Competition Between Desired Competitive Result, Tolerable Homeostatic Disturbance, and Psychophysiological Interpretation Determines Pacing Strategy.

Scientific interest in pacing goes back >100 years. Contemporary interest, both as a feature of athletic competition and as a window into understanding fatigue, goes back >30 years. Pacing represents the pattern of energy use designed to produce a competitive result while managing fatigue of different origins. Pacing has been studied both against the clock and during head-to-head competition. Several models have been used to explain pacing, including the teleoanticipation model, the central governor model, the anticipatory-feedback-rating of perceived exertion model, the concept of a learned template, the affordance concept, the integrative governor theory, and as an explanation for "falling behind." Early studies, mostly using time-trial exercise, focused on the need to manage homeostatic disturbance. More recent studies, based on head-to-head competition, have focused on an improved understanding of how psychophysiology, beyond the gestalt concept of rating of perceived exertion, can be understood as a mediator of pacing and as an explanation for falling behind. More recent approaches to pacing have focused on the elements of decision making during sport and have expanded the role of psychophysiological responses including sensory-discriminatory, affective-motivational, and cognitive-evaluative dimensions. These approaches have expanded the understanding of variations in pacing, particularly during head-to-head competition.

The performance during four stationary knife attacks: Implications for tactical training.

With over 72,000 offenses between 2010 and 2020 in the USA, knives were the third most commonly used weapon in all violent crimes between behind personal weapons and handguns. PURPOSE: Examine the performance of different stab (Thrust and overhead) and slash (Figure 8 and Reverse) knife motions to determine how long it takes to execute each motion. In addition, examine the variability in executing each motion to inform future self-defense strategies. METHODS: Twenty subjects (Females, n = 4; Males, n = 16; Height: 179.96 ± 8.66 cm; Weight: 94.99 ± 22.37 kg; Age: 36.95 ± 10.63 years) who were all active-duty law enforcement officers (LEOs) with 13.52 ± 11.23 years of LEO experience were recruited to participate in the study. Each subject completed two trials of the knife motions while wearing wearable motion sensors (ADPM) and recorded with a high-speed camera (GoPro) while using a training knife (Cold Steel). RESULTS: The time to complete the motions were: Thrust, 0.61 ± 0.15 s; Overhead, 0.68 ± 0.14 s; Figure 8, 1.07 ± 0.21 s; and Reverse, 0.62 ± 0.11 s. The Figure 8 motion was significantly slower than the other three motions: F (3, 57) = 101.19, p < 0.001, ηp2 = 0.84. The reliability analysis reported trivial variability and a high level of agreement: Thrust, ICCα = 0.701, SEM = 0.09 s, CV% = 15.02; Overhead, ICCα = 0.878, SEM = 0.05 s, CV% = 6.93; Figure 8, ICCα = 0.906, SEM = 0.07 s, CV% = 6.25, Reverse, ICCα = 0.420, SEM = 0.10 s, CV% = 17.31. DISCUSSION: Most LEOs or civilians within striking distance of someone with a knife may not be able to avoid contact from the knife attacks based on the speed knife attacks could occur. CONCLUSION: The reference data provides pertinent information to update evidence-based training approaches to knife attack preparation and defense.

Optimization of the Critical Speed Concept for Tactical Professionals: A Brief Review.

Tactical professionals often depend on their physical ability and fitness to perform and complete occupational tasks to successfully provide public services or survive on the battlefield. Critical speed (CS), or maximal aerobic steady-state, is a purported measure that predicts performance, prescribes exercise, and detects training adaptions with application to tactical professionals. The CS concept has the versatility to adapt to training with load carriage as an integrated bioenergetic system approach for assessment. The aims of this review are to: (1) provide an overview of tactical populations and the CS concept; (2) describe the different methods and equipment used in CS testing; (3) review the literature on CS associated with tactical occupational tasks; and (4) demonstrate the use of CS-derived exercise prescriptions for tactical populations.

Predictors of Work Efficiency in Structural Firefighters.

OBJECTIVE: Develop a novel work efficiency (WE) metric to quantify firefighter physical ability and identify correlates of WE. METHODS: Physical fitness and anthropometric measurements were taken on 19 male firefighters. Firefighters performed a timed maximal effort simulated fireground test (SFGT). WE was quantified as: (1/[Air depletion × SFGT completion time]) × 10,000. Regression analyses were used to identify predictors of WE. RESULTS: WE was significantly correlated to age, relative body fat, fat mass, occupational experience, jump height, inverted row repetitions, relative bench press and squat strength, treadmill time to exhaustion, relative ventilatory threshold, and relative peak oxygen consumption. Treadmill time to exhaustion and relative lower body strength accounted for the greatest variance in WE (R2 = 0.72, root mean square error = 0.07). CONCLUSION: Aerobic endurance and relative lower body strength were related to an occupationally-specific assessment of firefighter physical ability.

Increased velocity at VO2max and load carriage performance in army ROTC cadets: prescription using the critical velocity concept.

The purpose of this study was to evaluate the effects of using the critical velocity (CV) concept to prescribe two separate high-intensity interval training (HIT) exercise programs aimed at enhancing CV and load carriage performance. 20 young adult participants (male = 15, female = 5) underwent a 4-week training period where they exercised 2 d wk-1. Participants were randomly assigned into two groups: (1) HIT or (2) Load Carriage-HIT (LCHIT). Pre- and post-training assessments included running 3-minute All-Out Test (3MT) to determine critical velocity (CV) and distance prime (D') and two load carriage tasks (400 and 3200 m). There were significant increases in CV (p = 0.005) and velocity at V˙ O2max (vV˙ O2max) (p = 0.037) among the sample but not between training groups. Improvements were observed in 3200 m load carriage performance time (p < 0.001) with a 9.8 and 5.4% decrease in the LCHIT and HIT groups, respectively. Practitioner summary: Critical velocity has shown efficacy as a marker for performance in tactical populations. With the addition of load carriage, there is a reduction in the individual's CV. The CV-concept-prescribed exercises (HIT and LCHIT) 2 days per week for 4 weeks showed improvements in CV, vV˙ O2max and load carriage performance. The use of the CV concept provides a method to prescribe HIT to increase running and load carriage performances in tactical populations.

Predicting Maximal Oxygen Uptake Using the 3-Minute All-Out Test in High-Intensity Functional Training Athletes.

Maximal oxygen uptake (VO2max) and critical speed (CS) are key fatigue-related measurements that demonstrate a relationship to one another and are indicative of athletic endurance performance. This is especially true for those that participate in competitive fitness events. However, the accessibility to a metabolic analyzer to accurately measure VO2max is expensive and time intensive, whereas CS may be measured in the field using a 3 min all-out test (3MT). Therefore, the purpose of this study was to examine the relationship between VO2max and CS in high-intensity functional training (HIFT) athletes. Twenty-five male and female (age: 27.6 ± 4.5 years; height: 174.5 ± 18.3 cm; weight: 77.4 ± 14.8 kg; body fat: 15.7 ± 6.5%) HIFT athletes performed a 3MT as well as a graded exercise test with 48 h between measurements. True VO2max was determined using a square-wave supramaximal verification phase and CS was measured as the average speed of the last 30 s of the 3MT. A statistically significant and positive correlation was observed between relative VO2max and CS values (r = 0.819, p < 0.001). Based on the significant correlation, a linear regression analysis was completed, including sex, in order to develop a VO2max prediction equation (VO2max (mL/kg/min) = 8.449(CS) + 4.387(F = 0, M = 1) + 14.683; standard error of the estimate = 3.34 mL/kg/min). Observed (47.71 ± 6.54 mL/kg/min) and predicted (47.71 ± 5.7 mL/kg/min) VO2max values were compared using a dependent t-test and no significant difference was displayed between the observed and predicted values (p = 1.000). The typical error, coefficient of variation, and intraclass correlation coefficient were 2.26 mL/kg/min, 4.90%, and 0.864, respectively. The positive and significant relationship between VO2max and CS suggests that the 3MT may be a practical alternative to predicting maximal oxygen uptake when time and access to a metabolic analyzer is limited.

Investigation of Variables Associated with Surgical Site Infection following the Management of Canine Cranial Cruciate Ligament Rupture with a Lateral Fabellotibial Suture.

OBJECTIVE: This study investigated variables associated with surgical site infection (SSI) in dogs with cranial cruciate ligament rupture managed with stifle joint examination and lateral fabellotibial suture stabilization. STUDY DESIGN: A retrospective study of dogs that had stifle arthroscopy, stifle arthrotomy, or a combination of both, followed by lateral fabellotibial suture stabilization for cranial cruciate ligament rupture. All cases had a minimum follow-up of 90 days. Lameness grades were recorded preoperatively, and at 6-week and final follow-up. RESULTS: One hundred fifty procedures in 130 dogs met the inclusion criteria. Overall, SSI rate was 17.3% and removal of the lateral fabellotibial suture was performed in 53% of SSI. Multivariable analysis showed significant association between SSI and bodyweight (p = 0.013), and induction using propofol (p = 0.029). Multilevel ordinal logistic regression analysis showed a greater proportion of dogs had a higher lameness grade at 6-week (p = 0.021) and final follow-up (p = 0.002) assessments in the infected compared with non-infected dogs. CONCLUSION: Our study demonstrated a higher SSI incidence than previously reported in dogs undergoing a lateral fabellotibial suture for cranial cruciate ligament rupture. Bodyweight and induction with propofol were identified as significant risk factors for postoperative SSI. Owners could be advised of an increased SSI risk in larger dogs and consideration should be given to selection of induction agent. Dogs that develop an SSI have a worse lameness grade at 6-week and final follow-up.

An Examination and Critique of Current Methods to Determine Exercise Intensity.

Prescribing the frequency, duration, or volume of training is simple as these factors can be altered by manipulating the number of exercise sessions per week, the duration of each session, or the total work performed in a given time frame (e.g., per week). However, prescribing exercise intensity is complex and controversy exists regarding the reliability and validity of the methods used to determine and prescribe intensity. This controversy arises from the absence of an agreed framework for assessing the construct validity of different methods used to determine exercise intensity. In this review, we have evaluated the construct validity of different methods for prescribing exercise intensity based on their ability to provoke homeostatic disturbances (e.g., changes in oxygen uptake kinetics and blood lactate) consistent with the moderate, heavy, and severe domains of exercise. Methods for prescribing exercise intensity include a percentage of anchor measurements, such as maximal oxygen uptake ([Formula: see text]), peak oxygen uptake ([Formula: see text]), maximum heart rate (HRmax), and maximum work rate (i.e., power or velocity-[Formula: see text] or [Formula: see text], respectively), derived from a graded exercise test (GXT). However, despite their common use, it is apparent that prescribing exercise intensity based on a fixed percentage of these maximal anchors has little merit for eliciting distinct or domain-specific homeostatic perturbations. Some have advocated using submaximal anchors, including the ventilatory threshold (VT), the gas exchange threshold (GET), the respiratory compensation point (RCP), the first and second lactate threshold (LT1 and LT2), the maximal lactate steady state (MLSS), critical power (CP), and critical speed (CS). There is some evidence to support the validity of LT1, GET, and VT to delineate the moderate and heavy domains of exercise. However, there is little evidence to support the validity of most commonly used methods, with exception of CP and CS, to delineate the heavy and severe domains of exercise. As acute responses to exercise are not always predictive of chronic adaptations, training studies are required to verify whether different methods to prescribe exercise will affect adaptations to training. Better ways to prescribe exercise intensity should help sport scientists, researchers, clinicians, and coaches to design more effective training programs to achieve greater improvements in health and athletic performance.

Health and wellness coaching positively impacts individuals with chronic pain and pain-related interference.

OBJECTIVES: Health and wellness coaching (HWC) interventions have been reported to improve health outcomes for individuals with chronic diseases such as diabetes, cardiovascular disease, or cancer. However, HWC also holds potential as an effective intervention within a biopsychosocial chronic pain management framework. The aim of the present study was to evaluate the effects of HWC on individuals with chronic pain. METHODS: Participants were referred by their primary care provider or insurance company to a comprehensive telephonic 12-month pain management HWC program. Relationships between pain outcomes and physical and psychological factors were retrospectively analyzed. Mixed linear-effects modeling explored whether physical and psychological variables were associated with pain outcomes over time. RESULTS: Four hundred nineteen participants (female, 58.9%; mean age, 54.8) enrolled in the program and 181 completed the intervention. After 12 months in the program, statistically and clinically significant reductions were observed for pain intensity (Hedges' g = 1.00) and pain-related interference (Hedges' g = 1.13). Linear mixed-effects modeling indicated that improvements in physical functioning and psychological factors were associated with improvements in pain intensity. DISCUSSION: Our results provide a novel analysis on the effects of HWC on chronic pain and pain-related interference. HWC appears to be a promising intervention to improve pain-related outcomes in a population with chronic pain. Further investigation of HWC as an intervention for chronic pain is warranted.

Physiological Performance Measures as Indicators of CrossFit® Performance.

CrossFit® began as another exercise program to improve physical fitness and has rapidly grown into the "sport of fitness". However, little is understood as to the physiological indicators that determine CrossFit® sport performance. The purpose of this study was to determine which physiological performance measure was the greatest indicator of CrossFit® workout performance. Male (n = 12) and female (n = 5) participants successfully completed a treadmill graded exercise test to measure maximal oxygen uptake (VO2max), a 3-minute all-out running test (3MT) to determine critical speed (CS) and the finite capacity for running speeds above CS (D'), a Wingate anaerobic test (WAnT) to assess anaerobic peak and mean power, the CrossFit® total to measure total body strength, as well as the CrossFit® benchmark workouts: Fran, Grace, and Nancy. It was hypothesized that CS and total body strength would be the greatest indicators of CrossFit® performance. Pearson's r correlations were used to determine the relationship of benchmark performance data and the physiological performance measures. For each benchmark-dependent variable, a stepwise linear regression was created using significant correlative data. For the workout Fran, back squat strength explained 42% of the variance. VO2max explained 68% of the variance for the workout Nancy. Lastly, anaerobic peak power explained 57% of the variance for performance on the CrossFit® total. In conclusion, results demonstrated select physiological performance variables may be used to predict CrossFit® workout performance.

Bi-exponential modeling derives novel parameters for the critical speed concept.

All-out exercise testing (AOT) has emerged as a method for quantifying critical speed (CS) and the curvature constant (D'). The AOT method was recently validated for shuttle running yet how that method compares with linear running is unknown. In the present study, we utilized a novel bi-exponential model that derives CS and D' with additional new parameters from the AOT method. Fourteen male athletes (age = 21.6 ± 2.2 years; height = 177 ± 70 cm; weight = 83.0 ± 11.8 kg) completed a graded exercise test (GXT) to derive maximum oxygen uptake ( V˙O2max ) and the average speed between gas exchange threshold and V˙O2max (sΔ50%), a linear AOT, and two shuttle AOTs. Measurement agreement was determined using intraclass correlation coefficient (ICC α ), typical error (TE), and coefficient of variation (CV). The y-asymptote ( S0 ) of the speed-time curve (3.52 ± 0.66 m·sec-1 ) did not differ from sΔ50% (3.49 ± 0.41 m·sec-1 ) or CS (3.77 ± 0.56 m·sec-1 ) (P = 0.34). Strong agreement was observed for estimates of CS (ICC α  = 0.92, TE = 0.18 m·sec-1 , and CV = 5.7%) and D' (ICC α  = 0.94, TE = 16.0 m, CV = 7.6%) with significant (P < 0.01) correlations observed between V˙O2max and CS and between S0 and V˙O2max (r values of 0.74 and 0.84, respectively). The time constant of the decay in speed ( τd ) and the amplitude between maximal speed and S0 ( Ad ) emerged as unique metrics. The Ad and τd metrics may glean new insights for prescribing and interpreting high-intensity exercise using the AOT method.

Value of Wellness Ratings and Countermovement Jumping Velocity to Monitor Performance.

This study examined the relationship between subjective ratings of overall wellness and neuromuscular performance throughout a 6-week intensive offseason strength and conditioning program. Thirty experienced NCAA Division II baseball players completed all phases of the program. A comprehensive wellness rating and 5 countermovement jumps (CMJ5) were measured and averaged for 4 phases of training. Pre- and post-testing measures of strength and speed also were evaluated. Internal consistency of the wellness rating for each phase ranged α = 0.77-0.92, and CMJ5 velocities had decent consistency (ICCα = 0.88, TE = 0.19 m·s-1, CV = 5.90%). The training program evoked significant (p < 0.01) improvements in front squats (d = 0.55), trap bar deadlifts (d = 0.62), chin ups (d = 0.39), 30-yd dash (d = 0.39), with no change in the 300-yd dash (p > 0.05), where d is the treatment effect size. Average CMJ5 velocities (m·s-1) were similar for the preparation phase (1.90 ± 0.25), eccentric phase (1.91 ± 0.28), strength & power phase (1.91 ± 0.24), and recovery phase (1.91 ± 0.30; F = 0.04, p = 0.99, η p 2 = 0.001). No significant correlations were observed for pre-or post-testing measures of wellness ratings in comparison to any performance measures, including a composite standardized score from each performance test at pre-testing (r = 0.22, p = 0.26). The CMJ5 exhibited too high of a typical error to determine a change in neuromuscular status. Additionally, the wellness rating did not reflect changes in relation to performance.

Dynamics of pleasure-displeasure at the limit of exercise tolerance: conceptualizing the sense of exertional physical fatigue as an affective response.

The search for variables involved in the regulation and termination of exercise performance has led to integrative models that attribute a central role to the brain and utilize an array of psychological terms (e.g. sensation, perception, discomfort, tolerance). We propose that theorizing about exercise regulation would benefit from establishing cross-disciplinary bridges to research fields, such as affective psychology and neuroscience, in which changes along the dimension of pleasure-displeasure are considered the main channel via which homeostatic perturbations enter consciousness and dictate corrective action (slowing down or stopping). We hypothesized that ratings of pleasure-displeasure would respond to the severity of homeostatic perturbation and would be related to time to exhaustion during exercise performed at an unsustainable intensity. In a within-subjects experiment (N=15, 13 men and 2 women, age 23.4±2.2 years; maximal oxygen uptake 46.0±8.0 ml kg-1 min-1), we compared the slope of ratings of pleasure-displeasure (acquired every 1 min) during cycling exercise at a power output 10% above critical power until volitional termination under glycogen-loaded and glycogen-depleted conditions. As hypothesized, ratings of pleasure-displeasure declined more steeply under glycogen depletion (P=0.009, d=0.70) and correlated closely with time to exhaustion under both glycogen-loaded (r=0.85; P<0.001) and glycogen-depleted conditions (r=0.83; P<0.001). We conclude that in exercise, as in other domains, changes in pleasure-displeasure may be the main channel via which homeostatic perturbations enter consciousness. This proposal may have important implications for conceptualizing and identifying the neurobiological mechanisms of the sense of exertional physical fatigue.

Energetics of male field-sport athletes during the 3-min all-out test for linear and shuttle-based running.

PURPOSE: All-out, non-steady state running makes for difficult comparisons regarding linear and shuttle running; yet such differences remain an important distinction for field-based sports. The purpose of the study was to determine whether an energetic approach could be used to differentiate all-out linear from shuttle running. METHODS: Fifteen male field-sport athletes volunteered for the study (means ± SD): age, 21.53 ± 2.23 years; height, 1.78 ± 0.68 m; weight, 83.85 ± 11.73 kg. Athletes completed a graded exercise test, a 3-min linear all-out test and two all-out shuttle tests of varied distances (25 m and 50 m shuttles). RESULTS: Significant differences between the all-out tests were found for critical speed (CS) [F(8.97), p < 0.001), D' (finite capacity for running speeds exceeding critical speed) [F(7.83), p = 0.001], total distance covered [F(85.31), p < 0.001], peak energetic cost ([Formula: see text]) [F(45.60), p < 0.001], peak metabolic power ([Formula: see text]) [F(23.36), p < 0.001], average [Formula: see text] [F(548.74), p < 0.001], maximal speed [F(22.87), p < 0.001] and fatigue index [F(3.93), p = 0.027]. Non-significant differences were evident for average [Formula: see text] [F(2.47), p = 0.097], total [Formula: see text] [F(0.86), p = 0.416] and total [Formula: see text] [F(2.11), p = 0.134]. CONCLUSIONS: The energetic approach provides insights into performance characteristics that differentiate linear from shuttle running, yet surprising similarities between tests were evident. Key parameters from all-out linear and shuttle running appear to be partly interchangeable between tests, indicating that the final choice between linear and shuttle testing should be based on the requirements of the sport.

Validation of the 3-Minute All-Out Exercise Test for Shuttle Running Prescription.

Saari, A, Dicks, ND, Hartman, ME, and Pettitt, RW. Validation of the 3-minute all-out exercise test for shuttle running prescription. J Strength Cond Res 33(6): 1679-1685, 2019-A 3-minute all-out exercise test (3 MT) for running has been developed to determine critical speed (CS) and finite capacity for running speeds > CS (D') which allow for the prediction of time limits (TLIMs) associated with running different distances. Most team sports require shuttle running; however, the 3 MT was validated for uninterrupted, track running and not shuttle running. The purpose of this study was to examine the efficacy of shuttle running 3 MT to determine CS and D'. A total of 12 subjects were tested using a baseline 3 MT along with 3 separate distance time trials of all-out shuttle running to determine true CS and D'. The 3 MT (2.94 ± 0.39 m·s) and the true CS (3.00 ± 0.36 m·s) for shuttle running did not differ (p = 0.71) and had a coefficient of variation (CV) of 7.7%. Conversely, D' from the 3 MT exceeded true D' by 42 m (p = 0.04, CV = 36%). The TLIMs estimated for the 3 different distances were within ∼2-6% (p = 0.60). Based on these outcomes, the shuttle run 3 MT may offer a suitable method for prescribing shuttle running interval training.

Critical Speed as a Measure of Aerobic Fitness for Male Rugby Union Players.

PURPOSE: To compare critical speed (CS) derived from all-out testing (AOT) for linear and shuttle running with metrics from a graded exercise test, the Yo-Yo Intermittent Recovery Test  Level 1 (YYIR1), and estimation of an 800-m-shuttle time trial. METHODS: Twelve male rugby players completed a graded exercise test, the YYIR1, a linear AOT, shuttle AOTs of 25 and 50 m, and an 800-m-shuttle time trial consisting of 32 × 25-m shuttles. RESULTS: Strong linear correlations were observed between maximum oxygen uptake ( V˙O2max ) and CS (m·s-1) derived from the linear AOT (3.68 [0.62], r = .90, P < .01) and 50-m-shuttle AOT (3.19 [0.26], r = .83, P < .01). Conversely, V˙O2max showed lower correlations with speeds evoking CS from 25-m AOT (2.86 [0.18], r = .42, P = .18) and YYIR1 (4.36 [0.11], r = .55, P = .07). The 800-m time trial (213.58 [15.84] s) was best predicted using parameters from the 25-m AOT (r = .93, SEE = 6.60 s, P < .001). CONCLUSIONS: The AOT is a valuable method of assessing performance-specific fitness, with CS from linear and 50-m-shuttle AOTs being strong predictors of V˙O2max , rivaling metrics from the graded exercise test. The YYIR1 offered limited utility compared with the AOT method.

Reliability and validity of the 3-min all-out running test

Abstract Background/Aim Determine critical speed (CS) and running distance above CS (D'), as estimated from the 3-min all-out running test (3MT) is reliable and predictive of CS and D' determined from time trials. Methods Seven males (26 ± 5 years, VO2max: 56.6 ± 4.1 ml·kg-1·min-1) completed an incremental treadmill test, three separate time trials (Tlim) of 800, 1600, and 2400m to determine CS and D', and two 3MTs to estimate CS and D'. Results Estimates of trial 1 (CS =3.90±0.41 m·s-1, D'=176±42 m) and trial 2 (CS=3.89 ± 0.48 m·s-1, D' = 183±35 m) of the 3MT did not differ. Estimates of CS (ICC=0.95, CV=2.97%) and D' (ICC=0.93, CV=5.12%) from the 3MT were reliable. The 3MT trials provided valid estimates of CS as determined using regression of the three time trials (ICCs ranged 0.88-0.93, TE ranged 0.13-0.15 m·s-1, CV ranged 3.32-4.76%). The 3 MT underestimated D' by∼16%, a difference exceeding the test-retest variability. Conclusions Estimates of CS were valid and reliable; however, assessment of D' from the 3MT may not estimate anaerobic capacity accurately.

Resumo Antecedentes/Objetivo Determinar se a velocidade crítica (CS) e a distância acima da CS (D'), estimadaso pelo teste de três minutos máximo (3MT) é confiável e preditiva de CS e D' determinada a partir dos modelos lineares. Métodos Sete homens (26 ± 5 anos, VO2max:56,6 ± 4,1 ml·kg-1·min-1) completaram um teste incremental em esteira, três tomadas de tempo separadamente para 800, 1.600 e 2.400 m, para determinar CS e D' e 2 3MTs para estimar CS e D'. Resultados O primeiro 3 MT (CS = 3,90 ± 0,41 m·s-1, D' = 176 ± 42m) e o segundo 3 MT (CS = 3,89 ± 0,48 m·s-1, D' = 183 ± 35m) não foram diferentes. Estimativas do CS (ICC = 0,95, CV = 2,97%) e D' (ICC = 0,93, CV = 5,12%) a partir de 3 MT eram confiáveis. Os 3 MTs forneceram estimativas válidas de CS (ICC variou de 0,88-0,93, variaram de 0,13 a 0,15 ms TE, CV variou de 3,32 a 4,76%); 3 MT subestimou D' em ∼16%, uma diferença maior de variabilidade teste-reteste. Conclusões Estimativas CS são válidas e confiáveis. No entanto, a avaliação de D' a partir do 3MT não pode estimar com precisão a capacidade anaeróbica.

Antecedentes/Objetivos Determinar si la velocidad crítica (VC) y la distancia por encima de la VC (D'), según la estimación de la prueba de 3 minutos máximos (3MT) es fiable y predictiva de la VC y la D' determinada a partir de los mejores tiempos de carrera personales. Métodos Siete varones (26 ± 5 años, VO2máx: 56,6 ± 4,1 ml·kg-1·min-1) completaron una prueba progresiva en la cinta de correr, con tres períodos de tiempo separados de 800, 1.600 y 2.400 m para determinar la VC y la D' y dos 3MT para estimar la VC y la D'. Resultados Las estimaciones del ensayo 1 (VC = 3,90 ± 0,41 m·s-1, D' = 176 ± 42 m) y del ensayo 2 (VC = 3,89 ± 0,48 m·s-1, D' = 183 ± 35 m) de la prueba 3MT no fueron diferentes. Las estimaciones de la VC (ICC = 0,95; CV = 2,97%) y D' (ICC = 0,93; CV = 5,12%) a partir de la prueba 3MT fueron fiables. Las pruebas 3MT proporcionaron estimaciones válidas de la VC, como se determinó mediante regresión de las tres pruebas de tiempo (ICC se clasificaron desde 0,88 hasta 0,93 y la TE osciló entre 0,13 y 0,15 m.s-1, la CV varió del 3,32 al 4,76%). La D' 3MT subestimó el ∼16%, una diferencia superior a la variabilidad test-retest. Conclusiones Las estimaciones de VC fueron válidas y fiables; Sin embargo, la evaluación de D' desde la prueba de 3MT no puede estimar con precisión la capacidad anaeróbica.

Validity of Critical Velocity Concept for Weighted Sprinting Performance.

We investigated the validity of a recently developed equation for predicting sprinting times of various tactical loads based upon the performance of a running 3-min all-out exercise test (3MT). Thirteen recreationally trained participants completed the running 3MT to determine critical velocity (CV) and finite running capacity for running velocities exceeding CV (D'). Two subsequent counterbalanced loaded sprints of 800 and 1000 m distances with 20 and 15% of their body mass, respectively, were evaluated. Estimated times (t, sec) for running 800 and 1000 m with a tactical load was derived using t = (D - D')/CV. Critical velocity adjusted for an added load using the following regression equation: original CV + (-0.0638 × %load) + 0.6982, D was 800 or 1000 m, and whole percentage load was ~15 or 20% of the participant's body mass. From the 3MT, CV (3.80 ± 0.5 m·s-1) and D' (200 ± 49.88 m) values were determined. The typical error of predicting actual times for the 800 and 1000 m loaded sprints were 5.6 and 10.1 s, with corresponding ICCs of 0.95 and 0.87, and coefficient of variations of 2.9 and 4.3%. The effect size differences between estimated and actual sprint times were small (0.27) and moderate (0.60) for 800 and 1000 m, respectively. The adjustment to CV through the regression equation yields small to moderate overestimates of maximally loaded sprint times for distances of 800 and 1000 m. Whether such errors remain pervasive for prescribing high-intensity interval training is unclear and requires further investigation.