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Strength Performance Assessment in a Simulated Men's Gymnastics Still Rings CrossDunlavy, Jennifer K., Sands, William A., McNeal, Jeni R., Stone, Michael H., Smith, Sarah L., Jemni, Monem, Haff, G. Gregory 01 March 2007 (has links)
Athletes in sports such as the gymnastics who perform the still rings cross position are disadvantaged due to a lack of objective and convenient measurement methods. The gymnastics "cross" is a held isometric strength position considered fundamental to all still rings athletes. The purpose of this investigation was to determine if two small force platforms (FPs) placed on supports to simulate a cross position could demonstrate the fidelity necessary to differentiate between athletes who could perform a cross from those who could not. Ten gymnasts (5 USA Gymnastics, Senior National Team, and 5 Age Group Level Gymnasts) agreed to participate. The five Senior National Team athletes were grouped as cross Performers; the Age Group Gymnasts could not successfully perform the cross position and were grouped as cross Non-Performers. The two small FPs were first tested for reliability and validity and were then used to obtain a force-time record of a simulated cross position. The simulated cross test consisted of standing between two small force platforms placed on top of large solid gymnastics spotting blocks. The gymnasts attempted to perform a cross position by placing their hands at the center of the FPs and pressing downward with sufficient force that they could remove the support of their feet from the floor. Force-time curves (100 Hz) were obtained and analyzed for the sum of peak and mean arm ground reaction forces. The summed arm forces, mean and peak, were compared to body weight to determine how close the gymnasts came to achieving forces equal to body weight and thus the ability to perform the cross. The mean and peak summed arm forces were able to statistically differentiate between athletes who could perform the cross from those who could not (p < 0.05). The force-time curves and small FPs showed sufficient fidelity to differentiate between Performer and Non-Performer groups. This experiment showed that small and inexpensive force platforms may serve as useful adjuncts to athlete performance measurement such as the gymnastics still rings cross.
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Is Testosterone Influencing Explosive Performance?Cardinale, Marco, Stone, Michael H. 01 February 2006 (has links)
The primary objective of this study was to analyze the relationship between testosterone levels and vertical jumping performance in elite men and women athletes. The secondary objective was to verify whether testosterone levels and vertical jumping performance were different in men and women athletes and if those measurements were different between different athletic groups. Seventy (22 women and 48 men) elite athletes in track and field (sprinters), handball, volleyball, and soccer competing at national and international levels participated in the study. After 10 hours of fasting and 1 day of rest, blood samples were drawn from the antecubital vein for determining testosterone levels. Vertical jumping tests consisted of countermovement jumps conducted on a resistive platform connected to a digital timer. Resting testosterone levels in women were 9.5% of those of the men (respectively 0.62 ± 0.06 ng·ml-1 and 6.49 ± 0.37 ng·ml-1; p < 0.001). Countermovement jump performance was significantly different between women and men athletes, with women's jumping ability 86.3% of that of men (p < 0.001). A significant positive relationship was identified between testosterone levels and vertical jump performance when all data where considered (r = 0.61, p < 0.001, n = 70).
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Weightlifting: A Brief OverviewStone, Michael, Pierce, Kyle C., Sands, William A., Stone, Meg E. 01 February 2006 (has links)
This is the first part of a 2-part discussion on weightlifting and will describe the historical and scientific background of the sport.
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Stretching: Acute and Chronic? the Potential ConsequencesStone, Mike, Ramsey, Michael W., Kinser, Ann M., O'Bryant, Harold S., Ayers, Chris, Sands, William A. 01 January 2006 (has links)
Stretching is commonly used by many athletes in different sports. Although acute stretching, as part of a warm-up, can enhance range of motion, it may also reduce performance. Acute stretching can reduce peak force, rate of force production, and power output. Chronic stretching may enhance performance, although the mechanism is unclear. Acute stretching has little effect on injury. However, chronic stretching (not part of warm-up) may have some injury reduction potential.
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Weightlifting: Program DesignStone, Michael, Pierce, Kyle C., Sands, William A., Stone, Meg E. 01 January 2006 (has links)
This is the second part of a 2-part discussion (the first, "Weightlifting: A Brief Overview," appeared 28(1):50-66, 2006) on weightlifting and will describe the best methods of designing a weightlifting program.
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Periodization and Block Periodization in Sports: Emphasis on Strength-Power Training-A Provocative and Challenging NarrativeStone, Michael H., Hornsby, William G., Haff, G. G., Fry, Andrew C., Suarez, Dylan G., Liu, Junshi, Gonzalez-Rave, Jose M., Pierce, Kyle C. 01 August 2021 (has links)
ABSTRACT: Stone, MH, Hornsby, WG, Haff, GG, Fry, AC, Suarez, DG, Liu, J, Gonzalez-Rave, JM, and Pierce, KC. Periodization and block periodization in sports: emphasis on strength-power training-a provocative and challenging narrative. J Strength Cond Res 35(8): 2351-2371, 2021-Periodization can be defined as a logical sequential, phasic method of manipulating fitness and recovery phases to increase the potential for achieving specific performance goals while minimizing the potential for nonfunctional over-reaching, overtraining, and injury. Periodization deals with the micromanagement of timelines and fitness phases and is cyclic in nature. On the other hand, programming deals with the micromanagement of the training process and deals with exercise selection, volume, intensity, etc. Evidence indicates that a periodized training process coupled with appropriate programming can produce superior athletic enhancement compared with nonperiodized process. There are 2 models of periodization, traditional and block. Traditional can take different forms (i.e., reverse). Block periodization has 2 subtypes, single goal or factor (individual sports) and multiple goals or factors (team sports). Both models have strengths and weaknesses but can be "tailored" through creative programming to produce excellent results for specific sports.
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Training for Muscular Strength: Methods for Monitoring and Adjusting Training IntensitySuchomel, Timothy J., Nimphius, Sophia, Bellon, Christopher R., Hornsby, W. G., Stone, Michael H. 01 October 2021 (has links)
Linear loading, the two-for-two rule, percent of one repetition maximum (1RM), RM zones, rate of perceived exertion (RPE), repetitions in reserve, set-repetition best, autoregulatory progressive resistance exercise (APRE), and velocity-based training (VBT) are all methods of adjusting resistance training intensity. Each method has advantages and disadvantages that strength and conditioning practitioners should be aware of when measuring and monitoring strength characteristics. The linear loading and 2-for-2 methods may be beneficial for novice athletes; however, they may be limited in their capacity to provide athletes with variation and detrimental if used exclusively for long periods of time. The percent of 1RM and RM zone methods may provide athletes with more variation and greater potential for strength–power adaptations; however, they fail to account for daily changes in athlete’s performance capabilities. An athlete’s daily readiness can be addressed to various extents by both subjective (e.g., RPE, repetitions in reserve, set-repetition best, and APRE) and objective (e.g., VBT) load adjustment methods. Future resistance training monitoring may aim to include a combination of measures that quantify outcome (e.g., velocity, load, time, etc.) with process (e.g., variability, coordination, efficiency, etc.) relevant to the stage of learning or the task being performed. Load adjustment and monitoring methods should be used to supplement and guide the practitioner, quantify what the practitioner ‘sees’, and provide longitudinal data to assist in reviewing athlete development and providing baselines for the rate of expected development in resistance training when an athlete returns to sport from injury or large training load reductions.
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Body Mass and Femur Length Are Inversely Related to Repetitions Performed in the Back Squat in Well-Trained LiftersCooke, Daniel M., Haischer, Michael H., Carzoli, Joseph P., Bazyler, Caleb D., Johnson, Trevor K., Varieur, Robert, Zoeller, Robert F., Whitehurst, Michael, Zourdos, Michael C. 01 January 2019 (has links)
The purpose of this research note was to examine whether relationships existed between anthropometrics (body mass, body fat percentage [BF%], and femur length) and descriptive characteristics (age and sex) with repetitions performed to failure at 70% of 1 repetition maximum (1RM) in the back squat. Fifty-eight subjects (males = 43, females = 15; age: 23 ± 3 years, training age: 5.5 ± 2.5 years, body mass: 80.65 ± 16.34 kg, BF%: 10.98 ± 3.53%, and femur length: 47.1 ± 2.6 cm) completed a 1RM squat followed by one set to failure at 70% of 1RM. Total repetitions performed at 70% of 1RM were 14 ± 4 (range: 6–26). Bivariate correlations showed significant inverse relationships between body mass (r = -0.352, p = 0.003), BF% (r = -0.278, p = 0.014), and femur length (r = -0.265, p = 0.019), with repetitions performed. No significant relationships existed between age and sex (p > 0.05), with repetitions performed. All these variables entered into a standard multivariate regression. The model R2 was 0.200, and body mass had the largest influence (p = 0.057) because relative importance analysis demonstrated body mass to contribute to 43.87% of the variance (of the R2) in repetitions performed. No other variable was significant or approached significance (p > 0.05). Our results reveal that body mass, BF%, and femur length all are inversely related to repetitions performed at 70% of 1RM in the back squat.
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Historical Changes in Height, Mass and Age of USA Women’s Olympic Gymnastics Team: An UpdateSands, William A., Murray, Steven R., McNeal, Jeni R., Slater, Cindy, Stone, Michael H. 01 January 2018 (has links)
Nearly every modern Olympic Games has brought astonished comments and criticism of the body sizes of female gymnasts. The comments from laypersons, scientists, journalists, and physicians too often imply that these diminutive athletes are unusually small and possibly unhealthy. Purpose: An extended and updated analysis of the sizes of U.S. female Olympic gymnasts including the 2012 and 2016 Olympic Games. Methods: Official public records from the US Olympic Committee and USA Gymnastics of Olympic team members were assessed including height, mass, age, body-mass index (BMI) and team performance rankings. Sixteen Olympic teams with a total of 123 team positions including the alternates were assessed. Trend analyses were conducted using linear and polynomial models. Results: Analyses indicated that since 1956, height, mass, age, and BMI declined at first and then increased, with the exceptions of height and rank. Best regression fits were obtained via 2nd order polynomial equations. Height and rank showed a downward trend throughout the historical period. Conclusion: Female Olympic gymnasts were getting smaller through approximately the 1980s and early 1990s. An upward trend in size variables was then observed through 2008. The addition of the 2012 and 2016 Olympic Games data showed that height shifted to a decline from a slight upward trend, and rank continued to decline throughout the historical period.
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Reply to "Letter to the Editor: Comments on Stuart Et Al. (2016): 'myosin Content of Individual Human Muscle Fibers Isolated by Laser Capture Microdissection'"Stuart, Charles A., Brannon, Marianne F., Stone, William L., Stone, Michael H. 12 December 2016 (has links)
No description available.
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