Impact of movement tempo on bar velocity and time under tension in resistance exercises with different external loads.

The goal of the study was to determine the differences between volitional and maximal movement tempo during resistance exercise. Ten healthy men volunteered for the study (age = 26.4 ± 4.8 years; body mass = 93.8 ± 9.6 kg; barbell squat one-repetition maximum (1RM) = 175 ± 16.7 kg; bench press 1RM = 140.5 ± 26.8 kg). In a randomized order, the participants performed six sets of the barbell squat and the bench press exercise at progressive loads from 40% to 90%1RM (step by 10%) under two testing conditions: with volitional movement tempo or with maximal movement tempo. The three-way repeated measures ANOVA showed a statistically significant multi-interaction effect for time under tension (p < 0.001), peak bar velocity (p = 0.04) and for mean bar velocity (p < 0.001). There was also a statistically significant main effect of movement tempo for time under tension (p < 0.001), peak bar velocity (p < 0.001) and for mean bar velocity (p < 0.001). The post hoc analysis for main effect of tempo revealed that time under tension was significantly longer for volitional compared to maximal tempo (0.84 vs 0.67 s, respectively), peak bar velocity was significantly higher for maximal compared to volitional tempo (1.24 m/s vs 0.90 m/s, respectively), and mean bar velocity was significant higher for maximal compared to volitional tempo (0.84 m/s vs 0.67 m/s, respectively). The presented results indicate that there were significant differences between volitional and maximal movement tempos in time under tension and bar velocity (peak and mean), as well as significant differences in those variables between the two exercises. Therefore, the velocity of movement and time under tension is related to movement tempo, external load and type of exercise used.

Acute impact of blood flow restriction on strength-endurance performance during the bench press exercise.

The main goal of the present study was to evaluate the acute effects of blood flow restriction (BFR) at 70% of full arterial occlusion pressure on strength-endurance performance during the bench press exercise. The study included 14 strength-trained male subjects (age = 25.6 ± 4.1 years; body mass = 81.7 ± 10.8 kg; bench press 1 repetition maximum (1RM) = 130.0 ± 22.1 kg), experienced in resistance training (3.9 ± 2.4 years). During the experimental sessions in a randomized crossover design, the subjects performed three sets of the bench press at 80% 1RM performed to failure with two different conditions: without BFR (CON); and with BFR (BFR). Friedman's test showed significant differences between BFR and CON conditions for the number of repetitions performed (p < 0.001); for peak bar velocity (p < 0.001) and for mean bar velocity (p < 0.001). The pairwise comparisons showed a significant decrease for peak bar velocity and mean bar velocity in individual Set 1 for BFR when compared to CON conditions (p = 0.01 for both). The two-way repeated measures ANOVA showed a significant main effect for the time under tension (p = 0.02). A post-hoc comparisons for the main effect showed a significant increase in time under tension for BFR when compared to CON (p = 0.02). The results of the presented study indicate that BFR used during strength-endurance exercise generally does not decrease the level of endurance performance, while it causes a drop in bar velocity.

Fast Eccentric Movement Tempo Elicits Higher Physiological Responses than Medium Eccentric Tempo in Ice-Hockey Players.

BACKGROUND: Resistance training is a significant part of ice-hockey players' conditioning, where optimal loading should ensure strength development and proper recovery. Therefore, this study aimed to compare the acute physiological responses to fast and medium movement tempo resistance exercises in ice-hockey players. METHODS: Fourteen ice-hockey players (26.2 ± 4.2 years; 86.4 ± 10.2 kg; squat one repetition maximum (1RM) = 130.5 ± 18.5) performed five sets of the barbell squat and barbell bench press at 80% 1RM until failure in a crossover design one week apart using either 2/0/2/0 or 6/0/2/0 (eccentric/isometric/concentric/isometric) tempo of movement. The blood samples to evaluate the concentration of cortisol, testosterone, insulin-like growth factor 1 (IGF-1), and growth hormone (hGH) were taken before exercise, 3 min after the last set of the squat exercise, 3 min after the last set of the bench press exercise, and after 30 min of recovery. RESULTS: The 2/0/2/0 tempo resulted in a higher number of repetitions (p < 0.001) and lower time under tension (p < 0.001) in the squat and bench press exercises compared to the 6/0/2/0 movement tempo. The endocrine responses to exercise were significantly higher during the 2/0/2/0 compared to the 6/0/2/0 movement tempo protocol for IGF-1, hGH, and cortisol (p < 0.01). There were no differences in testosterone responses between exercises performed with fast and medium movement tempos. CONCLUSION: Fast eccentric tempo induced higher cortisol, IGF-1, and hGH responses compared to the medium tempo. Therefore, fast eccentric movement tempo seems to be more useful in eliciting training stimulus than medium eccentric tempo during resistance training in ice-hockey players. However, future studies are needed to confirm our findings.

Acute Effects of Continuous and Intermittent Blood Flow Restriction on Movement Velocity During Bench Press Exercise Against Different Loads.

This study evaluated the effects of continuous and intermittent blood flow restriction (BFR) with 70% of full arterial occlusion pressure on bar velocity during the bench press exercise against a wide range of resistive loads. Eleven strength-trained males (age: 23.5 ± 1.4 years; resistance training experience: 2.8 ± 0.8 years, maximal bench press strength - 1RM = 101.8 ± 13.9 kg; body mass = 79.8 ± 10.4 kg), performed three different testing protocols in random and counterbalanced order: without BFR (NO-BFR); intermittent BFR (I-BFR) and continuous BFR (C-BFR). During each experimental session, subjects performed eight sets of two repetitions each, with increasing loads from 20 to 90% 1RM (10% steps), and 3 min rest between each set. In the C-BFR condition occlusion was kept throughout the trial, while in the I-BFR, occlusion was released during each 3 min rest interval. Peak bar velocity (PV) during the bench press exercise was higher by 12-17% in both I-BFR and C-BFR compared with NO-BFR only at the loads of 20, 30, 40, and 50% 1RM (p < 0.001), while performance at higher loads remained unchanged. Mean bar velocity (MV) was unaffected by occlusion (p = 0.342). These results indicate that BFR during bench press exercise increases PV and this may be used as an enhanced stimulus during explosive resistance training. At higher workloads, bench press performance was not negatively affected by BFR, indicating that the benefits of exercise under occlusion can be obtained while explosive performance is not impaired.

The Use of Different Modes of Post-Activation Potentiation (PAP) for Enhancing Speed of the Slide-Step in Basketball Players.

Background: This study aimed to determine whether 5% of body mass-resisted or assisted conditioning activity (CA) can enhance 5 m slide-step movement performance. Methods: Sixteen division I basketball players participated in this study (23.6 ± 4.4 years; 86.3 ± 5.9 kg; 192.3 ± 6.2 cm; training experience 6.7 ± 2.6 years). The experiment was performed following a randomized crossover design, where each participant performed two different exercise protocols-assisted and resisted CA each consisting of four sets of 10 m slide-step movement with 5% of body mass external load and 1 min rest intervals between. To assess the differences between baseline and post-assisted, as well as post-resisted CA, the participants performed a 2 × 5 m slide-step movement 6 min after each CA protocol. The differences in time between baseline, post-assisted and post-resisted CA were examined using repeated-measures ANOVA. Results: ANOVA indicated a statistically significant difference between baseline and post-assisted postactivation performance enhancement (PAPE) (p = 0.011). There were no significant intragroup differences between baseline and post-resisted CA (p = 0.230). Conclusion: Findings of the study show that a light load assisted CA (5% of body mass) effectively elicits a potentiation response among basketball players.

The Acute Impact of External Compression on Back Squat Performance in Competitive Athletes.

The aim of the present study was to evaluate the effects of external compression with blood flow restriction on power output and bar velocity changes during the back-squat exercise (SQ). The study included 10 judo athletes (age = 28.4 ± 5.8 years; body mass = 81.3 ± 13.1 kg; SQ one-repetition maximum (1-RM) 152 ± 34 kg; training experience 10.7 ± 2.3 years). METHODS: The experiment was performed following a randomized crossover design, where each participant performed three different exercise protocols: (1) control, without external compression (CONT); (2) intermittent external compression with pressure of 100% arterial occlusion pressure (AOP) (EC-100); and (3) intermittent external compression with pressure of 150% AOP (EC-150). To assess the differences between conditions, the participants performed 3 sets of 3 repetitions of the SQ at 70% 1-RM. The differences in peak power output (PP), mean power output (MP), peak bar velocity (PV), and mean bar velocity (MV) between the three conditions were examined using repeated measures two-way ANOVA. RESULTS: The post hoc analysis for the main effect of conditions showed a significant increase in PP (p = 0.03), PV (p = 0.02), MP (p = 0.04), and MV (p = 0.03), for the EC-150, compared to the CONT. Furthermore, a statistically significant increase in PP (p = 0.04), PV (p = 0.03), MP (p = 0.02), and MV (p = 0.01) were observed for the EC-150 compared to EC-100. There were no significant changes in PP, PV, MP, and MV, between EC-100 and CONT conditions. CONCLUSION: The results indicate that the use of extremely high-pressure external compression (150% AOP) during high-loaded (70% 1-RM) lower limb resistance exercise elicits an acute increase in power output and bar velocity.

Impact of Duration of Eccentric Movement in the One-Repetition Maximum Test Result in the Bench Press among Women.

Scientific studies related to resistance training have considered many variables; however, the tempo of movement of particular repetitions is often neglected or not reported in resistance training practice and research. The aim of the study was to determine the effect of different duration of the eccentric (ECC) phase of movement on one-repetition maximum test (1RM) results during the bench press exercise (BP). Twenty-one strength trained females (age = 23.4 ± 2.2 years, body mass = 52.3 ± 6.7 kg), with a minimum one year of strength training experience took part in the study. The experiment was conducted following a randomized crossover design, where each participant completed the 1RM test in the BP with three different duration times of the ECC movement: 2/0/X, 4/0/X, 6/0/X. Concentric (CON) movement was performed with maximal velocity (X). The ANOVA with repeated measures were used to compare the differences between the analyzed variables. The results of the study indicated the maximal load in the 1RM test was significantly higher during the BP with the 2/0/X tempo compared to 6/0/X (p < 0.01) and 4/0/X tempos (p < 0.01). Therefore, the results indicated that the longer the duration of the ECC phase of movement, the greater the decrease in the result of the 1RM test. The 1RM test procedure should include information about the movement tempo used during the test protocol.

The effects of resistance training experience on movement characteristics in the bench press exercise.

The main aim of this study was to determine whether the level of experience in strength training has a significant effect on differences in the value of exercise volume determined on time under tension (TUT) and number of repetition (REP) for a specific movement tempo. The study examined 68 men divided into groups of beginners and advanced strength trained athletes. The participants performed 5 sets of bench press (BP) at 70% 1RM using either a REG, MED or SLOW metronome guided cadence. Each set was performed to failure and with 3 min of rest between sets. Significant differences in TUT were found between the groups of beginners and advanced athletes for the slow (SLO) 6/0/4/0 tempo in set 1 (p = 0.01) and set 2 (p = 0.04), and for the regular (REG) 2/0/2/0 tempo in set 5 (p = 0.01). Significant differences were documented for total TUT between the beginners and advanced athletes for the SLO 6/0/4/0 tempo (p = 0.04). The results of ANOVA revealed significant differences in the number of repetitions between groups for the SLO 6/0/4/0 tempo in set 4 (p = 0.04) and set 5 (p = 0.04), and for the REG 2/0/2/0 tempo in set 5 (p = 0.01). The main finding of this study is that strength training experience has a significant effect on training volume, both in terms of TUT and REP at a specific constant movement tempo. Significant differences do not occur for each value of the tempo used.

Acute Caffeine Intake Enhances Mean Power Output and Bar Velocity during the Bench Press Throw in Athletes Habituated to Caffeine.

BACKGROUND: The main objective of the current investigation was to evaluate the effects of caffeine on power output and bar velocity during an explosive bench press throw in athletes habituated to caffeine. METHODS: Twelve resistance trained individuals habituated to caffeine ingestion participated in a randomized double-blind experimental design. Each participant performed three identical experimental sessions 60 min after the intake of a placebo, 3, and 6 mg/kg/b.m. of caffeine. In each experimental session, the participants performed 5 sets of 2 repetitions of the bench press throw (with a load equivalent to 30% repetition maximum (RM), measured in a familiarization trial) on a Smith machine, while bar velocity and power output were registered with a rotatory encoder. RESULTS: In comparison to the placebo, the intake of caffeine increased mean bar velocity during 5 sets of the bench press throw (1.37 ± 0.05 vs. 1.41 ± 0.05 and 1.41 ± 0.06 m/s for placebo, 3, and 6 mg/kg/b.m., respectively; p < 0.01), as well as mean power output (545 ± 117 vs. 562 ± 118 and 560 ± 107 W; p < 0.01). However, caffeine was not effective at increasing peak velocity (p = 0.09) nor peak power output (p = 0.07) during the explosive exercise. CONCLUSION: The acute doses of caffeine before resistance exercise may increase mean power output and mean bar velocity during the bench press throw training session in a group of habitual caffeine users. Thus, caffeine prior to ballistic exercises enhances performance during a power-specific resistance training session.

The Influence of Grip Width on Training Volume During the Bench Press with Different Movement Tempos.

The aim of the study was to determine the effect of the wide-grip bench press (WGBP) and the close-grip bench press (CGBP) on the number of performed repetitions (REPs) and time under tension (TUT) using a variable tempo of movement. Twenty (20) women experienced in resistance training were enrolled in the study (1RM-CGBP = 55.2 ± 9.5 kg; 1RM-WGBP = 52.7 ± 8.5 kg). Participants performed 5 sets of the BP with a maximal number of REPs at 70%1RM. Different tempos of movement, i.e., slow (6/0/X/0) and fast (2/0/X/0), and grip widths, i.e., the CGBP and the WGBP, were employed. The following variables were registered: maximal number of repetitions in every set (REPSet1-5), total number of repetitions performed in 5 sets (TREP), maximal time under tension in every set (TUTSet1-5) and total time under tension in 5 sets (TTUT). The two-way ANOVA revealed statistically significant differences between the WGBPFAST and the WGBPSLOW in TUTSet1-5 (p < 0.05) and TTUT (p < 0.01), as well as between the CGBPFAST and the CGBPSLOW in TUTSet1-5 (p < 0.01) and TTUT (p < 0.01). Significant differences between the WGBPFAST and the WGBPSLOW were also observed in REPSet1-5 (p < 0.01) and TREP (p < 0.01) as well as between the CGBPFAST and the CGBPSLOW in REPSet1-5 (p < 0.01) and TREP (p < 0.01). No significant differences between the WGBPSLOW and the CGBPSLOW nor the WGBPFAST and the CGBPFAST were found. The study demonstrates that the tempo of movement, regardless of the width grip, has a significant effect on the volume of effort in resistance training.

Technical and Training Related Aspects of Resistance Training Using Blood Flow Restriction in Competitive Sport - A Review.

Blood flow restriction (BFR) combined with resistance training (RT-BFR) shows significant benefits in terms of muscle strength and hypertrophy. Such effects have been observed in clinical populations, in groups of physically active people, and among competitive athletes. These effects are comparable or, in some cases, even more efficient compared to conventional resistance training (CRT). RT-BFR stimulates muscle hypertrophy and improves muscle strength even at low external loads. Since no extensive scientific research has been done in relation to groups of athletes, the aim of the present study was to identify technical, physiological and methodological aspects related to the use of RT-BFR in competitive athletes from various sport disciplines. RT-BFR in groups of athletes has an effect not only on the improvement of muscle strength or muscle hypertrophy, but also on specific motor abilities related to a particular sport discipline. The literature review reveals that most experts do not recommend the use RT-BFR as the only training method, but rather as a complementary method to CRT. It is likely that optimal muscle adaptive changes can be induced by a combination of CRT and RT-BFR. Some research has confirmed benefits of using CRT followed by RT-BFR during a training session. The use of BFR in training also requires adequate progression or modifications in the duration of occlusion in a training session, the ratio of exercises performed with BFR to conventional exercises, the value of pressure or the cuff width.