1. Rate of torque development scaling factor decreased following a 6-week unilateral isometric training using electrostimulation or voluntary contractionsOlivera Knežević Milović, Nejc Šarabon, Amador García Ramos, Nikola Majstorović, Sladjan D. Milanović, Saša R. Filipović, Dragan Mirkov, 2024, izvirni znanstveni članek Opis: This study explored the changes in the rate of torque development scaling factor (RTD-SF) and maximum voluntary isometric contraction (MVC) variables following six weeks of unilateral isometric electromyostimulation (EMS) and voluntary (VOL) exercises. Twenty-six physically active participants were randomly assigned to EMS (n = 13) or a VOL group. MVC and RTD-SF of the quadriceps femoris of both legs were assessed before and after training. EMS and VOL exercises had identical frequency (three sessions/week), intensity (60% MVC), volume (40 contractions), and work-to-rest ratio (18 min: 6.25 s of work/20 s of rest). There were no between-group differences for the trained leg with overall increases in maximal torque (Tmax) of ~29% (d = 2.11–2.12), ~13% for RTDmax (d = 0.92–1.10); ~23% for Intercept (d = 0.72–0.78), and reduction in RTD-SF by ~15% (d = 1.01–1.10). In the non-trained leg, significant moderate change was only observed after EMS for RTD-SF which decreased by 12.5% (d = 0.76)
Ključne besede: quadriceps, strength, RTD-SF, RFD-SF, EMS
Objavljeno v RUP: 14.01.2026; Ogledov: 136; Prenosov: 0
 Celotno besedilo (1,42 MB)
Gradivo ima več datotek! Več... |
2. Effects of different lifting strategies during resistance training on lower body function in untrained adult women : a comparison between 6-weeks of 10% velocity loss and standard resistance trainingMatic Sašek, Hana Golob, Nejc Šarabon, 2026, izvirni znanstveni članek Opis: Introduction: This study investigated whether velocity-based resistance training provides additional benefits to lower limb performance compared to standard exercise execution. Methods: Twenty untrained adult women (37–55 years) were randomly assigned to two resistance training groups to perform resistance training with three sets of four lower body exercises per week for 6 weeks. The number of repetitions and lifting velocity differed between the groups. One group performed lower body exercises with maximal intent and a 10% velocity loss threshold termination (VB10%; n = 10), while the other group performed 10 repetitions at a standard 1:2 s concentric:eccentric tempo (STD; n = 10). The number of repetitions was recorded during the sessions. Before and after the intervention, power, muscular endurance and dynamic stability of the lower limbs were assessed using the mean propulsive velocity (MPV) and power (MPP) at 70% one-repetition maximum in the squat and deadlift, the Y-balance test (YBT) and the 30-second sit-to-stand test (STS), respectively. A two-way analysis of variance was used to assess the effects of time, group, and their interaction. Results: The difference between 10 repetitions in the STD and repetitions in the VB10% was assessed using a one-sample t-test. Both groups significantly improved MPP, MPV, YBT and STS [mean difference (MD) ≥5.4%; effect size (ES) ≥0.6]. Although 2.5–2.7 less repetitions were performed in VB10%, the improvements in MPP and MPV were slightly greater (ES ≥ 1.2 vs. ≥ 0.8). Conversely, STS and YBT improved more in STD (ES ≥ 0.4 vs. ≥ 1.0). Discussion: Regardless of the lifting method used, the training intervention improved lower limb power, muscular endurance and dynamic stability, indicating that resistance training is an effective strategy for enhancing these capacities in untrained adult women. Using 10% threshold may be a more time-efficient strategy for improving lower-limb power in this population and could represent a promising approach for mitigating early declines in power over time.
Ključne besede: adult women, dynapenia, muscle performance, power, powerpenia, resistance training, strength, velocity loss
Objavljeno v RUP: 14.01.2026; Ogledov: 175; Prenosov: 2
Celotno besedilo (781,98 KB)
Gradivo ima več datotek! Več... |
3. Enhanced paper grip test for foot strength assessment in healthy young adults : test–retest reliability and comparison with handgripNenad Nedović, Stevan Jovanović, Danilo Vujičić, Vladimir Gapić, Žiga Kozinc, 2026, izvirni znanstveni članek Ključne besede: strength, power, thumb, measurements
Objavljeno v RUP: 11.01.2026; Ogledov: 157; Prenosov: 0
Celotno besedilo (763,82 KB)
Gradivo ima več datotek! Več... |
4. Dynamic strength index in athletic performance : a comprehensive analysis of theory, measurement and practical applicationMarko Joksimović, Ratko Pavlović, Vladimir Koprivica, Matej Plevnik, 2025, izvirni znanstveni članek Opis: Background and purposeThe development of athletic performance requires a detailed assessment of the relationship between maximal strength and the ability to express it explosively. Traditional tests one-repetition maximum do not differentiate the rate of force development, which led to the introduction of the Dynamic Strength Index, defined as the ratio between force in the countermovement jump and the isometric mid-thigh pull . The aim of this paper was to present the theoretical background, methodological approaches, and practical applications of Dynamic Strength Index in order to optimize training and prevent injuries.Materials and methodsDynamic Strength Index is calculated by measuring peak force in countermovement jump and isometric mid-thigh pull tests using a force plate. Standardization of protocols (body position, contraction duration, software processing) is essential for validity. Test–retest reliability is high (Intraclass Correlation Coefficient >0.90). Normative values vary by sport and playing position: for example, sprinters and jumpers often record Dynamic Strength Index values >0.80, while weightlifters usually show lower values (<0.60).ResultsFindings indicate that DSI is an effective tool for training individualization. Values below 0.60 suggest the need for plyometric and ballistic training, while values above 0.80 point to a focus on maximal strength development. The optimal range (0.60–0.80) reflects a balanced profile. DSI is also useful for longitudinal monitoring of adaptations, adjusting training loads, and identifying injury risks. However, variability in testing protocols, anthropometric differences, and software processing may limit its applicability and comparability across studies.ConclusionDynamic Strength Index is a valuable biomechanical indicator linking maximal and explosive strength, allowing precise programming of training and performance monitoring. Its use has already been established in elite sports, but full validation requires measurement standardization and the development of sport-specific normative databases. Future directions include phase-specific force analysis within contraction cycles, expanding testing protocols, and integrating digital platforms for automated analysis.
Ključne besede: strength, index, performance
Objavljeno v RUP: 28.12.2025; Ogledov: 206; Prenosov: 3
Celotno besedilo (822,95 KB)
Gradivo ima več datotek! Več... |
5. Experimental and analytical evaluation of shear capacity of reclaimed timber connections with thermo-mechanically densified wooden dowelsMohammad Derikvand, Donya Bazyar Khoshroodi, 2025, izvirni znanstveni članek Opis: The reuse of reclaimed timber in structural applications is increasingly recognized as a strategy to extend ma- terial life cycles and reduce waste. Particular attention has recently turned to reusing reclaimed timber in adhesive-free laminated products with wooden dowels, where connection performance is critical. The aim of this study was to investigate the mechanical performance of double-shear connections assembled from reclaimed spruce timber using thermo-mechanically densified wooden dowels. The dowels were first evaluated in bending and embedment tests on lamellae made from both reclaimed and virgin spruce timber. The shear capacity of the connections was then evaluated in three layups: two homogeneous (all-reclaimed lamellae and all-virgin spruce lamellae) and one hybrid (reclaimed side lamellae with a central virgin spruce lamella). Analytical predictions were performed based on the draft of the new Eurocode 5, however, with two alternative definitions of dowel bending resistance (ultimate moment Mu and yield moment My), and three alternative definitions of embedment strength (f 0.05d h calculated using the 0.05 d offset method, f Fmax h calculated from Fmax, and f 0.8Fmax h calculated from 0.8 Fmax). The three lamellae layups exhibited relatively similar mean capacities (7.3–8.3 kN). The all-reclaimed connections were on average 13 % stronger than the other assemblies, but this was not statistically significant. Among the model input variants, Mu with f 0.05d h showed the closest agreement with the experimental mean values, while My with f 0.05d h led to more conservative predictions preferable for design. In both cases, excluding outliers from the embedment test results reduced overestimation in the predictions. All other input variants overestimated the shear capacity. Overall, both homogeneous and hybrid connections with reclaimed timber lamellae performed comparably to virgin timber connections and exhibited predictable mechanical behavior.
Ključne besede: reclaimed timber, wood densification, structural reuse, embedment strength, dowel connections, European yield model, Eurocode 5
Objavljeno v RUP: 17.12.2025; Ogledov: 182; Prenosov: 3
Celotno besedilo (23,08 MB)
Gradivo ima več datotek! Več... |
6. Relationship between curvilinear sprint performance, hip strength, jump performance and reactive strength in elite youth soccer playersAžbe Ribič, Matic Sešek, 2025, izvirni znanstveni članek Opis: The aim of this study was to investigate the relationships between hip strength, vertical jump performance, reactive strength index, and curvilinear sprint (CS) performance and to compare these variables between different playing positions in youth soccer players. Thirty-four players completed two test sessions. Hip adduction and abduction strength was measured using a hand-held dynamometer. A force plate was used to measure the height of the countermovement jump and the drop jump as well as the contact time, from which the modified reactive strength index and the reactive strength index (RSI) were calculated. The CS was tested on the penalty arch of a soccer pitch. One way ANOVA was used to test the effects of playing position whereas the Pearson's r was used to test the relationship between variables. There were no significant differences in the measured variables between defenders, midfielders and attackers (p≥ .140). Along with RSI, which showed significant moderate to large correlations (r = -0.39 to -0.59), hip abduction strength was also significantly associated with CS split times (r = -0.36 to -0.38). Results emphasize the relevance of ankle reactive strength and hip strength for CS performance and supports the inclusion of ankle and hip-specific strength exercises in the training of youth soccer players.
Ključne besede: curvilinear sprint, hip strength, reactive strength, vertical jump, soccer
Objavljeno v RUP: 12.12.2025; Ogledov: 266; Prenosov: 4
 Povezava na datoteko
Gradivo ima več datotek! Več... |
7. Joint torque and electromyographic activity during eccentric exercise for hip adductors at different hip flexion anglesJan Marušič, Oskar Cvjetičanin, Nejc Šarabon, 2025, izvirni znanstveni članek Opis: Our objective was to investigate the effects of three hip flexion angles (0°, 45°, and 90°) and leg dominance on peak joint torque, angle at peak torque, and peak electromyographic activity (EMGA) of the adductor longus during bilateral eccentric hip adduction. Sixteen recreationally active participants completed bilateral eccentric contractions at each hip flexion angle using a custom-built dynamometer. The primary outcome measures were peak adduction torque, angle at peak torque, and EMGA of the adductor longus. A 3×2 repeated measures ANOVA was used to assess the effects of hip angle and leg dominance. Hip flexion angle had a significant main effect on peak torque (F(2, 30) = 15.75, p<0.01), with peak torque significantly lower at 90° compared to 0° and 45°. No significant effects were observed for leg dominance or interaction. No significant main effects of hip flexion angle, leg dominance, or their interaction were observed on peak EMGA or peak torque angle. Eccentric hip adduction strength is reduced at 90° of flexion, likely due to mechanical disadvantage, while neural activation remains unchanged. These findings support the use of less flexed positions in eccentric training protocols for adductor strength development or injury prevention.
Ključne besede: adductor longus, eccentric training, injury prevention, strength
Objavljeno v RUP: 19.11.2025; Ogledov: 364; Prenosov: 9
Celotno besedilo (554,32 KB)
Gradivo ima več datotek! Več... |
8. Size effect on bending strength and failure modes of finger-jointed timberMohammad Derikvand, Michael David Burnard, Donya Bazyar Khoshroodi, Rok Barbič, Marko Vouk, Andreja Kutnar, 2025, izvirni znanstveni članek Opis: Finger-jointed timber boards for cross-laminated timber production are typically assigned the same characteristic bending strength (fm,j,k) if produced from the same strength class, regardless of differences in their cross-sectional dimensions. To validate the relevance of this approach, this study investigated the effects of cross-sectional dimensions on the bending performance of finger-jointed timber produced from spruce (strength class: C24). A large industrial dataset of 1100 specimens, with seven thicknesses (ranging 20 to 40 mm) and variable widths, were statistically analyzed. The bending tests were performed with a constant span-to-depth ratio (l/h = 18), meaning thinner specimens had a shorter test span. Bending strength was modeled with Bayesian multilevel linear model, and the proportions of three quality-control failure modes (joint interface failure, joint base failure, and outside-joint failure) were analyzed with a zero-one-inflated Dirichlet regression. Based on the results, all groups with n ≥ 100 exceeded the declared fm,j,k of 27.6 MPa, with characteristic strengths of 43.7 MPa (+58.3 %), 40.0 MPa (+45.0 %), and 38.3 MPa (+38.8 %) for the 20-, 30-, and 40-mm thickness groups, respectively. Thinner specimens demonstrated higher bending strength with convincing evidence (pairwise contrasts PD = 100 % with 95 % HDPIs entirely below zero), while width had no credible effect (PD < 95 %). Dirichlet regression revealed shifts in failure mode proportions with varying strength. Higher bending strengths were associated with a higher proportion of joint interface failure. Outside‑joint failure was observed with a higher proportion in lower-strength and thicker specimens. Overall, assigning uniform fm,j,k to various cross-sectional dimensions proved to give adequate safety margins. Beyond the uniform fm,j,k, however, statistical evidence of a size effect on both bending strength and failure modes was observed. The magnitude of the observed size effect reflects the combined influence of increasing thickness and test span under the current quality control bending test regime, which means a coupled change in stressed volume and geometry rather than a pure cross-section scaling effect. These findings are relevant to flatwise four-point bending tests on finger-jointed boards from industrial production made with visually graded C24 spruce with thickness ranging 20 to 40 mm.
Ključne besede: wood, finger joint, strength
Objavljeno v RUP: 18.11.2025; Ogledov: 320; Prenosov: 5
Celotno besedilo (4,20 MB)
Gradivo ima več datotek! Več... |
9. |
10. |
