1RM Performance Research Articles

A Comparison of Three Protocols for Determining Barbell Bench Press Single Repetition Maximum, Barbell Kinetics, and Subsequent Measures of Muscular Performance in Resistance-Trained Adults

Background: One repetition maximum (1RM) is a vital metric for exercise professionals, but various testing protocols exist, and their impacts on the resulting 1RM, barbell kinetics, and subsequent muscular performance testing are not well understood. This study aimed to compare two previously established protocols and a novel self-led method for determining bench press 1RM, 1RM barbell kinetics, and subsequent muscular performance measures. Methods: Twenty-four resistance-trained males (n = 12, 24 ± 6.1 years) and females (n = 12, 22.5 ± 5.5 years) completed three laboratory visits in a randomized crossover fashion. During each visit, a 1RM was established using one of the three protocols followed by a single set to volitional fatigue using 80% of their 1RM. A Sex:Protocol repeated measures ANOVA was used to determine the effects of sex and differences between protocols. Results: No significant differences were observed between the protocols for any measure, except for 1RM peak power (p = 0.036). Post hoc pairwise comparisons failed to identify any differences. Males showed significantly higher 1RM, average, and peak power (ps < 0.001), while females demonstrated a greater average concentric velocity (p = 0.031) at 1RM. Conclusions: These data suggest the protocol used to establish 1RM may have minimal impact on the final 1RM, 1RM barbell kinetics, and subsequent muscular endurance in a laboratory setting.

Kinetics and Kinematics of the Push Press, Push Jerk, and Split Jerk.

Abstract Soriano, MA, Jiménez-Ormeño, E, Lake, JP, McMahon, JJ, Gallo-Salazar, C, Mundy, P, and Comfort, P. Kinetics and kinematics of the push press, push jerk, and split jerk. J Strength Cond Res 38(8): 1359–1365, 2024—The aim of this study was to explore the kinetics and kinematics across incremental loads with the push press (PP), push jerk (PJ), and split jerk (SJ). Eighteen resistance-trained men performed the 1 repetition maximum (1RM) tests (visit 1) 3–7 days before an incremental loading protocol (60, 75, and 90% 1RM) of the 3 exercises (visit 2). Kinetics and kinematics were derived from force-time data and compared using a repeated-measures analysis of variance with load and exercise as within-subject factors. Dependent variables for the biomechanics assessment were categorized as output (power and impulse), driver (force and work), and strategy (displacement and duration) metrics. The interrepetition reliability was assessed using the intraclass correlation coefficient and coefficient of variation. The PP, PJ, and SJ 1RM performance were 89.7 ± 15.4, 95.6 ± 14.4, and 103.0 ± 16.9 kg, respectively. Driver, strategy, and outcome metrics displayed moderate-to-excellent (intraclass correlation coefficient: 0.58–0.98) reliability with acceptable variability (% coefficient of variation: 2.02–10.00). Increased load resulted in significantly large increases in force, work, displacement, duration, power, and impulse (p < 0.001, = 0.534–0.903). Exercise selection had a significant and large effect on power, impulse, work, and force (p < 0.016, = 0.387–0.534). There was a significant and large effect of load × exercise interaction on work, displacement, and duration (p < 0.019, = 0.158–0.220). Practitioners are encouraged to use heavier loads (90 > 75 > 60% 1RM) during the SJ exercise to maximize output, driver, and strategy kinetics and kinematics.

Predicting one repetition maximum in novice males: An RPE-based bench press model

This study aimed to estimate one repetition maximum (1RM) of healthy males based on the Rating of Perceived Exertion (RPE) in bench press movement and to provide a particular predictive equation. Seventy healthy males (Age: 24.93 ± 0.64 years; BMI: 25.04 ± 0.35 kg/m2) with no previous experience of resistance training performed 1RM of bench press with closed eyes and then chose a number to determine the intensity by RPE scale of 1–10 (CR1-10 scale). The intensity of this repetition was randomly selected based on the percentages of 1RM: 60%, 65%, 70%, 75%, 80%, 85%, 90% and 95%. A special prediction equation was provided based on a mathematical model using the weight lifted, RPE, and RPE coefficient. Moreover, the standardized testing protocol of 1RM (STP) and Brzycki equation protocol (BEP) were used to verify the validity of the RPE equation. Predictive equations were produced and cross-validated using repeated k-fold cross-validation by stepwise multiple linear regression. BEP and STP did not differ significantly from RPE-equation in predicting 1RM (p > 0.05). Based on the BEP and STP, a 1RM attempt for inexperienced males resulted in 74.20 ± 2.24 kg and 77.47 ± 2.17, respectively, while the RPE equation produced 77.86 ± 2.58 kg. There were significant results for linear regression (p = 0.001). Pearson correlation coefficients between BEP and STP with predicted 1RM were 0.99. The new method of 1RM based on RPE performed well in 1RM performance in inexperienced males, and it appeared safe, accurate, and time-effective.

Can the Velocity of a 1RM Hang Power Clean Be Used to Estimate a 1RM Hang High Pull?

Suchomel, TJ, Techmanski, BS, Kissick, CR, and Comfort, P. Can the velocity of a 1RM hang power clean be used to estimate a 1RM hang high pull? J Strength Cond Res 38(7): 1321-1325, 2024-The purpose of this study was to estimate the 1-repetition maximum hang high pull (1RM HHP) using the peak barbell velocity of a 1RM hang power clean (HPC). Fifteen resistance-trained men (age = 25.5 ± 4.5 years, body mass = 88.3 ± 15.4 kg, height = 176.1 ± 8.5 cm, relative 1RM HPC = 1.3 ± 0.2 kg·kg-1) with previous HPC experience participated in 2 testing sessions that included performing a 1RM HPC and HHP repetitions with 20, 40, 60, and 80% of their 1RM HPC. Peak barbell velocity was measured using a linear position transducer during the 1RM HPC and HHP repetitions performed at each load. The peak barbell velocity achieved during the 1RM HPC was determined as the criterion value for a 1RM performance. Subject-specific linear regression analyses were completed using slope-intercept equations created from the peak velocity of the 1RM HPC and the peak barbell velocities produced at each load during the HHP repetitions. The peak barbell velocity during the 1RM HPC was 1.74 ± 0.30 m·s-1. The average load-velocity profile showed that the estimated 1RM HHP of the subjects was 98.0 ± 19.3% of the 1RM HPC. Although a 1RM HHP value may be estimated using the peak barbell velocity during the HPC, strength and conditioning practitioners should avoid this method because of the considerable variation within the measurement. Additional research examining different methods of load prescription for weightlifting pulling derivatives is needed.

The Effect of Lifting Straps Use on Isometric Mid-Thigh Pull Strength Performance

This study investigated the effect of lifting strap usage on isometric mid-thigh pull performance. The study was conducted on 20 healthy males with a mean age (mean ± standard deviation) of 20.8 ± 1.5 years and mean height and weight of 177.2 ± 1.6 cm and 73.8 ± 2.9 kg, respectively. Isometric mid-thigh pull performance was measured using a back leg dynamometer. The results of this study indicate that the use of lifting straps led to an increase in isometric mid-thigh pull performance (p=0.001). Overall, the use of lifting straps was effective in enhancing isometric mid-thigh pull performance. In conclusion, the use of lifting straps significantly enhances pulling performance in exercise models, such as deadlifts and mid-thigh pulls, primarily by improving the grip on the bar, compensating for low grip strength, and alleviating fatigue in the gripping muscles. Strength and conditioning coaches may play a significant role in improving athletes' 1RM performance by incorporating the use of lifting straps, especially in pulling exercises involving high weights, according to athletes' training goals.

Relationship Between Stance Width Variation During One Repetition Maximum Barbell Hip Thrust Performance and Kicking Speed for Young Elite Silat Athletes

Study purpose. This study aimed to determine the relationship between kicking speed performance and different stance widths during barbell hip thrust (BHT) at one repetition maximum (1RM) scores among young elite Silat athletes. Materials and methods. 15 male and 15 female Silat athletes with at least one year of resistance training experience and a mean age of 21.3 ± 1.2 years participated in this study. The load indicator performance associated with kicking performance was measured using 1RM load during BHT at varying stance widths. The data was analyzed using Pearson correlation tests through the SPSS Version 25 application. Results. A significant correlation was found between stance width, physical characteristics, and performance metrics with a low to moderate relationship. For physical features, weight (r=0.43, p<.05), height (r= 0.64, p<.05), and leg length (r= 0.44, p<.05) show positive relationship. Low to moderate significant relationships were found during WSW-RFK (r=0.39, p<.05) regarding 1RM and kicking performance. No significant correlations were found between NSW or NRW and the observed variables, except for a negative correlation between NRW and strength (r= -0.43, p < .05). There was a significant difference between males vs. females in RFK-NSW, RFK (p=0.006, p< .05), and LFK-NRW (p=0.001, p< .05) in kicking performance. Conclusions. This study revealed that stance width in barbell hip thrusts moderately correlates with physical characteristics and performance in young elite Silat athletes, where wider stances align with physical characteristics and narrower stances align with lower kicking performance. It also highlighted the importance of personalized training due to observed gender differences in kicking speed.

The Effects of Power Training Frequency on Muscle Power and Functional Performance in Older Women: A Randomized Controlled Trial.

Katsoulis, K and Amara, CE. The effects of power training frequency on muscle power and functional performance in older women: a randomized controlled trial. J Strength Cond Res 37(11): 2289-2297, 2023-Low-intensity power training (PT) has emerged as an effective method for improving muscle power and functional performance in older adults. However, effects of low training frequencies are less understood and could expand the repertoire of exercise prescription, particularly in older women who experience greater functional disability with age compared with men. This study investigated the impact of frequency of low-intensity (40% of 1 repetition maximum, 1RM) PT on lower-body power and functional performance in healthy older women. Women (74 ± 4 years) were randomized to 12 weeks of PT of 1 (PT1, n = 14), 2 (PT2, n = 17), or 3 (PT3, n = 17) d·wk -1 or wait control (CON, n = 15). Measures included leg press 1RM, knee extension power (KEP), and functional performance (stair climb power, stair climb time, 30-second chair stands, 400-m walk, Short Physical Performance Battery). There were no differences between the frequency of training in changes in leg press 1RM, KEP, or functional performance after 12 weeks. Pre-post data for individual training groups revealed that leg press 1RM improved in all PT groups (20-33%, p < 0.05). Furthermore, KEP improved in PT2 and PT3 by 10 and 12%, respectively, and all PT groups improved in the 30-second chair stands and Short Physical Performance Battery (6-22%), whereas PT1 and PT3 improved in the 400-m walk and PT2 improved in stair climb power and stair climb time after training (4-7%, p < 0.05). One to 3 weekly low-intensity PT sessions can improve functional performance, although improvements in both functional performance and power might require 2 or 3 sessions per week in older healthy women.

Association Between Foundation Strength and Weightlifting Exercises in Highly Trained Weightlifters: Support for a General Strength Component.

Zecchin, A, Puggina, EF, Hortobágyi, T, and Granacher, U. Association between foundation strength and weightlifting exercises in highly trained weightlifters: support for a general strength component. J Strength Cond Res 37(7): 1375-1381, 2023-In addition to specific weightlifting exercises (i.e., clean and jerk and snatch), foundation strength exercises (i.e., overhead press, front squat, and deadlift) constitute an integral part of the weightlifters' training regime. The unexamined concept behind this training plan is that foundation strength exercises are associated with clean and jerk and snatch performance, implying the existence of a general strength component. We thus determined the relationship between performance in foundation strength exercises (overhead press, front squat, and deadlift) and weightlifting exercises (clean and jerk and snatch) in weightlifters. Well-trained weightlifters ( N = 19, age: 26.8 ± 4.4 years; body mass index: 27.6 ± 2.3 kg·m -2 ; and training history: 4.6 ± 0.8 years) performed 1 repetition maximum tests (1RM) in foundation strength and weightlifting exercises, over 14 days, in a randomized order. We observed significant correlations in 1RM performance between the overhead press and snatch ( r = 0.69), front squat and snatch ( r = 0.73), overhead press and clean and jerk ( r = 0.67), and front squat and clean and jerk ( r = 0.72, all r values: p < 0.01). No significant correlations were found for 1RM performance between the snatch and deadlift or between the clean and jerk and deadlift ( r- range: 0.20-0.58; p > 0.05). Stepwise linear regression revealed that 1RM performance in the overhead press and front squat explained 62% of the variance in snatch 1RM performance ( F = 5.51; p < 0.04). Overhead press and front squat 1RM performance explained 59% of the variance in the clean and jerk 1RM performance ( F = 5.14; p < 0.04). Our results demonstrate the existence of a general strength component between selected foundation strength exercises and weightlifting performance. However, the use of the front squat and overhead press to increase 1RM performance in weightlifting exercises needs to be determined in future research using a different methodological approach (i.e., longitudinal protocols), given that the observed correlations do not necessarily imply causation.

Reliability of kettlebell swing one and five repetition maximum.

Research into the kettlebell swing has increased in the last decade. There has been a paucity of literature assessing an individual's ability to perform the kettlebell swing exercise. The purpose of this study was to determine the test-retest reliability of the one and five repetition maximum (1RM and 5RM) kettlebell swing. Twenty four recreational resistance-trained participants performed an isometric mid-thigh pull (IMTP) and two familiarization sessions followed by three test sessions for each RM load approximately one week apart, using a custom-built plate-loaded kettlebell. On each test occasion, subjects completed a series of warm-up sets followed by 3-4 progressively heavier kettlebell swings to a standardized height until 1RM or 5RM was reached. Test-retest reliability was calculated using the intra-class correlation (ICC) and typical error was represented as the coefficient of variation (CV%) with 90% confidence limits (90% CL). The smallest worthwhile change (SWC%) representing the smallest change of practical importance, was calculated as 0.2 × between-subject standard deviation. The relationship of kettlebell swing performance and maximum strength was determined by Pearson correlation with ±90% CL between the absolute peak force recorded during IMTP and 1RM or 5RM. Results demonstrated a high test-retest reliability for both the 1RM (ICC = 0.97, 90% CL [0.95-0.99]; CV = 2.7%, 90% CL [2.2-3.7%]) and 5RM (ICC = 0.98, 90% CL [0.96-0.99]; CV = 2.4%, 90% CL [1.9-3.3%]), respectively. The CV% was lower than the SWC for both the 1RM (SWC = 2.8%, 90% CL [1.9-3.5]) and 5RM (SWC = 2.9%, 90% CL [1.9-3.6]) kettlebell swing. The correlation between IMTP absolute peak force and the 1RM (r = 0.69, 90% CL 0.43-0.83) was large and very large for the 5RM (r = 0.75, 90% CL [0.55-0.87]). These results demonstrate the stability of 1RM and 5RM kettlebell swing performance after two familiarization sessions. Practitioners can be confident that changes in kettlebell swing 1RM and 5RM performance of >3.6 kg represent a practically important difference, which is the upper limit of the 90% CL.

Correlation between Isometric Maximum Strength and One Repetition Maximum in the Calf Muscle in Extended and Bended Knee Joint

Previous research points out high relevance of maximal strength measurement in the diagnostics of different populations. However, there is inconsistency in procedures of maximum strength measurements. Thus, it must be questioned whether the results from different studies are actually comparable. Due to the aforementioned problems in standardization, the aim of this study was to assess correlations between and reproducibility of isometric and dynamic strength testing. Since there are many studies investigating maximal strength in the calf muscles, this study will examine the plantar flexors. For this purpose, 87 active participants were recruited (m: 52, f: 35, age: 28.3 ± 5.5 years, range 18-38 years, height: 178.3 ± 6.6 cm, weight: 81.5 ± 7.4 kg) who performed maximal isometric strength testing and dynamic 1RM testing in plantar flexion both with extended and bended knee joint. Pearson correlation as well as concordance correlation coefficient (CCC) were determined. In literature, CCC is used to determine reproducibility between two different testing methods. There were correlation coefficients of r = 0.63 – 0.77 and &lt;i&gt;ρ&lt;sub&gt;c&lt;/sub&gt;&lt;/i&gt;=0.62 ‒ 0.77. Results are comparable with correlations between maximal isometric strength and 1-RM in previous studies in different movements. In consideration of CCC, isometric strength testing and 1RM seem to not measure the same parameter, therefore comparison of results measured with different procedures seems difficult. Our results exhibit a high influence of isometric maximal strength on 1RM performance. However, 1RM tests cannot be replaced by isometric strength testing. Care must be taken due to standardization of procedure when comparing results from different studies and, especially, if 1RM testing should be replaced with isometric strength measurement.

Associations between maximal strength, sprint, and jump height and match physical performance in high-level female football players.

Studies on females' decisive physical components to physical match-play performance are sparse and only emphasize endurance tests. Thus, the influence of maximal strength and power on physical performance during match-play is currently unknown. The aim of this study was to assess the association between one repetition maximum (1RM) half squat strength, 5-, 10-, and 15-m sprint times, countermovement jump (CMJ) height, and physical high-intensity match-play performance in high-level female football players. Thirty-seven female high-level football players completed 1-2 football matches with physical performance measured by local positioning tracking. Correlations were assessed between physical match-play performance variables (total distance covered, running distance, high-intensity running distance, sprinting distance as well as acceleration and deceleration counts, and peak speed) and laboratory tests (half squat 1RM, 15-m sprint, and CMJ). We found no correlation between 1RM and physical match-play performance. Further, 10-m- and 15-m sprint time (r=-0.56, r=-0.56, p<0.001) and CMJ jump height (r=0.50, p<0.01) strongly correlated with peak match speed. Further, there was a moderate correlation between 15-m sprint time and ACC (r=-0.43, p<0.05). 5-m sprint time did not correlate with physical match-play performance. Laboratory-based sprint and jump performance, but not maximal half squat strength, showed moderate to large correlations with high-intensity physical match-play performance measures in high-level female football players.

Resistance training intervention performed with different muscle action durations influences the maximal dynamic strength without promoting joint-angle specific strength gains

ABSTRACT The present study investigated the effect of 10-week matched (range of motion, volume, intensity, rest, and repetition duration) training protocols with varying muscle action duration (MAD) on maximal voluntary isometric contraction (MVIC) test at eight different knee angles and one-repetition maximum (1RM) test after in seated knee extensor machine. Forty women were allocated into one control and three training groups with varying MAD: 5C1E (5s concentric action [CON] and 1s eccentric action [ECC]), 3C3E (3s CON and 3s ECC), and 1C5E (1s CON and 5s ECC). All training groups (5C1E, 3C3E, and 1C5E) showed a greater relative response in 1RM performance than the control group (0.1 ± 3.5%, p ≤ 0.05). The 1C5E group presented greater relative increases in the 1RM performance (22.1 ± 11.6%) compared to 5C1E (13.6 ± 9.2%; p ≤ 0.05) and 3C3E (14.1 ± 5.5%, p ≤ 0.05) groups. The training groups increased the MVIC performance more than the control group (p ≤ 0.05), although there were no significant differences between the training groups. This study demonstrated that isoinertial resistance training protocols with shorter CON MAD showed greater maximum dynamic strength performance response than matched training protocols with other MAD configurations. However, the configuration of MAD did not induce angle-specificity to increase the maximum isometric strength.

Is there a relationship between the overhead press and split jerk maximum performance? Influence of sex

The aims of this study were to (I) determine the differences and relationship between the overhead press and split jerk performance in athletes involved in weightlifting training, and (II) explore the magnitude of these differences in one-repetition maximum (1RM) performances between sexes. Sixty-one men (age: 30.4 ± 6.7 years; height: 1.8 ± 0.5 m; body mass 82.5 ± 8.5 kg; weightlifting training experience: 3.7 ± 3.5 yrs) and 21 women (age: 29.5 ± 5.2 yrs; height: 1.7 ± 0.5 m; body mass: 62.6 ± 5.7 kg; weightlifting training experience: 3.0 ± 1.5 yrs) participated. The 1RM performance of the overhead press and split jerk were assessed for all participants, with the overhead press assessed on two occasions to determine between-session reliability. The intraclass correlation coefficients (ICC) and 95% confidence intervals showed a high reliability for the overhead press ICC = 0.98 (0.97 – 0.99). A very strong correlation and significant differences were found between the overhead press and split jerk 1RM performances for all participants (r = 0.90 [0.93 – 0.85], 60.2 ± 18.3 kg, 95.7 ± 29.3 kg, p ≤ 0.001). Men demonstrated stronger correlations between the overhead press and split jerk 1RM performances (r = 0.83 [0.73-0.90], p ≤ 0.001) compared with women (r = 0.56 [0.17-0.80], p = 0.008). These results provide evidence that 1RM performance of the overhead press and split jerk performance are highly related, highlighting the importance of upper-limb strength in the split jerk maximum performance.

Predictive Validity of the Snatch Pull Force-Velocity Profile to Determine the Snatch One Repetition-Maximum in Male and Female Elite Weightlifters.

Background: The prediction of one repetition-maximum (1RM) performance from specific tests is highly relevant for the monitoring of training in weightlifting. Therefore, this study aimed at examining the predictive validity of the theoretical 1RM snatch (snatchth) computed from the two-point snatch pull force-velocity relationship (FvR2) to determine actual snatch 1RM performance in elite weightlifters. Methods: Eight (three female, five male) elite weightlifters carried out a 1RM snatch test followed by a snatch pull test with loads of 80% and 110% of the previously determined 1RM snatch. Barbell kinematics were determined for all lifts using video-tracking. From the snatch pull barbell kinematics, the snatch pull FvR2 was modeled and the snatchth was calculated. Results: The main findings indicated a non-significant (p = 0.706) and trivial (d = 0.01) mean difference between the actual 1RM snatch performance and the snatchth. Both measures showed an extremely large correlation (r = 0.99). The prediction accuracy of the actual 1RM snatch from snatchth was 0.2 ± 1.5 kg (systematic bias ± standard deviation of differences). Conclusions: This study provides a new approach to estimate 1RM snatch performance in elite weightlifters using the snatch pull FvR2. The results demonstrate that the snatchth-model accurately predicts 1RM snatch performance.

Effects of Augmented Eccentric Load Bench Press Training on One Repetition Maximum Performance and Electromyographic Activity in Trained Powerlifters.

Montalvo, S, Gruber, LD, Gonzalez, MP, Dietze-Hermosa, MS, and Dorgo, S. Effects of augmented eccentric load bench press training on one repetition maximum performance and electromyographic activity in trained powerlifters. J Strength Cond Res 35(6): 1512-1519, 2021-Augmented eccentric load (AEL) training has been shown to elicit greater lower-body muscular strength increases and faster performance improvements compared with traditional strength training. However, it is unknown whether AEL training could provide similar improvements in upper-body muscular strength. Therefore, this study investigated the effects of a 4-week AEL training program on bench press one repetition maximum (1RM) strength, bar kinetics and kinematics, and surface electromyography (EMG) activity. Eight competitive powerlifters completed 5 training sessions consisting of 7 sets of a single repetition with up to 5 minutes rest between sets. Each session was completed at a predetermined AEL percentage consisting of 90% 1RM for concentric and supramaximal loads ranging from 105 to 125% 1RM during the eccentric phase with the use of eccentric hooks. After 4 weeks of AEL training, 1RM performance significantly increased from pretest to posttest (116.62 ± 27.48-124.28 ± 26.96 kg, p = 0.001). In addition, EMG amplitude of the pectoralis major decreased during the 125% AEL session to 59.86 ± 15.36% of pretest 1RM EMG values (p = 0.049, effect sizes [ESs] = 0.69). Furthermore, peak power of 1RM increased by 36.67% from pretest to posttest (p = 0.036, ES = 0.58). These study findings suggest that incorporating AEL bench press training into a 4-week training cycle may be a novel strategy to improve 1RM performance in competitive powerlifters in a short period.

Resistance training with different repetition duration to failure: effect on hypertrophy, strength and muscle activation.

BackgroundThis study investigated the effects of two 14-week resistance training protocols with different repetition duration (RD) performed to muscle failure (MF) on gains in strength and muscle hypertrophy as well as on normalized electromyographic (EMG) amplitude and force-angle relationships.MethodsThe left and right legs of ten untrained males were assigned to either one of the two protocols (2-s or 6-s RD) incorporating unilateral knee extension exercise. Both protocols were performed with 3–4 sets, 50–60% of the one-repetition maximum (1RM), and 3 min rest. Rectus femoris and vastus lateralis cross-sectional areas (CSA), maximal voluntary isometric contraction (MVIC) at 30o and 90o of knee flexion and 1RM performance were assessed before and after the training period. In addition, normalized EMG amplitude-angle and force-angle relationships were assessed in the 6th and 39th experimental sessions.ResultsThe 6-s RD protocol induced larger gains in MVIC at 30o of knee angle measurement than the 2-s RD protocol. Increases in MVIC at 90o of knee angle, 1RM, rectus femoris and vastus lateralis CSA were not significant between the 2-s and 6-s RD protocols. Moreover, different normalized EMG amplitude-angle and force-angle values were detected between protocols over most of the angles analyzed.ConclusionPerforming longer RD could be a more appropriate strategy to provide greater gains in isometric maximal muscle strength at shortened knee positions. However, similar maximum dynamic strength and muscle hypertrophy gains would be provided by protocols with different RD.

Does Sex Impact the Differences and Relationships in the One Repetition Maximum Performance Across Weightlifting Overhead Pressing Exercises?

Soriano, MA, García-Ramos, A, Calderbank, J, Marín, PJ, Sainz de Baranda, P, and Comfort, P. Does sex impact the differences and relationships in the one repetition maximum performance across weightlifting overhead pressing exercises? J Strength Cond 36(7): 1930-1935, 2022-This study aimed to determine the impact of sex on the differences and relationships of the one repetition maximum (1RM) performance between 3 overhead pressing exercises (push press [PP], push jerk [PJ] and split jerk [SJ]). 15 men (body mass [BM]: 82.3 ± 9.9 kg; weightlifting training experience: 2.6 ± 1.6 years) and 15 women (BM: 64.4 ± 7.0 kg; weightlifting training experience: 2.2 ± 1.4 years) participated in this study. A ratio-scaled (1RM·BM-1) was used for the comparison between them. The 1RM of the 3 exercises were evaluated within the same testing session using a combined 1RM assessment method. The interaction effect of exercise and sex did not reach statistical significance (p = 0.671; η2 = 0.001). In contrast, there were significant main effects of exercise (p ≤ 0.01) and sex (p < 0.001) with medium (η2 = 0.096) and large effect sizes (η2 = 0.306), respectively. A similar main effect of exercise was reported for both men (PP [1.0 ± 0.1 kg·kg-1] < PJ [1.1 ± 0.2 kg·kg-1] ∼ SJ [1.2 ± 0.2 kg·kg-1]) and women (PP [0.8 ± 0.1 kg·kg-1] < PJ [0.9 ± 0.2 kg·kg-1] ∼ SJ [0.9 ± 0.2 kg·kg-1]). The 1RM performance of the 3 exercises was significantly correlated for men (r [range] = 0.856-0.963) and women (r [range] = 0.636-0.925). Sex does not affect the differences in the 1RM performance across weightlifting overhead pressing exercises. However, stronger correlations and lower variation in the 1RM performance during the PP, PJ, and SJ are expected for men compared with women.

Validity and Reliability of the Isometric Prone Bench Pull Test.

Isometric strength tests are gaining popularity in recent years. However, no study has validated any isometric strength tests to assess upper body pulling ability. The aim of this study was to investigate the validity and reliability of isometric prone bench pull. Twenty-three resistance trained athletes (age: 26±4 years, height: 1.75±0.07 m, body mass: 78.6±11.5 kg) were required to perform prone bench pull 1 repetition maximum and isometric prone bench pull tests during the familiarization and actual testing sessions. Isometric prone bench pull was performed at 90° and 120° elbow angles. Peak force and rate of force development measures were highly reliable with intra-correlation coefficient between 0.881-0.987. Peak force obtained from isometric prone bench pull at both elbow angles showed large correlations to prone bench pull 1 repetition maximum (r=0.833-0.858, p<0.01). Linear regression equations to predict 1RM performance from isometric prone bench pull peak force produced an estimated 1RM with a standard error of only 3-6% of the average prone bench pull 1 repetition maximum. The current findings show that isometric prone bench pull is a reliable test and can be used to predict prone bench pull performance.

The effect of resistance training, detraining and retraining on muscle strength and power, myofibre size, satellite cells and myonuclei in older men.

Ageing is associated with an attenuated hypertrophic response to resistance training and periods of training interruptions. Hence, elderly would benefit from the 'muscle memory' effects of resistance training on muscle strength and mass during detraining and retraining. As the underlying mechanisms are not yet clear, this study investigated the role of myonuclei during training, detraining and retraining by using PCM1 labelling in muscle cross-sections of six older men. Knee extension strength and power were measured in 30 older men and 10 controls before and after 12 weeks resistance training and after detraining and retraining of similar length. In a subset, muscle biopsies from the vastus lateralis were taken for analysis of fibre size, fibre type distribution, Pax7+ satellite cell number and myonuclear domain size. Resistance training increased knee extension strength and power parameters (+10 to +36%, p<.001) and decreased the frequency of type IIax fibres by half (from 20 to 10%, p=.034). Detraining resulted in a modest loss of strength and power (-5 to -15%, p≤.004) and a trend towards a fibre-type specific decrease in type II fibre cross-sectional area (-17%, p=.087), type II satellite cell number (-30%, p=.054) and type II myonuclear number (-12%, p=.084). Less than eight weeks of retraining were needed to reach the post-training level of one-repetition maximum strength. Twelve weeks of retraining were associated with type II fibre hypertrophy (+29%, p=.050), which also promoted an increase in the number of satellite cells (+72%, p=.036) and myonuclei (+13%, p=.048) in type II fibres. Changes in the type II fibre cross-sectional area were positively correlated with changes in the myonuclear number (Pearson's r between 0.40 and 0.73), resulting in a stable myonuclear domain. Gained strength and power and fibre type changes were partially preserved following 12 weeks of detraining, allowing for a fast recovery of the 1RM performance following retraining. Myonuclear number tended to follow individual changes in type II fibre size, which is in support of the myonuclear domain theory.

Effects of Hypohydration on Muscular Strength, Endurance, and Power in Women.

Gann, JJ, Andre, TL, Gallucci, AR, and Willoughby, DS. Effects of hypohydration on muscular strength, endurance, and power in women. J Strength Cond Res 35(2S): S102-S106, 2021-The purpose of this study was to determine the effects of dehydration on muscular strength, endurance, power, and perceptual measures in resistance-trained women. Ten resistance-trained women completed 2 bouts of exercise (1 repetition maximum [1RM] for bench press and angled leg press followed by 5 sets to failure of 75% of 1RM and vertical jump), either dehydrated (∼3% body mass) (DT) or heat-exposed with fluid replacement (HT). Paired t-tests revealed bench press 1RM was significantly lower for DT (42.7 ± 14.5 kg) compared with HT (44.1 ± 13.9 kg). No significant difference was found for leg press 1RM (DT = 216.1 ± 55.0 kg; HT = 223.4 ± 55.7 kg). There was also no difference in total reps completed for bench press (DT = 33.5 ± 5.0; HT = 33.0 ± 5.5) or leg press (DT = 42.6 ± 20.3; HT = 45.8 ± 19.7). There was no significant difference for vertical jump height (DT: 45.8 ± 5.2 cm, HT: 46.9 ± 6.0 cm). Ratings of perceived exertion (RPE) and session RPE were not significantly different between trials. Significant differences for perceived recovery status (DT: 5.1 ± 2.2, HT: 7.2 ± 1.1) and perceived readiness (DT: 4.2 ± 1.0, HT: 2.5 ± 0.5) indicate subjects expected impaired performance during DT. The current results suggest that previous night dehydration may have a negative impact on both bench press 1RM performance and perceptual feelings of recovery in resistance-trained women.