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Abstract

The purpose of this study was to compare average concentric velocity (ACV) and rating of perceived exertion (RPE) based on repetitions in reserve on the squat, bench press and deadlift. Fifteen powerlifters (3 female, 12 male, 28.4 ± 8.5 years) worked up to a one repetition maximum (1RM) on each lift. RPE was recorded on all sets and ACV was recorded for all sets performed at 80% of estimated 1RM and higher, up to 1RM. RPE at 1RM on the squat, bench press and deadlift was 9.6 ± 0.5, 9.7 ± 0.4 and 9.6 ± 0.5, respectively and were not significantly different (p > 0.05). ACV at 1RM on the squat, bench press and deadlift was 0.23 ± 0.05, 0.10 ± 0.04 and 0.14 ± 0.05 m·s-1, respectively. The squat was faster than both the bench press and deadlift (p <0.001) and the deadlift was faster than the bench press (p = 0.05). Very strong relationships (r = 0.88 to 0.91) between percentage 1RM and RPE were observed on each lift. ACV showed strong (r= -0.79 to -0.87) and very strong (r= -0.90-92) inverse relationships with RPE and percentage 1RM on each lift, respectively. We conclude that RPE may be a useful tool for prescribing intensity for the squat, bench press, and deadlift in powerlifters, in addition to traditional methods such as percentage of 1RM. Despite high correlations between percentage 1RM and ACV, a 'velocity load profile' should be developed to prescribe intensity on an individual basis with appropriate accuracy.
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... Due to these limitations of the submaximal repetitions to fatigue method for estimating 1RM, others have sought to utilize load-velocity profiles. Previous findings have demonstrated a strong linear relationship (R 2 ≥ 0.9) between 1RM and average concentric velocity (ACV) [21][22][23], with early investigations suggesting ACV at 1RM is relatively stable [22,24,25]. Conversely, more recent investigations have brought into question the validity of this method due to the large variation in ACV at an athlete's 1RM [16]. ...
... Due to the inclusion of three protocols, there were six possible sequences in which participants could complete the investigation (i.e., P1-P2-SS, P1-SS-P2, P2-P1-SS, P2-SS-P1, SS-P1-P2, and SS-P2-P1). With the current sample size (24) and subgroups (12 males and 12 females), each sequence was represented four times in total and twice within each sub-group. The order in which the sequences were assigned to participants was determined using a randomized permuted block design function within the random R package [41]. ...
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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.
... Mean velocity refers to the average concentric movement velocity, and peak velocity refers to the maximum instantaneous velocity reached during the concentric phase of the movement [3,4]. In the context of powerlifting exercises, mean velocity is usually the variable of choice [5]. This is due to mean velocity being more reliable compared to peak velocity [6][7][8]. ...
... Because the average concentric velocity decreases gradually with higher percentages of the one repetition maximum (1RM) [5], a gradual loading protocol was selected to encompass a broader spectrum of velocities. A further benefit of a gradual loading protocol is that sticking points and other changes to barbell kinematics might only become apparent closer to muscular failure [23,24]. ...
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The aim of this study was to determine the validity of three smartphone applications measuring barbell movement velocity in resistance training and comparing them to a commercially available linear transducer. Twenty competitive powerlifters (14 male and 6 female) completed a progressive loading protocol in the squat, bench press and deadlift (sumo or conventional) until reaching 90% of the highest load they had achieved in a recent competition. Mean velocity was concurrently recorded with three smartphone applications: Qwik VBT (QW), Metric VBT (MT), MyLift (ML), and one linear transducer: RepOne (RO). 3D motion capturing (Vicon) was used to calculate specific gold standard trajectory references for the different systems. A total of 589 repetitions were recorded with a mean velocity of (mean ± standard deviation [min-max]) 0.44 ± 0.17 [0.11–1.04] m·s⁻¹, of which MT and ML failed to identify 52 and 175 repetitions, respectively. When compared to Vicon, RO and QW consistently delivered valid measurements (standardized mean bias [SMB] = 0 to 0.21, root mean squared error [RMSE] = 0.01 to 0.04m·s⁻¹). MT and ML failed to deliver a level of validity comparable to RO (SMB = -0.28 to 0.14, RMSE = 0.04–0.14m·s⁻¹), except for MT in the bench press (SMB = 0.07, RMSE = 0.04m·s⁻¹). In conclusion, smartphone applications can be as valid as a linear transducer when assessing mean concentric barbell velocity. Out of the smartphone applications included in this investigation, QW delivered the best results.
... Therefore, researchers explored how to leverage objective barbell velocity data to estimate repetitions-in-reserve given that velocity loss was associated with metabolite accumulation in muscles (i.e., a proxy of fatigue). Indeed, it has been shown that the loss of movement velocity during a set is related to the (perceived) number of repetitions-in-reserve (41,66,100). Therefore, it should follow that monitoring velocity data to regulate the number of repetitions-in-reserve, and thus training set volume, should also be effective for improving strength-related adaptations given its potential to regulate the volume of training. ...
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Hirsch, SM, Chapman, CJ, Singh, H, Baker, DG, and Frost, DM. A critical appraisal of using barbell velocity data to regulate training. J Strength Cond Res 39(3): 360-372, 2025-Practitioners must balance numerous training variables to ensure they do not impose too much nor too little training stress on their athlete. As an athlete's capacity can fluctuate based on their preparedness for training, the intended vs. actual training intensity in a fixed training program may not coincide. Similarly, the training set volume that an athlete should be exposed to may fluctuate depending on their current state. A discrepancy between intended vs. actual training intensity and volume could negatively impact subsequent training adaptations. Thus, researchers and practitioners have advocated for "autoregulation," whereby the volume and intensity of training are automatically adjusted based on the athlete's preparedness. One proposed method of autoregulating resistance training is by using barbell velocity data. However, it is unclear whether, and under which contexts, these data are appropriate for regulating resistance training. Therefore, the purpose of this literature review was to critically examine the current research on using barbell velocity data to regulate resistance training intensity and volume. After examining the relevant literature, it is the authors' belief that the current data do not support using velocity data to precisely regulate resistance training intensity. However, it is the authors' belief that the current literature does suggest that researchers and practitioners can leverage these data to regulate other aspects of resistance training, such as athlete motivation, autonomy, and focus of attention, which could also impact the resulting adaptations from training. Overall, more research is required to better understand how researchers and practitioners should use velocity data to guide training.
... Research consistently shows a linear relationship between relative load and movement velocity across resistance exercises, enabling precise predictions and monitoring of training intensity [12,13]. However, individualized approaches are essential, as velocity profiles can vary between athletes due to differences in physiological characteristics and technical execution [14][15][16][17]. ...
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Citation: González-Alcázar, F.J.; Jiménez-Martínez, P.; Alix-Fages, C.; Ruiz-Ariza, A.; Casuso, R.A.; Varela-Goicoechea, J.; García-Ramos, A.; Jerez-Martínez, A. Impact of Low-Load High-Volume Initial Sets vs. Traditional High-Load Low-Volume Bench Press Protocols on Functional and Structural Adaptations in Powerlifters. Appl. Sci. 2025, 15, 1974. Abstract: This study aimed to investigate the effectiveness of low-load high-volume (LL-HV) resistance training compared to traditional high-load low-volume (HL-LV) protocols in eliciting functional and structural adaptations in powerlifters. Twenty-six well-trained male powerlifters were randomly assigned to LL-HV and HL-LV groups and participated in a 12-week supervised training intervention. The LL-HV protocol involved an initial bench press set performed at 45-60% of one-repetition maximum (1RM), with very high repetitions, while the HL-LV group performed the initial set at 75-90% of 1RM, following matched total training volume for accessory exercises. Both groups trained twice weekly, with identical proximity to failure based on repetitions in reserve (RIR). Functional outcomes included changes in bench press 1RM and mean velocity (MV) measured at various submaximal loads, while structural adaptations were assessed through arm and chest circumferences. Statistical analyses were conducted using a two-factor mixed analysis of variance (ANOVA) to assess the effects of "time" and "training group" on these outcomes. Percent changes were comparable between groups for most variables, with significant improvements observed in the LL-HV group for MV at 80% of 1RM and arm circumference. These findings suggest that LL-HV, emphasizing high-repetition sets, offers an effective alternative to HL-LV protocols for enhancing performance and structural adaptations in powerlifters.
... An emerging theme when dissecting the current load and volume autoregulation literature is that each autoregulation method has different advantages and limitations; thus, an integrated approach may be plausible to maximize the advantages and minimize the limitations. Although the concept of integrating some of these profiles and relationships for RT prescription is not new (García Ramos 2023; Pareja-Blanco and Loturco 2022; González-Badillo et al. 2022;Weakley et al. 2020;Banyard et al. 2020;Helms et al. 2016Helms et al. , 2017, to our knowledge, we are unaware of a single model integrating all of these concepts; therefore, synthesizing a conceptually integrated model may be a potential avenue to explore in future directions and contextualize for practical applications as implied by Hickmott et al. (2022). We Content courtesy of Springer Nature, terms of use apply. ...
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Resistance training (RT) load and volume are considered crucial variables to appropriately prescribe and manage for eliciting the targeted acute responses (i.e., minimizing neuromuscular fatigue) and chronic adaptations (i.e., maximizing neuromuscular adaptations). In traditional RT contexts, load and volume are generally pre-prescribed; thereby, potentially yielding sub-optimal outcomes. A RT concept that individualizes programming is autoregulation: a systematic two-step feedback process involving, (1) monitoring performance and its constituents (fitness, fatigue, and readiness) across multiple time frames (short-, moderate-, and long-term); and (2) adjusting programming (i.e., load and volume) to elicit the targeted goals (i.e., responses and adaptations). A growing body of load and volume autoregulation research has accelerated recently, with several meta-analyses suggesting that autoregulation may provide a small advantage over traditional RT. Nonetheless, the existing literature has typically conceptualized these current autoregulation methods as standalone practices, which has limited their extensive utility in research and applied settings. The primary purpose of this review was three-fold. Initially, we synthesized the current methods of load and volume autoregulation, while disseminating each method’s main advantages and limitations. Second, we conceptualized a theoretical Integrated Velocity Model (IVM) that integrates the current methods for a more holistic perspective of autoregulation that may potentially augment its benefits. Lastly, we illustrated how the IVM may be compared to the current methods for future directions and how it may be implemented for practical applications. We hope that this review assists to contextualize a novel autoregulation framework to help inform future investigations for researchers and practices for RT professionals.
... RPE may also be based on perceived bar speed, meaning that the coach will watch the lift in real time or on video or the client will watch their own video and rate how fast the barbell moved through the lift (Helms et al. 2017). Some coaches will get as granular as clipping videos to compare the length in seconds of how long sets or lifts took. ...
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The perspectives of skilled experts who help learners develop and improve bodily skills has not often been examined in sociology. In this paper, I focus on the role of selective sensory engagement with moving bodies as an important way of knowing through which skilled experts assess and intervene upon the skill acquisition of learners. I bring together literature on body pedagogics with literature on sociology of the senses to understand how embodied, sensorial knowledge is an inter-corporeal and intersubjective resource for the transmission of bodily skills. I use interviews with barbell coaches and yoga teachers in the United States to understand the processes by which these skilled experts construct ‘good form’ and its normative limits and I outline three interrelated processes of sensorial knowing through which barbell coaches and yoga teachers help their paying clients achieve ‘good form’ when learning to engage in these fitness cultures. I argue that that the use and training of the senses in body pedagogics is an understudied but essential way of knowing to understand the transmission and embodiment of culture.
... In addition, it has shown excellent test-retest reliability in our laboratory (ICC (3,1) = 0.932; SEM = 0.019; MD = 0.054; n = 12). The device was used according to manufacturer's instructions such that the device was attached to the barbell with a perpendicular angle being achieved throughout the entirety of lifts (23). Although some participants completed their trials in the morning and some in the evening, each participant completed all trails within 2 hours of the same time of day. ...
... Several factors may have influenced the present study results that do not agree with the tendencies reported in previous studies [5,16,22,39]. First, the participants in the present study were a relatively heterogeneous group compared to previous studies examining homogeneous groups such as trained [12,19] and elderly [25]. Indeed, the relationship between the velocity recorded during a single repetition and the %1RM may be influenced by the execution technique and sex [41]. ...
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Purpose This study aims to evaluate the accuracy of predicting one-repetition-maximum (1RM) using the load-velocity relationship and different repetition-to-failure estimation equations for ten lower-extremity exercises. Methods A total of 22 healthy participants were recruited. The tested exercises included ankle, knee, and hip joint flexion and extension, as well as hip abduction, hip adduction, and leg press. Velocity during the concentric phase was measured using a linear transducer, and individual linear regression models were established using incremental submaximal loads (40–80% 1RM) and velocity to estimate the 1RM. Repetition-to-failure estimations of 1 RM were assessed with eleven different regression equations, among them the Lombardi equation. Intraclass correlation coefficient (ICC), Bland and Altman plots, and normalized mean absolute error (NMAE) were used to compare the estimations with a measured 1RM. Results Predictions based on the load-velocity relationship exhibited NMAE values ranging from 8.6% to 35.2%, ICC values from 0.35 to 0.87, and substantial limits of agreement across all exercises, in contrast to the measured 1RM values. Among the fatigue estimation equations, the Lombardi equation demonstrated the lowest NMAE across all exercises (5.8%), with an excellent ICC of 0.99 and narrow limits of agreement. Conclusion The load-velocity relationship proved inadequate for predicting 1RM in lower-extremity single-joint exercises. However, the Lombardi estimation equations showcased favorable predictive performance with a consistently low average NMAE across all exercises studied.
Conference Paper
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