Comparison Between Traditional and Alternated Resistance Exercises on Blood Pressure, Acute Neuromuscular Responses, and Rating of Perceived Exertion in Recreationally Resistance-Trained Men.

ABSTRACT: Corrêa Neto, VG, Silva, DdN, Palma, A, de Oliveira, F, Vingren, JL, Marchetti, PH, da Silva Novaes, J, and Monteiro, ER. Comparison between traditional and alternated resistance exercises on blood pressure, acute neuromuscular responses, and rating of perceived exertion in recreationally resistance-trained men. J Strength Cond Res 38(5): e211-e218, 2024-The purpose of this study was to compare the acute effects of traditional and alternated resistance exercises on acute neuromuscular responses (maximum repetition performance, fatigue index, and volume load), rating of perceived exertion (RPE), and blood pressure (BP) in resistance-trained men. Fifteen recreationally resistance-trained men (age: 26.40 ± 4.15 years; height: 173 ± 5 cm, and total body mass: 78.12 ± 13.06 kg) were recruited and performed all 3 experimental conditions in a randomized order: (a) control (CON), (b) traditional (TRT), and (c) alternated (ART). Both conditions (TRT and ART) consisted of 5 sets of bilateral bench press, articulated bench press, back squat, and Smith back squat exercises at 80% 1RM until concentric muscular failure. The total number of repetitions performed across sets in the bench press followed a similar pattern for TRT and ART, with significant reductions between sets 3, 4, and 5 compared with set 1 (p < 0.05). There was a significant difference for set 4 between conditions with a lower number of repetitions performed in the TRT. The volume load was significantly higher for ART when compared with TRT. TRT showed significant reductions in BP after 10-, 40-, and 60-minute postexercise and when compared with CON after 40- and 60-minute postexercise. However, the effect size illustrated large reductions in systolic BP during recovery in both methods. Thus, it is concluded that both methods reduced postexercise BP.

Multi-Ingredient Preworkout Supplementation Compared With Caffeine and a Placebo Does Not Improve Repetitions to Failure in Resistance-Trained Women.

There has been an increase in the use of commercially available multi-ingredient preworkout supplements (MIPS); however, there are inconsistencies regarding the efficacy of MIPS in resistance-trained women. PURPOSE: To determine the effect of varying doses of MIPS compared with caffeine only (C) and a placebo (PL) on resistance-training performance in trained women. METHODS: Ten women (21.5 [2.3] y) completed 1-repetition-maximum tests at baseline for leg press and bench press. A within-group, double-blind, and randomized design was used to assign supplement drinks (ie, PL, C, MIPS half scoop [MIPS-H], and MIPS full scoop [MIPS-F]). Repetitions to failure were assessed at 75% and 80% to 85% of 1-repetition maximum for bench and leg press, respectively. Total performance volume was calculated as load × sets × repetitions for each session. Data were analyzed using a 1-way repeated-measures analysis of variance and reported as means and SDs. RESULTS: There were no differences in repetitions to failure for bench press (PL: 14.4 [3.2] repetitions, C: 14.4 [2.9] repetitions, MIPS-H: 14.2 [2.6] repetitions, MIPS-F: 15.1 [3.1] repetitions; P = .54) or leg press (PL: 13.9 [7.8] repetitions, C: 10.8 [5.9] repetitions, MIPS-H: 13.1 [7.1] repetitions, MIPS-F: 12.4 [10.7] repetitions; P = .44). Furthermore, there were no differences in total performance volume across supplements for bench press (PL: 911.2 [212.8] kg, C: 910.7 [205.5] kg, MIPS-H: 913.6 [249.3] kg, MIPS-F: 951.6 [289.6] kg; P = .39) or leg press (PL: 4318.4 [1633.6] kg, C: 3730.0 [1032.5] kg, MIPS-H: 4223.0 [1630.0] kg, MIPS-F: 4085.5 [2098.3] kg; P = .34). CONCLUSIONS: Overall, our findings suggest that caffeine and MIPS do not provide ergogenic benefits for resistance-trained women in delaying muscular failure.

A Biomechanical Comparison of the Back Squat and Hexagonal Barbell Deadlift.

ABSTRACT: Stahl, CA, Regni, G, Tanguay, J, McElfresh, M, Trihy, E, Diggin, D, and King, DL. A biomechanical comparison of the back squat and hexagonal barbell deadlift. J Strength Cond Res 38(5): 815-824, 2024-Coaches often use different exercises to encourage similar strength adaptations and limit monotony. Anecdotally, the hexagonal barbell deadlift (HBD) exhibits similarities to the back squat (BS). To date, research has not examined the empirical differences between these exercises. This study examined kinematic and kinetic differences between the BS and the HBD across different loads. Sixteen resistance-trained individuals (6 men and 10 women) volunteered to participate. Subjects performed 1-repetition maximum (1RM) testing under BS and HBD conditions. Kinematic and kinetic data were collected during performance of both exercises at submaximal (warm-up sets) and maximal (1RM) loads using a 3D motion capture and force-plate system. Results showed that subjects lifted greater 1RM loads in the HBD relative to the BS (p < 0.05; d = -1.75). Kinematic data indicated that subjects exhibited greater maximum forward lean of the trunk and decreased maximum knee flexion while performing the HBD compared with the BS. The BS resulted in higher maximum extension moments at the hip joint than the HBD. Maximum extension moments at the knee joint showed no difference between the exercises. Data suggest that bar design and position facilitate balanced moment arm length at hip and knee joints during performance of the HBD. By contrast, bar position during performance of the BS increases moment arm length at the hip joint, making it a hip-dominant exercise. The present data have implications for the programming of both exercises. Future research should examine differences in muscle-activation strategies between the 2 exercises.

Do Muscle Mass and Body Fat Differ Between Elite and Amateur Natural Physique Athletes on Competition Day? A Preliminary, Cross-Sectional, Anthropometric Study.

ABSTRACT: González-Cano, H, Martín-Olmedo, JJ, Baz-Valle, E, Contreras, C, Schoenfeld, BJ, García-Ramos, A, Jiménez-Martínez, P, and Alix-Fages, C. Do muscle mass and body fat differ between elite and amateur natural physique athletes on competition day? A preliminary, cross-sectional, anthropometric study. J Strength Cond Res 38(5): 951-956, 2024-Natural physique athletes strive to achieve low body fat levels while promoting muscle mass hypertrophy for competition day. This study aimed to compare the anthropometric characteristics of natural amateur (AMA) and professional (PRO) World Natural Bodybuilding Federation (WNBF) competitors. Eleven male natural physique athletes (6 PRO and 5 AMA; age = 24.8 ± 2.3 years) underwent a comprehensive anthropometric evaluation following the International Society for the Advancement of Kinanthropometry protocol within a 24-hour time frame surrounding the competition. The 5-component fractionation method was used to obtain the body composition profile of the muscle, adipose, bone, skin, and residual tissues. Five physique athletes exceeded the 5.2 cutoff point of muscle-to-bone ratio (MBR) for natural athletes. Professional physique athletes were older than AMA physique athletes (p = 0.05), and they also presented larger thigh girths (p = 0.005) and bone mass (p = 0.019) compared with AMA physique athletes. Although no statistically significant between-group differences were observed in body mass, height, or body fat levels, PRO physique athletes exhibited a higher body mass index (BMI; AMA: 24.45 ± 0.12; PRO: 25.52 ± 1.01; p = 0.048), lean body mass (LBM; AMA: 64.49 ± 2.35; PRO: 69.80 ± 3.78; p = 0.024), fat-free mass (FFM; AMA: 71.23 ± 3.21; PRO: 76.52 ± 4.31; p = 0.05), LBM index (LBMI; AMA: 20.65 ± 0.52; PRO: 21.74 ± 0.85; p = 0.034), and fat-free mass index index (FFMI; AMA: 22.80 ± 0.22; PRO: 23.83 ± 0.90; p = 0.037) compared with AMA physique athletes. These findings highlight the unique characteristics and anthropometric differences between PRO and AMA natural physique athletes on competition day, emphasizing the significance of age, thigh girth, bone mass, BMI, LBM, FFM, and FFMI in distinguishing these 2 groups. Based on our findings, the established boundaries for muscle mass in natural physique athletes, based on FFMI and MBR, warrant reconsideration.

Completely Plant-Based Diets That Meet Energy Requirements for Resistance Training Can Supply Enough Protein and Leucine to Maximize Hypertrophy and Strength in Male Bodybuilders: A Modeling Study.

Despite increasing awareness of plant-based diets for health and athletic performance, athletes are cautioned that careful dietary monitoring is necessary. Whether commonly consumed plant-based diets are nutritionally adequate for maximal muscular hypertrophy remains unknown. This modeling study assessed the nutrient composition of completely plant-based diets scaled to the caloric demands of maximal muscle mass and strength development in adult male bodybuilders. To model calorie requirements, anthropometric data from bodybuilders were input into the Tinsley resting metabolic rate prediction equation, and an appropriate physical activity factor and calorie surplus were applied. Dietary data from a large cohort following completely plant-based diets were then scaled to meet these needs. Modeled intakes for nutrients of interest were calculated as 1.8 g/kg/day of protein and 2.75 g/meal of leucine, which surpass mean requirements for maximal increases in muscle mass and strength and muscle protein synthesis, respectively. Daily levels for all micronutrients, except vitamin D, also exceeded requirements. Saturated fat levels were aligned with dietary guidelines, although sodium levels exceeded recommended limits. Consumption of larger portions of commonplace plant-based diets, scaled to meet the energy demands of maximal accrual of muscle mass and strength, satisfied protein and leucine requirements without the need for additional planning.

A Biomechanical Comparison Between the Safety-Squat Bar and Traditional Barbell Back Squat.

ABSTRACT: Johansson, DG, Marchetti, PH, Stecyk, SD, and Flanagan, SP. A biomechanical comparison between the safety-squat bar and traditional barbell back squat. J Strength Cond Res 38(5): 825-834, 2024-The primary objectives for this investigation were to compare the kinematic and kinetic differences between performing a parallel back squat using a traditional barbell (TB) or a safety-squat bar (SSB). Fifteen healthy, recreationally trained male subjects (23 + 4 years of age) performed the back squat with a TB and an SSB at 85% of their respective 1 repetition maximum with each barbell while instrumented for biomechanical analysis. Standard inverse dynamics techniques were used to determine joint kinematic and kinetic measures. A 2 × 3 (exercise × joint) factorial analysis of variance with repeated measures was used to determine the kinetic and kinematic differences between the squats while using the different barbells. Fisher's least significant difference post hoc comparisons showed that the TB resulted in significantly greater maximum hip flexion angle (129.33 ± 11.8° vs. 122.11 ± 12.1°; p < 0.001; d = 1.80), peak hip net joint extensor torque (2.54 ± 0.4 Nm·kg -1 vs. 2.40 ± 0.4 Nm·kg -1 ; p = 0.001; d = 1.10), hip net extensor torque mechanical energy expenditure (MEE; 2.81 ± 0.5 Nm·kg -1 vs. 2.58 ± 0.6 Nm·kg -1 ; p = 0.002; d = 0.97), and ankle net joint plantar flexor torque MEE (0.32 ± 0.09 J·kg -1 vs. 0.28 ± 0.06 J·kg -1 ; p = 0.029; d = 0.63), while also lifting significantly (123.17 ± 20.8 kg vs. 117.17 ± 20.8 kg; p = 0.005; d = 0.858) more weight than the SSB. The SSB resulted in significantly higher maximum knee flexion angles (116.82 ± 5.8° vs. 115.65 ± 5.6°; p = 0.011; d = 0.75) than the TB, with no significant difference in kinetics at the knee. The TB may be preferred to the SSB for developing the hip extensors and lifting higher maximum loads. The SSB may be advantageous in situations where a more upright posture or a lower load is preferred while creating a similar demand for the knee joint.

Comparing Video Analysis to Computerized Detection of Limb Position for the Diagnosis of Movement Control during Back Squat Exercise with Overload.

Incorrect limb position while lifting heavy weights might compromise athlete success during weightlifting performance, similar to the way that it increases the risk of muscle injuries during resistance exercises, regardless of the individual's level of experience. However, practitioners might not have the necessary background knowledge for self-supervision of limb position and adjustment of the lifting position when improper movement occurs. Therefore, the computerized analysis of movement patterns might assist people in detecting changes in limb position during exercises with different loads or enhance the analysis of an observer with expertise in weightlifting exercises. In this study, hidden Markov models (HMMs) were employed to automate the detection of joint position and barbell trajectory during back squat exercises. Ten volunteers performed three lift movements each with a 0, 50, and 75% load based on body weight. A smartphone was used to record the movements in the sagittal plane, providing information for the analysis of variance and identifying significant position changes by video analysis (p < 0.05). Data from individuals performing the same movements with no added weight load were used to train the HMMs to identify changes in the pattern. A comparison of HMMs and human experts revealed between 40% and 90% agreement, indicating the reliability of HMMs for identifying changes in the control of movements with added weight load. In addition, the results highlighted that HMMs can detect changes imperceptible to the human visual analysis.

The effects of anti-doping measures on sports performance in weightlifting.

BACKGROUND: Evaluating anti-doping measures is essential to optimise their effectiveness. Comparing sporting results that have a higher doping prevalence, such as weightlifting, before and after the implementation of anti-doping measures may serve as an effectiveness indicator. METHODS: The results of the most successful weightlifters of both sexes in two time periods, 2009-2015 and 2016-2022 were analysed. The Sinclair Total (ST) to compare the relative strength of weightlifters from different weight categories was calculated. RESULTS: A significant decrease in the ST during 2016-2022 (p < 0.001) in athletes of all ages and both sexes overall was reported. When analysed by age, there was a decrease in ST in juniors and seniors of both sexes (p = 0.010 and p < 0.001, respectively), but not in youth. There was a decrease in the ST in senior men (p < 0.001), junior women (p < 0.001) and senior women (p < 0.001). CONCLUSION: In elite weightlifting, adult athletic results declined during 2016-2022, which may partly be explained by the implementation of new methods to detect long-term anabolic androgenic steroid metabolites as well as other policies. This may highlight the effectiveness of these methods both in the prevention and detection of anti-doping rule violations.

A new sports garment with elastomeric technology optimizes physiological, mechanical, and psychological acute responses to pushing upper-limb resistance exercises.

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

The Effect of Different Weight Plate Widths (Bumper vs. Standard) on the Biomechanics of the Bench Press.

ABSTRACT: Fiedler, MJ, Triplett, NT, Hamilton, KC, Needle, AR, and van Werkhoven, H. The effect of different weight plate widths (bumper vs. standard) on the biomechanics of the bench press. J Strength Cond Res 38(4): e143-e149, 2024-Anecdotal evidence suggests that bumper plates impact lifts in powerlifting and weightlifting differently than standard cast iron plates, but whether biomechanical differences exist between lifts using bumper versus standard plates has not been investigated. Eleven resistance-trained subjects performed the bench press at 70, 80, and 90% of their 1 repetition maximum (1RM) while being blinded to whether they were lifting with bumper or standard plates. Motion data were captured by an 8-camera motion capture system, and electromyography (EMG) data were recorded for the anterior deltoid, pectoralis major, and triceps brachii. Repeated-measures analysis of variances showed a significant main weight effect for time under tension (p < 0.001), total work (p < 0.001), and muscle activity through EMG (across all muscles; p < 0.001) and a significant weight × joint interaction effect for average joint moment (p < 0.001) and peak joint moment (p < 0.001). However, there were no significant differences observed between the different weight plates for any of the measures. The main finding of the study suggests that there are no biomechanical differences between using bumper plates compared with standard plates during the bench press lift.

Effects of Eccentric Phase Velocity on Bench Press Concentric Bar Velocity in the Young and Elderly.

This study aimed to investigate the impact of bar velocity during the eccentric phase on subsequent concentric performance in the young and elderly. Twelve elderly women (65.2+4.2 years) and 16 young women (23.1+2.1 years) were randomly assigned to four experimental conditions that combined high-velocity eccentric actions (HVECC; maximum velocity) and moderate-velocity eccentric actions (MVECC; 2.0 s), using 30% and 60% of their 1-repetition maximum (1RM) on the Smith machine bench press. Measurements of mean propulsive velocity (MPV), peak velocity (PV), and mean power (MP) were recorded. Two-way ANOVA with repeated measures was applied for each variable, when needed, the Bonferroni post hoc was used. Statistical significance was set at p<0.05, and effect size (ES) was established by Cohen's d z. The results demonstrated that elderly women showed improved performance in MPV (+10.0%; ES=- 0.58; p=0.009) and MP (+11.7%; ES=- 0.14; p=0.045) when utilizing HVECC at 30% 1RM only. Moreover, young women exhibited superior performance for both 30% and 60% 1RM when using HVECC for all variables analyzed (p<0.05). The HVECC appears to have an impact on the subsequent performance of the concentric phase, particularly when lighter loads (30% 1RM) are utilized, regardless of the age group.

Successful Powerlifting in a Unilateral, Transtibial Amputee: A Descriptive Case Series.

ABSTRACT: Beausejour, JP, Guinto, G, Artrip, C, Corvalan, A, Mesa, MF, Lebron, MA, and Stock, MS. Successful powerlifting in a unilateral, transtibial amputee: A descriptive case series. J Strength Cond Res 38(5): e243-e252, 2024-There are no reports in the literature of powerlifting success after amputation. We had the unique opportunity to characterize functional outcomes, strength, muscle contractility and size, and corticospinal excitability in an accomplished, competitive powerlifter (best competition squat = 205.0 kg, deadlift = 262.7 kg) with a unilateral, transtibial amputation relative to amputee controls. Four men (age range = 23-49 years) with unilateral, lower-limb amputation (3 transtibial, 1 transfemoral) participated in 1 laboratory visit. We assessed 10-m gait speed, the timed up and go (TUG) test, 5-time sit-to-stand performance (5TSTS), contractile properties of the vastus lateralis (VL) and medial gastrocnemius by tensiomyography, and VL cross-sectional area (CSA) by ultrasonography. Unilateral assessments for the intact limb included isokinetic knee extension and flexion torque and power and transcranial magnetic stimulation derived corticospinal excitability. An interview with the powerlifter provided contextual perspective. Compared with the control subjects, the powerlifter performed the 5TSTS faster (6.8%), exhibited faster VL contraction times (intact limb = 12.2%; residual limb = 23.9%), and showed larger VL CSA for the intact limb (46.7%). The powerlifter exhibited greater knee extension and flexion peak torque and mean power, particularly at 180°·s -1 , as well as greater corticospinal excitability for the intact VL (65.6%) and tibialis anterior (79.6%). By contrast, the control subjects were faster in the TUG (18.3%) and comfortable (13.0%) and fast (21.4%) in the 10-m walk test. The major themes of our interview included needing to modify lifting mechanics, persistence, and remarkable pain tolerance. Our findings highlight the impressive neuromuscular adaptations that are attainable after lower-limb amputation.

Changes in muscular strength following nine weeks of high- or low-load resistance training.

BACKGROUND: Traditional resistance training schemes often utilize higher loads for strength gains and lower loads for muscular endurance or hypertrophy. This study aimed to investigate muscular strength adaptations after nine weeks of high- or low-load resistance training. METHODS: Seventeen recreationally-trained male lifters were recruited for this study (age 20.4±2.7 years) and split into high-load (85% 1-RM; N.=8) or low-load (30% 1-RM; N.=9), completing three whole-body training sessions per week for nine weeks. Each session included three working sets of repetitions to failure. At baseline and every three weeks after, knee extension/flexion were tested using an isokinetic dynamometer. Participants completed three 5-s MVIC and isokinetic muscle actions at 60°/s and 120°/s, with the highest torque value used in analysis. Predicted 1-RM testing was at baseline and end of training program. ANCOVAs were conducted to analyze changes in strength, with significance set at P<0.05. RESULTS: This study demonstrated similar MVIC and peak torque values for both isokinetic speeds, although there were nonsignificant decreases largely driven by the 30% group. The high-load group showed greater increases in 1-RM following the training program. CONCLUSIONS: This study suggests training with lighter loads may be detrimental for long term isokinetic strength, whereas heavier loads could result in maintenance and greater increases in 1-RM despite performing repetitions to failure.

Prediction of One Repetition Maximum in Free-Weight Back Squat Using a Mixed Approach: The Combination of the Individual Load-Velocity Profile and Generalized Equations.

ABSTRACT: Fitas, A, Santos, P, Gomes, M, Pezarat-Correia, P, Schoenfeld, BJ, and Mendonca, GV. Prediction of one repetition maximum in free-weight back squat using a mixed approach: the combination of the individual load-velocity profile and generalized equations. J Strength Cond Res 38(2): 228-235, 2024-We aimed to develop a mixed methods approach for 1 repetition maximum (1RM) prediction based on the development of generalized equations and the individual load-velocity profile (LVP), and to explore the validity of such equations for 1RM prediction. Fifty-seven young men volunteered to participate. The submaximal load-velocity relationship was obtained for the free-weight parallel back squat. The estimated load at 0 velocity (LD0) was used as a single predictor, and in combination with the slope of the individual LVP, to develop equations predictive of 1RM. Prediction accuracy was determined through the mean absolute percent error and Bland-Altman plots. LD0 was predictive of 1RM ( p < 0.0001), explaining 70.2% of its variance. Adding the slope of the LVP to the model increased the prediction power of 1RM to 84.4% ( p < 0.0001). The absolute percent error between actual and predicted 1RM was lower for the predictions combining LD0 and slope (6.9 vs. 9.6%). The mean difference between actual and estimated 1RM was nearly zero and showed heteroscedasticity for the LD0 model, but not for the combined model. The limits of agreement error were of 31.9 and 23.5 kg for LD0 and LD0 combined with slope, respectively. In conclusion, the slope of the individual LVP adds predictive value to LD0 in 1RM estimation on a group level and avoids error trends in the estimation of 1RM over the entire spectrum of muscle strength. However, the use of mixed methods does not reach acceptable accuracy for 1RM prediction of the free-weight back squat on an individual basis.

Simulation analysis of low back forces in Snatch and Clean & Jerk movements via digital human modelling.

BACKGROUND: Weightlifting is an Olympic sport for dynamic strength and power, and requires the execution of different lifting techniques It is important to analyze the forces subjected to the lower back during weightlifting movements to prevent injuries. Digital Human Modeling (DHM) is a powerful tool that can be used to analyze and optimize the performance of humans while doing their work or activities. OBJECTIVE: The purpose of this study is to present a simulation analysis of the lower back forces during the execution of two weightlifting techniques: Snatch (SN) and Clean & Jerk (CJ), with different loads and for both genders. METHODS: Digital Human modelling through JACK simulation package was used analyze the forces exerted on the lumbosacral area (L5-S1) of the lower back in order to determine the risk for low back injuries. The level of compression and shear forces recommended by the literature have been set as thresholds. The simulaitons were performed in male and female models, with loads from 20-100 kg. RESULTS: The results show that any weight higher than 60 kg in both movements poses risk for the weightlifters in terms of compression and shear forces. It has been observed that weightlifters can lift greater loads in the CJ technique compared to the SN technique. Furthermore, females are able to lift higher loads with lower risk of injuries. CONCLUSION: Weightlifting is a high-risk activity due to the high levels of shear and compression forces that the body is exposed to during the lifting techniques. Digital Human Modeling holds significant value due to their ability to facilitate the exploration of diverse conditions within a safe environment, devoid of any potential harm to human subjects.

Does Moderate-Load Priming Activity Influence Maximal Upper-Body Performance and Perceptual State?

ABSTRACT: Harrison, PW, Kelly, VG, Jenkins, DG, McGuigan, MR, Holmberg, PM, and James, LP. Does moderate-load priming activity influence maximal upper-body performance and perceptual state?. J Strength Cond Res 37(11): e581-e587, 2023-The results of previous research indicate that resistance exercise "priming" may improve strength-power measures within 48 hours after their completion. Although researchers have primarily examined performance responses after lower-body priming stimuli, investigations examining the effects of upper-body resistance priming exercises are presently limited. Therefore, the aim of this study was to examine upper-body pushing and pulling performance in addition to perceptual responses 3 and 27 hours after moderate-load (ML) upper-body resistance priming exercise. Fourteen resistance-trained men were assigned to complete ML priming (4 × 3 bench press and bench pull at 65% 1RM [repetition maximum]) and control (rest) protocols in a randomized and counterbalanced order. Peak velocity during the bench throw and bench pull tests involving different loads (25, 50, and 75% 1RM) showed no practical change at 3 and 27 hours after the priming session (p = 0.216-0.99, Cliff's d = -0.041 to 0.225). Small effect size increases in perceptual measures ("physical feeling," "physical performance," "aggression" [p = 0.400-0.553, Cliff's d = 0.183-0.201], and "muscular heaviness" [p = 0.178, Cliff's d = 0.231]) were found at 3 hours postpriming. A moderate practical increase was observed in perceived "physical feeling" compared with control (p = 0.385, Cliff's d = 0.349) in addition to small effect size increases in perceived "physical performance" and "aggression" (Cliff's d = 0.243-0.290) at 27 hours after priming activities. These results indicate that upper-body strength-power changes within 27 hours after ML upper-body resistance exercise priming are not practically meaningful.

The velocity of resistance exercise does not accurately assess repetitions-in-reserve.

This study assessed the reliability of mean concentric bar velocity from 3- to 0-repetitions in reserve (RIR) across four sets in different exercises (bench press and prone row) and with different loads (60 and 80% 1-repetition maximum; 1RM). Whether velocity values from set one could be used to predict RIR in subsequent sets was also examined. Twenty recreationally active males performed baseline 1RM testing before two randomised sessions of four sets to failure with 60 or 80% 1RM. A linear position transducer measured mean concentric velocity of repetitions, and the velocity associated with each RIR value up to 0-RIR. For both exercises, velocity decreased between each repetition from 3- to 0-RIR (p ≤ 0.010). Mean concentric velocity of RIR values was not reliable across sets in the bench press (mean intraclass correlation coefficient [ICC] = 0.40, mean coefficient of variation [CV] = 21.3%), despite no significant between-set differences (p = 0.530). Better reliability was noted in the prone row (mean ICC = 0.80, mean CV = 6.1%), but velocity declined by 0.019-0.027 m·s-1 (p = 0.032) between sets. Mean concentric velocity was 0.050-0.058 m·s-1 faster in both exercises with 60% than 80% 1RM with (p < 0.001). At the individual level, the velocity of specific RIR values from set one accurately predicted RIR from 5- to 0-RIR for 30.9% of repetitions in subsequent sets. These findings suggest that velocity of specific RIR values vary across exercises, loads and sets. As velocity-based RIR estimates were not accurate for 69.1% of repetitions, alternative methods to should be considered for autoregulating of resistance exercise in recreationally active individuals.

Bar velocity of bench press and prone row repetitions decreases on average from 3- to 0-repetitions in reserve (RIR) and is faster for lighter versus heavier loadsThe velocity of 3- to 0-RIR varied across four sets for the prone row but was more reliable for the prone row than the bench pressAt the individual participant level, there was not a consistent decrease in velocity between consecutive repetitions, and target velocities for specific RIR values were not correctly predicted in most cases.Using velocity stops may not be an appropriate method to predict specific RIR in recreationally active individuals.

The general nutrition practices of competitive powerlifters vary by competitive calibre and sex, weight, and age class.

PURPOSE: To characterise self-reported nutrition practices and beliefs of powerlifters. METHODS: Actively competing male (n = 240) and female (n = 65) powerlifters completed a cross-sectional online survey of self-reported nutrition practices across the competitive cycle, within specific competitive phases, and hard and easy training days. Data are presented as number (n) and percentage (%) of all powerlifters practicing a given strategy followed by a % of responses reporting various practices or beliefs within this strategy. Differences in categorical sub-groups (sex, age, and weight class; and competitive calibre) were analysed with a chi-square test and denoted where significant (p ≤ 0.05). RESULTS: Most powerlifters reported following a specific diet long-term (n = 203, 66.6%) of which If It Fits Your Macros (IIFYM)/flexible dieting was most common (n = 159, 78.3%). Over half reported introducing a special diet for a competitive phase (n = 162, 53.1%), of which IIFYM/flexible dieting was most followed for competition preparation (n = 80, 63%) and off-season (n = 48, 71.6%). Compared to normal dietary intake, most reported eating more on harder training days (n = 219, 71.8%) and refraining from eating less on easier training days (n = 186, 61%). CONCLUSIONS: IIFYM/flexible dieting is commonly followed by powerlifters to support performance and body composition goals. Females seemed to report more often restricting energy and dieting for body composition reasons than males. Powerlifters tailor their energy intake on harder training days to the higher training demands but refrain from reducing energy intake on rest/easier training days.

The Effects of Palm Cooling on Physiological and Metabolic Responses, Exercise Performance, and Total Volume During High-Intensity Bench Press Exercise in Resistance-Trained Men.

ABSTRACT: McMahon, G, and Kennedy, R. The effects of palm cooling on physiological and metabolic responses, exercise performance, and total volume during high-intensity bench press exercise in resistance-trained men. J Strength Cond Res 37(11): 2122-2129, 2023-Previous research suggests that cooling distal to the working agonist muscles during the interset rest periods of high-intensity resistance exercise may facilitate improved performance by means of improving metabolic conditions of contractile machinery. However, these studies have not directly measured indicators of metabolic conditions. Therefore, the aim of this study was to compare 2 palm-cooling conditions with a thermoneutral condition during high-intensity resistance exercise and subsequent effects on physiological and metabolic responses and exercise performance. Eleven healthy, resistance-trained, young men (20-36 years old) performed 4 sets of bench press exercise to exhaustion at 80% 1 repetition maximum each separated by 3 minutes of passive recovery. Palm cooling (10° C [TEN] or 15° C [FTN]) or thermoneutral (28° C [CON]) condition was applied for 60 seconds during the recovery interval of each set in a randomized, double-blind fashion, with 4 days recovery between the experimental conditions. There were no differences ( p > 0.05) in volume load between the experimental conditions across all sets. Mean repetition velocity and force of the bench press declined significantly following set 1 in all conditions ( p < 0.05), but there were no differences between the conditions. Lactate, heart rate, and rating of perceived exertion systematically increased from sets 1 to 4; however, there were no significant differences ( p > 0.05) between any of the conditions. Palm cooling at either 10 or 15° C had no observable effects on physiological and metabolic responses during exercise, nor has it any effect on bench press performance or volume load compared with a thermoneutral condition. Therefore, cooling cannot be currently recommended as an ergogenic strategy to enhance acute bench press performance or mitigate fatigue during high-intensity resistance training.

Drop-Set Resistance Training versus Pyramidal and Traditional Sets Elicits Greater Psychophysiological Responses in Men.

We compared the effects of resistance training (ResisT) to pyramidal and traditional weightlifting sets on men's psychophysiological responses. In a randomized crossover design, 24 resistance-trained males performed drop-set, descending pyramid, and traditional ResisT in the barbell back squat, 45° leg press, and seated knee extension. We assessed participants' rating of perceived exertion (RPE) and feelings of pleasure/displeasure (FPD) at the end of each set and at 10, 15, 20, and 30 minutes post-session. No differences were detected across ResisT Methods in total training volume (p = 0.180). Post hoc comparisons revealed that drop-set training elicited higher RPE (M 8.8 SD 0.7 arbitrary units) and lower FPD (M -1.4 SD 1.5 arbitrary units) values compared to descending pyramid (M Set RPE 8.0 SD 0.9 arbitrary units and M Set FPD 0.4 SD 1.6 arbitrary units) and traditional set (M Set RPE 7.5 SD 1.1 arbitrary units and M Set FPD 1.3 SD 1.2 arbitrary units) schemes (p < 0.05). In addition, drop-set training elicited higher session RPE (M 8.1 SD 0.8 arbitrary units) and lower session FPD (M 0.2 SD 1.4 arbitrary units) values than descending pyramid and traditional ResisT (p < 0.001). Similarly, descending pyramid training elicited higher session RPE (M 6.6 SD 0.9 arbitrary units) and lower session FPD (M 1.2 SD 1.4 arbitrary units) than traditional set (M Session RPE 5.9 SD 0.8 arbitrary units and M Session FPD 1.5 SD 1.2 arbitrary units) training (p = 0.015). No differences were found in the temporality of post-session metrics, suggesting that testing 10 and 15 minutes post-ResisT was sufficient to assess session RPE (p = 0.480) and session FPD (p = 0.855), respectively. In conclusion, even with similar total training volume, drop-set training elicited more pronounced psychophysiological responses than either pyramidal or traditional ResisT in resistance-trained males.