. Incremental testing design on slide board for speed skaters: comparison between two different protocols. J Strength Cond Res 30(11): 3116-3121, 2016-The aim of this study was to investigate the effect of stage duration (Long-stage-LS: 3-minute, Short-stage-SS: 1-minute) on maximal and submaximal aerobic physiological variables during a simulated skating test performed on a slide board. Ten well-trained male speed skaters performed 2 maximal incremental tests on slide board until voluntary exhaustion. The second ventilatory threshold (VT2) was determined by the ventilatory equivalent method. All participants reached the criteria for maximal oxygen uptake (V[Combining Dot Above]O2max) attainment in both protocols. Maximal cadence (CADmax), V[Combining Dot Above]O2 at VT2 and cadence at VT2 (CADVT2) were significantly higher during SS protocol, but maximal heart rate was significantly lower for the SS protocol. V[Combining Dot Above]O2max was significantly correlated with CADmax for the SS (r = 0.62) and LS protocols (r = 0.61). Strong correlations were found between CADmax and CADVT2 during the SS (r = 0.83) and LS protocols (r = 0.76). The results of the present study suggest that either SS or LS slide board incremental protocol can be used to evaluate skaters, since they elicited maximal physiological responses. Additionally, slide board incremental skating tests may be considered as a more specific and practical alternative than laboratory-based tests, especially when a large number of athletes need to be assessed.

The effect of prior exercise intensity on oxygen uptake kinetics during high-intensity running exercise in trained subjects.

PURPOSE: The aim of this study was to compare the effects of two different kinds of prior exercise protocols [continuous exercise (CE) versus intermittent repeated sprint (IRS)] on oxygen uptake (VO2) kinetics parameters during high-intensity running. METHODS: Thirteen male amateur futsal players (age 22.8 ± 6.1 years; mass 76.0 ± 10.2 kg; height 178.7 ± 6.6 cm; VO2max 58.1 ± 4.5 mL kg(-1) min(-1)) performed a maximal incremental running test for the determination of the gas exchange threshold (GET) and maximal VO2 (VO2max). On two different days, the subjects completed a 6-min bout of high-intensity running (50 % ∆) on a treadmill that was 6-min after (1) an identical bout of high-intensity exercise (from control to CE), and (2) a protocol of IRS (6 × 40 m). RESULT: We found significant differences between CE and IRS for the blood lactate concentration ([La]; 6.1 versus 10.7 mmol L(-1), respectively), VO2 baseline (0.74 versus 0.93 L min(-1), respectively) and the heart rate (HR; 102 versus 124 bpm, respectively) before the onset of high-intensity exercise. However, both prior CE and prior IRS significantly increased the absolute primary VO2 amplitude (3.77 and 3.79 L min(-1), respectively, versus control 3.54 L min(-1)), reduced the amplitude of the VO2 slow component (0.26 and 0.21 L min(-1), respectively, versus control 0.50 L min(-1)), and decreased the mean response time (MRT; 28.9 and 28.0 s, respectively, versus control 36.9 s) during subsequent bouts. CONCLUSION: This study showed that different protocols and intensities of prior exercise trigger similar effects on VO2 kinetics during high-intensity running.

Increased platelet oxidative metabolism, blood oxidative stress and neopterin levels after ultra-endurance exercise.

The purpose of the present investigation was to identify muscle damage, inflammatory response and oxidative stress blood markers in athletes undertaking the ultra-endurance MultiSport Brazil race. Eleven well-trained male athletes (34.3 ± 3.1 years, 74.0 ± 7.6 kg; 172.2 ± 5.1 cm) participated in the study and performed the race, which consisted of about 90 km of alternating off-road running, mountain biking and kayaking. Twelve hours before and up to 15 minutes after the race a 10 mL blood sample was drawn in order to measure the following parameters: lactate dehydrogenase and creatine kinase activities, lipid peroxidation, catalase activity, protein carbonylation, respiratory chain complexes I, II and IV activities, oxygen consumption and neopterin concentrations. After the race, plasma lactate dehydrogenase and creatine kinase activities were significantly increased. Erythrocyte TBA-RS levels and plasma protein carbonylation were markedly augmented in post-race samples. Additionally, mitochondrial complex II activity and oxygen consumption in post-race platelet-rich plasma were also increased. These altered biochemical parameters were accompanied by increased plasma neopterin levels. The ultra-endurance event provoked systemic inflammation (increased neopterin) accompanied by marked oxidative stress, likely by increasing oxidative metabolism (increased oxidative mitochondrial function). This might be advantageous during prolonged exercise, mainly for efficient substrate oxidation at the mitochondrial level, even when tissue damage is induced.

The Effects of a Supramaximal Intermittent Training Program on Aerobic and Anaerobic Running Measures in Junior Male Soccer Players.

This study investigated the effectiveness of supplementing regular preseason soccer training with a supramaximal intermittent shuttle-run training (ISRT) model prescribed from Carminatti's Test peak speed (PST-CAR) in aerobic performance-related indices and sprinting speed in male junior soccer players. Twenty-three national-level soccer players (mean ± SD; age 18.07 ± 0.9 y, body height 1.76 ± 0.65 m, body mass 71.9 ± 8.7 kg) were assigned to either an experimental group (EG; n = 13) performing ISRT + soccer training or a control group (CG; n = 10) that followed regular preseason soccer training alone. The following tests were applied before and after the eight-week training intervention: (i) incremental treadmill tests (VO2max and lactate minimum speed - LMS); (ii) linear 30-m sprint test and Carminatti's Test (PST-CAR). Results indicated larger gains for the EG in LMS (Δ = 9.53% vs. 2.82%) and PST-CAR (Δ = 5.50% vs. 2.10%) than in the CG. Furthermore, changes in VO2max produced higher effect size (d) values for the EG (Δ = 6.67%; d = 0.59) than the CG (Δ = 1.88%; d = 0.18). Both groups improved (p = 0.002) their flying 20-m sprint speed (EG: Δ = 1.01%; CG: Δ = 1.56%). However, small decreases were observed for 10-m sprint speed in the CG (Δ = -2.19%; d = -0.44), while only trivial changes were noticed for the EG (Δ = -0.50%; d = -0.16). Our data support that additional supramaximal ISRT is an effective training stimulus to enhance aerobic performance-related indices and promote small improvements in maximal running speed without impairing the soccer players' acceleration capacity. This study also shows that PST-CAR can be useful for individualizing running intensity in supramaximal ISRT modes.

Is the 5-Minute Time-Trial Cycling Test a Valid Predictor of Maximal Oxygen Uptake? An External Cross-Validation Study.

PURPOSE: This study aimed to cross-validate a recently proposed equation for the prediction of maximal oxygen uptake (V˙O2max) in cycling exercise by using the average power output normalized by the body mass from a 5-minute time trial (RPO5-min) as the independent variable. Further, the study aimed to update the predictive equation using Bayesian informative prior distributions and meta-analysis. METHODS: On different days, 49 male cyclists performed an incremental graded exercise test until exhaustion and a 5-minute time trial on a stationary cycle ergometer. We compared the actual V˙O2max with the predicted value obtained from the RPO5-min, using a modified Bayesian Bland-Altman agreement analysis. In addition, this study updated the data on the linear regression between V˙O2max and RPO5-min, by incorporating information from a previous study as a Bayesian informative prior distribution or via meta-analysis. RESULTS: On average, the predicted V˙O2max using RPO5-min underestimated the actual V˙O2max by -6.6 mL·kg-1·min-1 (95% credible interval, -8.6 to -4.7 mL·kg-1·min-1). The lower and upper 95% limits of agreement were -17.2 (-22.7 to -12.3) and 3.8 (-1.0 to 9.5) mL·kg-1·min-1, respectively. When the current study's data were analyzed using the previously published data as a Bayesian informative prior distribution, the accuracy of predicting sample means was found to be better when compared with the data combined via meta-analyses. CONCLUSIONS: The proposed equation presented systematic bias in our sample, in which the prediction underestimated the actual V˙O2max. We provide an updated equation using the previous one as the prior distribution, which could be generalized to a greater audience of cyclists.

Match-Play Running Performance in Professional Male Soccer Players: The Role of Anaerobic Speed Reserve.

Purpose: This study aimed to compare match-play running performance between players with a high (HASR) and low (LASR) anaerobic speed reserve (ASR) profile in professional soccer players. Method: Thirty-six male players from the same club (age: 23.3 ± 5.4 years) took part in this study. Match data were collected from 43 home matches of the first and second division of the Brazilian National Championship over two consecutive seasons. Players had their maximal sprinting (MSS) and aerobic speeds (MAS) determined during field test-based assessments. ASR was defined as MSS minus MAS. Total distance (TD), sprinting distance, number of accelerations and decelerations, absolute peak (PMS(abs)) and mean match sprint speed (MMSS(abs)) and its relative values expressed as a percentage of MSS (PMS(rel) and MMSS(rel)), distance covered > 100% MAS(abs) and > 50% MSS(abs) were compared between the groups and halves. Results: HASR presented greater sprint demand (d > 0.80), PMS(abs) (d = 1.57), and MMSS(abs) (d = 0.99) than the LASR group. The opposite was observed for PMS(rel) and MMSS(rel). The TD and amount of high-intensity accelerations and decelerations were moderately (0.77MAS(abs) and > 50% MSS(abs) decreased between halves (d = 0.72 and 0.77), while the HASR did not (d < 0.10). Conclusion: Our findings indicated that players with larger ASR had greater sprint demand, with a lower relative running intensity, and covered longer distances above MAS. The amplitude of ASR also affected the player's running ability between halves.

Reliability and Validity of Cycling Sprint Performance at Isolinear Mode Without Torque Factor: A Preliminary Study in Well-Trained Male Cyclists.

Purpose: This study aimed to compare the performance-derived parameters utilizing isolinear (ISOLIN) and isovelocity (ISOVEL) sprint cycling modes. Method: For that, 20 male trained cyclists performed 2 sprints of 7 s on an electromagnetically braked cycle ergometer in ISOLIN and six sprints in ISOVEL mode with cadences between 90 and 180 rpm, each separated by 3-min. A linear function modeled the sprints within each mode to extrapolate maximal cadence (CMAX) and torque (TMAX), and a quadratic function was used to extrapolate the apex defined as optimal cadence power (OPTCAD) and peak power output (PMAX). Fifteen subjects performed another 4 sprints at ISOLIN mode on different days to verify the reliability. Results: The measures from the power-cadence relationship were not different between the ISOLIN and ISOVEL modes. Although significant differences were detected in the T-C relationship, TMAX was greater at ISOLIN than ISOVEL (p = .006). On the other hand, CMAX was higher at ISOVEL than ISOLIN (p < .001). The correlation between parameters was large to very large (r = 0.51 to 0.89). However, high limits of agreement were verified. The ISOLIN presented consistency during the trials, and the random errors were acceptable (CV = 5.3% to 11.5%). Conclusion: Using the power-cadence relationship, PMAX and OPTCAD could be detected similarly between the two sprint modes (ISOLIN and ISOVEL). Thus, the findings demonstrated that a single ISOLIN sprint test could be a suitable tool for quantifying the time course of muscle fatigue during and after cycling exercises in well-trained male cyclists.

Muscle Oxidative Capacity in Vivo Is Associated With Physiological Parameters in Trained Rowers.

Purpose: The muscle oxygen uptake (mV˙O2) kinetics following exercise, measured by near-infrared spectroscopy, has been used as a functional evaluation of muscle oxidative metabolism. This study aimed to determine the mV˙O2 off-kinetics and verify the relationship of the recovery rate of mV˙O2 (k) with time-trial performance and different aerobic parameters in trained rowers. Methods: Eleven male rowers (age: 20 ± 3 years; V˙O2max: 4.28 ± 0.35 L·min-1) used a rowing ergometer to perform (I) an incremental test to determine the maximal oxygen uptake (V˙O2max) and peak power output (Ppeak); (II) several visits to determine maximal lactate steady state (MLSS); and (III) a 2000-m rowing ergometer performance test. Also, one test to determine mV˙O2 off-kinetics of the vastus lateralis muscle using a repeated arterial occlusions protocol. Results: The mV˙O2 generated a good monoexponential fit (R2 = 0.960 ± 0.030; SEE = 0.041 ± 0.018%.s-1). The k of mV˙O2 (2.06 ± 0.58 min-1) was associated with relative V˙O2max (r = 0.79), power output at MLSS (r = 0.76), and Ppeak (r = 0.83); however, it was not related with 2000-m rowing performance (r = -0.38 to 0.52; p > .152). Conclusion: These findings suggest that although not associated with rowing performance, the mV˙O2 off-kinetics determined after a submaximal isometric knee extension may be a practical and less-exhaustive approach than invasive responses and incremental tests to assess the muscle oxidative metabolism during a training program.

1) The present study showed that the NIRS-derived mV˙O2 off-kinetics from the vastus lateralis can be used as a functional tool of skeletal muscle oxidative metabolism in rowers.2) The results demonstrated that the recovery rate of mV˙O2 was well correlated with important aerobic parameters such as V˙O2max, maximal lactate steady state, and peak power output during an incremental test.