PURPOSE:Lifting straps (LS) are popular tools used by resistance-training (RT) practitioners with the intention of improving exercise performance. This tool is worn around the wrist to enhance grip on the barbell or other RT equipment and potentially decrease grip limitation throughout the exercise-a limitation that is usually reported by practitioners, especially during deadlifts, weightlifting movements, and pulling exercises. However, this knowledge remains mostly based on common experiential beliefs. Thus, this narrative review aims to highlight the current knowledge on the impact of LS in RT, focusing on physiological and biomechanical effects, exercise performance, chronic training adaptations, and safety concerns, and also to expose the existing literature gaps and distinguish between evidence-based findings and empirical assumptions. CONCLUSION:Evidence suggests that LS can enhance maximal strength and grip perception. However, for pulling/back exercises, no consistent effects have been observed. In addition, LS may increase mechanical work in the deadlift, but contrary to common belief, they appear not to contribute to increased muscle recruitment. Furthermore, no scientific evidence supports the chronic effects of LS usage in training; it is still a hypothesis. Finally, this review offers future research insights to assist sport scientists in designing and conducting more comprehensive investigations on this topic, ultimately enhancing the understanding and application of LS in RT.

Objectives:The integration of stroboscopic eyewear into sport-specific warm-ups has demonstrated potential for enhancing performance. This study investigated the immediate effects of stroboscopic stimulation on sport-specific performance in padel, focusing on volley accuracy and reactive agility. Methods:Twenty competitive male padel players (26.0 ± 6.3 years) completed two experimental sessions in a counterbalanced within-subjects design: one involving a warm-up with stroboscopic eyewear (5 Hz, 50% duty cycle) and another under normal visual conditions. Performance was evaluated during and after the warm-up in each condition using a volley accuracy task, and a light-based reactive agility test was assessed after the warm-up. Results:Volley accuracy performance was significantly reduced under stroboscopic conditions compared to control conditions (p < 0.001, d = 3.14). However, volley performance significantly improved after the stroboscopic warm-up compared to the control post-warm-up (p = 0.041, d = 0.52). No statistically significant differences were found for reactive agility (p = 0.092), though a small-to-moderate effect size favored the stroboscopic condition (d = 0.41). Conclusions:A single warm-up session using stroboscopic stimulation can acutely enhance volley accuracy in padel once normal vision is restored, suggesting potential for perceptual-motor priming. Effects on reactive agility were inconclusive, potentially due to task specificity and stimulus limitations. These insights may help coaches boost performance by integrating this approach into pre-training and pre-competition routines.

This study investigated how varying body positions (seated, prone, supine) and knee joint angles (90 degrees, 120 degrees, 150 degrees) influence the bilateral deficit (BD) in isometric hamstring strength. Thirty physically active participants (15 males, 15 females) performed unilateral and bilateral maximal voluntary isometric contractions (MVICs) across the tested position & times; angle conditions. Peak force (Fmax) and rate of force development (RFD) measures (RFDmax, RFD50 ms, and RFD200 ms) were recorded. Results indicated that the seated position elicited a greater bilateral deficit (i.e., lower BD ratios) than the prone and supine positions, with differences that were more pronounced at more extended knee angles. These findings underscore the importance of considering position- and angle-specific influences when assessing BD in hamstring strength. Clinicians and researchers should standardize testing protocols to ensure accurate evaluation and data interpretation. From an applied standpoint, the results support the development of resistance-training strategies aimed at enhancing hamstring function at long muscle lengths-an approach relevant to both performance optimization and injury prevention.

ABSTRACT:Jaén-Carrillo, D, Cartón-Llorente, A, García-Ramos, A, and Santos, L. Mechanical variables derived from submaximal back squat performance are positively associated with running performance in highly trained endurance athletes. J Strength Cond Res 40(7): 799-806, 2026-The purpose of this study was to determine the relationship between lower-body maximal neuromuscular capacities and endurance running performance. Fifteen highly trained endurance runners completed 3 sessions. The first determined one-repetition maximum (1RM) in the half squat. The second assessed maximal neuromuscular capacities ( L0 : maximal theoretical load; V0 : maximal theoretical velocity; Aline : area under the load-velocity relationship line, used as a proxy for maximal power) and strength deficit (mean propulsive velocity [MPV] at 40-90% 1RM). The third measured running speed, ground contact time, cadence, and leg stiffness during 9- and 3-minute time trials. Pearson correlation analyses, with the significance level set at p < 0.05, revealed a positive association between Aline and leg stiffness during both the 9-minute ( r = 0.552, p = 0.033) and 3-minute ( r = 0.580, p = 0.023) time trials. In addition, leg stiffness was also significantly associated with strength deficit, showing moderate correlations with MPV at 60% 1RM ( r = 0.585, p = 0.022) and 70% 1RM ( r = 0.555, p = 0.032) in the 9-minute trial, and at 50% 1RM ( r = 0.611, p = 0.016), 60% 1RM ( r = 0.685, p = 0.005), 70% 1RM ( r = 0.653, p = 0.008), and 80% 1RM ( r = 0.552, p = 0.033) in the 3-minute trial. Given the established association between leg stiffness and running efficiency, long-distance runners may benefit from incorporating explosive strength training with moderate to high loads (50-80% 1RM) to enhance power output and maintain propulsive force during endurance running.

Velocity-based training (VBT) is well established for prescribing and monitoring intensity in traditional constant resistance training; however, its applicability to chain-based variable resistance training has not been examined. This study examined how different magnitudes of chain-based variable resistance influence commonly used VBT-derived metrics. Thirty-four resistance-trained men (age: 20.50 ± 2.00 years, constant-load one-repetition maximum [1RM]: 1.85 ± 0.22 × body mass) performed Smith machine back squats under three loading configurations (0

ABSTRACT:Huang, Y, García-Ramos, A, Chen, Z, Li, Z, Yu, J, Geng, Y, Li, D, Jia, B, and LAM, W-K. The effect of weightlifting belt on the relative load-velocity relationship and one-repetition maximum prediction accuracy in the free-weight back squat. J Strength Cond Res XX(X): 000-000, 2026-This study compared the relative load-velocity relationship between free-weight back squats performed with (SWB) and without (SNB) wearing a weightlifting belt, and examined the accuracy of the absolute load-velocity relationship to estimate SWB one-repetition maximum (1RM). Twenty-five resistance-trained athletes (14 men and 11 women) completed 2 sessions in both SWB and SNB conditions. The load-velocity relationship, modeled using both multiple-point (40, 55, 70, and 85% 1RM) and 2-point (40%, 85% 1RM) methods, was used to estimate SWB 1RM of the second session based on individual and average optimal minimum velocity thresholds from the first session. SWB significantly increased 1RM (119.2 ± 36.8 vs. 114.0 ± 34.9 kg; p < 0.001) and bar velocities across all 4 submaximal absolute loads ( p = 0.006-0.026), but slightly reduced velocities at relative loads of 85-100% 1RM ( p = 0.025-0.049). The velocities corresponding to different %1RM demonstrated acceptable reproducibility (mean coefficient of variation = 5.2%, mean intraclass correlation coefficient = 0.85) and no significant differences between the multiple- and 2-point methods ( p = 0.111-0.944). All approaches estimated SWB 1RM with low to moderate absolute percentage errors (4.2-5.2%). In conclusion, using a weightlifting belt does not substantially affect the %1RM-V relationship below 85%1RM and yields 1RM estimations with accuracy comparable with that previously reported for the SNB condition. The 2-point method combined with an optimal minimum velocity threshold provides a time-efficient approach for estimating 1RM and establishing the associated %1RM-V relationship in the free-weight back squat.

This randomised study compared mid-term effects of supersets (SS) and cluster sets (CL) on neuromuscular performance in amateur male basketball players. Thirty participants were allocated to SS (n = 15) or CL (n = 15) and completed a 6-week full-body resistance training program. Both groups trained squat (SQ) and bench press (BP) with matched volume (18 repetitions per exercise per session) and intensity (75% 1RM). SS alternated SQ and BP with 1-min between exercises and 3-min between supersets; CL inserted 30-s intra-set rests every two reps, used 3-min between sets, and completed all SQ before BP. Pre- and post-tests assessed countermovement jump (CMJ) height, medicine-ball throw (MBT) distance, and load - velocity (L - v) parameters - load-axis intercept (L0), velocity-axis intercept (v0), and area under the L - v relationship line (Aline) - for SQ and BP. Time effects showed significant improvements in CMJ, MBT, L0, and Aline in both groups, whereas v0 did not change (p ≥ 0.627). No time×group interactions were detected (p ≥ 0.085). Between-group differences were trivial, with small non-significant effects favouring SS for SQ v0 (ES = 0.44) and CL for BP Aline (ES = 0.28). Supersets achieved comparable adaptations with substantially shorter rest time (9 vs. 23 min), supporting their use as a time-efficient training strategy.

Tennis-serve landing is a high-intensity single-leg impact requiring coordinated multi-joint control, yet skill-level differences in whole-limb kinetics remain unclear. Fifteen elite and fifteen amateur male players performed Pinpoint serves. 3D kinematics and kinetics were captured. Principal component analysis (PCA) extracted synergy moments (Syn1-Syn2), and vector coding quantified coupling-angle coordination patterns. Two synergy moments explained the dominant variance. In Syn1, elites showed higher contributions from hip/ankle rotation (p = 0.032) and knee abduction-adduction (p < 0.001), whereas amateurs additionally over-weighted ankle plantar-dorsiflexion (p = 0.027). In Syn2, elites emphasised ankle plantar-dorsiflexion and inversion-eversion, hip abduction-adduction, and knee rotation (all p < 0.05 vs. mean); amateurs exceeded the mean only in hip abduction-adduction (p < 0.05) and knee rotation (p = 0.003). Elites showed greater Syn2 prevalence (p < 0.001) and higher proportions of Syn2-dominant anti-phase (p = 0.002) and in-phase patterns (p = 0.013); amateurs showed higher Syn1-dominant anti-phase patterns (p < 0.001). Elites dissipate rotational momentum through functional redundancy across joints, supporting robust stability. Amateurs rely on a stiffer, reactive braking strategy that may increase cumulative tissue loading. Training should develop multi-planar rotational adaptability to optimise landing mechanics and reduce injury risk.

Objective: To compare the between-session reliability of motor units (MUs) behavior derived from high-density surface electromyography (HD-sEMG) during isometric knee extension across three analytical approaches: all identified MUs averaged per participant, tracked MUs averaged per participant, and tracked MUs using individual MUs as the statistical unit. Methods: Seventeen resistance-trained volunteers completed one familiarization and two identical experimental sessions. HD-sEMG signals were assessed in vastus lateralis at 30%, 50%, and 70% of maximum voluntary torque (MVT). Plateau discharge rate, recruitment discharge rate, and recruitment threshold (expressed in %MVT and Nm) were calculated. Reliability was quantified with the Standard error of the measurement (SEM), Coefficient of variation (CV), and Intraclass correlation coefficient (ICC). Results: All identified MUs averaged per participant (CV = 11.7%, ICC = 0.73) yielded comparable reliability than tracked MUs averaged per participant (CV = 13.7%, ICC = 0.68). Using the individual MU as the statistical unit produced the lowest reliability (CV = 16.6%, ICC = 0.58). Conclusions: Averaging all identified MUs per participant achieved reliability comparable to tracking, without the associated sample loss or workload, supporting it as the preferable analytical approach for training interventions.

This study aimed to validate the feasibility of a repetition-based method for adjusting inter-set rest intervals during superset resistance training (RT). Twenty young adults completed three protocols-fixed (3-min rest), self-selected (participant-determined rest), and repetition-based (rest adjusted by prior repetition count)-in randomized order, performing five agonist-antagonist supersets (bench press and bench pull) at 75% 1RM. Results indicated greater repetition volume in later supersets for the self-selected and repetition-based protocols compared to the fixed protocol (F = 2.1, p = 0.037, omega p2 = 0.056). However, blood lactate concentrations were significantly higher in the repetition-based protocol compared to both the self-selected and fixed protocols (F = 7.3, p = 0.002, omega p2 = 0.252). No differences among protocols were found in fastest set velocity or perceived exertion (F = 0.3-2.8, p = 0.077-0.782). Regarding time efficiency, the fixed protocol was most efficient, followed by the repetition-based, with the self-selected protocol being least efficient. These findings indicate that the repetition-based approach offers an effective complementary strategy to traditional fixed and self-selected rest methods, especially in contexts emphasizing mechanical performance and session efficiency.

Abstract:This study examined whether load-velocity relationship variables are sensitive indicators of maximal dynamic strength changes across introductory, overload, and taper microcycles. Twenty resistance-trained men completed a 3-week back squat and bench press program. One-repetition maximum and the two-point load-velocity relationship (20 kg and ~85% one-repetition maximum) were assessed before the introductory microcycle and after each microcycle. The results showed that (i) one-repetition maximum, area under the load-velocity relationship line (A line), and velocity-axis intercept (v 0) derived from peak velocity generally increased after the taper microcycle compared to earlier post-microcycle assessments (p≤0.046, differences=2.3-7.8%); (ii) the overload (coefficient of variation of individual response=5.1%) and taper (3.8%) microcycles exhibited greater variability compared with the introductory microcycle (2.0%). Among the monitored variables, variability was lowest for v 0 (0%), followed by one-repetition maximum and L 0 (4.1%), and highest for A line (5.3%); and (iii) A line derived from mean velocity was the only variable that maintained a significant association with changes in one-repetition maximum across exercises and microcycles (r=0.648-0.765, p≤0.003). These findings indicate that while short mesocycles elicit substantial inter-individual variability in adaptations, A line derived from mean velocity offers a practical, fatigue-free method to monitor meaningful maximal strength changes throughout a training cycle.

Abstract This study aimed to (1) develop an elasticity framework for the sprint force-velocity (F-V) relationship and (2) examine how maximal force ( F 0 ), maximal velocity ( ν 0 ), and sprint distance modulate the four derived elasticity metrics, and (3) explore these elasticity metrics’ interrelation. After modelling the F-V relationship differential equation, four elasticity metrics were defined as force elasticity ( F e ), the elasticity of sprint time to F 0 ; velocity elasticity ( ν e ), the elasticity of sprint time to ν 0 ; the force-velocity elasticity norm capturing the combined sprint time sensitivity to proportional changes in F 0 and ν 0 ; and the force-velocity elasticity ratio, (F −V ER = F e ÷ ν e ), indicating which variable dominates the sprint time response. Model simulations showed that F e decreased with rising F 0 and increased with rising ν 0 , while ν e showed the opposite pattern. With increasing sprint distance, F e decreased and ν e increased. Given its negligible effect on sprint time, ignoring air resistance yields a conservation law (2 F e , + ν e ≡ 1), indicating that a gain in one elasticity metric necessarily diminishes the other in a fixed proportion. This framework also identifies a valley distance ( d valley ) at F − V ER = 2, where F−V EN is minimized and sprint time is least responsive to changes in F-V relationship variables. Empirical data confirmed that the two theoretical laws still hold approximately when air resistance is considered. By linking changes in F 0 and ν 0 to sprint time across different distances, the elasticity framework provides a quantitative basis for estimating the theoretical sprint time response to documented changes in F-V relationship variables.

Objective: To determine the inter-session reliability of MOXY-derived muscle oxygenation (SmO2) in recreationally trained individuals during upper-body strength training. Methods: Eighteen recreationally trained men (mean skinfold thickness at sensor sites = 16.4 +/- 9.4 mm) completed two identical experimental sessions. Participants performed five sets to failure at 70% of one-repetition maximum in bench press and row. SmO2 was recorded from the pectoralis major and latissimus dorsi. Basal SmO2 prior to each set, SmO2 consumption during each set, and SmO2 resaturation during the first 30 s post-set were analyzed. Reliability was assessed using the standard error of measurement (SEM), minimal detectable change (MDC), coefficient of variation (CV), and intraclass correlation coefficient (ICC). Results: Reliability was low for all variables. Basal SmO2 showed SEM = 7.0-17.6%, MDC = 19.5-48.8%, and CV = 10.0-26.5%, with poor ICCs (-0.20 to 0.41). SmO2 consumption and resaturation demonstrated even lower reliability, with SEM = 10.7-21.7%, MDC = 29.6-60.3%, and CV = 25.0-108.2%, with poor to moderate ICCs (-0.34 to 0.74). Conclusions: MOXY-derived SmO2 measurements exhibit limited reliability, particularly during and immediately after training sets. These findings highlight the lack of applicability for using MOXY to monitor SmO2 in recreationally trained individuals during upper-body strength training.

Introduction:Soccer players adopt hamstring-strengthening programs to enhance sprint and change-of-direction (CoD) performance, despite limited information on optimal volume. Therefore, we aimed to compare low, moderate, and high volumes of Nordic curl training on linear sprint and CoD in pubertal soccer players. Methods:Sixty male youth soccer players (13.69 ± 0.31years, 159.43 ± 8.55 cm, 48.51 ± 7.93 kg) were randomly assigned into three groups: low- (n = 20; 4 sets of 3 repetitions), moderate- (n = 20; 4 sets of 6 repetitions), and high-volume Nordic curl training (n = 20; 4 sets of 9 repetitions). The training program lasted 8 weeks in-season. Assessments of sprinting (10 and 20 meters) and CoD performance (15-m-dribbling test with and without a ball) were conducted before and after the intervention. Results:While all three groups improved their performance across all tests, a two-way repeated-measures ANCOVA revealed a significant time × group interaction (p = 0.012) for the 10 m linear sprint, with low- (p = 0.022, d = 0.78) and moderate-volume (p = 0.055, d = 0.71) Nordic curl training yielding better results than high-volume Nordic curl training. Nonsignificant between-group differences were encountered for the 20 m sprints. A significant time × group interaction was observed for the CoD without (p = 0.002) and with the ball (CoDB, p = 0.014), with significantly better results for the low-volume Nordic curl training compared to moderate- (CoD, p = 0.012, d = 0.59; CoDB, p = 0.021, d = 0.60) and high-volume (CoD p = 0.004, d = 0.78; CoDB, p = 0.042, d = 0.56) Nordic curl training. Discussion:Low-volume Nordic curl training is the most effective training dose for improving CoD performance in top-tier youth soccer athletes. For sprint, both low and moderate volumes improve the 10 m sprint more than high volume, and all three volumes improve the 20 m sprint similarly.

This systematic review and meta-analysis sought to quantify the effects of integrated sports vision training (SVT) batteries on time- and accuracy-dependent outcomes assessed during sport-specific tasks and to examine methodological quality and sources of heterogeneity across studies. Following PRISMA 2020 guidelines, PubMed, Embase, Scopus and Web of Science were searched from inception to October 21, 2025. Eligible studies investigated multicomponent visual—cognitive or perceptual—motor training batteries in healthy athletes and reported sport-relevant performance outcomes. Random-effects meta-analyses were conducted separately for time-dependent and accuracy-dependent measures using standardised mean differences (SMDs). Methodological quality was assessed using a modified Downs and Black checklist. Seventeen studies were included in the systematic review, with 14 contributing to the meta-analysis. Integrated SVT batteries produced large and statistically significant improvements in response time (SMD = −2.67, 95

This study examined the reliability and accuracy of various velocity-based methods for predicting the snatch one-repetition maximum (1RM), with the purpose of evaluating the potential of movement velocity as an objective indicator for attempt selection in competitive weightlifting. Fourteen competitive adolescent male weightlifters (age: 15.9 ± 0.9 years; training experience: 5.1 ± 0.9 years) completed two testing sessions, each involving an incremental loading test with attempts at 50%, 70%, 80%, and 90% of their best snatch record from the past 30 days, followed by load increases until reaching their actual 1RM. Peak velocity (PV) was recorded for all lifts with a linear position transducer. The 1RM in the second session was predicted using the load-PV relationship derived from four loads, combined with either the actual or optimal minimal velocity threshold (MVT) obtained in the first session. Additionally, 1RM was estimated from PV recorded at single loads (50%, 70%, 80%, and 90% 1RM), using the individual %1RM-PV relationship established during the first session. Acceptable between-sessions reliability was observed for the actual 1RM, PV tested at single loads (50-90% 1RM), actual MVT, and optimal MVT (intraclass correlation coefficient = 0.76-0.90, coefficient of variation = 1.82-3.31%). The actual MVT, optimal MVT and individual %1RM-PV relationship using 80% and 90% 1RM yielded acceptable and lower absolute errors (2.6-4.1 kg) compared to individual %1RM-PV relationship using 50% and 70% 1RM (6.2-9.9 kg). However, these methods exhibited proportional bias (p = 0.002-0.018). Furthermore, heteroscedasticity was observed for the actual MVT and 90% 1RM methods (p = 0.022-0.026). These results suggest that recording PV during warm-up sets prior to competition may serve as a complementary variable to support and refine opener selection in weightlifting competitions. However, weightlifting coaches should use this approach with caution, as it may not provide accurate snatch performance predictions for all athletes.

We examined whether lifting velocity can serve as an objective indicator for predicting clean and jerk one-repetition maximum (1RM). Fourteen competitive adolescent male weightlifters completed two sessions, each involving an incremental loading test at 50%, 70%, 80%, and 90% of 1RM, followed by load increases until reaching actual 1RM. Peak velocity (PV) was recorded for all lifts using a GymAware device. In second session, 1RM was predicted using the individual load-PV relationship derived from three exercise phases (clean, jerk, and entire movement) combined with either the actual or optimal minimal velocity threshold (MVT) from first session. Absolute errors from the test-retest of the actual 1RM (5.0 kg) were not significantly different to those from all velocity-based methods (range = 6.3-10.2 kg; p=.158-0.730), except for the larger errors obtained for the clean phase combined with the actual MVT (10.1 kg p=.008). Random errors for the actual 1RM (15.7 kg) fell within the range of velocity-based methods (13.2-23.1 kg). These results suggest that, although a direct assessment of the actual 1RM remains the most accurate method, measuring PV during warm-up sets may serve as a supplementary tool for guiding the selection of initial attempts in weightlifting competitions.

Background: Velocity-based training (VBT) is used to estimate maximal strength and prescribe resistance-training loads, but evidence in untrained youth, especially early-adolescent females, is limited. In untrained early-adolescent females performing free-weight back squats, (1) the load–velocity relationship (LVR) is comparable to adult samples, albeit with greater between-subject variability, and (2) one-repetition maximum (1RM) estimates are affected by the minimum velocity threshold (MVT) anchor. Methods: Thirty-four untrained females (10–14 years) completed two progressive loading tests followed by actual 1RM attempts. Mean propulsive velocity (MPV) was recorded to model LVRs. Three MVTs were considered: (a) Actual (from Test 1), (b) General (0.30 m·s−1), and (c) Optimal (individualized to minimize prediction error in Test 1). LVR-based 1RM estimates from Multi-point and Two-point approaches were generated in Test 2 using each MVT and compared with the actual 1RM. Results: MPV decreased near-linearly with load (median R2 ≈ 0.996), from 1.00 ± 0.19 m·s−1 at ~40%1RM to 0.30 ± 0.05 m·s−1 at 100%1RM. Across MVTs, Two- and Multi-point models showed similar 1RM accuracy (≤~0.7% difference; p > 0.35). Actual and General MVTs overestimated 1RM (+5.1 kg; p < 0.001), whereas an individualized Optimal MVT (~0.38 m·s−1) removed bias (+0.6 kg; p = 0.52) and reduced error (p ≈ 0.03). Conclusions: In untrained early-adolescent females, the back-squat LVR is highly linear, and 1RM estimation accuracy hinges on the MVT anchor. A streamlined Two-point LVR paired with an individualized Optimal MVT provides an efficient, accurate workflow for youth strength assessment.

Objective: This article reports the prespecified boxing-specific component of a randomized controlled trial comparing velocity-based resistance training (VBT) with percentage-based training (PBT) in collegiate boxers. Boxing-specific performance was specified as a parallel primary outcome domain in the original ethics-approved protocol, although no single boxing-specific measure was designated as the sole primary endpoint; the five measures are therefore reported as prespecified exploratory outcomes. Methods: The trial was designed before participant recruitment to address two parallel research objectives: changes in general lower-limb performance and changes in boxing-specific performance. Twenty-eight male collegiate boxers were randomly allocated to VBT (n = 14) or PBT (n = 14). Results for lower-limb strength, jumping, and sprinting from the same trial have been reported previously. The present report focuses on lead and rear straight-punch (LSP and RSP) force and continuous-punch (CP) frequency over 10 s, 30 s, and 1 min. Both groups were prescribed the back squat, Bulgarian split-squat, and deadlift twice weekly for eight weeks. PBT participants completed four sets of five repetitions at 70% of one-repetition maximum (1RM), whereas VBT participants were prescribed four sets using the velocity associated with 70% 1RM and ended each set at 10% velocity loss. Results: The between-group differences in mean change, calculated as VBT minus PBT, were 6.97 kg for lead straight-punch force (95% CI: 0.40 to 13.54), 7.21 kg for rear straight-punch force (95% CI: 3.56 to 10.86), 4.47 punches·10 s-1 for 10 s continuous-punch frequency (95% CI: 0.33 to 8.62), 5.05 punches·30 s-1 for 30 s continuous-punch frequency (95% CI: 0.14 to 9.96), and -2.65 punches·min-1 for 1 min continuous-punch frequency (95% CI: -13.97 to 8.67). Conclusions: Greater mean improvements in straight-punch force and short-duration continuous-punch performance were observed in the VBT group, although the precision of several estimates was limited and the findings should be interpreted cautiously because multiple exploratory outcomes were analyzed without formal multiplicity adjustment. For the 1 min test, there was no statistically conclusive evidence of a between-group difference. Registration: The trial was retrospectively registered with the Chinese Clinical Trial Registry (ChiCTR2500111377), and the study materials were subsequently registered on the Open Science Framework (OSF; DOI: 10.17605/OSF.IO/VY6TS).

The menstrual cycle can influence a range of physiological and psychological processes that may affect physical performance. However, existing evidence is inconsistent and often based on isolated testing timepoints rather than typical training conditions. Monitoring kinematic outputs during resistance training allows quantification of day-to-day performance changes. This study evaluated whether kinematic outputs during resistance training vary across menstrual cycle phases over two mesocycles and explored associations with symptoms, and perceived motivation and readiness. This study was conducted at Australian Catholic University (Brisbane, Australia) between February 2023 and June 2025 and was registered with the trial number ACTRN12626000365369. Twenty-eight resistance trained females (mean ± SD; age: 27.1 ± 5.2 years) completed two mesocycles of supervised resistance training. Across the intervention, menstrual cycles were monitored using calendar-based counting, urinary ovulation tests, and retrospective serum 17β-estradiol and progesterone concentrations. Three-repetition maximum (3RM) and load–velocity profiles (LVPs) for the bench press and trap bar deadlift were assessed at baseline, mid training ( 4 weeks), and post training ( 8 weeks). During each training session, kinematic outputs were recorded for all repetitions, with the fastest repetition from each set used to assess training performance across menstrual cycle phases and the observed velocity compared to the expected velocity from the LVP. Symptoms, perceived motivation, and readiness were reported at the start of each resistance training session. Significant differences in observed versus expected average peak mean velocity were found in the bench press during phases 1 and 5, and in the deadlift during phases 1 and 6. For both exercises, observed versus expected average peak mean velocity differed by 0.01–0.02 m·s⁻1 across menstrual cycle phases. After multivariate modeling, motivation to train was a strong predictor of training performance (β = 0.0004, p = 0.021), whereas readiness to perform was not. The symptom domain pain was positively associated with bench press performance (0.00065 m∙s−1 per unit change; p = 0.018), whereas pain was negatively associated with deadlift performance (− 0.001 per unit change; p < 0.001). Additionally, no significant main effect was found for the symptom domain control, but a between-exercise difference was found (p < 0.03). No other symptom domains showed significant relationships with training performance. Menstrual cycle phase appears to have minimal effect on resistance training performance, with kinematic outputs demonstrating modest differences compared to what would be expected. Consequently, these findings support consistent resistance training across the menstrual cycle, without the need for phase-based adjustments to maintain performance. However, motivation and symptom profiles may influence resistance training across the menstrual cycle.