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The Influence of the Menstrual Cycle on Muscle Strength and Power Performance

effects of different phases of the menstrual cycle on muscle strength and power performance as assessed using barbell velocity measures across low, moderate, and high loading zones. Therefore, the aim of this study was to investigate muscle performance variations across three phases of the menstrual cycle (ELP, LFP, and MLP) by measuring velocity, power and force output in the Smith machine half-squat exercise with loads equivalent to 20, 40, 60 and 80% of 1RM. Methods Participants Thirteen female triathletes volunteered to participate in this study (age = 31

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Power Performance of the Combined Monopile Wind Turbine and Floating Buoy with Heave-type Wave Energy Converter

., Extreme responses of a combined spar-type floating wind turbine and floating wave energy converter (STC) system with survival modes. Ocean Engineering, 2013. 65 : pp. 71-82. 9. Muliawan, M.J., M. Karimirad, and T. Moan, Dynamic response and power performance of a combined spar-type floating wind turbine and coaxial floating wave energy converter. Renewable Energy, 2013. 50 : pp. 47-57. 10. Muliawan, M.J., et al. STC (Spar-Torus Combination): a combined spar-type floating wind turbine and large point absorber floating wave energy converter—promising and

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Impact of Official Matches on Soccer Referees’ Power Performance

regarded as an appropriate test for evaluating power performance of the lower limbs, and has the benefit of being directly related to refereeing ( Tessitore et al., 2007 ). Although some researchers have observed a significant decrease in soccer players’ lower limb power as measured by the vertical jump test after a soccer match ( Nedelec et al., 2014 ), other researchers have found that athletes show higher lower limb power after fatiguing tasks ( Boullosa and Tuimil, 2009 ; Boullosa et al., 2011 ). A study of match officials concluded that soccer referees’ jumping

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The Effect of Active Recovery on Power Performance During the Bench Press Exercise

Abstract

The objective of this study was to verify the effect of active and passive recovery on blood lactate concentration and power performance. Twelve male subjects were submitted to a maximal strength test in the the bench press, a maximal aerobic test in the bench step, and to four sets of bench press exercise performed as fast and as long as possible, using 80% of maximal strength when active or passive recovery was performed. The maximum number of repetitions, mean and peak power in eccentric and concentric phases were computed and blood lactate concentration was measured. Comparisons for the variables were made using a two-way variance analysis (recovery type and set numer) with repeated measures in the second factor. When significant differences were detected (p < 0.05), a Tukey post-hoc test was used. There was a main effect of set number on maximum number of repetitions (p < 0.05) (1 > 2, 3, and 4; 2 > 3 and 4; 3 > 4). Mean and peak power in both eccentric and concentric phases also differed across sets (1 > 2, 3, and 4; 2 > 4). There was also a main effect for the recovery type, with lower values (p < 0.05) observed for the active recovery compared to the passive one. It can be concluded that active recovery resulted in lower lactate concentration, but did not improve power performance in the bench press exercise.

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Some Practical Design Aspects of Appendages for Passenger Vessels

Abstract

The hydrodynamic effect of appendages for high-speed passenger vessels, such as Ro-Pax, Ro-Ro and cruiser vessels, is very severe and, therefore, it is essential to carry out the design of appendages for high-speed passenger vessels from the preliminary design stage to the final detail design stage through a full survey of the reference vessels together with sufficient technical investigation. Otherwise, many problems would be caused by mismatches between the appendages and the hull form. This paper investigates the design characteristics of some appendages, such as the side thruster, the shaft-strut, and the stern wedge, based on the design experience accumulated at Samsung, on CFD, and on model test results for high-speed passenger vessels. Further to this investigation, some practical and valuable design guidelines for such appendages are suggested.

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A RANS modelling approach for predicting powering performance of ships in waves

(Schiffstechnik), 57(2), pp.128-139. Windén, B., 2012. Powering performance of ships in waves. M.Phil/Ph.D Transfer thesis. University of Southampton. Windén, B., Turnock, S. and Hudson, D., 2012. Validating force calculations using OpenFOAM© on a Fixed Wigley hull in waves. In Proceedings of the 15th Numerical Towing Tank Symposium, Cortona, Italy, 7-9 October 2012, pp.170-175. Windén, B., Turnock, S. and Hudson, D., 2013. Predicting powering performance changes for ships in offshore conditions from small design modifications. In

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Effect of 8 weeks of free-weight and machine-based strength training on strength and power performance

Abstract

The aim of this study was to evaluate the effectiveness of free-weight and machine-based exercises to increase different strength and speed-strength variables. One hundred twenty male participants (age: 23.8 ± 2.5 years; body height: 181.0 ± 6.8 cm; body mass: 80.2 ± 8.9 kg) joined the study. The 2 experimental groups completed an 8 week periodized strength training program that included 2 training sessions per week. The exercises that were used in the strength training programs were the parallel barbell squat and the leg press. Before and after the training period, the 1-repetition-maximum in the barbell squat and the leg press, the squat jump, the countermovement jump and unilateral isometric force (maximal isometric force and the rate of force development) were evaluated. To compare each group pre vs. post-intervention, analysis of variance with repeated measures and Scheffé post-hoc tests were used. The leg press group increased their 1-repetition-maximum significantly (p < 0.001), while in the squat group such variables as 1-repetition-maximum, the squat jump and the countermovement jump increased significantly (p < 0.001). The maximal isometric force showed no statistically significant result for the repeated measures factor, while the rate of force development of the squat group even showed a statistically significant decrease. Differences between the 2 experimental groups were detected for the squat jump and the countermovement jump. In comparison with the leg press, the squat might be a better strength training exercise for the development of jump performance.

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Performance Changes of Elite Paralympic Judo Athletes During a Paralympic Games Cycle: A Case Study with the Brazilian National Team

been reported as a discriminant factor in Olympic judo ( Franchini et al., 2011 ; Zaggelidis and Lazaridis, 2012 ). Nevertheless, no study was found analyzing the development of muscle power across a competitive season in Paralympic judokas. Thus, the main objective of this study was to describe the variations in power performance of elite Paralympic judokas throughout a competitive training season including such important events as the ParaPan American Games, the World Championship and the Paralympic Games. Methods Participants Eleven Paralympic judo

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Transference of Traditional Versus Complex Strength and Power Training to Sprint Performance

heavy-resistance and plyometric training. J Sei Med Sport, 2013; 16(2): 146-150 Sanchez-Medina L, Perez CE, Gonzalez-Badillo JJ. Importance of the propulsive phase in strength assessment. Int J Sports Med, 2010; 31(2): 123-129 Weiss LW, Fry AC, Wood LE, Relyea GE, Melton C. Comparative Effects of Deep Versus Shallow Squat and Leg-Press Training on Vertical Jumping Ability and Related Factors. J Strength Cond Res, 2000; 14(3): 241-247 Young WB, Jenner A, Griffiths K. Acute Enhancement of Power Performance From Heavy Load Squats. J Strength Cond Res, 1998

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Effect of Additional Load on Power Output during Drop Jump Training

:133-139. Gehri DJ, Ricard MD, Kleiner DM, Kirkendall DT. A comparison of plyometric training techniques for improving vertical jump ability and energy production. J Strength Cond Res. 1998; 12:85-89. Gollhofer A, Kyrolainen H. Neuromuscular control of the human leg extensor muscles in jump exercises under various stretch-load conditions. Int J Sports Med. 1991; 12:34-40. Hoffman JR, Ratamess NA, Cooper JJ, Kang J, Chilakos A, Faigenbaum AD. Comparison of loaded and unloaded jump squat training on strength/power performance in

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