Peak Running Velocity vs. Critical Speed: Which One Is Better to Prescribe Endurance Training to Recreational Runners?

ABSTRACT: Figueiredo, DH, Figueiredo, DH, Manoel, FA, and Machado, FA. Peak running velocity vs. critical speed: which one is better to prescribe endurance training to recreational runners? J Strength Cond Res 37(9): 1783-1788, 2023-This study aimed to evaluate the effects of 5 weeks of training prescribed by peak running velocity obtained on the track (Vpeak_TR) and their respective time limit (Tlim), as well as by critical speed (CS), on physiological and endurance performance parameters in recreational runners. Twenty-two male runners were distributed into a Vpeak_TR group (GVP) and CS group (GCS) with a predefined program, alternating moderate-intensity continuous training and high-intensity interval training. Maximum oxygen uptake (V̇O2max), and its respective velocity (vV̇O2max), Vpeak_TR, Tlim at 100% Vpeak_TR, 5-km running performance, CS, and D' (maximum distance covered above CS) were assessed at pretraining and posttraining period. There was a significant increase from pretraining to posttraining in Vpeak_TR (GVP = 4.5 ± 3.1% vs. GCS = 7.5 ± 4.2%), vV̇O2max (GVP = 3.9 ± 3.8% vs. GCS = 8.6 ± 6.7%), and mean velocity 5-km (GVP = 5.6 ± 3.3% vs. GCS = 7.3 ± 3.5%) and decrease in 5-km time (GVP = -5.1 ± 3.0% vs. GCS = -6.8 ± 3.0%). CS and V̇O2max significantly improved in GCS (9.3 ± 8.4% and 6.0 ± 6.8%, respectively), with no difference for GVP (2.8 ± 5.6% and 1.3 ± 8.4%, respectively). No differences were observed between groups for all variables. These findings give further supports to the notion that both variables obtained on the track are valid tools to prescribed training in recreational runners.

Dose-Response Relationship Between Internal Training Load and Changes in Performance During the Preseason in Youth Soccer Players.

ABSTRACT: Figueiredo, DH, Figueiredo, DH, Moreira, A, Gonçalves, HR, and Dourado, AC. Dose-response relationship between internal training load and changes in performance during the preseason in youth soccer players. J Strength Cond Res 35(8): 2294-2301, 2021-The aim of this study was to describe training intensity distribution based on the session rating of perceived exertion (sRPE) and heart rate (HR) methods and examine the dose-response relation between internal training load (ITL) and change in performance of 16 youth soccer players (mean ± SD age: 18.75 ± 0.68 years, height: 175.3 ± 5.5 cm, body mass: 68.7 ± 6.5 kg, and body fat: 10.7 ± 1.2%) belonging to a Brazilian first division team during a 3-week preseason. The sRPE and HR data were registered daily to calculate the ITL and the training intensity distribution, in 3 intensity zones (low, moderate, and high). The Yo-yo Intermittent Recovery Level 1 (Yo-yo IR1) was evaluated before and after experimental period. The total time spent in the low-intensity zone (HR method) was greater (p < 0.01) compared with the moderate- and high-intensity zones. No difference was observed between training intensity zones determined by the sRPE method (p > 0.05). Negative correlations were observed between weekly mean sRPE-TL (r = -0.69), Edward's-TL (r = -0.50), and change in Yo-yo IR1. Linear regression indicated that weekly mean sRPE-TL (F1;14 = 13.3; p < 0.01) and Edward's-TL (F1;14 = 4.8; p < 0.05) predicted 48.7 and 25.5% of the variance in performance change, respectively. Stepwise linear regression revealed that these 2-predictor variables (F2;13 = 18.9; p < 0.001) explained 74.5% of the variance in performance change. The results suggest that the sRPE and HR methods cannot be used interchangeably to determine training intensity distribution. Moreover, sRPE-TL seems to be more effective than the HR-based TL method to predict changes in performance in youth soccer players.

Características antropométricas e motoras em jogadores de futebol: diferenças entre categorias sub17. sub19 e profissional / Antrophometric and motor caratheristics in soccer players: differences between under 17. under 19 and professional categories

O objetivo do presente estudo foi analisar e comparar as características antropométricas e motoras de atletas pertencentes as categorias Sub17, Sub19 e Profissional. Todos os dados foram coletados anteriormente ao início da temporada competitiva. A amostra deste estudo foi composta por 48 futebolistas masculinos divididos em três grupos: Sub17 (n=16), Sub19 (n=16) e Profissional (n=16). Para avaliar as características antropométricas foram realizadas avaliações de estatura e de composição corporal por meio de Pletismografia por deslocamento de ar. Já para determinação das características motoras foram realizados os testes de resistência aeróbia (Yo-Yo IR1); Counter movement jump (CMJ); Squat jump (SJ); performance de sprint 5m e 30m e potência anaeróbia (RAST teste) para determinação das potências máxima, média e mínima. Para determinar as diferenças entre as categorias no que se refere as características antropométricas e motoras uma ANOVA one way complementando-se com o teste posthoc de Bonferroni foi utilizado, levando-se em consideração um nível de significância de p>0,016. Atletas profissionais apresentaram maiores valores de peso corporal e massa magra absoluta se comparadas as categorias Sub17 e Sub19, não sendo identificadas diferenças para massa gorda absoluta e relativa e massa magra relativa. Não foram identificadas diferenças antropométricas entre os atletas das categorias Sub17 e Sub19. Atletas profissionais apresentaram valores de CMJ, SJ, sprint de 30m e potência máxima, média e mínima maiores do que atletas Sub17 e Sub19, não apresentando diferença em relação ao Yo-Yo IR1 e sprint de 5m. Atletas Sub19 apresentaram maiores valores de Yo-Yo IR1 se comparados ao Sub17 e Profissionais e maiores valores de CMJ, sprint de 30m e potência média e mínima se comparado aos atletas Sub17. Atletas de diferentes categorias apresentam características antropométricas e motoras distintas, enfatizando a importância em acompanhar o desenvolvimento destas características de acordo com a idade....(AU)

The aim of the present study was to analyze and compare the anthropometric and motor characteristics of under 17, under 19 and Professional athletes. All data were collected prior to the beginning of the competitive season. The sample of this study was composed of 48 male soccer players divided into three groups: Under 17 (n=16), Under 19 (n=16) and Professional (n=16). To evaluate anthropometric characteristics, height and body composition were performed by means of air displacement pletismography. For determination of the motor characteristics the aerobic resistance test (Yo-Yo IR1), Counter movement jump (CMJ), Squat jump (SJ), performance of 5m and 30 m sprint and anaerobic power (RAST test) to determine the maximum, mean and minimum power were performed. To determine the differences between the categories regarding anthropometric and motor characteristics, a one-way ANOVA complemented with Bonferroni post-hoc test was used, with a level of significance of p>0,016. Professional athletes shown higher values of body weight and absolute lean mass compared to Under 17 and Under 19 categories, with no difference for absolute and relative fat mass and relative lean mass. No anthropometric differences were identified among athletes in the Under 17 and Under 19 categories. Professional athletes presented values of CMJ, SJ, sprint of 30m and maximal, mean, and minimum power higher than Under 17 and Under 19 athletes, with no difference in relation to Yo-Yo IR1 and sprint of 5m. Under 19 athletes presented higher values of Yo-Yo IR1 compared to Under 17 and Professionals, and higher values of CMJ, sprint of 30 m, mean and, minimum power compared to Under 17 athletes. Athletes of different categories present distinct anthropometric and motor characteristics, emphasizing the importance of accompanying the development of these characteristics according to playing age....(AU)

Effect of Overload and Tapering on Individual Heart Rate Variability, Stress Tolerance, and Intermittent Running Performance in Soccer Players During a Preseason.

Figueiredo, DH, Figueiredo, DH, Moreira, A, Gonçalves, HR, and Stanganelli, LCR. Effect of overload and tapering on individual heart rate variability, stress tolerance, and intermittent running performance in soccer players during a preseason. J Strength Cond Res 33(5): 1222-1231, 2019-This study evaluates the weekly natural log of the root-mean-square difference of successive R-R intervals (lnRMSSDmean), its coefficient of variation (lnRMSSDcv), training load (TL), stress tolerance (ST), and changes in intermittent running performance in response to a 2-week overload (OL) followed by a 1-week taper (TP) during a preseason. Additionally, we determined the relationships between these variables. Ultra-short lnRMSSD, psychometric responses, and ratings of perceived exertion were evaluated daily among 16 under-19 soccer players. At the end of each training phase, the athletes performed the Yo-Yo Intermittent Recovery test level 1 (Yo-Yo). Group analysis showed a decrease in lnRMSSDmean and ST, increases in lnRMSSDcv, and decreases in the Yo-Yo during OL, with a return to baseline levels and a trivial increase in the Yo-Yo during TP. Small to very large correlations were found between lnRMSSDmean and lnRMSSDcv values, with changes in Yo-Yo, TL, monotony, and strain during the preseason (r values ranging from -0.27 to 0.82). No correlation was found between lnRMSSD responses and ST. During OL, athletes with decreases in lnRMSSDmean and increases in lnRMSSDcv accumulated higher perceived TL, with higher monotony and overall stress, and presented a decrease in ST and intermittent running performance, interpreted as a negative adaptation in response to the maintenance of higher TL. During TP, these responses were reversed, leading to an increase in intermittent running performance. In addition, subjective measures of ST may be used to provide early indicators of training adaptation in soccer players.

Time limit at peak speed without prior warm-up: Effects on test duration, heart rate and rating of perceived exertion / Tiempo límite en la velocidad máxima sin calentamiento previo: efectos sobre la duración de la prueba, frecuencia cardíaca y grado de esfuerzo percibido

Background: Time limit (tlim) at peak speed (Vpeak), that is maximal time that an individual can keep running at maximal intensity, is used to prescribe interval durations during interval training. The aim of this study was to compare two protocols (without or with 15 minutes of warm-up) for the tlim determination at 100% of Vpeak in untrained men. Material and method: Twelve untrained young men performed three running tests on a treadmill: one maximal incremental test to determine Vpeak and two rectangular tests, performed in randomized order, without a warm-up (tlim0) or with a 15-minute warm-up duration (tlim15) at 60% of Vpeak to determine the tlim at 100% of Vpeak, after the warm-up the tests were performed at the speed of the individual Vpeak until volitional exhaustion. During the tests, heart rate (HR) and rating of perceived exertion (RPE) were monitored and blood lactate sampling was collected prior to session (LApre); immediately post-exercise (LA0-min); 3 min (LA3-min), 5 min (LA5-min) and 7 min (LA7-min) post-exercise to determine lactate concentrations. The Shapiro-Wilk test was used and confirmed the normality of the data distribution, with maximal and submaximal values compared using Student ́s t test for dependent samples. Results: Test duration at tlim0 was significant higher than that at tlim15 (P = 0.02). Additionally, different tlim protocols influenced HR and RPE submaximal responses and did not modify lactate concentrations or maximal variables (HRmax and RPEmax). Conclusions: These findings suggest that the determination of tlim at 100% of Vpeak without a prior warm-up led to a higher test duration in untrained men

Objetivos: Tiempo límite (tlim) en la velocidad máxima (Vpico), que es el tiempo máximo que un individuo puede permanecer corriendo en la intensidade máxima, se utiliza para prescribir la duración de los intervalos durante el entrenamiento interválico. El objetivo de este estudio fue comparar dos protocolos (sin o con 15 minutos de calentamiento) para la determinación de tlim al 100% de la Vpico en hombres no entrenados. Material y método: Doce jóvenes no entrenados realizaron tres pruebas de carrera en la cinta rodante: una prueba incremental máxima para determinar Vpico y dos pruebas rectangulares, realizadas en orden aleatorio, sin calentamiento (tlim0) o con una duración de calentamiento de 15 minutos (tlim15) al 60% de la Vpico para determinar el tlim al 100% de la Vpico; después del calentamiento las pruebas fueron realizadas en la velocidad de la Vpico individual hasta el agotamiento voluntario. Durante las pruebas, la frecuencia cardíaca (FC) y el grado de esfuerzo percibido (RPE) fueron monitorizadas y se tomaron muestras de sangre antes de la sesión (LApre); inmediatamente después del ejercicio (LA0-min); 3 min (LA3-min), 5 min (LA5-min) y 7 min (LA7-min) después del ejercicio para determinar las concentraciones de lactato. Se utilizó la prueba de Shapiro Wilk y se confirmó la normalidad de la distribución de los datos, con los valores máximos y submáximos comparados utilizando la prueba t de Student para muestras dependientes. Resultados: La duración de la prueba en el tlim0 fue significativamente mayor que aquella en el tlim15 (P = 0.02). Además, los diferentes protocolos de tlim influenciaron las respuestas submáximas de FC y RPE y no modificaron las concentraciones de lactato o las variables máximas (FCmax y RPEmax). Conclusiones: Estos resultados sugieren que la determinación del tlim en la 100% de la Vpico sin calentamiento prévio lleva a una mayor duración de la prueba em hombres no entrenados

Effects of chronic beetroot juice supplementation on maximum oxygen uptake, velocity associated with maximum oxygen uptake, and peak velocity in recreational runners: a double-blinded, randomized and crossover study.

PURPOSE: This study investigated the effects of chronic 3-day beetroot juice (BRJ) supplementation on maximum oxygen uptake (VO2max), velocity associated with VO2max(vVO2max), and peak velocity (Vpeak) in recreational runners. METHODS: Thirteen male recreational runners (age 28.2 ± 3.0 years, height 176.8 ± 0.1 cm, body mass 74.4 ± 9.5 kg) performed four tests on a treadmill in a randomized, double-blind, crossover design: two maximum incremental tests to determine VO2max and vVO2max, and two tests to determine Vpeak. Trials were performed following 3 days of supplementation of NO3--rich BRJ in natura (8.4 mmol NO3- day- 1) or BRJ NO3--depleted placebo (0.01 mmol NO3- day- 1), with the last dose being ingested 2 h before each test. During the tests, maximum heart rate (HRmax), maximal rating of perceived exertion (RPEmax), pre- and post-test glucose concentrations (Glucpre, Glucpost), and peak blood lactate concentration were determined. RESULTS: VO2max was higher following BRJ vs PLA (46.6 ± 6.4 vs 45.1 ± 5.8 mL kg- 1 min- 1; P = 0.022), as well as vVO2max (14.5 ± 0.8 vs 13.9 ± 1.0 km h- 1P = 0.024) and Vpeak (15.5 ± 1.1 vs 15.2 ± 1.2 km h- 1P = 0.038), with no differences in the other variables. CONCLUSION: Consumption of NO3--rich BRJ in natura (8.4 mmol NO3- day- 1) once per day for 3 days improved VO2max, vVO2max and Vpeak in recreational runners without changing the other analyzed variables.