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Brandon M. Kistler, Peter J. Fitschen, Sushant M. Ranadive, Bo Fernhall and Kenneth R. Wilund

The purpose of this study was to document the physiological changes that occur in a natural bodybuilder during prolonged contest preparation for a proqualifying contest. During the 26-week preparation, the athlete undertook a calorically restrictive diet with 2 days of elevated carbohydrate intake per week, increased cardiovascular (CV) training, and attempted to maintain resistance-training load. The athlete was weighed twice a week and body composition was measured monthly by DXA. At baseline and every 2 weeks following CV structure and function was measured using a combination of ultrasound, applanation tonometry, and heart rate variability (HRV). Cardiorespiratory performance was measured by VO2peak at baseline, 13 weeks, and 26 weeks. Body weight (88.6 to 73.3 Kg, R 2 = .99) and percent body fat (17.5 to 7.4%) were reduced during preparation. CV measurements including blood pressure (128/61 to 113/54mmHg), brachial pulse wave velocity (7.9 to 5.8m/s), and measures of wave reflection all improved. Indexed cardiac output was reduced (2.5 to 1.8L/m2) primarily due to a reduction in resting heart rate (71 to 44bpm), and despite an increase in ejection faction (57.9 to 63.9%). Assessment of HRV found a shift in the ratio of low to high frequency (209.2 to 30.9%). Absolute VO2 was minimally reduced despite weight loss resulting in an increase in relative VO2 (41.9 to 47.7ml/Kg). In general, this prolonged contest preparation technique helped the athlete to improve body composition and resulted in positive CV changes, suggesting that this method of contest preparation appears to be effective in natural male bodybuilders.

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Katrina Wynnyk and Nancy Spencer-Cavaliere

The purpose of this qualitative case study was to explore children with disabilities’ social relationships and motivation to take part in sledge hockey. Harter’s (1978) theory of Competence Motivation was used as the conceptual framework. Ten children (1 girl and 9 boys) between ages 11–16 years, who experienced a range of disabilities, participated. Primary data were collected using semistructured interviews, participant observations, and field and reflective notes. The thematic analysis led to four themes: (a) coach feedback, (b) parental involvement, (c) skill and belonging, and (d) (dis)ability sport. The findings revealed that interactions with significant others contributed extensively to the participant’s perceptions of competence and motivation to participate, as did the sport’s competitive nature. The findings are discussed in the context of Harter’s theory and the children’s sport and adapted physical activity inclusion literature.

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Catriona A. Burdon, Nathan A. Johnson, Phillip G. Chapman, Ahmad Munir Che Muhamed and Helen T. O’Connor

Purpose:

The aim of this study was to measure the effect of environmental conditions and aid-station beverage-cooling practices on the temperature of competitor beverages.

Methods:

Environmental and beverage temperatures were measured at three cycling and two run course aid stations at the 2010 Langkawi, Malaysia (MA), and Port Macquarie, Australia (AU), Ironman triathlon events. To measure the specific effect of radiant temperature, additional fluid-filled (600 ml) drink bottles (n = 12) were cooled overnight (C) and then placed in direct sun (n = 6) or shade (n = 6) near to a cycle aid station at AU.

Results:

During both events, beverage temperature increased over time (p < .05) as environmental conditions, particularly radiant temperature increased (p < .05). Mean beverage temperature ranged between 14–26°C and during both events was above the palatable range (15–22°C) for extended periods. At AU, bottles placed in direct sunlight heated faster (6.9 ± 2.3 °C·h−1) than those in the shade (4.8 ± 1.1°C·h−1, p = .05).

Conclusion:

Simple changes to Ironman aidstation practices, including shade and chilling beverages with ice, result in the provision of cooler beverages. Future studies should investigate whether provision of cool beverages at prolonged endurance events influences heat-illness incidence, beverage-consumption patterns, and competitor performance.

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Arnaud Faupin, Philippe Gorce, Eric Watelain, Christophe Meyer and Andre Thevenon

The aim of this study was to investigate muscle activity, kinematic, and handgrip-force pattern generation during handcycling. One able-bodied participant performed a 1-min exercise test on a handcycle at 70 revolutions per minute. This article proposes an original data collection and analysis methodology that gathers synchronized kinematics, kinetics, and electromyography. Such data, which most often appear complex, are easily summarized using this methodology. This preliminary study has an new setup and offers good indications on the biomechanical pattern for handcycling movement analysis.

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John S. Cuddy, Dustin R. Slivka, Walter S. Hailes, Charles L. Dumke and Brent C. Ruby

Purpose:

The purpose of this study was to determine the metabolic profile during the 2006 Ironman World Championship in Kailua-Kona, Hawaii.

Methods:

One recreational male triathlete completed the race in 10:40:16. Before the race, linear regression models were established from both laboratory and feld measures to estimate energy expenditure and substrate utilization. The subject was provided with an oral dose of 2H2 18O approximately 64 h before the race to calculate total energy expenditure (TEE) and water turnover with the doubly labeled water (DLW) technique. Body weight, blood sodium and hematocrit, and muscle glycogen (via muscle biopsy) were analyzed pre- and postrace.

Results:

The TEE from DLW and indirect calorimetry was similar: 37.3 MJ (8,926 kcal) and 37.8 MJ (9,029 kcal), respectively. Total body water turnover was 16.6 L, and body weight decreased 5.9 kg. Hematocrit increased from 46 to 51% PCV. Muscle glycogen decreased from 152 to 48 mmoL/kg wet weight pre- to postrace.

Conclusion:

These data demonstrate the unique physiological demands of the Ironman World Championship and should be considered by athletes and coaches to prepare sufficient nutritional and hydration plans.

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Richard N. Hinrichs

Ten male recreational runners ranging in age from 20 to 32 years were filmed using 3-D cinematography while running on a treadmill at 3.8 m/s, 4.5 m/ s, and 5.4 m/s. The 3-D segment endpoint data were entered into a computer program that computed the segmental contributions to the upward and forward propulsive impulses on the body (lift and drive, respectively) and to the vertical component of angular momentum (Hz). The results of two subjects who demonstrated asymmetrical arm action are discussed in detail and compared with the mean results computed over all subjects. The results revealed that the arms possess the potential to compensate for each other and for asymmetries elsewhere in the body.

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Thomas W. Rowland, Richard C. McFaul and David A. Burton

Syncope during sports participation may serve as the first manifestation of cardiovascular disease that poses a risk for athletic training and competition. Other causes of syncope (vasovagal, dehydration) during physical activity may be more benign. The athlete who faints during sports deserves a comprehensive diagnostic evaluation that addresses the wide-ranging differential diagnosis involved. The case of a 14-year-old male with two syncopal spells during athletic training is presented to review the components of such a workup and subsequent management implications.

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Lael Gershgoren, Edson Medeiros Filho, Gershon Tenenbaum and Robert J. Schinke

This study was aimed at capturing the components comprising shared mental models (SMM) and the training methods used to address SMM in one athletic program context. To meet this aim, two soccer coaches from the same collegiate program were interviewed and observed extensively during practices and games throughout the 2009–2010 season. In addition, documents (e.g., players’ positioning on free kicks sheet) from the soccer program were reviewed. The data were analyzed inductively through a thematic analysis to develop models that operationalize SMM through its components, and training. Game intelligence and game philosophy were the two main operational themes defining SMM. Moreover, four themes emerged for SMM training: (a) the setting, (b) compensatory communication, (c) reinforcement, and (d) instruction. SMM was embedded within a more comprehensive conceptual framework of team chemistry, including emotional, social, and cognitive dimensions. Implications of these conceptual frameworks are considered for sport psychologists and coaches.

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John Kenny, SarahJane Cullen and Giles D. Warrington

Purpose:

“Ice-mile” swimming presents significant physiological challenges and potential safety issues, but few data are available. This study examined deep body temperature (BT), respiratory rate (RR), and swim performance in 2 swimmers completing an ice-mile swim of 1 mile (1600 m) in water less than 5°C.

Methods:

Two male cold-water-habituated swimmers completed a 1-mile lake swim in 3.9°C water. For comparative purposes, they completed an indoor 1-mile swim in 28.1°C water. The Equivital physiological monitoring system was used to record BT and RR before, during, and after each swim. Total time to complete the swims and 400-m splits were recorded.

Results:

One swimmer became hypothermic after 27 min while swimming, reaching BT of 33.7°C at swim’s end. On exiting the water the swimmers experienced large BT after-drops of –3.6°C and –2.4°C, reaching low points of 33.2°C and 31.3°C 38 and 23 min postswim, respectively. Respiratory rate and swim pace decreased over the course of the ice-mile swim for both swimmers. Swim pace for 1 swimmer declined sharply in the final 400-m lap of the ice mile when he was hypothermic. Both swimmers remained hypothermic 60 min postswim (34.2°C and 33.4°C).

Conclusion:

Ice-mile swimmers may become hypothermic while swimming, and the postswim BT after drop may expose them to dangerous levels of hypothermia. Pace and RR should be monitored as proxies for a swimmer’s physiological state. Postswim recovery should also be monitored for hypothermia for at least 1 h.