Sets Of Resistance Exercise Research Articles

The Influence of Mental Fatigue on Physical Performance and Its Relationship with Rating Perceived Effort and Enjoyment in Older Adults

ABSTRACT The study investigated the influence of mental fatigue on older people’s enjoyment during a series of physical exercises. Using a randomized cross-over design, participants (n = 35) completed a 6-minute walking test − 6MWT, a Timed Up and Go—TUG test and three sets of knee extension exercise (first set: KE1, second set: KE2, third set: KE3) under two experimental conditions (control or mental fatigue). The Nonparametric Analysis of Longitudinal Data in Factorial Experiments was used to compare the number of repetitions performed during three sets of resistance exercise between conditions. The same analysis method was applied to compare the perception of effort and enjoyment across five moments (Post-6MWT, Post-TUG, Post-KE1, Post-KE2, Post-KE3) and two conditions and the Visual Analogue Scales (VAS) across four moments (baseline, Pre-6MWT, Pre-TUG, Pre-KE) and two conditions. Mental fatigue did not affect the physical function, perception of effort and enjoyment of exercise in older people. Participants, however, reported higher enjoyment for walking and dynamic balance compared to strength exercise. Mental fatigue had no effect on the physical function, perception of effort and enjoyment of exercise of older people. Participants presented a higher enjoyment for walking and dynamic balance compared to strength exercise. Given the importance of resistance exercises for health, clinicians should prioritize resources to education programs emphasizing the benefits of resistance exercise in both short- and long-term health. Including social interaction opportunities in physical exercise programs and prescribing activities appropriate to participants’ ability levels could enhance engagement and adherence.

Muscle Oxygen Saturation Dynamics During Upper-Body Resistance Exercise

Research examining the changes in muscle oxygen saturation across multiple sets of resistance exercise is limited. The purpose of this study was to describe the physiological response of muscle oxygenation parameters during upper-body resistance exercise and examine the differential effects of relevant participant characteristics on resistance training performance and muscle oxygen saturation dynamics. Sixty-one recreationally trained men (n = 44; 21.8 ± 2.6 years) and women (n = 17; 20.2 ± 1.8 years) completed five-repetition maximum sets of barbell bench presses at a load equal to 75% 1-RM with a 2 min rest interval. Muscle oxygen saturation (SmO2) dynamics within the anterior deltoid were monitored using a portable near-infrared spectroscopy sensor. The percent change in SmO2 (∆%SmO2), the muscle oxygen re-saturation rate (SmO2RecSlope), and the highest measured SmO2 value during recovery periods (SmO2Peak) were measured. Two-way (sex [men, women] x time [sets 1–5]) repeated measures analyses of variance (ANOVA) were performed on muscle saturation variables. To examine the effect of relevant controlling variables, separate analyses of covariance (ANCOVA) with repeated measures were also performed. No differences were seen with ∆%SmO2 across sets. The main effects for sets occurred for SmO2RecSlope, whereby a decline was noted on sets 4 and 5 (p = 0.001) compared to set 1. Additionally, SmO2Peak was the lowest on set 5 (p < 0.001) compared to all other sets. Moreover, body mass (p = 0.013), diastolic blood pressure (p = 0.044), and mean arterial pressure (p = 0.033) for ∆%SmO2 were the only significant covariates noted amongst the muscle oxygenation variables. In conclusion, no sex differences and only a few set differences in muscle oxygen saturation dynamics were seen without employing any covariates. Body mass, diastolic blood pressure, and mean arterial pressure were identified as factors that could influence observed responses.

Increased Neuromuscular Activity, Force Output, and Resistance Exercise Volume When Using 5-Minute Compared with 2-Minute Rest Intervals Between the Sets.

McMahon, G, Best, N, Coulter, T, and Erskine, RM. Increased neuromuscular activation, force output and resistance exercise volume when using 5-minute compared with 2-minute rest intervals between the sets. J Strength Cond Res 38(9): 1527-1534, 2024-Longer rest intervals between resistance exercise (RE) sets may promote greater muscle hypertrophy and strength gains over time by facilitating the completion of greater training volume and intensity. However, little is known about the acute neuromuscular responses to RE sets incorporating longer vs. shorter rest intervals. Using a within-subject, crossover design, 8 healthy, young subjects completed 2 separate acute bouts of 4 sets of 8 × 3-s maximal isometric contractions using either a 2-minute (REST-2) or 5-minute (REST-5) rest interval between sets. Peak torque (PT) and electromyography (EMG) were measured pre and 5 minutes postexercise. Peak torque and mean torque (MT), EMG, mean, and median frequencies were measured during each set, whereas blood lactate (BLa), heart rate (HR), and rating of perceived exertion (RPE) were measured following each set. Peak torque and MT were lower ( p < 0.05) in sets 3 and 4, and sets 2-4 in REST-2 compared with REST-5, respectively. Electromyography and BL were lower and higher, respectively, in REST-2 vs. REST-5. There was no main effect of condition on HR or RPE. Pre-to-post exercise reductions in PT (-17 ± 9% vs. -4 ± 7%) and EMG (-29 ± 14% vs. -10 ± 7%) were greater ( p < 0.001) in REST-2 vs. REST-5. Total exercise volume was less in REST-2 vs. REST-5 (9,748 ± 2296 N·m -1 vs. 11,212 ± 2513 N·m -1 , p < 0.001). These results suggest that incorporating 5-minute between-set rest intervals into a resistance exercise session facilitates improved neuromuscular function, increased exercise volume, and less metabolic stress compared with 2-minute rest intervals. Thus, 5-minute rest intervals may be more efficacious for promoting muscle hypertrophy and strength gains in a chronic resistance training program.

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.

Effects of external limb compression and/or low‐load resistance exercise on post‐activation performance enhancement during countermovement jumps

AbstractThe effects of low‐load resistance exercise combined with external limb compression (ELC) to augment post‐activation performance enhancement during countermovement jumps have yet to be examined. We assessed the separate and combined effects of ELC and sets of low‐load (back squats) resistance exercise (both compared with controls) during conditioning routines, and determine their subsequent neuromechanical consequences during countermovement jumps. On separate days, twenty strength‐trained men completed a familiarization session followed by four experimental trials in a randomized design that included one of the following conditioning routines: passive rest (Control [CON], no occlusion/standing), exercise (sets of low‐intensity resistance exercise [RE] with 30% 1RM, no occlusion/exercise), ELC ([ELC] at 80% of the individual arterial occlusion pressure, occlusion/standing), and combined ELC and exercise ([ELC + RE], occlusion/exercise). Countermovement jump performance (jump height, relative peak power output, vertical impulse, and rate of force development) was assessed at baseline, immediately after, and at the third, sixth, ninth and twelfth minute following each conditioning routine. Compared to baseline, jump height, relative peak power output and vertical impulse values were lower at 0 min for [RE] (−3.5%–8.2%; p ≤ 0.014) and higher at +3 min for [ELC] (+2.0%–3.8%; p ≤ 0.013). Regarding [ELC + RE], values for these three variables were lower at 0 min (−4.8%–8.0%; p &lt; 0.001) but higher at +12 min (+2.9%–5.5%; p &lt; 0.001) versus baseline. In strength‐trained men, using ELC either alone (while standing) or combined with low‐load resistance exercise sets (during back squats) can be a useful way to improve CMJ mechanics. However, the duration and magnitude of post‐activation potentiation performance benefits varied depending on the type of ELC protocol used.

Endocannabinoid and psychological responses to acute resistance exercise in trained and untrained adults.

This study examined the effects of acute resistance exercise on circulating endocannabinoid (eCB) and mood responses in trained and untrained healthy adults. Thirty-two healthy adults (22.1 ± 2.9 years) were recruited from trained (reporting resistance exercise at least twice per week for ≥ previous three months) and untrained (performing no resistance exercise for ≥ previous three months) groups. Participants (13 male, 19 female) completed three sets of resistance exercise (16 repetitions at 50% 1-repetition max, 12 repetitions at 70% 1-repetition max, 8 repetitions at 80% 1-repetition max). Resistance machines targeted the legs, chest, back, and abdominal muscles. Mood states, affect, and circulating eCB concentrations were evaluated before and after resistance exercise. There were significant decreases in AEA, PEA, and OEA levels following acute resistance exercise (p <0.05; ds = -0.39, -0.48, -0.65, respectively), with no significant group differences or group by time interactions. 2-AG did not change significantly. Positive affect increased significantly following resistance exercise (p = 0.009), while negative affect decreased (p <0.001). Depressive symptoms, anger, confusion, and total mood disturbance decreased significantly (p <0.05), while vigor increased significantly following resistance exercise (p = 0.005). There were no significant group differences or group by time interactions for any psychological outcomes. These results indicate that acute resistance exercise may reduce eCB and related lipid concentrations, which is opposite to the increase in lipids typically observed with acute aerobic exercise. Furthermore, psychological improvements occur after resistance exercise regardless of decreases in eCBs, supporting the notion that psychological changes with exercise likely occur through a wide variety of biological and environmental mechanisms.

The Importance of Previous Resistance Training Volume on Muscle Growth in Trained Individuals

ABSTRACT Resistance training volume has been suggested to be one of the most effective variables for developing muscular hypertrophy. Meta-analyses have concluded that there exists a dose-response relationship between weekly resistance training volume (i.e., the number of sets performed over the training week) and muscle mass accrual in nonresistance-trained individuals; however, experimental data in resistance-trained individuals have shown conflicting results. Current literature suggests that the performance of additional sets of resistance exercise within a single training session and training week does not inherently result in greater increases in muscle size compared with groups or conditions that perform lower volumes of resistance training. Notwithstanding these results, it has been suggested that controlling for each individual's previous training volume could improve the precision of the muscle hypertrophic response to resistance training and that failing to do so would disregard the principle of progressive overload. Herein, we explore the evidence for the suggestion that a higher-volume approach to training, in comparison to what an individual has been accustomed to, would improve the precision of the muscle growth response to resistance training and the physiological rationale that may (or may not) underpin this phenomenon.

Respiratory aerosol particle emission and simulated infection risk is greater during indoor endurance than resistance exercise

Pathogens such as severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), influenza, and rhinoviruses are transmitted by airborne aerosol respiratory particles that are exhaled by infectious subjects. We have previously reported that the emission of aerosol particles increases on average 132-fold from rest to maximal endurance exercise. The aims of this study are to first measure aerosol particle emission during an isokinetic resistance exercise at 80% of the maximal voluntary contraction until exhaustion, second to compare aerosol particle emission during a typical spinning class session versus a three-set resistance training session. Finally, we then used this data to calculate the risk of infection during endurance and resistance exercise sessions with different mitigation strategies. During a set of isokinetic resistance exercise, aerosol particle emission increased 10-fold from 5,400 ± 1,200 particles/min at rest to 59,000 ± 69,900 particles/min during a set of resistance exercise. We found that aerosol particle emission per minute is on average 4.9-times lower during a resistance training session than during a spinning class. Using this data, we determined that the simulated infection risk increase during an endurance exercise session was sixfold higher than during a resistance exercise session when assuming one infected participant in the class. Collectively, this data helps to select mitigation measures for indoor resistance and endurance exercise classes at times where the risk of aerosol-transmitted infectious disease with severe outcomes is high.

Can mixed circuit training elicit the recommended exercise intensity and energy expenditure in people after stroke?

ABSTRACT Purpose To investigate whether mixed circuit training (MCT) elicits the recommended exercise intensity and energy expenditure in people after stroke, and to establish the between-day reproducibility for the percentages of heart rate reserve (%HRR), oxygen uptake reserve (%VO2R), and energy expenditure elicited during two bouts of MCT. Methods Seven people aged 58 (12) yr, who previously had a stroke, performed a cardiopulmonary exercise test, a non-exercise control session, and two bouts of MCT. The MCT included 3 circuits of 10 resistance exercises at 15-repetition maximum intensity, with each set of resistance exercise interspersed with 45-s of walking. Expired gases were collected during the MCT and control session and for 40 min afterward. Control session was necessary to calculate the net energy expenditure associated with each bout of MCT. Results Mean %VO2R (1st MCT: 51.1%, P = .037; 2nd MCT: 54.0%, P = .009) and %HRR (1st MCT: 66.4%, P = .007; 2nd MCT: 67.9%, P = .010) exceeded the recommended minimum intensity of 40%. Both %VO2R (P = .586 and 0.987, respectively) and %HRR (P = .681 and 0.237, respectively) during the 1st and 2nd bouts of MCT were not significantly different to their corresponding gas exchange threshold values derived from cardiopulmonary exercise testing. Mean net total energy expenditure significantly exceeded the minimum recommend energy expenditure in the 1st (P = .048) and 2nd (P = .023) bouts of MCT. Between-day reproducibility for %HRR, %VO2R, and energy expenditure was excellent (ICC: 0.92–0.97). Conclusions MCT elicited physiological strain recommended for improving health-related fitness in people after stroke and these responses demonstrated excellent between-day reproducibility.

Acute cardiovascular responses to unilateral bicep curls with blood flow restriction

Background/ObjectivesA consensus on the acute cardiovascular responses to low intensity (LI) resistance exercise (RE) combined with blood flow restriction (BFR) has not yet been reached. This study was designed to compare acute cardiovascular responses to a single bout of LIRE, high intensity (HI) RE, and LIRE with BFR in physically active young males. MethodsParticipants completed 3 RE sessions in random order, where each session consists of 4 sets of unilateral dumbbell bicep curls. Cardiovascular hemodynamics were measured at baseline and right after each set of RE. ResultsAortic augmentation index (AIx) was significantly higher after set 2,3,4 of RE in LI + BFR session compared to LI session (P < 0.05). Brachial systolic blood pressure (SBP), heart rate (HR), brachial rate pressure product (RPP), and central RPP responses did not differ between LI and LI + BFR sessions (P > 0.05). HI session had a higher central SBP, brachial RPP, central RPP, and aortic AIx compared to LI session after each set of RE (P < 0.05), but not brachial SBP (P > 0.05). ConclusionsTaken together, this study showed that LIRE combined with BFR acutely augmented aortic stiffness, as also observed in HI session, but myocardial oxygen consumption was only higher in HI session when compared to LI session. Thus, although BFR did not exaggerate cardiovascular responses nor cause extra myocardial oxygen consumption, it should be prescribed with caution when control of acute aortic stiffening is necessary during RE.

Maximizing Strength: The Stimuli and Mediators of Strength Gains and Their Application to Training and Rehabilitation.

Spiering, BA, Clark, BC, Schoenfeld, BJ, Foulis, SA, and Pasiakos, SM. Maximizing strength: the stimuli and mediators of strength gains and their application to training and rehabilitation. J Strength Cond Res 37(4): 919-929, 2023-Traditional heavy resistance exercise (RE) training increases maximal strength, a valuable adaptation in many situations. That stated, some populations seek new opportunities for pushing the upper limits of strength gains (e.g., athletes and military personnel). Alternatively, other populations strive to increase or maintain strength but cannot perform heavy RE (e.g., during at-home exercise, during deployment, or after injury or illness). Therefore, the purpose of this narrative review is to (a) identify the known stimuli that trigger gains in strength; (b) identify the known factors that mediate the long-term effectiveness of these stimuli; (c) discuss (and in some cases, speculate on) potential opportunities for maximizing strength gains beyond current limits; and (d) discuss practical applications for increasing or maintaining strength when traditional heavy RE cannot be performed. First, by conceptually deconstructing traditional heavy RE, we identify that strength gains are stimulated through a sequence of events, namely: giving maximal mental effort, leading to maximal neural activation of muscle to produce forceful contractions, involving lifting and lowering movements, training through a full range of motion, and (potentially) inducing muscular metabolic stress. Second, we identify factors that mediate the long-term effectiveness of these RE stimuli, namely: optimizing the dose of RE within a session, beginning each set of RE in a minimally fatigued state, optimizing recovery between training sessions, and (potentially) periodizing the training stimulus over time. Equipped with these insights, we identify potential opportunities for further maximizing strength gains. Finally, we identify opportunities for increasing or maintaining strength when traditional heavy RE cannot be performed.

EFFECT OF SINGLE AND MULTIPLE SESSIONS OF SELF-MYOFASCIAL RELEASE: SYSTEMATIC REVIEW

ABSTRACT Self-myofascial release with a roller has been used as a tool to accelerate recovery. The objective of this systematic review was to investigate how one session or multiple sessions of self-myofascial release with a roller affect the recovery of an athlete´s performance. The research was conducted in the PubMed, Scopus, Cochrane Library, BVS, Embase, SPORTDiscus, ScienceDirect, and Google Scholar databases using the terms: foam rolling, foam roller, and self-myofascial release combined with recovery, exercise, fatigue, and sport and acute effects, chronic effects and performance, resulting in 12,020 articles. After checking the inclusion criteria, 40 studies were selected and analyzed. It was concluded that multiple sessions of self-myofascial release with a roller are more effective in recovering lower limb power and speed performance than just one session. A single session is more effective for recovering strength performance than multiple sessions. Moreover, both single and multiple sessions showed similar results in the recovery of agility, pain, flexibility, blood lactate removal, and perception of recovery. Finally, multiple sessions between sets of resistance exercise seem to reduce performance, decreasing the number of repetitions and resistance to fatigue, while a single session did not produce a significant effect. Self-myofascial release with a roller demonstrates potential for speeding up the recovery process of athletes. Future studies should evaluate the effect of the regular use of self-myofascial release with a roller on performance recovery. Level of evidence II; Systematic review.

The Effect of Resistance Training With Electrical Muscle Stimulation on Atrogin-1 and Muscle Ring Finger-1 in Elite Male Athletes After Anterior Cruciate Ligament Surgery

Background and Aims The cellular mechanisms preventing muscle atrophy after Anterior Cruciate Ligament (ACL) regeneration are not well understood. The aim of the present study was to evaluate the effect of resistance training combined with electrical muscle stimulation on serum levels of atrogin-1 and muscle RING finger-1 (MuRF1) in elite athletes following ACL surgery. Methods Among the elite athletes of Razavi Khorasan Province, 20 athletes voluntarily participated in the study and were divided into two groups (ten cases each), including 1) resistance training- electrical muscle stimulation (RT-EMS), and 2) resistance training (RT). The subjects in both groups performed 2-4 sets of resistance exercises (knee extension machine, squat, and knee flexion machines) at an intensity of 30-70% of ten repetitions for 12 weeks. The subjects in the RT-EMS group performed the exercises in combination with electrical stimulation at 35-70 Hz. Blood samples were collected from all subjects before and 48 hours after the last training session to measure atrogin-1 and MuRF1 levels. Analysis of covariance (ANCOVA) and paired t-test were used to compare between- and within-group changes, respectively, and a P&lt;0.05 was considered significant. Results The results showed that 12 weeks of resistance training- electrical muscle stimulation significantly decreased serum levels of atrogin 1 (P=0.013) and MuRF1 (P=0.008) in the post-test compared to the pre-test. In addition, the between-groups comparison showed a significant difference in atrogin 1 levels between the RT-EMS and RT groups (P=0.047). Conclusion It can be suggested that resistance training in combination with electrical muscle stimulation is associated with lower levels of muscular atrophy proteins, such as atrogin-1 and MuRF1, and therefore, can be more effective than resistance training alone.

Hemodynamic during resistance exercise sets and rest intervals in young and older men

Intense blood pressure elevations during resistance exercise (RE) could lead to risk of acute cardiovascular events. Since, the natural aging process contribute to rest and exercise elevations in BP it could be expected higher BP elevations following RE in older individuals. However, the studies have shown contradictory findings which are likely due to the time of BP assessment following exercise. Thus, we compared BP changes after each set and rest interval in young and older men. Sixteen men (8 each group) underwent four sets until fatigue at leg press equipment with high load (80% 1RM). BP was assessed, by finger photoplethysmography and the other cardiovascular measurements were estimated based on body characteristics. Systolic BP (SBP) and mean BP (MBP) increased more in older men at first sets; heart rate (HR) increased more in young during all sets and rest intervals; cardiac output (CO) maintained higher all the time in young; and total peripheral resistance (TPR) increased more during all sets in older men. Thus, the present study shows that RE performed to fatigue leads to higher BP increase in older men suggesting BP might be monitored during RE for safe proposal especially on this higher risk population.

The effects of resistance training in patients with primary Sjogren's syndrome.

Resistance training (RT) is well tolerated and has shown promise for decreasing fatigue. However, the effects of RT have never been examined in primary Sjogren's syndrome (pSS). To assess the feasibility, effectiveness, and safety of a resistance exercise program on fatigue in patients with pSS. This is a parallel, single-blind randomized trial. Women aged 18 years or older, diagnosed with pSS according to the American-European criteria, were included. We randomized 59 participants to a resistance training group (RT) or a control group (CG). Participants in the RT group performed a 16-week resistance exercise program. The sessions consisted of three sets of resistance exercises (10 repetitions each) at 60 to 80% of 1 repetition maximum, designed to improve whole-body strength. The participants in the CG received their usual pharmacological treatment and instructions regarding disease control, pain management, sleep hygiene, and activities of daily living. To compare intergroup and intragroup variability, a one-factor repeated-measures analysis of variance (ANOVA) was used. RT effectively improved fatigue, pain, functional capacity, emotional aspects, vitality, and subjective perception of disease activity by the patient. No between-group differences were found in the ESSPRI mental score, ESSDAI, SF-36-Physical Aspects, SF-36-General Health, SF-36-Social aspects, and SF-36-Mental Health after the training period. An RT program was safe and effective in improving fatigue, pain, functional capacity, emotional aspects, vitality, and subjective perception of disease activity by the patient in women with pSS. Key Points • This is the first study to evaluate the effects of a resistance training program on fatigue in patients with primary Sjogren's syndrome. • A resistance training program was shown to be effective in improving fatigue in patients with primary Sjogren's syndrome. • A resistance training program is well-tolerated, has good compliance, and is not associated with serious adverse effects in patients with primary Sjogren's syndrome.

Acute Effects of Different Rest Intervals Between Sets of Resistance Exercise on Neuromuscular Fatigue in Trained Older Women.

Jambassi Filho, JC, Gurjão, ALD, Prado, AKG, Gallo, LH, and Gobbi, S. Acute effects of different rest intervals between sets of resistance exercise on neuromuscular fatigue in trained older women. J Strength Cond Res 34(8): 2235-2240, 2020-The aim of this study was to investigate the acute effect of different rest intervals (RIs) between sets on total volume, time under tension, maximal voluntary contraction (MVC), and integrated electromyography (iEMG) activity of the vastus lateralis (VL) and vastus medialis (VM) muscles. Twenty-one resistance-trained older women (66.4 ± 4.4 years; 69.1 ± 11.4 kg; 157.5 ± 5.0 cm) completed 3 different test sessions, performed 48-72 hours apart, in a randomized and counterbalanced within-subjects design. In 2 test sessions, the participants performed 3 sets to voluntary exhaustion with loads that corresponded to 15 maximum repetitions, with either 1-minute RI (RI-1) or 3-minute RI (RI-3). In another test session, the participants remained at rest for 15 minutes. The total volume of exercise and time under tension for the RI-3 session was statistically higher (p ≤ 0.05) than the RI-1 session. Postexercise MVC for the RI-3 session showed significantly greater reductions (-7.8%; p ≤ 0.05) compared with the RI-1 and control sessions. No significant changes in postexercise iEMG activity of the VL and VM were shown for any of the sessions (all p > 0.05). The findings of this study suggest that different RIs between sets lead to different acute neuromuscular responses. The longer RI seemed to induce higher neuromuscular fatigue, likely due to higher total volume and time under tension. Thus, longer RI may be a strategy that possibly would lead to greater long-term gains in muscle strength and hypertrophy of the lower limbs in trained older women.

Does the number of sets in a resistance exercise session affect the fast and slow phases of post-exercise cardiac autonomic recovery?

Abstract Aims: The purpose of this study was to evaluate the acute effects of different resistance exercise (RE) volumes on postexercise cardiac autonomic modulation in men. Methods: Ten young men (25.5 ± 4.9 years, 24.8 ± 2.1 kg/m2) performed 3 trials of RE with 1, 2 or 3 sets (48-72 h between each trial) of 10-12 repetitions (70% of the one-maximum repetition) of bench press, leg press, and barbell row. Heart rate variability (HRV) was assessed at the 1st and 5th minutes of recovery (fast phase) and 3 consecutive 5-minute intervals from the 5th to 20th minute of recovery (slow phase). Parasympathetic and global modulations were assessed using the SD1 and SD2 indices of HRV, respectively. The comparison of the interventions was performed using the Friedman and Wilcoxon tests (p<0.05). Results: Lower parasympathetic modulation was identified after 2 and 3 sets compared to 1 set in both the fast and slow recovery phases (p= 0.004-0.05). Lower global modulation was identified after 3 sets compared to 1 set in both fast and slow recovery phases (p= 0.005-0.01). No differences in post-exercise parasympathetic and global modulation were observed between 2 and 3 sets. Conclusion: We concluded that 2 and 3 sets of RE compared to 1 set promoted higher autonomic reduction on the post-exercise phase, which should be considered by coaches when prescribing an RE program for untrained participants or intend to manipulate the postexercise organic recovery.

Genç Yetişkinlerde Setler Arası Dinlenme Aralığı Sürelerinin ve Farklı Yüklerin Kuvvet Egzersizi Serilerindeki Tekrar Sayısına Etkisi

Amaç: Araştırmada, kuvvet antrenman geçmişi olmayan genç yetişkinlerde düşük ve yüksek yükte yapılan kuvvet egzersizinde setler arası dinlenme aralığı sürelerinin tekrar performansına etkileri incelendi. Gereç ve Yöntemler: Araştırmaya, yaş aralığı 18-24 yıl olan, düzenli fiziksel aktivite programlarına katılmayan 12 erkek ve 12 kadın genç yetişkin katıldı. Katılımcıların bench pres ve squat hareketlerinde bir tekrar maksimum kuvvet performansları belirlendi. Farklı günlerde katılımcılara, toplamda 4 set, 1 tekrar maksimum (1TM) kuvvet değerinin %50'sine denk gelen yüklerle her sette 18 tekrar, %80'ine denk gelen yükte her sette 8 tekrar ve setler arasında 1, 3 ve 5 dk dinlenme aralıklarıyla uygulama yaptırıldı. Yükün, dinlenme aralığı sürelerinin ve cinsiyetin setlerdeki performansa etkisi karışık desenli 4 faktörlü tekrarlayan ölçümlerde varyans analiziyle incelendi. Bulgular: Erkek katılımcıların bench pres ve squat hareketinde 1TM kuvvet performansının genç kadınlardan önemli düzeyde yüksek olduğu saptandı (p>0,05). Bench pres ve squat hareketlerinde hem yüksek hem de düşük yükte tek başına cinsiyet faktörünün veya dinlenme aralığı ile cinsiyet faktörlerinin etkileşiminin toplam tekrar sayısı üzerine etkisinin olmadığı tespit edildi (p>0,05). Set uygulamalarında yüksek yükte yapılan egzersizlerde tekrar sayısı düşük yükte yapılan egzersizlerden daha azdı (p<0,05). Setler arasında daha uzun dinlenme aralıkları daha fazla tekrar sayısına neden oldu (p<0,05). Hem bench pres hem de squat hareketinde düşük ve yüksek yükte dinlenme aralıklarına göre setlerde tekrar sayısında meydana gelen değişimler kadın ve erkeklerde benzerdi (p>0,05). Sonuç: Hem düşük hem de yüksek yükte her 2 hareket için setler arasındaki kısa dinlenme sürelerinin tekrar sayısında daha fazla azalmaya neden olduğu, uzun dinlenme aralığının tekrar sayısını artırdığı, bu etkide cinsiyetin önemsiz olduğu söylenebilir.

Order Effects of Resistance and Stretching Exercises on Heart Rate Variability and Blood Pressure in Healthy Adults.

da Silva Araujo, G, Behm, DG, Monteiro, ER, de Melo Fiuza, AGF, Gomes, TM, Vianna, JM, Reis, MS, and da Silva Novaes, J. Order effects of resistance and stretching exercises on heart rate variability and blood pressure in healthy adults. J Strength Cond Res 33(10): 2684-2693, 2019-The purpose of this study was to compare the acute effect of different combinations and order of resistance exercise (RE) and stretching exercise (SE) on heart rate variability, systolic blood pressure (SBP), and diastolic blood pressure (DBP). Twenty subjects, recreationally trained, performed 5 sessions in a random order: (a) SE followed by RE no rest (SE + RE), (b) RE followed by SE no rest (RE + SE), (c) SE between RE sets (SBE), (d) SE isolated, and (e) RE isolated. Heart rate variability, SBP, and DBP were collected for 15 minutes before (baseline) and 60 minutes after each experimental session. A significant decrease was found for standardized deviation of differences between adjacent normal r-r intervals (RMSSDms) SE + RE (-50.79%), SE (+9.2%), SBE (-42.8%), and RE (-46.3%). Similarly, a significant increase was found for LFnu in SE + RE (+12.8%) and SBE (+16.6%). In addition, a significant decrease was found for HFnu in SE + RE (-34.8%) and SBE (-39.7%). Finally, a significant decrease was found for SBP in SE (-6.1%). In conclusion, this study indicated that SE followed by RE promotes a reduction in LFnu and RMSSDnu, with trivial to small magnitude decreases in SBP. Therefore, performing SE either before or between RE would be an important exercise prescription recommendation to lower cardiac load and consequently greater safety.

Electromyographic and Performance Analysis during Three Sets of Resistance Exercises among Untrained Women

The number of sets need to be performed in a resistance training session has been debated for decades. As more recent studies showed the superiority of performing multiple sets in resistance training, the aim of this study was to determine and compare the muscle activation and performance during three sets of resistance exercises among untrained women. Thirty-two recreationally active, untrained women were recruited as participants. Muscle activation was obtained from the pectoralis major during bench press and vastus lateralis during squat using electromyography method. Performance was measured by the number of repetitions performed in the three sets during both exercises. Results showed that the number of repetitions decreased significantly as early in the second set and continued to reduce in the third set. No significant changes were found for muscular activation. As the conclusion, among untrained women, it seems that performance in resistance training tend to decrease as early as during the second set. It is recommended for untrained women to perform more than a single set for each exercises in a resistance training to enhance their muscular strength and endurance