Effects of 4 Different Velocity-Based Resistance-Training Programming Models on Physical Performance.

PURPOSE: To examine the effects of 4 programming models (linear [LP], undulating [UP], reverse [RP], and constant [CP]) on physical performance. METHODS: Forty-eight moderately strength-trained men were randomly assigned to LP, UP, RP, and CP groups according to their 1-repetition maximum (1RM) in the full-squat exercise (SQ) and followed an 8-week training intervention using the SQ and monitoring movement velocity for every repetition. All groups trained with similar mean relative intensity (65% 1RM), number of repetitions (240), sets (3), and interset recovery (4 min) throughout the training program. Pretraining and posttraining measurements included, in the SQ, 1RM load, the average velocity attained for all absolute loads common to pretests and posttests (AV), and the average velocity for loads that were moved faster (AV > 1) and slower (AV < 1) than 1 m·s-1 at pretraining tests. Moreover, countermovement jump height and 20-m running sprint time were measured. RESULTS: A significant time effect was found for all variables analyzed (P < .05), except for 20-m running sprint time. Significant group × time interactions were observed for 1RM, AV > 1, and AV (P < .05). After training, all groups attained significant strength gains on 1RM, AV, AV > 1, and AV < 1 (P < .001-.01). LP and RP groups improved their countermovement jump height (P < .01), but no significant changes were observed for UP and CP. No significant improvements were achieved in 20-m running sprint time for any groups. CONCLUSIONS: These different programming models are all suitable for improving physical performance. LP and RP induce similar or greater gains in physical performance than UP and CP.

Acute Mechanical and Metabolic Responses to Different Resistance Training Protocols With Equated Volume Load.

PURPOSE: To investigate the effect of different resistance training protocols with equated volume load on acute mechanical and metabolic responses. METHODS: In a randomized order, 18 men performed 8 different training protocols in the bench press exercise consisting of (sets, repetitions, intensity, and interset recoveries) 3 × 16, 40% 1-repetition maximum (1RM), 2 and 5 minutes; 6 × 8, 40% 1RM, 2 and 5 minutes; 3 × 8, 80% 1RM, 2 and 5 minutes; and 6 × 4, 80% 1RM, 2 and 5 minutes. Volume load was equalized between protocols (1920 arbitrary units). Velocity loss and effort index were calculated during the session. Movement velocity against the 60% 1RM and blood lactate concentration pre-post exercise were used to assess the mechanical and metabolic responses, respectively. RESULTS: Resistance training protocols performed with heavy load (80% 1RM) resulted in a lower (P < .05) total number of repetitions (effect size = -2.44) and volume load (effect size = -1.79) than the scheduled ones when longer set configurations and shorter rest periods were used in the same protocol (ie, higher-training-density protocols). Protocols including a higher number of repetitions per set and shorter rest times induced higher velocity loss, effort index, and lactate concentrations than the rest of the protocols. CONCLUSIONS: Our results suggest that resistance training protocols with similar volume load but different training variables (ie, intensity, number of sets and repetitions, rest between sets) produce different responses. Implementing a lower number of repetitions per set and longer rest intervals is recommended to reduce the intrasession and postsession fatigue.

Evaluación de la respuesta aguda sobre distintas variables mecánicas, fisiológicas y metabólicas tras un ejercicio de subida de escaleras con equipo específico en bomberos profesionales / Avaliação da resposta aguda em diferentes variáveis mecânicas, fisiológicas e metabólicas após um exercíciode subida de escada com equipamentos específicos em bombeiros profissionais / Evaluation of the acute response on different mechanical, physiological and metabolic variables after a stair- climbing exercise with specific gear in professional firefighters

Objetivo: Analizar las respuestas agudas de una prueba de subida de escaleras con equipo especifico sobre distintas variables mecánicas, metabólicas yfisiológicas en un grupo de bomberos profesionales. Método: 34 bomberos (Edad: 42.7 ± 8.2 años; Peso: 76.16 ± 6.70 kg; Estatura: 177 ± 5 cm) realizaron una prueba de subida de una escalera de seisplantas con equipo específico a la máxima velocidad. Antes y después de dicha prueba, se evaluó su capacidad de salto vertical (CMJ) y la fuerza muscularde las piernas en el ejercicio de sentadilla completa con una carga similar a la carga del equipo específico (35 kg, VMP35kg); se analizaron tambiéndiferentes variables fisiológicas (saturación de oxígeno [O2] y frecuencia cardiaca [FC]) y metabólicas (lactato en sangre [La]). Los participantes seagruparon en 3 rangos de edad (G1: 26-35 años; G2: 36-45 años; G3: ≥ 46 años).Resultados: Se observó una pérdida significativa (p < 0.001) en la capacidad de salto CMJ y en la VMP35kg tras la prueba de subida de escaleras, junto conun aumento significativo (p < 0.001) en [La] y en la FC. Entre grupos de edad, se hallaron diferencias significativas (p < 0.05) en el salto CMJ y en la VMPde la sentadilla con 35 kg en los G1 y G2 con respecto al G3, siempre a favor de los grupos de menos edad.Conclusiones:El ejercicio de subida de escaleras con el equipo específico produjo una disminución significativa del rendimiento en la fuerza muscular delas piernas, así como un aumento significativo en las variables fisiológicas y metabólicas de FC y La, y una disminución significativa en la saturación de O2,indicando que este tipo de esfuerzo produce una fatiga elevada.(AU)

Objective: To analyse the acute response on different mechanical, physiological and metabolic variables after a stair-climbing exercise with specific gearin professional firefighters.Method: 34 professional firefighters (Age: 42.7 ± 8.2 years; Weight: 76.16 ± 6.70 kg; Heigh: 177 ± 5 cm) performed a stair-climbing exercise over 6 floorswith specific gear at maximum speed. Before and after this exercise, different mechanical variables: vertical jump capacity (CMJ) and lower limb strengthin full squat exercise with a load equivalent to that of the specific gear (35 kg, VMP35kg); and physiological and metabolic variables: oxygen saturation[O2], heart rate [FC] and lactate [La] were analysed. Participants were also grouped by age ranges (G1: 26-35 years; G2: 36-45 years; G3: ≥ 46 years).Results: A significant decrease (p < 0.001) in vertical jump capacity and lower limb strength in full squat after the stair-climbing exercise was observed. Inaddition, a significant increase (p < 0.001) in lactate and heart rate was also observed. When analysing by age ranges, significant differences (p < 0.05) invertical jump and squat exercise with 35kg were observed in G1 and G2 with respect to G3, always in favor of the younger age group. Conclusions: The stair-climbing exercise with specific gear showed a significant decrease in lower limb strength performance, as well as a significantincrease in heart rate and lactate variables, and a significant decrease in oxygen saturation. These results indicate that this type of effort induces highlevels of fatigue.(AU)

Objetivo: Analisar as respostas agudas de um teste de subida de escada com equipamento específico sobre diferentes variáveis mecânicas, metabólicas efisiológicas em um grupo de bombeiros profissionais.Método: 34 bombeiros (Idade: 42.7 ± 8.2 anos; Peso: 76.16 ± 6.70 kg; Altura: 177 ± 5 cm) realizaram um teste de subida de escada de seis andares comequipamento específico em velocidade máxima. Antes e após tal teste, foram avaliadas a capacidade de salto vertical (CMJ) e força muscular da perna noexercício de agachamento completo com carga semelhante à carga do equipamento específico (35kg, VMP35kg); Diferentes variáveis fisiológicas(saturação de oxigênio [O2] e frequência cardíaca [FC]) e metabólicas (lactato sanguíneo [La]) também foram analisadas. Os participantes foramagrupados em 3 faixas etárias (G1: 26-35 anos; G2: 36-45 anos; G3: ≥ 46 anos).Resultados: Foi observada uma perda significativa (p < 0,001) na capacidade de salto do CMJ e VMP35kg após o teste de subir escadas, juntamente comum aumento significativo (p < 0,001) na [La] e na FC. Entre as faixas etárias, foram encontradas diferenças significativas (p < 0,05) no salto CMJ e noagachamento VMP de 35kg no G1 e G2 em relação ao G3, sempre a favor das faixas etárias mais jovensConclusões: O exercício de subir escadas com o equipamento específico produziu uma diminuição significativa do desempenho na força muscular daspernas, assim como um aumento significativo nas variáveis fisiológicas e metabólicas de FC e La, e uma diminuição significativa na saturação de O2,indicando que este tipo de esforço produz alta fadiga.(AU)

Specific Adaptations to 0%, 15%, 25%, and 50% Velocity-Loss Thresholds During Bench Press Training.

PURPOSE: To compare the effect of 4 velocity-loss (VL) thresholds-0% (VL0), 15% (VL15), 25% (VL25), and 50% (VL50)-on strength gains, neuromuscular adaptations, and muscle hypertrophy during the bench press (BP) exercise using intensities ranging from 55% to 70% of 1-repetition maximum (1RM). METHODS: Fifty resistance-trained men were randomly assigned to 4 groups that followed an 8-week (16 sessions) BP training program at 55% to 70% 1RM but differed in the VL allowed in each set (VL0, VL15, VL25, and VL50). Assessments performed before (pre) and after (post) the training program included (1) cross-sectional area of pectoralis major muscle, (2) maximal isometric test, (3) progressive loading test, and (4) fatigue test in the BP exercise. RESULTS: A significant group × time interaction was found for 1RM (P = .01), where all groups except VL0 showed significant gains in 1RM strength (P < .001). The VL25 group attained the greatest gains in 1RM strength and most load-velocity relationship parameters analyzed. A significant group × time interaction was observed for EMG root mean square in pectoralis major (P = .03) where only the VL25 group showed significant increases (P = .02). VL50 showed decreased EMG root mean square in triceps brachii (P = .006). Only the VL50 group showed significant increases in cross-sectional area (P < .001). CONCLUSIONS: These findings indicate that a VL threshold of about 25% with intensities from 55% to 70% 1RM in BP provides an optimal training stimulus to maximize dynamic strength performance and neuromuscular adaptations, while higher VL thresholds promote higher muscle hypertrophy.

Do Faster, Stronger, and More Powerful Athletes Perform Better in Resisted Sprints?

ABSTRACT: Lizana, JA, Bachero-Mena, B, Calvo-Lluch, A, Sánchez-Moreno, M, Pereira, LA, Loturco, I, and Pareja-Blanco, F. Do faster, stronger, and more powerful athletes perform better in resisted sprints? J Strength Cond Res 36(7): 1826-1832, 2022-This study aimed to analyze the relationships between different strength, power, and speed abilities and resisted sprint performance across a wide range of sled loads (10, 30, and 50% body mass [BM]). Seventy-nine young physically active male sport science students (age: 22.8 ± 3.4 years, BM: 74.2 ± 9.1 kg, and height: 175.4 ± 8.5 cm) performed 2 testing sessions. Session 1 consisted of a 20 m sprint without any additional load and with 10, 30, and 50% BM. Session 2 consisted of countermovement jump and full squat (SQ) tests. The CMJ was performed without any additional load and with loads of 30 and 50% BM, and the SQ was performed with loads corresponding to 30, 50, 70, and 90% BM. Resisted sprint times were moderate to large correlated with unloaded sprint times (r = 0.79 to 0.89), unloaded and loaded jump height (r = -0.62 to -0.71), and SQ performance (r = -0.56 to -0.71). Negative relationships were observed between velocity loss induced by each sled load and jump and SQ performance. The magnitude of these relationships increased with increasing sled loads. In conclusion, differences in speed, strength, and power abilities may explain, at least partially, the individual response of each athlete during sprinting towing a sled, especially with heavier sled loads. Thus, faster, stronger, and more powerful athletes require heavier sled loads (relative to %BM) to experience similar exercise intensities.

Acute Mechanical, Neuromuscular, and Metabolic Responses to Different Set Configurations in Resistance Training.

ABSTRACT: Piqueras-Sanchiz, F, Cornejo-Daza, PJ, Sánchez-Valdepeñas, J, Bachero-Mena, B, Sánchez-Moreno, M, Martín-Rodríguez, S, García-García, Ó, and Pareja-Blanco, F. Acute mechanical, neuromuscular, and metabolic responses to different set configurations in resistance training. J Strength Cond Res 36(11): 2983-2991, 2022-The aim of this study was to investigate the effect of set configuration on mechanical performance, neuromuscular activity, metabolic response, and muscle contractile properties. Sixteen strength-trained men performed 2 training sessions in the squat exercise consisting of (a) 3 sets of 8 repetitions with 5 minutes rest between sets (3 × 8) and (b) 6 sets of 4 repetitions with 2 minutes rest between sets (6 × 4). Training intensity (75% one repetition maximum), total volume (24 repetitions), total rest (10 minutes), and training density were equalized between protocols. A battery of tests was performed before and after each protocol: (a) tensiomyography (TMG), (b) blood lactate and ammonia concentration, (c) countermovement jump, and (d) maximal voluntary isometric contraction in the squat exercise. Force, velocity, and power output values, along with electromyography data, were recorded for every repetition throughout each protocol. The 6 × 4 protocol resulted in greater mechanical performance (i.e., force, velocity, and power) and lower neuromuscular markers of fatigue (i.e., lower root mean square and higher median frequency) during the exercise compared with 3 × 8, particularly for the last repetitions of each set. The 3 × 8 protocol induced greater lactate and ammonia concentrations, greater reductions in jump height, and greater impairments in TMG-derived velocity of deformation after exercise than 6 × 4. Therefore, implementing lower-repetition sets with shorter and more frequent interset rest intervals attenuates impairments in mechanical performance, especially in the final repetitions of each set. These effects may be mediated by lower neuromuscular alterations, reduced metabolic stress, and better maintained muscle contractile properties.

Effects of Velocity Loss Threshold Within Resistance Training During Concurrent Training on Endurance and Strength Performance.

PURPOSE: This study analyzed the effects of 3 training interventions: 1 isolated endurance training (ET) and 2 concurrent training (CT), which differed in the velocity loss (VL) magnitude allowed during the resistance training (RT) set: 15% (VL15) versus 45%, on strength and endurance running performance. METHODS: A total of 33 resistance- and endurance-trained men were randomly allocated into 3 groups: VL15, VL 45%, and ET. ET was similar across all groups. The CT groups differed in the VL allowed during the RT set. Before and after the 8-week training program the following tests were performed: (1) running sprints, (2) vertical jump, (3) progressive loading test in the squat exercise, and (4) incremental treadmill running test up to maximal oxygen uptake. RESULTS: Significant differences (P < .001) in RT volume (approximately 401 vs 177 total repetitions for VL 45% and VL15, respectively) were observed. Significant "group" × "time" interactions were observed for vertical jump and all strength-related variables: the CT groups attained significantly greater gains than ET. Moreover, a significant "group" × "time" interaction (P = .03) was noted for velocity at maximal oxygen uptake. Although all groups showed increases in velocity at maximal oxygen uptake, the VL15 group achieved greater gains than the ET group. CONCLUSIONS: CT interventions experienced greater strength gains than the ET group. Although all groups improved their endurance performance, the VL15 intervention resulted in greater gains than the ET approach. Therefore, moderate VL thresholds in RT performed during CT could be a good strategy for concurrently maximizing strength and endurance development.

Monitoring Training Volume Through Maximal Number of Repetitions or Velocity-Based Approach.

PURPOSE: This study aimed (1) to analyze the interindividual variability in the maximal number of repetitions (MNR) performed against a given relative load (percentage of 1-repetition maximum [%1RM]) and (2) to examine the relationship between the velocity loss (VL) magnitude and the percentage of completed repetitions with regard to the MNR (%Rep), when the %1RM is based on individual load-velocity relationships. METHODS: Following an assessment of 1RM strength and individual load-velocity relationships, 14 resistance-trained men completed 5 MNR tests against loads of 50%, 60%, 70%, 80%, and 90% 1RM in the Smith machine bench-press exercise. The relative loads were determined from the individual load-velocity relationship. RESULTS: Individual relationships between load and velocity displayed coefficients of determination (R2) ranging from .986 to .998. The MNR showed an interindividual coefficient of variation ranging from 8.6% to 33.1%, increasing as the %1RM increased. The relationship between %Rep and the magnitude of VL showed a general R2 of .92 to .94 between 50% and 80% 1RM, which decreased to .80 for 90% 1RM. The mean individual R2 values were between .97 and .99 for all loading conditions. The %Rep when a given percentage of VL was reached showed interindividual coefficient of variation values ranging from 5% to 20%, decreasing as the %Rep increased in each load condition. CONCLUSIONS: Setting a number of repetitions had acceptable interindividual variability, with moderate relative loads being adjusted based on the individual load-velocity relationship. However, to provide a more homogeneous level of effort between athletes, the VL approach should be considered, mainly when using individual VL-%Rep relationships.

Effects of Cluster Set Configuration on Mechanical Performance and Neuromuscular Activity.

ABSTRACT: Ortega-Becerra, M, Sánchez-Moreno, M, and Pareja-Blanco, F. Effects of cluster set configuration on mechanical performance and neuromuscular activity. J Strength Cond Res 35(2): 310-317, 2021-The aim of this study was to compare the effects of different cluster set (CS) configurations on mechanical performance and electromyography (EMG) activity during the bench press (BP) exercise. Fourteen strength-trained men (age 23.0 ± 2.4 years; height 1.76 ± 0.08 m; body mass 78.3 ± 12.2 kg) performed 3 different protocols in the BP exercise consisting of 3 sets of 12 repetitions at 60% of 1 repetition maximum with interset rests of 2 minutes, differing in the set configuration: (a) traditional sets (TRDs), (b) cluster sets of 4 repetitions (CS4), and (c) cluster sets of 2 repetitions (CS2). Intraset rests of 30 seconds were interposed for CS protocols. The mean propulsive values of force, velocity, and power output were measured for every repetition by synchronizing a linear velocity transducer with a force platform. The root mean square (RMS) and median frequency (MDF) for pectoralis major (PM) and triceps brachii (TB) muscles were also recorded for every repetition. Force, velocity, and power values progressively increased as the number of intraset rests increased (TRD < CS4 < CS2). The CS2 protocol exhibited lower RMS-PM than CS4 and TRD for almost all sets. In addition, TRDs showed significantly lower MDF-TB than CS2 for all sets and lower MDF-TB than CS4 during the third set. In conclusion, more frequent intraset rests were beneficial for maintaining mechanical performance, which may be mediated, from a neuromuscular perspective, by lesser increases in EMG amplitude and attenuated reductions in EMG frequency.

Effects of velocity loss in the bench press exercise on strength gains, neuromuscular adaptations, and muscle hypertrophy.

OBJECTIVE: This study aimed to compare the effects of four velocity-based training (VBT) programs in bench press (BP) between a wide range of velocity loss (VL) thresholds-0% (VL0), 15% (VL15), 25% (VL25), and 50% (VL50)-on strength gains, neuromuscular adaptations, and muscle hypertrophy. METHODS: Sixty-four resistance-trained young men were randomly assigned into four groups (VL0, VL15, VL25, and VL50) that differed in the VL allowed in each set. Subjects followed a VBT program for 8-weeks using the BP exercise. Before and after the VBT program the following tests were performed: (a) cross-sectional area (CSA) measurements of pectoralis major (PM) muscle; (b) maximal isometric test; (c) progressive loading test; and (d) fatigue test. RESULTS: Significant group x time interactions were observed for CSA (P < .01) and peak root mean square in PM (peak RMS-PM, P < .05). VL50 showed significantly greater gains in CSA than VL0 (P < .05). Only the VL15 group showed significant increases in peak RMS-PM (P < .01). Moreover, only VL0 showed significant gains in the early rate of force development (RFD, P = .05), while VL25 and VL50 improved in the late RFD (P ≤ .01-.05). No significant group × time interactions were found for any of the dynamic strength variables analyzed, although all groups showed significant improvements in all these parameters. CONCLUSION: Higher VL thresholds allowed for a greater volume load which maximized muscle hypertrophy, whereas lower VL thresholds evoked positive neuromuscular-related adaptations. No significant differences were found between groups for strength gains, despite the wide differences in the total volume accumulated by each group.

Acute and Short-Term Response to Different Loading Conditions During Resisted Sprint Training.

PURPOSE: To analyze the acute and short-term physical and metabolic responses to resisted sprint training with 5 different loading conditions (0%, 20%, 40%, 60%, and 80% body mass). METHODS: Fifteen male participants performed 8 × 20-m sprints with 2-minute rests between sprints with 5 different loading conditions. Subjects performed a battery of tests (creatine kinase and lactate concentrations, countermovement jump, 20-m sprint, and isokinetic knee extension and flexion contractions) at 3 different time points (preexercise [PRE], postexercise [POST], and 24-h postexercise [POST24H]). RESULTS: Results revealed significant increases in blood lactate for all loading conditions; however, as sled loadings increased, higher blood lactate concentrations and increments in sprint times during the training session were observed. Significant increases in creatine kinase concentration were observed from PRE to POST24H for all loading conditions. Concerning physical performance, significant decreases in countermovement-jump height from PRE to POST were found for all loading conditions. In addition, significant decreases in 20-m sprint performance from PRE to POST were observed for 0% (P = .05) and 80% (P = .02). No significant differences with PRE were observed for the physical-performance variables at POST24H, except for 20% load, which induced a significant decrease in mean power during knee flexion (P = .03). CONCLUSIONS: These results suggest that the higher the load used during resisted sprint training, the higher the physical-performance impairments and metabolic response produced, although all loading conditions led to a complete recovery of sprint performance at POST24H.

Effects of Velocity Loss During Body Mass Prone-Grip Pull-up Training on Strength and Endurance Performance.

Sánchez-Moreno, M, Cornejo-Daza, PJ, González-Badillo, JJ, and Pareja-Blanco, F. Effects of velocity loss during body mass prone-grip pull-up training on strength and endurance performance. J Strength Cond Res 34(4): 911-917, 2020-This study aimed to analyze the effects of 2 pull-up (PU) training programs that differed in the magnitude of repetition velocity loss allowed in each set (25% velocity loss "VL25" vs. 50% velocity loss "VL50") on PU performance. Twenty-nine strength-trained men (age = 26.1 ± 6.3 years, body mass [BM] = 74.2 ± 6.4 kg, and 15.9 ± 4.9 PU repetitions to failure) were randomly assigned to 2 groups: VL25 (n = 15) or VL50 (n = 14) and followed an 8-week (16 sessions) velocity-based BM prone-grip PU training program. Mean propulsive velocity (MPV) was monitored in all repetitions. Assessments performed at pre-training and post-training included estimated 1 repetition maximum; average MPV attained with all common external loads used during pre-training and post-training testing (AVinc); peak MPV lifting one's own BM (MPVbest); maximum number of repetitions to failure lifting one's own BM (MNR); and average MPV corresponding to the same number of repetitions lifting one's own BM performed during pre-training testing (AVMNR). VL25 attained significantly greater gains than VL50 in all analyzed variables except in MNR (P < 0.05). In addition, VL25 improved significantly (P < 0.001) in all the evaluated variables while VL50 remained unchanged. In conclusion, our results suggest that once a 25% velocity loss is achieved during PU training, further repetitions did not elicit additional gains and can even blunt the improvement in strength and endurance performance.

Velocity Loss as a Critical Variable Determining the Adaptations to Strength Training.

PURPOSE: This study aimed to compare the effects of four resistance training (RT) programs with different velocity loss (VL) thresholds: 0% (VL0), 10% (VL10), 20% (VL20), and 40% (VL40) on sprint and jump performance, muscle strength, neuromuscular, muscle hypertrophy, and architectural adaptations. METHODS: Sixty-four young resistance-trained men were randomly assigned into four groups (VL0, VL10, VL20, and VL40) that differed in the VL allowed in each set. Subjects followed an RT program for 8 wk (two sessions per week) using the full-squat (SQ) exercise, with similar relative intensity (70%-85% 1-repetition maximum), number of sets (3), and interset recovery period (4 min). Before and after the RT program, the following tests were performed: 1) muscle hypertrophy and architecture of the vastus lateralis (VLA), 2) tensiomyography, 3) 20-m running sprint, 4) vertical jump, 5) maximal voluntary isometric contraction in SQ, 6) progressive loading test in SQ, and 7) fatigue test. RESULTS: No between-group differences existed for RT-induced gains in sprint, jump, and strength performance despite the differences in the total volume performed by each group. VL20 and VL40 showed significant increases (P < 0.001) in muscle hypertrophy (group-time interaction, P = 0.06). However, only VL40 exhibited a significant slowing (P < 0.001) of the delay time in the VLA muscle (group-time interaction, P = 0.05). Moreover, VL40 showed a significant decrease in the early rate of force development (P = 0.04). CONCLUSIONS: Higher VL thresholds (i.e., VL20 and VL40) maximized hypertrophic adaptations, although an excessive VL during the set (i.e., VL40) may also induce negative neuromuscular adaptations. Therefore, moderate VL thresholds should be chosen to maximize strength adaptations and to prevent negative neuromuscular adaptations.

Effect of different inter-repetition rest intervals across four load intensities on velocity loss and blood lactate concentration during full squat exercise.

This study aimed to analyze the acute effect of inter-repetition rest (IRR) intervals on mechanical and metabolic response during four resistance exercise protocols (REPs). Thirty resistance-trained men were randomly assigned to: continuous repetitions (CR), 10 s (IRR10) or 20 s (IRR20) inter-repetition rest. The REPs consisted of 3 sets of 6, 5, 4 and 3 repetitions against 60, 70, 75 and 80% 1RM, respectively, in the full squat exercise. Muscle fatigue was assessed using: percentage of velocity loss over three sets, percentage of velocity loss against the ~1 m·s-1 load (V1 m·s-1), and loss of countermovement jump (CMJ) height pre-post exercise. Blood lactate was measured before and after exercise. The percentage of velocity loss over three sets and lactate concentration were significantly lower (P < 0.05) for IRR groups compared to CR in all REPs. The CR group showed a significantly higher (P < 0.05) velocity loss against V1 m·s-1 load and loss of CMJ height pre-post exercise than IRR groups in REP against 60% 1RM. In conclusion, both IRR groups produced a significant lower degree of fatigue compared to CR group. However, no significant differences were found in any measured variables between IRR configurations.

Movement Velocity as Indicator of Relative Intensity and Level of Effort Attained During the Set in Pull-Up Exercise.

PURPOSE: To analyze the relationship between movement velocity and relative load (%1RM) in the pull-up exercise (PU) and to determine the pattern of repetition-velocity loss during a single set to failure in pulling one's own body mass. METHODS: Fifty-two men (age = 26.5 ± 3.9 y, body mass = 74.3 ± 7.2 kg) performed a first evaluation (T1) consisting of an 1-repetition-maximum test (1RM) and a test of maximum number of repetitions to failure pulling one's own body mass (MNR) in the PU exercise. Thirty-nine subjects performed both tests on a second occasion (T2) following 12 wk of training. RESULTS: The authors observed a strong relationship between mean propulsive velocity (MPV) and %1RM (r = -.96). Mean velocity attained with 1RM load (V1RM) was 0.20 ± 0.05 m·s-1, and it influenced the MPV attained with each %1RM. Although 1RM increased by 3.4% from T1 to T2, the relationship between MPV and %1RM, and V1RM, remained stable. The authors also confirmed stability in the V1RM regardless of individual relative strength. The authors found a strong relationship between percentage of velocity loss and percentage of performed repetitions (R2 = .88), which remained stable despite a 15% increase in MNR. CONCLUSIONS: Monitoring repetition velocity allows estimation of the %1RM used as soon as the first repetition with a given load is performed, and the number of repetitions remaining in reserve when a given percentage of velocity loss is achieved during a PU exercise set.

Determinant factors of pull-up performance in trained athletes.

BACKGROUND: The aim of this study is to investigate the relationship among pull-up and lat pull exercises and different anthropometric dimensions in trained athletes. METHODS: Twenty-five males were evaluated for maximum number of pull-ups, one-repetition maximum lat pull (1RM Lat Pull), lat pull repetitions at 80% 1RM (Lat Pull at 80% 1RM), lat pull repetitions at a load equivalent to body mass (Lat Pull at BM-load), and different anthropometric variables. Furthermore, the subjects were divided in higher (HPG, N.=12) and lower pull-up performance (LPG, N.=13) to compare the differences in the variables analyzed between both levels. RESULTS: Pull-ups were significantly correlated with Lat Pull at BM-load (r=0.62, P<0.01) but neither with 1RM Lat Pull (r=0.09) nor with Lat Pull at 80% 1RM (r=-0.15). Pull-ups showed a significant (P<0.05) negative relationship with body mass (BM, r=-0.55), lean body mass (LBM, r=-0.51), and fat mass (FM, r=-0.52), while BM and LBM were significantly correlated with 1RM Lat Pull (r=0.55, P<0.05). HPG showed significantly (P<0.05) lower BM (0/3/97%), FM (1/3/97%) and LBM (1/4/95%) than LPG. Furthermore, HPG attained significantly (P<0.05 - 0.001) greater performance in Lat Pull at BM-load (100/0/0%) and 1RM Lat Pull/BM (96/3/2%) than LPG. CONCLUSIONS: These findings suggest that pull-up and lat pull exercises have common elements. Moreover, the anthropometric dimensions seem to influence differently on both exercises, depending on the strength indicator evaluated.