Interset Rest Research Articles

Variations in mean propulsive velocity responses during bench press exercise across different inter-set rest intervals

Variations in mean propulsive velocity responses during bench press exercise across different inter-set rest intervals

The Effect of Different Resistance Training Protocols on Cardiac Autonomic Modulation During Exercise Recovery: A Crossover, Randomized, and Controlled Pilot Study

Purpose: This study investigated the impact of two different resistance training (RT) protocols on cardiac autonomic modulation during exercise recovery in trained individuals. It was hypothesized that a hypertrophic resistance training program would induce more significant stress and negatively affect cardiac autonomic modulation compared to a power/force resistance training program. Methods: Six healthy, trained participants (aged 18–40) were randomized in a crossover and controlled pilot study. Participants performed two RT protocols: (i) three sets of 10 repetitions with 85% of 10 RM, 60 s inter-set rest (3x1060s) and (ii) eight sets of three repetitions with 85% of 3 RM, 120 s inter-set rest (8x3120s). Heart rate variability (HRV) was measured before and 30 min after each RT session. Results: Significant reductions in HRV parameters (RMSSD, HF, and SD1) were observed following the 3x1060s protocol (hypertrophic design) compared to baseline. Conversely, the 8x3120s (power/force design) protocol did not show significant changes in HRV parameters. A significant interaction effect for time and RT protocol was found for all HRV measures with more significant reductions observed after 3x1060s compared to 8x3120s. Conclusions: The hypertrophic RT session (3x1060s) significantly reduced HRV parameters, suggesting higher physiological stress and potentially negative implications for cardiac autonomic recovery than the power/force RT session (8x3120s). These findings highlight the importance of considering exercise intensity and protocol design to manage cardiac autonomic stress during resistance training.

Give it a rest: a systematic review with Bayesian meta-analysis on the effect of inter-set rest interval duration on muscle hypertrophy.

We systematically searched the literature for studies with a randomized design that compared different inter-set rest interval durations for estimates of pre-/post-study changes in lean/muscle mass in healthy adults while controlling all other training variables. Bayesian meta-analyses on non-controlled effect sizes using hierarchical models of all 19 measurements (thigh: 10; arm: 6; whole body: 3) from 9 studies meeting inclusion criteria analyses showed substantial overlap of standardized mean differences across the different inter-set rest periods [binary: short: 0.48 (95%CrI: 0.19-0.81), longer: 0.56 (95%CrI: 0.24-0.86); Four categories: short: 0.47 (95%CrI: 0.19-0.80), intermediate: 0.65 (95%CrI: 0.18-1.1), long: 0.55 (95%CrI: 0.15-0.90), very long: 0.50 (95%CrI: 0.14-0.89)], with substantial heterogeneity in results. Univariate and multivariate pairwise meta-analyses of controlled binary (short vs. longer) effect sizes showed similar results for the arm and thigh with central estimates tending to favor longer rest periods [arm: 0.13 (95%CrI: -0.27 to 0.51); thigh: 0.17 (95%CrI: -0.13 to 0.43)]. In contrast, central estimates closer to zero but marginally favoring shorter rest periods were estimated for the whole body [whole body: -0.08 (95%CrI: -0.45 to 0.29)]. Subanalysis of set end-point data indicated that training to failure or stopping short of failure did not meaningfully influence the interaction between rest interval duration and muscle hypertrophy. In conclusion, results suggest a small hypertrophic benefit to employing inter-set rest interval durations >60 s, perhaps mediated by reductions in volume load. However, our analysis did not detect appreciable differences in hypertrophy when resting >90 s between sets, consistent with evidence that detrimental effects on volume load tend to plateau beyond this time-frame. Systematic Review Registration: OSF, https://doi.org/10.17605/OSF.IO/YWEVC.

Effect of a new resistance training method on the metaboreflex in cardiac rehabilitation patients: a randomized controlled trial.

Patients with cardiac disease exhibit exaggerated sympathoexcitation, pressor, and ventilatory responses to muscle metaboreflex activation (MMA). However, the effects of cardiac rehabilitation (CR) and especially resistance training (RT) modalities on MMA are not well known. This study investigated how CR impacts MMA in such patients, specifically examining the effects of two different resistance training (RT) protocols following 12weeks of CR. In addition to endurance exercises, 32 patients were randomized into either a 3/7 RT modality (comprising 5 sets of 3-7 repetitions) or a control (CTRL) modality (involving 3 sets of 9 repetitions), with distinct inter-set rest intervals (15s for 3/7 and 60s for CTRL). MMA, gauged by blood pressure (BP) and ventilatory (Ve) responses during a handgrip exercise at 40% effort and subsequent post-exercise circulatory occlusion, demonstrated CR's significant impact. Systolic BP, initially at + 28 ± 23% pre-CR, improved to + 11 ± 15% post-CR (P = .011 time effect; P = .131 group effect). Diastolic BP showed a similar trend, from + 27 ± 23% to + 13 ± 15% (P = .099 time effect; P = .087 group effect). Ve, initially at + 60 ± 39%, reduced to + 14 ± 19% post-CR (P < .001 time effect; P = .142 group effect). Critical parameters-maximal oxygen consumption, lean mass, hand grip, and quadriceps strength-exhibited parallel increases in both 3/7 and CTRL groups (P < .05 time effect; P > .3 group effect). Ultimately, CR demonstrated comparable improvements in MMA across both RT modalities, indicating its positive influence on cardiovascular responses and physical performance in individuals with cardiac conditions.

Enhancing lower limb and core muscle activation with blood flow restriction training: a randomized crossover study on high-intensity squat exercises.

The primary objective of this study was to assess the impact of high-intensity deep squat training integrated with various blood flow restriction (BFR) modalities on the activation of lower limb and core muscles. A randomized, self-controlled crossover experimental design was employed with 12 participants. The exercise protocol consisted of squat training at 75% of one-repetition maximum (1RM), performed in 3 sets of 8 repetitions with a 2-min inter-set rest period. This was conducted under four distinct BFR conditions: continuous low BFR (T1), intermittent medium BFR (T2), intermittent high BFR (T3), and a non-restricted control (C). Surface electromyography (EMG) was utilized to collect EMG signals from the target muscles during the BFR and squat training sessions. The root mean square (RMS) amplitude standard values were calculated for each squat set to quantify muscle activation levels, with these values expressed as a percentage of the maximum voluntary contraction (%MVC). Rating of Perceived Exertion was evaluated after each squat set, and leg circumference measurements were taken. 1) During the first two sets of deep squats, the %MVC of the vastus lateralis and vastus medialis in all compression groups was significantly higher than that in the control group (p < 0.05). Furthermore, in the first set, the %MVC of the vastus lateralis in Group T3 was significantly higher than in Group T2 (p < 0.05). In the third set, the %MVC of the vastus medialis in Groups T1 and T3 was significantly lower than in the first two sets (p < 0.05). 2) Group T1 showed an increased activation of the biceps femoris and semitendinosus muscles in the second and third sets, with %MVC values significantly greater than in the first set (p < 0.05). Group T2 only showed an increase in biceps femoris activation in the third set (p < 0.05). Group T3 significantly increased the activation of the biceps femoris and semitendinosus muscles only in the first set (p < 0.05). 3) No significant differences were observed in the changes of rectus abdominis %MVC among the groups (p > 0.05). In the first set, Group T3's erector spinae %MVC was significantly higher than the control group's; in the second set, it was significantly higher than both Group T2 and the control group's (p < 0.05). 4) After training, a significant increase in thigh circumference was observed in all groups compared to before training (p < 0.05). 5) For RPE values, Group T2's post-squat values were significantly higher than the control group's after all three sets (p < 0.05). Group T1's RPE values were also significantly higher than the control group's after the third set (p < 0.05). Groups T1, T2, and C all had significantly higher RPE values in the second and third sets compared to the first set (p < 0.05). All BFR modalities significantly enhanced the activation level of the anterior thigh muscles, with the continuous low BFR mode demonstrating a more stable effect. No significant differences were found in the activation level of the rectus abdominis among the groups. However, the intermittent high BFR mode was the most effective in increasing the activation level of the erector spinae muscles. While BFR did not further augment leg circumference changes, it did elevate subjective fatigue levels. The RPE was lowest during squatting under the intermittent high BFR condition.

Exercise responses to repeated cycle sprints with continuous and intermittent hypoxic exposure.

We examine the impact of the acute manipulation of oxygen availability during discrete phases (active and passive) of a repeated-sprint cycling protocol on performance, physiological, and perceptual responses. On separate days, twelve trained males completed four sets of five 5-s 'all out' cycle sprints (25-s inter-sprint recovery and 5-min interset rest) in four randomized conditions: normobaric hypoxia (inspired oxygen fraction of 12.9%) applied continuously (C-HYP), intermittently during only the sets of sprints (I-HYPSPRINT) or between-sets recovery periods (I-HYPRECOVERY), or not at all (C-NOR). Peak and mean power output, peripheral oxygen saturation, heart rate, blood lactate concentration, exercise-related sensations, and vastus lateralis muscle oxygenation using near-infrared spectroscopy were assessed. Peak and mean power output was ∼4%-5% lower for C-HYP compared to C-NOR (P≤0.050) and I-HYPRECOVERY (P≤0.027). Peripheral oxygen saturation was lower during C-HYP and I-HYPSPRINT compared with C-NOR and I-HYPRECOVERY during sets of sprints (∼83-85 vs. ∼95%-97%; P<0.001), while lower values were obtained for C-HYP and I-HYPRECOVERY than C-NOR and I-HYPSPRINT during between-sets rest period (∼84-85 vs. ∼96%; P<0.001). Difficulty in breathing was ∼21% higher for C-HYP than C-NOR (P=0.050). Ratings of perceived exertion (P=0.435), limb discomfort (P=0.416), heart rate (P=0.605), blood lactate concentration (P=0.976), and muscle oxygenation-derived variables (P=0.056 to 0.605) did not differ between conditions. In conclusion, the method of hypoxic exposure application (continuous vs. intermittent) affects mechanical performance, while internal demands remained essentially comparable during repeated cycle sprints.

The Autoregulation Rest-Redistribution Training Method Mitigates Sex Differences in Neuromuscular and Perceived Fatigue During Resistance Training.

To examine the sex differences in performance and perceived fatigue during resistance training prescribed using traditional (TRA) and autoregulation rest-redistribution training (ARRT) approaches. Twelve resistance-trained men and 12 women completed 2 sessions including the bench-press exercise matched for load (75% of 1-repetition maximum), volume (24 repetitions), and total rest (240s). Sessions were performed in a counterbalanced randomized design with TRA consisting of 3 sets of 8 repetitions with 120-second interset rest and ARRT employing a personalized combination of clusters, repetitions per cluster, and between-clusters rest regulated with a 20% velocity-loss threshold. The effects of TRA and ARRT on velocity loss, unilateral isometric peak force, and rating of fatigue (ROF) were compared between sexes. The velocity loss was generally lower during ARRT compared with TRA (-0.47% [0.11%]), with velocity loss being mitigated by ARRT to a greater extent among males compared with females (-0.37% [0.15%]). A smaller unilateral isometric peak force decline was observed after ARRT than TRA among males compared with females (-38.4 [8.4]N). Lower ROF after ARRT than TRA was found among males compared to females (-1.97 [0.55]AU). Additionally, males reported greater ROF than females across both conditions (1.92 [0.53]AU), and ARRT resulted in lower ROF than TRA overall (-0.83 [0.39]AU). The ARRT approach resulted in decreased velocity loss, peak force impairment, and ROF compared with TRA in both sexes. However, male subjects exhibited more pronounced acute within-session benefits from the ARRT method.

Muscle Strength Preservation During Repeated Sets of Fatiguing Resistance Exercise: A Secondary Analysis.

Nuzzo, JL. Muscle strength preservation during repeated sets of fatiguing resistance exercise: A secondary analysis. J Strength Cond Res 38(6): 1149-1156, 2024-During sustained or repeated maximal voluntary efforts, muscle fatigue (acute strength loss) is not linear. After a large initial decrease, muscle strength plateaus at approximately 40% of baseline. This plateau, which likely reflects muscle strength preservation, has been observed in sustained maximal isometric and repeated maximal isokinetic contractions. Whether this pattern of fatigue occurs with traditional resistance exercise repetitions with free weights and weight stack machines has not been overviewed. Here, the aim was to determine whether the number of repetitions completed across 4 or more consecutive repetitions-to-failure tests exhibits the same nonlinear pattern of muscle fatigue. A secondary analysis was applied to data extracted as part of a recent meta-analysis on repetitions-to-failure tests. Studies were eligible if they reported mean number of repetitions completed in 4-6 consecutive repetitions-to-failure tests at a given relative load. Twenty-nine studies were included. Overall, the results show that the number of repetitions completed in consecutive repetitions-to-failure tests at a given load generally decreases curvilinearly. The numbers of repetitions completed in sets 2, 3, 4, 5, and 6 were equal to approximately 70, 55, 50, 45, and 45% of the number of repetitions completed in set 1, respectively. Longer interset rest intervals typically attenuated repetition loss, but the curvilinear pattern remained. From the results, a chart was created to predict the number of repetitions across 6 sets of resistance exercise taken to failure based on the number of repetitions completed in set 1. The chart is a general guide and educational tool. It should be used cautiously. More data from a variety of exercises, relative loads, and interset rest intervals are needed for more precise estimates of number of repetitions completed during repeated sets of fatiguing resistance exercise.

Impact of squat set configuration on mechanical performance in paired sets of upper-body exercises.

Paired sets and alternative set configurations (e.g., cluster sets) are frequently employed by strength and conditioning practitioners; however, their synergistic impact remains underexplored in research. This study aimed to elucidate whether the set configuration used in a lower-body exercise affects mechanical performance during paired sets of upper-body exercises. Twenty-one resistance-trained individuals (14 men and 7 women) randomly completed three experimental sessions that involved four sets of five repetitions at 75%1RM during both the bench press and bench pull exercises. The three experimental sessions varied solely in the activity conducted during the inter-set rest periods of each upper-body exercise: (i) Traditional squat - six squat repetitions without intra-set rest at 65%1RM; (ii) Rest redistribution squat - two clusters of three repetitions of the squat exercise at 65%1RM with 30s of intra-set rest; and (iii) Passive rest - no exercise. The rest redistribution set configuration allowed the sets of the squat exercise to be performed at a faster velocity than the traditional set configuration (p = 0.037). However, none of the mechanical variables differed between the exercise protocols neither in the bench press (p ranged from 0.279 to 0.875) nor in the bench pull (p ranged from 0.166 to 0.478). Although rest redistribution is an effective strategy to alleviate fatigue during the sets in which it is implemented, it does not allow subjects to perform better in subsequent sets of the training session.

Blood Flow Restriction Training for Meniscus Repair Surgery

Background: Blood flow restriction (BFR) is a training tool that involves wearing a tourniquet or occlusive device during exercise. Data support that low-load training with BFR may produce muscle hypertrophy similar to standard high-load training. Because of the weight-bearing and range of motion (ROM) restrictions after meniscal repair, patients encounter substantial atrophy of lower extremity musculature. We perform BFR for these patients to limit atrophy postoperatively with the goal of facilitating their return to prior function and sports. Indications: We incorporate BFR in the postoperative rehabilitation protocol for patients undergoing meniscal repair not involving the root. Patients with the following are excluded: acute or severe cardiac disease, peripheral vascular disease, blood pressure over systolic 180 mm Hg or diastolic 100 mm Hg, hemophilia, thrombophlebitis or history of deep vein thrombosis, severe anemia, and sickle cell disease. Technique Description: An automated BFR device calculates the patient’s limb occlusion pressure (LOP) and titrates to 50% to 80% of LOP for lower extremity exercises. Exercise parameters typically consist of 4 sets of each exercise, totaling 75 repetitions, with 30-second interset rest. Patients undergo a standard 3-phase postoperative rehabilitation protocol. Phase I (weeks 0-6): Patients are nonweightbearing, may be either footflat weightbearing or partial weightbearing at the surgeon’s, with ROM restricted 0 to 90 in a hinge knee brace throughout the phase. Exercises include quadriceps sets with neuromuscular electrical stimulation and straight leg raises and short/long arcs quadriceps. Phase II (weeks 7-8): Patients progress to weightbearing and ROM as tolerated and begin exercises including double mini squats, hamstring curls, double leg press, and double leg heel raises. Phase III: (weeks 9+): Patients perform double and single leg bridges, double leg bridges on ball with knee band, squats, single leg press, and single leg heel raises, all with the goal of returning to sports. Results: Prior systematic review data demonstrate low-load training with BFR increases muscle strength and induces hypertrophy relative to low-load training alone. No significant differences for Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales between BFR training group and control group. Discussion: BFR training may facilitate postoperative recovery in patients undergoing meniscal repair surgery by helping mitigate muscular atrophy. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Relationship between perceptual and mechanical markers of fatigue during bench press and bench pull exercises: impact of inter-set rest period length.

This study aimed to explore whether the relationship between perceptual (rating of perceived exertion; RPE) and mechanical (maximal number of repetitions completed [MNR], fastest set velocity, and mean velocity decline) variables is affected by the length of inter-set rest periods during resistance training sets not leading to failure. Twenty-three physically active individuals (15 men and eight women) randomly completed 12 testing sessions resulting from the combination of two exercises (bench press and bench pull), three inter-set rest protocols (1, 3, and 5 min), and two minimal velocity thresholds (farther from muscular failure [MVT0.45 for bench press and MVT0.65 for bench pull] and closer to muscular failure [MVT0.35 for bench press and MVT0.55 for bench pull]). The duration of inter-set rest periods did not have a significant impact on RPE values (p ranged from 0.061 to 0.951). Higher proximities to failure, indicated by lower MVTs, were associated with increased RPE values (p < 0.05 in 19 out of 24 comparisons). Moreover, as the number of sets increased, an upward trend in RPE values was observed (p < 0.05 in seven out of 12 comparisons). Finally, while acknowledging some inconsistencies, it was generally observed that higher magnitudes of the mechanical variables, especially MNR (rs < -0.55 in three out of four comparisons), were associated with lower RPE values. These results, which were comparable for the bench press and bench pull exercises, suggest that post-set RPE values are affected by the fatigue experienced at both the beginning and end of the set.

Effects of short and long inter-set rest on maximal isokinetic strength at slow and fast angular velocities in trained young males after eight weeks of resistance training

Resistance training is a widely used method to enhance muscle strength, with acute program variables influencing muscle adaptations. This study focused on the often-neglected variable of inter-set rest interval duration and its impact on muscle strength gains. Existing literature presents conflicting findings, with some studies advocating for longer rest intervals, while the others show comparable strength increases with shorter rests. Methodological differences in prescription and sample groups contributed to these inconsistencies. This study investigated the effect of short and long inter-set rests on maximal isokinetic strength gains of the upper and lower extremities during slow and fast angular velocities after eight weeks of resistance training. The research involved 26 healthy strength-trained males (age=20±1 year, body mass=81.5±8.8 kg, body height=184.4±6.1 cm) randomly assigned to G1m (1-minute rest) or G3m (3-minute rest). The resistance training programs were matched for all acute program variables, emphasizing the rest interval as the primary difference. Isokinetic dynamometry pre- and post-training assessed knee and elbow extensor and flexor maximal strength at 60º/s and 120º/s. The training program consisted of seven exercises performed at 70% 1RM until muscle failure three times per week over eight weeks. The most important result was that G3m, in contrast to G1m, led to a higher increase in peak torque of the knee (p=.037) and elbow extensors (p=.007) as well as the elbow flexors (p=.045) at 60º/s. Furthermore, G3m and G1m similarly increased the peak torque of the knee and elbow extensors and flexors at 120º/s and of the knee flexors at 60º/s (p&amp;gt;.138). In conclusion, the study suggests that strength training with longer inter-set rest intervals may lead to similar strength gains as strength training with shorter inter-set rest intervals. Nonetheless, individuals who prioritize maximizing their strength gains are advised to utilize longer rest intervals. However, shorter rest intervals may still yield significant strength enhancements, particularly for those who are limited by time.

Four Sessions of Repeated-Sprint Cycling Training With or Without Severe Hypoxia Do Not Modify Overground Running Sprint Force-Velocity Profile.

To investigate the effect of cycling-based repeated-sprint training in hypoxia versus in normoxia on single overground running sprint performance and associated force-velocity (F-V) profile in world-class female rugby sevens players. Eighteen world-class female rugby sevens players were randomly assigned to repeated-sprint cycling training in normobaric hypoxia (n = 9) or normoxia (n = 9) groups. Training consisted of 4 sessions ofrepeated-sprint cycling training in normobaric hypoxiaor in normoxia (4 × 5 × 5-s cycle sprints-25-s intersprint recovery performed in simulated altitude of ∼5000m or in normoxia with 3-min interset rest in normoxia for both groups) in addition to rugby sevens training and strength and conditioning sessions within a 9-day intervention period before an international competition. Before and 1day after the intervention, single 50-m overground running "all-out" sprint performance and associated F-V-related mechanical output were assessed. No interaction (group × time; all P > .088), time effect(before vs 1d after; all P > .296), or group effect(repeated-sprint cycling training in normobaric hypoxia vs in normoxia; all P > .325) was detected for 50-m overground running sprint performance and any derived F-V profiling variables. Four sessions ofrepeated-sprint training either in hypoxia or in normoxia performed over 9days had no influence on single 50-m overground running sprint performance and associated F-V profile. In world-class female rugby sevens players, the intervention (training camp before an international competition) might have been too short to induce measurable changes. It is also plausible that implementing a similar program in players with likely different F-V profile may result in negligible mechanical effect.

Reliability of Three Landmine-Punch-Throw Variations and Their Load-Velocity Relationships Performed With the Dominant and Nondominant Hands.

This study assessed the reliability and load-velocity profiles of 3 different landmine-punch-throw variations (seated without trunk rotation, seated with trunk rotation, and standing whole body) with different loads (20, 22.5, and 25.0kg), all with the dominant hand and nondominant hand. In a quasi-randomized order, 14 boxers (24.1 [4.3]y, 72.6 [10.1]kg) performed 3 repetitions of each variation with their dominant hand and theirnondominant hand, with maximal effort and 3minutes of interset rest. Peak velocity was measured via the GymAware Power Tool (Kinetic Performance Technologies). The interclass correlation coefficients and their 95% CIs were used to determine the intrasession reliability of each variation × load × hand combination. Additionally, a 2 (hand) × 3 (variation) repeated-measures analysis of variance assessed the load-velocity profile slope, and a 3 (variation) × 2 (hand) × 3 (load) repeated-measures analysis of variance assessed the peak velocity of each variation. Most variations were highly reliable (intraclass correlation coefficient > .91), with the nondominant hand being as reliable or more reliable than the dominant hand. Very strong linear relationships were observed for the group average for each variation (R2 ≥ .96). However, there was no variation × hand interaction for the slope, and there was no main effect for variation or hand. Additionally, there was no interaction for the peak velocity, but there were main effects for variation, hand, and load (P < .01). Each variation was reliable and can be used to create upper-body ballistic unilateral load-velocity profiles. However, as with other research onload-velocity profile, individual data allowed for more accurate profiling than group average data.

Effect of Blood Flow Restriction during the Rest Periods of Squats on Accuracy of Estimated Repetitions to Failure.

This study investigated the impact of resistance training with blood flow restriction during rest (BFRrest) on the accuracy of estimated repetitions to failure (ERF). It also explored associations between error in ERF and mean concentric velocity (MCV) along with physiological responses. In a randomised cross-over study, 18 male trainers (23.4 ± 2.7 years) performed three sets of squats at 70% of their one-repetition maximum until failure. One session integrated BFRrest, while another employed traditional passive inter-set rest (TRAD) during the 3 min inter-set rest intervals. Cardiorespiratory and metabolic measures were taken in the inter-set recovery periods. The results revealed no significant differences between BFRrest and TRAD in terms of ERF and error in ERF. A notable set effect for ERF was observed, with a greater ERF during set 1 compared to sets 2 and 3 (p < 0.001). Additionally, a lower error in ERF was observed during sets 2 and 3 compared to set 1 (p < 0.001). Error in ERF were strongly associated with the respiratory exchange ratio, and moderately associated with end-tidal carbon dioxide partial pressure, carbon dioxide output, and MCV variables. Notably, the precision of ERF seems to be predominantly influenced by indicators of physiological stress rather than the incorporation of BFRrest.

Optimizing mechanical performance in the bench press: The combined influence of inter-set rest periods and proximity to failure

ABSTRACT This study examined the influence of inter-set rest periods of 1 (R1), 3 (R3) and 5 (R5) minutes on the number of repetitions completed before exceeding the minimum velocity thresholds of 0.45 m⋅s−1 (MVT0.45) and 0.35 m⋅s−1 (MVT0.35) during the bench press exercise. Twenty-three physically active individuals, 15 men and eight women, randomly completed six testing sessions consisting of four sets of the bench press exercise performed with maximal intent against 75% of the one-repetition maximum. Testing sessions differed in the length of inter-set rest periods (R1, R3, and R5) and MVT applied (MVT0.45 and MVT0.35). The number of repetitions was lower using shorter inter-set rest periods (R1 < R3 < R5), but R3 was more similar to R1 and R5 using MVT0.45 and MVT0.35, respectively. The fastest velocity of the set was reduced with the increment in the number of sets for the three protocols using MVT0.35 (greater reduction for shorter rest periods), but it was only reduced for R1 when using MVT0.45. The results suggest that, to maintain bench press mechanical performance, 5-min inter-set rest periods are necessary when sets are terminated close to failure (MVT0.35), while 3 min may suffice when sets are terminated farther from failure (MVT0.45).

Effect of resistance training programs differing in set structure on muscular hypertrophy and performance in untrained young men.

Purpose: This study aimed to compare the effects on muscle hypertrophy and muscular performance of two resistance training (RT) programs that differed only in set structure: traditional set structure (TS) vs. rest redistribution set structure (RR). Methods: Thirty untrained young men were pair-matched and randomly assigned to a TS (n = 15) or an RR (n = 15) protocol based on individual baseline measures. Participants trained for 8weeks using the same total body RT routines performed twice weekly. The TS protocol comprised four sets of 10 repetitions per exercise with 120-s interset rest, and the RR involved eight sets of five repetitions per exercise with 51-s interset rest. Participants were tested pre- and post-intervention for body composition, regional muscle thickness, upper- and lower-body muscle maximal strength [1-repetition maximum (1RM)], mean power output and velocity at 75% 1RM and muscular endurance (repetitions to failure at 70% 1RM). Results: Compared to baseline, both groups exhibited equally significantly decreased body fat mass (p < 0.05), increased fat-free mass (p < 0.001), muscle thickness (p < 0.05), upper and lower-body muscular maximal strength (p < 0.001) and endurance performance (p < 0.001). However, both groups only increase the lower-body power output (p < 0.001) but not the upper-body (p > 0.05). No significant differences existed between groups for all measurements (p > 0.05). Conclusion: These results suggest that RR and TS groups have similar effects for improving muscle hypertrophy and performance in untrained young men.

Interference Effects of Different Resistance-Training Protocols on Rowing Ergometer Performance: A Study on Semiprofessional Rowers.

To evaluate the interference effects of various resistance-training (RT) protocols on rowing ergometer performance. Fourteen semiprofessional male rowers randomly completed 5 protocols in separate sessions: (1)control-no RT session was performed, (2)upper-body high-fatigue-4 sets to failure during the bench pull exercise, (3)upper-body low-fatigue-4 sets of 6 repetitions during the bench pull exercise, (4)lower-body high-fatigue-4 sets to failure during the leg-press exercise, and (5)lower-body low-fatigue-4 sets of 6 repetitions during the leg-press exercise. All sets were performed against the 12-repetition-maximum load with 2minutes of interset rest. Following the completion of the protocols, subjects performed an all-out 1000-m rowing ergometer test. Compared with the control condition, rowing ergometer performance was not significantly affected after the low-fatigue RT protocols (upper body: P ≥ .487; Δ = 0.0%-0.2%; lower body: P ≥ .200; Δ = -0.2%-0.5%), while it significantly declined following high-fatigue RT protocols (upper body: P ≤ .001; Δ = 1.0%-2.0%; lower body: P ≤ .002; Δ = 2.1%-2.5%). The average heart rate was significantly lower for the control condition compared with all RT protocols (P ≤ .043; Δ = 1.0%-1.5%). To minimize interference on rowing performance, coaches should prioritize the level of effort in RT protocols over specific exercises, specifically avoiding high-fatigue protocols that lead to failure before rowing practice.

Manipulating Internal and External Loads During Repeated Cycling Sprints: A Comparison of Continuous and Intermittent Blood Flow Restriction.

Mckee, JR, Girard, O, Peiffer, JJ, and Scott, BR. Manipulating internal and external loads during repeated cycling sprints: A comparison of continuous and intermittent blood flow restriction. J Strength Cond Res XX(X): 000-000, 2023-This study examined the impact of blood flow restriction (BFR) application method (continuous vs. intermittent) during repeated-sprint exercise (RSE) on performance, physiological, and perceptual responses. Twelve adult male semi-professional Australian football players completed 4 RSE sessions (3 × [5 × 5-second maximal sprints:25-second passive recovery], 3-minute rest between the sets) with BFR applied continuously (C-BFR; excluding interset rest periods), intermittently during only sprints (I-BFRWORK), or intraset rest periods (I-BFRREST) or not at all (Non-BFR). An alpha level of p < 0.05 was used to determine significance. Mean power output was greater for Non-BFR ( p < 0.001, dz = 1.58 ), I-BFRWORK ( p = 0.002, dz = 0.63 ), and I-BFRREST ( p = 0.003, dz = 0.69 ) than for C-BFR and for Non-BFR ( p = 0.043, dz = 0.55 ) compared with I-BFRREST. Blood lactate concentration ( p = 0.166) did not differ between the conditions. Mean oxygen consumption was higher during Non-BFR ( p < 0.001, dz = 1.29 and 2.31; respectively) and I-BFRWORK (p < 0.001, dz = 0.74 and 1.63; respectively) than during I-BFRREST and C-BFR and for I-BFRREST ( p = 0.002, dz = 0.57) compared with C-BFR. Ratings of perceived exertion were greater for I-BFRREST ( p = 0.042, dz = 0.51) and C-BFR ( p = 0.011, dz = 0.90) than for Non-BFR and during C-BFR ( p = 0.023, dz = 0.54) compared with I-BFRWORK. Applying C-BFR or I-BFRREST reduced mechanical output and cardiorespiratory demands of RSE and were perceived as more difficult. Practitioners should be aware that BFR application method influences internal and external demands during RSE.

The intensity of a resistance exercise session can be quantified by the work rate of exercise.

Athletes regularly perform resistance training, yet it is unknown how best to monitor its intensity. This study compared different resistance exercise intensity metrics to determine their sensitivity to manipulating work rate (via altering inter-set rest and load). Following baseline testing for 10- and 3-repetition maximum (RM; squat and bench press), fourteen trained participants completed four volume-matched protocols in a randomised order: 3x10 with 85% 10RM, 60 s rest (3x1060s); 3x10 with 85% 10RM, 180 s (3x10180s); 8x3 with 85% 3RM, 120 s (8x3120s); 8x3 with 85% 3RM, 300 s (8x3300s). Internal intensity was quantified via rate of oxygen consumption ([Formula: see text]), heart rate, blood lactate concentration, and rating of perceived exertion (RPE). External intensity was assessed via previously developed "Training-Intensity" (TI) and "Intensity-Index" (II) metrics, and from exercise work rate (expressed as kg∙min-1 and joules∙min-1). Internal intensity and work-rate metrics were highest for 3x1060s, followed by 3x10180s, 8x3120s and 8x3300s (p≤0.027). TI and II were higher for 8x3 than 3x10 protocols (p<0.001), but not different within these configurations. Internal intensity measures were more strongly correlated with work rate (r = 0.37-0.96) than TI and II (r = -0.42-0.33) metrics. Work rate corroborated objective internal intensity metrics during resistance exercise, with the highest work rate session (3x1060s) also eliciting greater RPE scores than other protocols. In contrast, the TI and II did not agree with other intensity measures, likely because they do not consider rest periods. Practitioners can plan for the physiological and perceptual demands of resistance training by estimating work rate.