1. Trunk muscle loading and hip angle adjustments during simulated hiking in International Laser Class Association sailors : implications for athletic conditioningLin Pletikos, Žiga Kozinc, Oskar Cvjetičanin, Andrej Kocjan, 2026, izvirni znanstveni članek Opis: Background and purpose The hiking position is a fundamental technique in International Laser Class Association dinghy sailing that requires prolonged trunk muscle activation to counteract external heeling forces. However, the influence of hip angle on trunk muscle activation during hiking has not been sufficiently investigated. From an applied perspective, clarifying this relationship could help coaches and strength and conditioning specialists use hip-angle adjustments to target different trunk-loading demands during simulator-based training. Therefore, the purpose of this pilot study was to determine how different hip angles in the hiking position on a sailing simulator affect trunk muscle activation in Slovenian sailors competing in International Laser Class Association classes. Material and methods Ten competitive International Laser Class Association sailors participated in the study. Maximal voluntary contractions of selected trunk muscles were recorded before testing. Participants then performed two trials on a sailing simulator at three hip angles (extended, semi-flexed, and flexed). Surface electromyography was used to assess rectus abdominis, external oblique, internal oblique, and erector spinae activation, with values normalized to each participant’s maximal voluntary contraction. Results Hip angle had a significant effect on rectus abdominis activation (59.3 ± 18.5%, 30.8 ± 14.2%, and 14.9 ± 10.7% of maximal voluntary contraction for the extended, semi-flexed, and flexed positions, respectively; p < 0.001), external oblique activation (46.2 ± 17.2%, 31.9 ± 8.9%, and 21.7 ± 8.5% of maximal voluntary contraction; p = 0.002), and internal oblique activation (24.9 ± 7.6%, 15.5 ± 6.7%, and 13.8 ± 8.4% of maximal voluntary contraction; p = 0.002). Erector spinae activation remained low across all conditions (5.4 ± 4.2%, 3.6 ± 2.0%, and 3.2 ± 2.0% of maximal voluntary contraction) and did not differ significantly between hip angles (p = 0.082). Conclusions Greater hip extension during a simulated hiking position was associated with increased activation of the rectus abdominis, external oblique, and internal oblique muscles, whereas erector spinae activation remained low. These acute responses indicate that hip angle can be used as a practical loading variable when planning hiking-simulator technique and conditioning sessions
Ključne besede: sailing, muscles, exercise
Objavljeno v RUP: 14.09.2026; Ogledov: 304; Prenosov: 7
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2. Acute effects of Nordic hamstring exercise and Romanian deadlift on hamstring shear modulus and flexibilityKlemen Kalc, Amadej Jelen, Masatoshi Nakamura, Konstantin Warneke, Živa Jovanović, Leja Budja, Žiga Kozinc, 2026, izvirni znanstveni članek Opis: The aim of this study was to investigate the acute effects of Romanian deadlift (RDL) and Nordic hamstring exercise (NHE) on the stiffness and flexibility of hamstring muscles. We hypothesized that a) the RDL would have a greater acute effect on increasing the flexibility, b) the NHE would have a greater acute effect on the increase in stiffness of the biceps femoris (BF) and semitendinosus (ST) in comparison to the semimembranosus (SM), and c) RDL would have a greater acute effect on the increase in stiffness of the SM in comparison to the ST. Twelve young, healthy participants (6 females; 22.8±3.0 years) performed RDL, and 12 participants (8 females; 22.8±3.1 years) performed NHE, with both interventions comprising 5 sets of 10 repetitions. Baseline and post-intervention stiffness was measured using shear– wave elastography, and flexibility using the passive straight leg raise test. There were no significant main effects of time (p=0.744), group (p=0.202), nor the interaction between time and group (p=0.131) for shear modulus. Similarly, no significant main effects of time (p=0.717) and group (p=0.856), nor an interaction between time and group (p=0.444), were observed for flexibility. These findings suggest that neither RDL nor NHE induce immediate measurable changes in hamstring muscle stiffness or flexibility. However, given the small group-specific sample size, the absence of significant effects should be interpreted cautiously and cannot be generalized beyond young, healthy recreationally active individuals.
Ključne besede: hamstring muscles, stiffness, ultrasound
Objavljeno v RUP: 01.06.2026; Ogledov: 645; Prenosov: 17
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3. Single muscle fibre contractile properties differ between body-builders, power athletes and control subjectsJ. P. Meijer, R. T. Jaspers, Joern Rittweger, Olivier Seynnes, S. Kamandulis, M. Brazaitis, A. Skurvydas, Rado Pišot, Boštjan Šimunič, Marco Vincenzo Narici, Hans Degens, 2015, izvirni znanstveni članek Ključne besede: skeletal muscles, muscle fibers, contractile properties, body-builders, power athletes
Objavljeno v RUP: 08.08.2016; Ogledov: 7594; Prenosov: 212
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4. Effects of whole-body cryotherapy on recovery after hamstring damaging exerciseBorut Fonda, Nejc Šarabon, 2013, izvirni znanstveni članek Opis: The purpose of this study was to examine the effects of whole-body cryotherapy (WBC) on biochemical, pain, and performance parameters during the 5-day recovery period after damaging exercise for hamstrings. Participants completed a bout of damaging exercise for the hamstring muscles on two separate occasions (control and experimental condition) separated by 10 weeks. During the control condition, subjects received no treatment after the damaging exercise. The experimental condition consisted of WBC everyday during the recovery period. WBC included single 3-min daily exposures to low temperatures (-140 to -195 °C) in the cryo-cabin. During the recovery period, subjects were tested for biochemical markers, perceived pain sensation, and physical performance (squat jump, counter movement jump, maximal isometric torque production, and maximally explosive isometric torque production). Majority of the observed variables showed statistically significant time effects (P < 0.05) in control group, which indicates the presence of muscle damage. Significant interaction between the control and WBC condition was evident for the rate of torque development (P < 0.05). Pain measures substantially differed between the WBC and the control condition after the exercise. Results of this study are not completely supportive of the use of WBC for recovery enhancement after strenuous training
Ključne besede: whole-body cryotherapy, damaging exercise, hamstring muscles, recovery
Objavljeno v RUP: 15.10.2013; Ogledov: 7876; Prenosov: 106
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