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The aim of this study was to verify and compare the effects of electromyostimulation training (EMS), strength training (ST), and both combined (STEMS), through the analysis of the elbow flexors muscle thickness. Forty subjects (24.45 ± 3.53 years), were randomly divided equally in 4 groups: 3 experimental groups and 1 control group. Each experimental group was submitted to one of three interventions, either an ST protocol, an EMS protocol, or a STEMS protocol. The control group (CG) did not perform any type of physical activity. Ultrasonography (US) was used to measure muscle thickness (MT) at 50 and 60% of the distance between the acromion and the olecranon. The results showed a significant difference in the elbow flexors muscle thickness after 8 weeks, both in the STG, EMSG, and STEMSG, but not in the CG. However, no significant differences were observed between the intervention protocols. It seems that an increase in MT can be obtained using either with ST, EMS, or both combined, however, the results doesn't support the overlap of one method in relation to the others. EMS can be another interesting tool to induce muscle hypertrophy, but not necessarily better.

Post-exercise hypotension is of great clinical relevance and also in sports training settings, as recovery speed is important. The aim of this study was to compare the influence of different recovery methods on post-exercise hemodynamic response. Twelve male paraplegic sportsmen (25.40 ± 3.30 years) performed a strength training (ST) session using the bench press exercise. After the ST, three recovery methods were randomly performed over a 15-min period: passive recovery (PR), cold-water (CW) and dry needle (DN). Blood pressure (BP), heart rate (HR) and myocardial oxygen were measured before and post ST, as well as post the recovery method. Results: Dry needling induced lower systolic blood pressure (SBP) immediately after the treatment when compared with the other recovery methods, but the contrary was observed at 50 and 60-min post recovery, where records with DN exhibit higher mean values (η 2 p = 0.330). There were no differences in post-exercise diastolic BP and mean BP between recovery methods. There was a significantly higher HR after the PR method, when compared with CW and with DN (η 2 p = 0.426). The same was observed for double product and for myocardial oxygen, though with a larger effect size (η 2 p = 0.446). We conclude that dry needling seems to induce a faster SBP lowering immediately after the procedure but at 50-min post procedure the cold-water method showed better result. As for HR, both procedures (DN and CW) showed a better recovery when compared with passive recovery, along the several moments of measurement.

Abstract: Simão, R, Polito, M, de Salles, BF, Marinho, DA, Garrido, ND, Santos Junior, ERT, and Willardson, JM. Acute and long-term comparison of fixed vs. self-selected rest interval between sets on upper-body strength. J Strength Cond Res 36(2): 540-544, 2022-The effects of different rest interval durations between sets has been widely studied, but only recently, the self-selected rest interval (SSRI) has been a matter of interest. However, previous studies comparing fixed and SSRI have investigated only acute responses. The purpose of this study was to analyze the acute and long-term effects of a fixed rest interval (FRI) vs. an SSRI between sets on upper-body performance and strength gains. Thirty-three trained men were randomly divided into 2 groups: FRI (75 seconds between sets), and SSRI. Both groups performed 3 sets with 75% of 1-repetition maximum until repetition failure in the chest press (CP), lat pull-down (LPD), shoulder press (SP), and seated row (SR) 3 times a week for 8 weeks. The results demonstrated that the SSRI allowed for significantly greater repetition performance vs. the FRI in the CP (26.1 ± 2.0 vs. 21.5 ± 1.8), LPD (30.1 ± 2.3 vs. 24.9 ± 1.9), SP (24.0 ± 2.8 vs. 17.4 ± 1.5), and SR (26.3 ± 1.6 vs. 22.0 ± 1.6). In addition, the following strength gains were observed: SSRI (CP: 6.8%, LPD: 8.0%, SP: 6.7%, SR: 7.8%) and FRI (CP: 7.4%, LPD: 6.7%, SP: 6.1%, SR: 7.0%) without significant differences between the groups. In conclusion, within an 8-week period, both protocols seem to be effective for strength gains, despite the higher training volume accomplished by the SSRI group. However, the FRI was 37% more time efficient., (Copyright © 2020 National Strength and Conditioning Association.)

Background: Recovery from training is vital as it ensures training and performance to continue at high intensities and longer durations to stimulate the body and cause further adaptations., Objective: To evaluate different methods of post-workout recovery in Paralympic powerlifting athletes., Methods: Twelve male athletes participated (25.4 ± 3.3 years; 70.3 ± 12.1 kg). The presence of muscle edema, pain threshold, plasma cytokines, and performance measurement were evaluated five times. The recovery methods used in this study were passive recovery (PR), dry needling (DN), and cold-water immersion (CWI)., Results: The data analysis showed that the maximal force decreased compared to the pretest value at 15 min and 2 h. The results also revealed that CWI and DN increased Interleukin 2 (IL-2) levels from 24 to 48 h more than that from 2 h to 24 h. After DN, muscle thickness did not increase significantly in any of the muscles, and after 2 h, muscle thickness decreased significantly again in the major pectoralis muscle. After CWI, pain pressure stabilized after 15 min and increased significantly again after 2 h for acromial pectoralis., Conclusion: The strength training sessions generate several changes in metabolism and different recovery methods contribute differently to maintain homeostasis in Paralympic powerlifting athletes.

Objective: The purpose of this study was to verify the acute effects of different exercise orders and rest intervals between sets on young athletes performance., Method: Sixteen young male football players (73.2 ± 4.8 kg, 177.5 ± 5.1 cm, BMI 23.2 ± 1.1, 19.8 ± 0.9 years) completed six experimental strength training (ST) sessions with different exercise order sequences (A and B) and rest interval lengths (1 min, 3 min, and self-selected).In Sequence A the exercises were: bench press (BP), back squat (BS), biceps curl (BC) and plantar flexion (PF); while Sequence B was performed in the opposite order (i.e. PF, BC, BS and BP).The total work volume (TWV) per exercise (sets x repetitions x load) and per training session (sum of the TWV of all exercises) were evaluated for all ST sessions., Results: BC and PF exercises presented higher TWV in sequence B (p ≤ 0.05). Already, the exercises BP, BS and PF presented higher TWV with 3 min and self-selected rest intervals (p ≤ 0.05). The 3-min and self-selected rest intervals presented higher values of TWV per training session compared to the 1-min rest interval (p ≤ 0.05)., Conclusion: The exercise order influenced certain exercises (BC and PF), which presented higher TWV when positioned at the beginning of a sequence. While the longer rest intervals (3 min and self-selected) resulted in higher TWV per exercise (BP, BS and PF) and per training session. These results suggest that self-selected rest interval can be implemented to increase training efficiency in young athletes., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to this article., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The aim of the present study was to assess the accuracy of heart rate to estimate energy cost during eight resistance exercises performed at low intensities: half squat, 45° inclined leg press, leg extension, horizontal bench press, 45° inclined bench press, lat pull down, triceps extension and biceps curl. 56 males (27.5 ± 4.9 years, 1.78 ± 0.06 m height, 78.67 ± 10.7 kg body mass and 11.4 ± 4.1% estimated body fat) were randomly divided into four groups of 14 subjects each. Two exercises were randomly assigned to each group and subjects performed four bouts of 4-min constant-intensity at each assigned exercise: 12%, 16%, 20% and 24% 1-RM. Exercise and intensity order were random. Each subject performed no more than 2 bouts in the same testing session. A minimum recovery of 24h was kept between sessions. During testing VO2 was measured with Cosmed K4b2 and heart rate was measured with Polar V800 monitor. Energy cost was calculated from mean VO2 during the last 30-s of each bout by using the energy equivalent 1 ml O2 = 5 calorie. Linear regressions with heart rate as predictor and energy cost as dependent variable were build using mean data from all subjects. Robustness of the regression lines was given by the scatter around the regression line (Sy.x) and Bland-Altman plots confirmed the agreement between measured and estimated energy costs. Significance level was set at p≤0.05. The regressions between heart rate and energy cost in the eight exercises were significant (p<0.01) and robustness was: half squat (Sy.x = 0,48 kcal·min-1), 45° inclined leg press (Sy.x = 0,54 kcal·min-1), leg extension (Sy.x = 0,59 kcal·min-1), horizontal bench press (Sy.x = 0,47 kcal·min-1), 45° inclined bench press (Sy.x = 0,54 kcal·min-1), lat pull down (Sy.x = 0,28 kcal·min-1), triceps extension (Sy.x = 0,08 kcal·min-1) and biceps curl (Sy.x = 0,13 kcal·min-1). We conclude that during low-intensity resistance exercises it is possible to estimate aerobic energy cost by wearable heart rate monitors with errors below 10% in healthy young trained males., Competing Interests: The authors have declared that no competing interests exist.

Oxygen uptake (VO 2 ) kinetics has been analyzed through mathematical modeling of constant work-rate exercise, however, the exponential nature of the VO 2 response in resistance exercise is currently unknown. The present work assessed the VO 2 on-kinetics during two different sub maximal intensities in the inclined bench press and in the seated leg extension exercise. Twelve males (age: 27.2 ± 4.3 years, height: 177 ± 5 cm, body mass: 79.0 ± 10.6 kg and estimated body fat: 11.4 ± 4.1%) involved in recreational resistance exercise randomly performed 4-min transitions from rest to 12% and 24% of 1 repetition maximum each, of inclined bench press (45°) and leg extension exercises. During all testing, expired gases were collected breath-by-breath with a portable gas analyzer (K4b 2 , Cosmed, Italy) and VO 2 on-kinetics were identified using a multi-exponential mathematical model. Leg extension exercise exhibited a higher R-square, compared with inclined bench press, but no differences were found in-between exercises for the VO 2 kinetics parameters. VO 2 on-kinetics seems to be more sensitive to muscle related parameters (upper vs. lower body exercise) and less to small load variations in the resistance exercise. The absence of a true slow component indicates that is possible to calculate low-intensity resistance exercise energy cost based solely on VO 2 measurements.

The purpose of this study was to learn the interplay between dry-land strength and conditioning, and stroke biomechanics in young swimmers, during a 34-week training programme. Twenty-seven swimmers (overall: 13.33 ± 0.85 years old; 11 boys: 13.5 ± 0.75 years old; 16 girls: 13.2 ± 0.92 years old) competing at regional- and national-level competitions were evaluated. The swimmers were submitted to a specific in-water and dry-land strength training over 34 weeks (and evaluated at three time points: pre-, mid-, and post-test; M1, M2, and M3, respectively). The 100-m freestyle performance was chosen as the main outcome (i.e. dependent variable). The arm span (AS; anthropometrics), throwing velocity (TV; strength), stroke length (SL), and stroke frequency (SF; kinematics) were selected as independent variables. There was a performance enhancement over time (M1 vs. M3: 68.72 ± 5.57 s, 66.23 ± 5.23 s; Δ = -3.77%; 95% CI: -3.98;-3.56) and an overall improvement of the remaining variables. At M1 and M2, all links between variables presented significant effects (p < .001), except the TV-SL and the TV-SF path. At M3, all links between variables presented significant effects (p ≤ .05). Between M1 and M3, the direct effect of the TV to the stroke biomechanics parameters (SL and SF) increased. The model predicted 89%, 88%, and 92% of the performance at M1, M2, and M3, respectively, with a reasonable adjustment (i.e. goodness-of-fit M1: χ 2 /df = 3.82; M2: χ 2 /df = 3.08; M3: χ 2 /df = 4.94). These findings show that strength and conditioning parameters have a direct effect on the stroke biomechanics, and the latter one on the swimming performance.

Background: This study aimed to evaluate the effect of resistance training on the functional capacity of people with multiple sclerosis. Two groups were defined intentionally and divided based on the Expanded Disability Status Scale (EDSS): an experimental group (EG) consisting of 11 individuals, 18.2% with an EDSS Score of 0-3.0, 72.8% with a score of 3.5-5.5 and 9.1% with a score of 6.0-7.5; and a control group (CG) consisting of 12 subjects, 25.0% with a score of 0-3.0, 58.3% with a score of 3.5-5.5 and 16.7% with a score of 6.0-7.5., Methods: The EG underwent 12 weeks of resistance training, while the CG did not. The Timed "Up & Go" test was used to measure the function of the lower limbs. The Timed 7.62 Meters Walk test and the Sit-to-stand test were used to assess the strength of the lower limbs. Balance, and the risk of falling, were assessed through the Berg Balance Test., Results: At the beginning of the study, there were no differences between EG and CG in lower limb function. However, after the 12 weeks of resistance training, significant differences were found between the EG and the CG in the Timed "Up and Go" test (P=0.021), Timed 7.62 Meters Walk (P=0.027), Sit-to-stand (P=0.017) and Balance test (P=0.039)., Conclusions: This study's results indicate that this type of training can improve muscle strength and functional capacity in patients with multiple sclerosis.

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The purpose of this study was to investigate the acute effects of multi-joint resistance exercises (MJRE) with blood flow restriction on hormonal responses. Ten men participated in the study and underwent two experimental protocols in random order: four sets (30, 15, 15, and 15 reps, respectively) of MJRE (half squat and horizontal chest press) were performed with 20% of 1RM and a rest time between sets of 30 s, combined with intermittent blood flow restriction (LI + BFR protocol); and four sets (8, 8, 8, 20 reps, respectively) of the same MJRE performed with 75% of 1RM load (HI protocol), with a 90 s rest between the first three sets and 30 s between the third to the fourth set. Blood samples were collected before (PRE), immediately after (POST), and 15 min after the performance of MJRE (POST15). A time effect was observed for growth hormone (GH) and insulin-like-growth-factor-1-binding-protein-3 (IGFPB-3), but no protocol effects or interactions between protocol and times were observed (p > 0.05). There was no effect of either protocol or time (p > 0.05) on total testosterone, free testosterone, or cortisol concentrations. However, significant (p < 0.05) increases were observed in the GH serum concentrations of 2072.73% and 2278.5%, HI, and LI + BFR protocols, respectively, from the PRE to POST15 test. In addition, there was an increase of 15.30% and 13.29% in the IGFPB-3 concentrations (p < 0.05) from PRE to POST0 times for HI and LI + BFR protocols, respectively. Furthermore, there was a decrease of −6.17% and −11.54%, p = 0.00, between the times POST0 to POST15 in the IGFPB-3 for the HI and LI + BFR protocols, respectively. It is concluded that multi-joint resistance exercises combined with intermittent blood flow restriction seemed to promote acute hormonal responses in a manner similar to traditional exercise with high loads. Future studies may investigate whether chronic use of LI + BFR with MJRE may promote muscle hypertrophy. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the responses of creatine kinase (CK) and lactate dehydrogenase (LDH) after performing different resistance and aerobic exercise protocols. Twelve recreationally trained men (age, 23.2 ± 5.6 years; body mass, 84.3 ± 9.3 kg; body height, 178.9 ± 4.5 cm; and BMI, 26.3 ± 2.3 kg·m2) volunteered to participate in this study. All subjects were randomly assigned to four experimental protocols (crossover): (a) aerobic training at 60% of VO2max, (b) aerobic training at 80% of VO2max, (c) a resistance exercise (RE) session with a bi-set protocol, and (d) an RE session with a multiple sets protocol. Blood samples were collected before, immediately after and 24 hours following the experimental protocols. After 24 hours, there was a significant increase in CK for the 80% of VO2max protocol vs. the bi-set RE session (p = 0.016). Immediately after the protocols, we observed a significant increase in LDH among certain groups compared to others, as follows: multiple sets RE session vs. 60% of VO2max, bi-set RE session vs. 60% of VO2max, multiple sets RE session vs. 80% of VO2max, and bi-set RE session vs. 80% of VO2max (p = 0.008, p = 0.013; p = 0.002, p = 0.004, respectively). In conclusion, aerobic exercise performed at 80% of VO2max appears to elevate plasma CK levels more than bi-set RE sessions. However, the bi-set and multiple sets RE sessions appeared to trigger greater levels of blood LDH compared to aerobic protocols performed at 60% and 80% of VO2max. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the values of oxygen uptake (VO2) during and after strength training exercises (STe) and ergometer exercises (Ee), matched for intensity and exercise time. Eight men (24 ± 2.33 years) performed upper and lower body cycling Ee at the individual's ventilatory threshold (VE/VCO2). The STe session included half squats and the bench press which were performed with a load at the individual blood lactate concentration of 4 mmol/l. Both sessions lasted 30 minutes, alternating 50 seconds of effort with a 10 second transition time between upper and lower body work. The averaged overall VO2 between sessions was significantly higher for Ee (24.96 ± 3.6 ml·kg·min-1) compared to STe (21.66 ± 1.77 ml·kg·min-1) (p = 0.035), but this difference was only seen for the first 20 minutes of exercise. Absolute VO2 values between sessions did not reveal differences. There were more statistically greater values in Ee compared to STe, regarding VO2 of lower limbs (25.44 ± 3.84 ml·kg·min-1 versus 21.83 ± 2·24 ml·kg·min-1; p = 0.038) and upper limbs (24.49 ± 3.84 ml·kg·min-1 versus 21.54 ± 1.77 ml·kg·min-1; p = 0.047). There were further significant differences regarding the moment effect (p<0.0001) of both STe and Ee sessions. With respect to the moment × session effect, only VO2 5 minutes into recovery showed significant differences (p = 0.017). In conclusion, although significant increases in VO2 were seen following Ee compared to STe, it appears that the load/intensity, and not the material/equipment used for the execution of an exercise, are variables that best influence oxygen uptake. [ABSTRACT FROM AUTHOR]

High blood pressure (HBP) has been associated with several complications and causes of death. The objective of the study was to analyze the hemodynamic responses in Paralympic bench press powerlifting (PP) and conventional powerlifting (CP) before and after training and up to 60 minutes (min) after training. Ten PP and 10 CP athletes performed five sets of five repetition maximal bench press exercises, and we evaluated systolic, diastolic, and mean blood pressure (SBP, DBP, and MBP, respectively), heart rate (HR), heart pressure product (HPP), and myocardial oxygen volume (MVO2). The SBP increased after training (p < 0.001), and there were differences in the post training and 30, 40, and 60 min later (p = 0.021), between 10 and 40 min after training (p = 0.031, η2p = 0.570), and between CP and PP (p =0.028, η2p = 0.570). In the MBP, there were differences between before and after (p = 0.016) and 40 min later (p = 0.040, η2p = 0.309). In the HR, there was a difference between before and after, and 5 and 10 min later (p = 0.002), and between after and 10, 20, 30, 40, 50, and 60 min later (p < 0.001, η2p = 0.767). In HPP and MVO2, there were differences between before and after (p = 0.006), and between after and 5, 10, 20, 30, 40, 50, and 60 min later (p < 0.001, η2p = 0.816). In CP and PP, there is no risk of hemodynamic overload to athletes, considering the results of the HPP, and training promotes a moderate hypotensive effect, with blood pressure adaptation after and 60 min after exercise. [ABSTRACT FROM AUTHOR]

Background: Variable resistance training has recently become a component of strength and conditioning programs. Objective: This randomized counterbalanced cross-over study aimed to investigate the use of elastic bands (EB) and the traditional method (TRAD) and force indicators in a training session. Methods: 12 Paralympic athletes (age: 28.60 ± 7.60 years) participated in this three-week study. In the first week, the participants were familiarized with EB and TRAD and were tested for maximal repetition (1-RM). The research occurred in weeks 2 and 3, which included the pre-post training, during which the following measures were extracted: maximum isometric force (MIF), the peak torque (PT), rate of force development (RFD), fatigue index (FI), and time to MIF (Time). The athletes performed two tests, EB and TRAD, separated by a one-week interval. Results: Significant differences were found between the pre- and post-test for 1RM (p = 0.018, η2p = 0.412), MIF (p = 0.011, η2p = 0.415), PT (p = 0.012, η2p = 0.413), and RFD (p = 0.0002, η2p = 0.761). With the use of EB, there was a difference in RFD between TRAD before and EB after (p = 0.016, η2p = 0.761). There were significant differences in the before and after for FI between TRAD and EB (p < 0.001) and for Time (p < 0.001), indicating that training with the use of elastic bands promotes overload, characterized by increased fatigue and decreased strength. Conclusions: Training with EB did not decrease 1RM, PT, MIF or RFD, however, there was an increase in fatigue and time to reach MIF when compared to the method with fixed resistance. [ABSTRACT FROM AUTHOR]

(1) Background: the present study aimed to evaluate the effect of different types of warm-ups on the strength and skin temperature of Paralympic powerlifting athletes. (2) Methods: the participants were 15 male Paralympic powerlifting athletes. The effects of three different types of warm-up (without warm-up (WW), traditional warm-up (TW), or stretching warm-up (SW)) were analyzed on static and dynamic strength tests as well as in the skin temperature, which was monitored by thermal imaging. (3) Results: no differences in the dynamic and static indicators of the force were shown in relation to the different types of warm-ups. No significant differences were found in relation to peak torque (p = 0.055, F = 4.560, η2p = 0.246 medium effect), and one-repetition maximum (p = 0.139, F = 3.191, η2p = 0.186, medium effect) between the different types of warm-ups. In the thermographic analysis, there was a significant difference only in the pectoral muscle clavicular portion between the TW (33.04 ± 0.71 °C) and the WW (32.51 ± 0.74 °C) (p = 0.038). The TW method also presented slightly higher values than the SW and WW in the pectoral muscles sternal portion and the deltoid anterior portion, but with p-value > 0.05. (4) Conclusions: the types of warm-ups studied do not seem to interfere with the performance of Paralympic Powerlifting athletes. However, the thermal images showed that traditional warm-up best meets the objectives expected for this preparation phase. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze the effects of the combination of resistance training (RT) and the hydroethanolic extract (EHE) of Bowdichia virgilioides as markers of oxidative stress (OS) in rats with peripheral nerve injury (PNI). Rats were allocated into six groups (n = 10): animals without interventions (C), animals with an exposed nerve but without injury, injured animals, trained and injured animals, injured animals that received EHE, and animals that received a combination of RT and EHE. RT comprised the climbing of stairs. EHE was orally administered (200 mg/kg) for 21 days after PNI induction. RT reduced the amount of lipoperoxidation in plasma (14.11%). EHE reduced lipoperoxidation in the plasma (20.72%) and the brain (41.36). RT associated with the extract simultaneously reduced lipoperoxidation in the plasma (34.23%), muscle (25.13%), and brain (43.98%). There was an increase in total sulhydrilyl levels (a) in the brain (33.33%) via RT; (b) in the brain (44.44%) and muscle (44.51%) using EHE; and (c) in the plasma (54.02%), brain (54.25%), and muscle using the combination of RT + EHE. These results suggest that RT associated with oral EHE results in a decrease in OS. [ABSTRACT FROM AUTHOR]