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1.
PeerJ ; 12: e17008, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464757

RESUMO

This study aimed to compare the mechanical (lifting velocity and maximum number of repetitions), physiological (muscular activation, lactate, heart rate, and blood pressure), and psychological (rating of perceived exertion) responses to upper-body pushing exercises performed wearing a sports elastomeric garment or a placebo garment. Nineteen physically active young adults randomly completed two training sessions that differed only in the sports garment used (elastomeric technology or placebo). In each session, subjects performed one set of seated shoulder presses and another set of push-ups until muscular failure. The dependent variables were measured immediately after finishing the set of each exercise. Compared to the placebo garment, the elastomeric garment allowed participants to obtain greater muscular activation in the pectoralis major (push-ups: p = 0.04, d = 0.49; seated shoulder press: p < 0.01, d = 0.64), triceps brachialis (push-ups, p < 0.01, d = 0.77; seated shoulder press: p < 0.01, d = 0.65), and anterior deltoid (push-ups: p < 0.01, d = 0.72; seated shoulder press: p < 0.01, d = 0.83) muscles. Similarly, participants performed more repetitions (push-ups: p < 0.01; d = 0.94; seated shoulder press: p = 0.03, d = 0.23), with higher movement velocity (all p ≤ 0.04, all d ≥ 0.47), and lower perceived exertion in the first repetition (push-ups: p < 0.01, d = 0.61; seated shoulder press: p = 0.05; d = 0.76) wearing the elastomeric garment compared to placebo. There were no between-garment differences in most cardiovascular variables (all p ≥ 0.10). Higher diastolic blood pressure was only found after the seated shoulder press wearing the elastomeric garment compared to the placebo (p = 0.04; d = 0.49). Finally, significantly lower blood lactate levels were achieved in the push-ups performed wearing the elastomeric garment (p < 0.01; d = 0.91), but no significant differences were observed in the seated shoulder press (p = 0.08). Overall, the findings of this study suggest that elastomeric technology integrated into a sports garment provides an ergogenic effect on mechanical, physiological, and psychological variables during the execution of pushing upper-limb resistance exercises.


Assuntos
Treinamento Resistido , Adulto Jovem , Humanos , Ombro/fisiologia , Levantamento de Peso/fisiologia , Lactatos , Vestuário
2.
Sports Health ; : 19417381241236808, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38544405

RESUMO

BACKGROUND: The aim of this study was to determine the influence of different percentages of blood flow restriction (BFR) and loads on mean propulsive velocity (MPV) and subjective perceived exertion during squat (SQ) and bench press (BP) exercises. HYPOTHESIS: Higher percentages of BFR will positively affect dependent variables, increasing MPV and reducing perceived exertion. STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 3. METHODS: Eight healthy young male athletes took part. Two sets of 6 repetitions at 70% 1-repetition maximum (1RM), 2 sets of 4 repetitions at 80% 1RM, and 2 sets of 2 repetitions at 90% 1RM were performed randomly; 5-minute recoveries were applied in all sets. The varying arterial occlusion pressure (AOP) applied randomly was 0% (Control [CON]), 80%, and 100%. RESULTS: No statistically significant differences in MPV were found during the BP exercise at any percentage of BFR at any percentage 1RM. During the SQ exercise, MPV results showed statistically significant increases of 5.46% (P = 0.04; ηp2 = 0.31) between CON and 100% AOP at 90% 1RM. The perceived exertion results for the BP exercise showed statistically significant reductions of -8.66% (P < 0.01; ηp2 = 0.06) between CON and 100% AOP at 90% 1RM. During the SQ exercise, the perceived exertion results showed significant reductions of -10.04% (P = 0.04; ηp2 = 0.40) between CON and 100% AOP at 80% 1RM; -5.47% (P = 0.02; ηp2 = 0.48) between CON and 80% AOP at 90% 1RM; and -11.83% (P < 0.01; ηp2 = 0.66) between CON and 100% AOP at 90% 1RM. CONCLUSION: BFR percentages ~100% AOP at 90% 1RM improved acutely MPV (only in SQ exercises) and reduced acutely perceived exertion (in both exercises). These findings are important to consider when prescribing resistance training for healthy male athletes.

3.
Sports (Basel) ; 11(11)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37999437

RESUMO

This study examined the force-velocity profile differences between men and women in three variations of row exercises. Twenty-eight participants (14 men and 14 women) underwent maximum dynamic strength assessments in the free prone bench row (PBR), bent-over barbell row (BBOR), and Smith machine bent-over row (SMBOR) in a randomized order. Subjects performed a progressive loading test from 30 to 100% of 1-RM (repetition maximum), and the mean propulsive velocity was measured in all attempts. Linear regression analyses were conducted to establish the relationships between the different measures of bar velocity and % 1-RM. The ANOVAs applied to the mean velocity achieved in each % 1-RM tested revealed significantly higher velocity values for loads < 65% 1-RM in SMBOR compared to BBOR (p < 0.05) and higher velocities for loads < 90% 1-RM in SMBOR compared to PBR (p < 0.05) for both sexes. Furthermore, men provided significantly higher velocity values than women (PBR 55-100% 1-RM; BBOR and SMBOR < 85% 1-RM; p < 0.05) and significant differences were found between exercises and sex for 30-40% 1-RM. These results confirm that men have higher velocities at different relative loads (i.e., % 1-RM) compared to women during upper-body rowing exercises.

4.
Sports (Basel) ; 11(6)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37368568

RESUMO

The purpose of this paper was to conduct a systematic review and meta-analysis of studies examining the differences in the mean propulsive velocities between men and women in the different exercises studied (squat, bench press, inclined bench press and military press). Quality Assessment and Validity Tool for Correlational Studies was used to assess the methodological quality of the included studies. Six studies of good and excellent methodological quality were included. Our meta-analysis compared men and women at the three most significant loads of the force-velocity profile (30, 70 and 90% of 1RM). A total of six studies were included in the systematic review, with a total sample of 249 participants (136 men and 113 women). The results of the main meta-analysis indicated that the mean propulsive velocity is lower in women than men in 30% of 1RM (ES = 1.30 ± 0.30; CI: 0.99-1.60; p < 0.001) and 70% of 1RM (ES = 0.92 ± 0.29; CI: 0.63, 1.21; p < 0.001). In contrast, for the 90% of the 1RM (ES = 0.27 ± 0.27; CI: 0.00, 0.55), we did not find significant differences (p = 0.05). Our results support the notion that prescription of the training load through the same velocity could cause women to receive different stimuli than men.

5.
J Funct Morphol Kinesiol ; 7(4)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36278740

RESUMO

The purpose of this study was to examine the type of relationship between measures of maximal force (dynamic and isometric), maximal power, and mean propulsive velocity. In total, 355 recreational athletes, 96 women (age 20.5 ± 2.5 years; height 158.2 ± 17.3 cm; weight 61.8 ± 48.4 kg) and 259 men (age 21.0 ± 2.6 years; height 170.5 ± 12.6 cm; weight 65.9 ± 9.2 kg) were evaluated in three sessions separated by 72 h each in isometric midthigh pull exercise (ISOS) (kg), bench press maximum strength (1RM MSBP) (kg), jump height (CMJ) (m), and maximum pedaling power (WT) the maximum squat strength (1RM MSS) (kg), the mean propulsive velocity in the bench press (MPVBP) (m·s-1), and the peak power (PPBP) (w), mean propulsive squat velocity (MPVS) (m·s-1), peak power (PP) (w), maximum handgrip force (ISOHG) (kg), and 30 m movement speed (V30) (s). Significant correlations (p ≤ 0.01) were identified between 95% of the various manifestations of force, and only 5% presented a significance of p ≤ 0.05; however, when the magnitude of these correlations is observed, there is great heterogeneity. In this sense, the dynamic strength tests present the best correlations with the other strength and power tests used in the present study, followed by PPBP and PP. The results of this study complement what is reported in the literature regarding the correlation between different types of force manifestations being heterogeneous and contradictory.

6.
Eur J Appl Physiol ; 122(5): 1269-1280, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35258681

RESUMO

PURPOSE: Men and women typically display different neuromuscular characteristics, force-velocity relationships, and differing strength deficit (upper vs. lower body). Thus, it is not clear how previous recommendations for training with velocity-loss resistance training based on data in men will apply to women. This study examined the inter-sex differences in neuromuscular adaptations using 20% and 40% velocity-loss protocols in back squat and bench press exercises. METHODS: The present study employed an 8-week intervention (2 × week) comparing 20% vs. 40% velocity-loss resistance training in the back squat and bench press exercises in young men and women (~ 26 years). Maximum strength (1-RM) and submaximal-load mean propulsive velocity (MPV) for low- and high-velocity lifts in squat and bench press, countermovement jump and vastus lateralis cross-sectional area were measured at pre-, mid-, and post-training. Surface EMG of quadriceps measured muscle activity during performance tests. RESULTS: All groups increased 1-RM strength in squat and bench press exercises, as well as MPV using submaximal loads and countermovement jump height (P < 0.05). No statistically significant between-group differences were observed, but higher magnitudes following 40% velocity loss in 1-RM (g = 0.60) and in low- (g = 1.42) and high-velocity (g = 0.98) lifts occurred in women. Training-induced improvements were accompanied by increases in surface EMG amplitude and vastus lateralis cross-sectional area. CONCLUSION: Similar increases in strength and power performance were observed in men and women over 8 weeks of velocity-based resistance training. However, some results suggest that strength and power gains favor using 40% rather than 20% velocity loss in women.


Assuntos
Treinamento Resistido , Adaptação Fisiológica , Exercício Físico , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Músculo Quadríceps , Treinamento Resistido/métodos
7.
J Sports Sci ; 40(9): 968-975, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35188434

RESUMO

Accuracy and test-retest reliability were assessed for two devices, PUSH Band 2.0 (PUSH) and Speed4lifts. Two identical sessions were performed 6-8 days apart. Twenty rugby league players performed three repetitions with 20%, 40%, 60% and 80% of estimated one repetition maximum for back squat (BS), front squat (FS), and bench press (BP). Velocity was recorded using PUSH, Speed4lifts and 3D motion analysis system (gold standard). Passing-Bablok regression analysis assessed agreement of velocity measures with the gold standard. Intraclass correlation coefficients (ICC) and coefficients of variation (CV) assessed test-retest reliability. PUSH and Speed4lifts were accurate for BS velocities <1.00 m/s and FS velocities <0.65 m/s. PUSH was accurate for BP velocities <0.65 m/s. Speed4lifts was accurate for BP velocities between 0.65-1.00 m/s. PUSH was reliable at all loads (ICC = 0.79-0.92; CV = 2.63-6.89%) except for 20% FS and BP (ICC = 0.49-0.64; CV = 3.13-3.62%). Speed4lifts was reliable at all loads (ICC = 0.70-0.96; CV = 2.57-4.26%) except for 20% BP (ICC = 0.59; CV = 4.59%). These results suggest that both devices are unsuitable for measuring the velocity of BS, FS and BP at faster velocities and at lighter loads.


Assuntos
Treinamento Resistido , Exercício Físico , Teste de Esforço/métodos , Humanos , Força Muscular , Reprodutibilidade dos Testes , Treinamento Resistido/métodos , Magreza , Levantamento de Peso
8.
Artigo em Inglês | MEDLINE | ID: mdl-34769679

RESUMO

Performance in wheelchair basketball is determined by capabilities, such as strength and power. The study has two aims: first, to analyze the association between speed and acceleration variables (collected in the bench press (BP) exercise) and the distinct percentages of one-repetition maximum (1RM); second, to analyze the effect of a strength training protocol on wheelchair basketball (WB) players according to their functional impairments. Ten Spanish male WB players volunteered to participate in the study. The players did a pretest and posttest (1RM in bench press) with 6-week muscle strength intervention program. The results showed a high association between the %1RM and the mean propulsive velocity (MPV) and the maximum velocity (Vmax), both in the total of the participants, and in each separate group of athletes. After implementing the strength training program, both the players of the IWBF (International Wheelchair Basketball Federation) < 2.5 group and those of IWBF > 2.5 group improved their 1RM (p < 0.01, ES = 0.20 to 0.23). However, the program produced positive effects at submaximal intensities in the MPV reached with 30, 40, 70, and 80 kg and in time to maximum velocity (TVmax) with 30, 40, and 70 kg (ES = -3.24 to 1.32) only in players with greater functional impairments. The high association between %1RM and MPV and Vmax can allow for determination the %1RM of the WB players in the BP using the MPV and the Vmax. The training program was effective in improving 1RM in both groups, while improvements in submaximal values only occurred in the IWBF < 2.5 group.


Assuntos
Basquetebol , Treinamento Resistido , Cadeiras de Rodas , Terapia por Exercício , Humanos , Masculino , Força Muscular , Músculo Esquelético
9.
Nutrients ; 13(3)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802283

RESUMO

This study assessed the effects of a 7-day creatine (CRE) supplementation on the load-velocity profile and repeated sub-maximal bouts in the deep squat using mean propulsive velocity (MPV) and mean propulsive power (MPP). Eleven strength-trained men (31.4 ± 5.4 years) supplemented 0.3 g·kg-1·d-1 CRE or a placebo (PLA, maltodextrin) for seven days in a randomized order, separated by a 30-day washout period. Prior to and after the supplementation, the subjects performed an incremental maximal strength (1RM) test, as well as 3 × 10 repetitions and a repetitions-to-failure test (RFT), all at 70% 1RM. Maximal strength remained statistically unaltered in CRE (p = 0.107) and PLA (p = 0.568). No statistical main effect for time (p = 0.780) or interaction (p = 0.737) was observed for the load-velocity profile. The number of repetitions during RFT remained statistically unaltered in both conditions (CRE: +16.8 ± 32.8%, p = 0.112; PLA: +8.2 ± 47.2%, p = 0.370), but the effect size was larger in creatine compared to placebo (g = 0.51 vs. g = 0.01). The total work during RFT increased following creatine supplementation (+23.1 ± 35.9%, p = 0.043, g = 0.70) but remained statistically unaltered in the placebo condition (+15.0 ± 60.8%, p = 0.801, g = 0.08; between conditions: p = 0.410, g = 0.25). We showed that CRE loading over seven days did not affect load-velocity characteristics but may have increased total work and power output during submaximal deep squat protocols, as was indicated by moderate effect sizes.


Assuntos
Creatina/administração & dosagem , Suplementos Nutricionais , Tolerância ao Exercício/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Suporte de Carga/fisiologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Força Muscular/efeitos dos fármacos , Treinamento Resistido/métodos
10.
Sports Biomech ; 20(2): 247-260, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30644796

RESUMO

This study aimed to compare the between-session reliability of three typically measured velocity variables (mean velocity [MV], mean propulsive velocity [MPV], and maximum velocity [Vmax]) to assess vertical jump performance. Totally, 23 men had their squat jump (SJ) and countermovement jump (CMJ) tested against five different loading conditions (17, 30, 45, 60 and 75 kg) during two consecutive weeks. The two sessions of each jump type were performed within the same week separated by 48-72 h. The main finding was a significant difference in reliability between the variables, which were ranked from the highest to the lowest reliable as follows (median coefficient of variation [CV] and range): Vmax (CV = 2.35% [1.85%-3.23%]) >MV (CV = 3.29% [2.18%-4.40%]) >MPV (CV = 3.69% [2.08%-5.17%]). A significant variable × exercise interaction was also observed showing that the differences in reliability between the variables were meaningful during the SJ (MV: CV = 3.93% [3.06%-4.40%], MPV: CV = 4.61% [4.07%-5.17%], and Vmax: CV = 2.14% [1.85%-2.71%]), while no significant differences were observed for the CMJ (MV: CV = 2.43% [2.18%-3.70%], MPV: CV = 2.71% [2.08%-3.63%], and Vmax: CV = 2.40% [1.97%-3.23%]). These results suggest that the Vmax should be the recommended variable for obtaining a reproducible measure of lower-body ballistic performance, especially during the SJ exercise.


Assuntos
Teste de Esforço/métodos , Exercício Pliométrico , Treinamento Resistido/métodos , Fenômenos Biomecânicos , Teste de Esforço/instrumentação , Humanos , Masculino , Reprodutibilidade dos Testes , Transdutores , Levantamento de Peso/fisiologia , Adulto Jovem
11.
J Hum Kinet ; 68: 81-98, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31531135

RESUMO

This study examined the acute effects of the bench press exercise with low and moderate loads as well as with two predetermined movement velocity loss percentages on bench press throw performance and surface electromyographic (sEMG) activity. Ten trained men completed 5 main trials in randomized and counterbalanced order one week apart. Mean propulsive velocity (MPV), peak velocity (PV) and sEMG activity of prime movers were evaluated before and periodically for 12 minutes of recovery under five conditions: using loads of 40 or 60% of 1 RM, until mean velocity dropped to 90 or 70%, as well as a control condition (CTRL). MPV and PV were increased 4-12 min into recovery by 4.5-6.8% only after the 60%1RM condition during which velocity dropped to 90% and total exercise volume was the lowest of all conditions (p < 0.01, Hedges' g = 0.8-1.7). When peak individual responses were calculated irrespective of time, MPV was increased by 9.2 ± 4.4 (p < 0.001, Hedges' g = 1.0) and 6.1 ± 3.6% (p < 0.001, Hedges' g = 0.7) under the two conditions with the lowest total exercise volume irrespective of the load, i.e. under the conditions of 40 and 60% 1RM where velocity was allowed to drop to 90%. sEMG activity of the triceps was significantly greater when peak individual responses were taken into account only under the 60%1RM condition when velocity dropped to 90% (p < 0.05, Hedges' g = 0.4). This study showed that potentiation may be maximized by taking into account individual fatigue profiles using velocity-based training.

12.
Int J Sports Physiol Perform ; 13(6): 763-769, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29140148

RESUMO

PURPOSE: To examine the reliability of peak velocity (PV), mean propulsive velocity (MPV), and mean velocity (MV) in the development of load-velocity profiles (LVP) in the full-depth free-weight back squat performed with maximal concentric effort. METHODS: Eighteen resistance-trained men performed a baseline 1-repetition maximum (1-RM) back-squat trial and 3 subsequent 1-RM trials used for reliability analyses, with 48-h intervals between trials. 1-RM trials comprised lifts from 6 relative loads including 20%, 40%, 60%, 80%, 90%, and 100% 1-RM. Individualized LVPs for PV, MPV, or MV were derived from loads that were highly reliable based on the following criteria: intraclass correlation coefficient (ICC) >.70, coefficient of variation (CV) ≤10%, and Cohen d effect size (ES) <0.60. RESULTS: PV was highly reliable at all 6 loads. MPV and MV were highly reliable at 20%, 40%, 60%, 80%, and 90% but not 100% 1-RM (MPV: ICC = .66, CV = 18.0%, ES = 0.10, SEM = 0.04 m·s-1; MV: ICC = .55, CV = 19.4%, ES = 0.08, SEM = 0.04 m·s-1). When considering the reliable ranges, almost perfect correlations were observed for LVPs derived from PV20-100% (r = .91-.93), MPV20-90% (r = .92-.94), and MV20-90% (r = .94-.95). Furthermore, the LVPs were not significantly different (P > .05) between trials or movement velocities or between linear regression versus 2nd-order polynomial fits. CONCLUSIONS: PV20-100%, MPV20-90%, and MV20-90% are reliable and can be utilized to develop LVPs using linear regression. Conceptually, LVPs can be used to monitor changes in movement velocity and employed as a method for adjusting sessional training loads according to daily readiness.


Assuntos
Treinamento Resistido/métodos , Levantamento de Peso/fisiologia , Adulto , Fenômenos Biomecânicos , Humanos , Modelos Lineares , Masculino , Movimento , Reprodutibilidade dos Testes
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