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Alan J. McCubbin, Gregory R. Cox and Elizabeth M. Broad

This case study describes the nutrition plans, intakes and experiences of five ultra-marathon runners who completed the Marathon des Sables in 2011 and 2013; age 37 (28–43) y, height 184 (180–190) cm, body mass 77.5 (71–85.5) kg, marathon personal best 3:08 (2:40–3:32). MdS is a 7-day, six-stage ultra-running stage race held in the Sahara Desert (total distance of timed stages 1–5 was 233.2 km in 2011, 223.4 km in 2013). Competitors are required to carry all equipment and food (except water) for the race duration, a minimum of 8,360 kJ/day and total pack weight of 6.5–15 kg. Total food mass carried was 4.2 (3.8–4.7) kg or 0.7 (0.5–1.1) kg/day. Planned energy (13,550 (10,323–18,142) kJ/day), protein (1.3 (0.8–1.8) g/kg/day), and carbohydrate (6.2 (4.3–9.2) g/kg/day) intakes on the fully self-sufficient days were slightly below guideline recommendations, due to the need to balance nutritional needs with food mass to be carried. Energy density was 1,636 (1,475–1,814) kJ/100g. 98.5% of the planned food was consumed. Fluid consumption was ad libitum with no symptoms or medical treatment required for dehydration or hyponatremia. During-stage carbohydrate intake was 42 (20–64) g/hour. Key issues encountered by runners included difficulty consuming foods due to dry mouth, and unpalatability of sweet foods (energy gels, sports drinks) when heated in the sun. Final classification of the runners ranged from 11th to 175th of 970 finishers in 2013, and 132nd of 805 in 2011. The described pattern of intake and macronutrient quantities were positively appraised by the five runners.

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Edward S. Potkanowicz

This case study was conducted as an attempt to quantify racecar-driver core body temperature and heart rate (HR) in real time on a minute-by-minute basis and to expand the volume of work in the area of driver science. Three drivers were observed during a 15-lap, 25-min maximal event. Each driver competed in the closed-wheel, closed-cockpit sports-car category. Data on core body temperature and HR were collected continuously using the HQ Inc. ingestible core probe system and HR monitoring. Driver 1 pre- and postrace core temperatures were 37.80°C and 38.79°C, respectively. Driver 2 pre- and postrace core temperatures were 37.41°C and 37.99°C. Driver 1 pre- and postrace HRs were 102 and 161 beats/min. Driver 2 pre- and postrace HRs were 94.3 and 142 beats/min. Driver 1’s physiological strain index (PSI) at the start was 3.51. Driver 2’s PSI at the start was 3.10. Driver 1 finished with a PSI of 7.04 and driver 2 with a PSI of 3.67. Results show that drivers are continuously challenged minute by minute. In addition, before getting into their cars, the drivers already experience physiological and thermal challenges. The data suggest that drivers are getting hot quickly. In longer events, this represents the potential for severe heat injury. Investigating whether the HRs observed are indicative of work or evidence of a thermoregulatory-associated challenge is a direction for future work. The findings support the value of real-time data collection and offer strong evidence for the expansion of research on driver-athletes.

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Jan Bourgois, Adelheid Steyaert and Jan Boone

Purpose:

In this case study, a world-class rower was followed over a period of 15 y in which he evolved from junior to professional athlete.

Methods:

An incremental exercise test and a 2000-m ergometer test were performed each year in the peak period of the season starting at the age of 16 y. In addition, the training logs of 1 y each as a junior and a senior rower were recorded and analyzed.

Results:

Maximal oxygen uptake (VO2max), maximal power output (Pmax), and power output at 4 mmol/L blood lactate concentration increased until the age of 27 and then stabilized at 30 y at 6.0 ± 0.2 L/min, 536 ± 15 W, and 404 ± 22 W, respectively. At the age of 27–28 y the rower also had a career-best 2000-m ergometer test (5′58″) and on-water performance with a 4th place at the Olympic Games (2008) in Beijing and World Championships (2009). At the age of 23 y, the rower trained a total of 6091 km in 48 wk. Of the total training time, 15.4% consisted of general training practices, 23.4% resistance training, and 61.2% specific rowing training.

Conclusion:

The on-water performance in the World Championships and Olympic Games corresponded closely to the evolution in the rower’s physiological profile and 2000-m ergometer performance. The long-term build-up program resulted in an increase in the physiological parameters up to the age of 27 y and resulted in a 4th position at the 2008 Olympic Games at a body mass of only 86 kg.

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Charles R. Pedlar, Gregory P. Whyte, Richard Burden, Brian Moore, Gill Horgan and Noel Pollock

This case study examines the impact of low serum ferritin (sFe) on physiological assessment measures and performance in a young female 1500-m runner undertaking approximately 95–130 km/wk training. The study spans 4 race seasons and an Olympic Games. During this period, 25 venous blood samples were analyzed for sFe and hemoglobin (Hb); running economy, VO2max, and lactate threshold were measured on 6 occasions separated by 8–10 mo. Training was carefully monitored including 65 monitored treadmill training runs (targeting an intensity associated with the onset of blood lactate accumulation) using blood lactate and heart rate. Performances at competitive track events were recorded. All data were compared longitudinally. Mean sFe was 24.5 ± 7.6 μg/L (range 10–47), appearing to be in gradual decline with the exception of 2 data points (37 and 47 μg/L) after parenteral iron injections before championships, when the lowest values tended to occur, coinciding with peak training volumes. Each season, 1500-m performance improved, from 4:12.8 in year 1 to 4:03.5 in year 4. VO2max (69.8 ± 2.0 mL · kg−1 · min−1) and running economy (%VO2max at a fixed speed of 16 km/h; max 87.8%, min 80.3%) were stable across time and lactate threshold improved (from 14 to 15.5 km/h). Evidence of anemia (Hb <12 g/dL) was absent. These unique data demonstrate that in 1 endurance athlete, performance can continue to improve despite an apparent iron deficiency. Raising training volume may have caused increased iron utilization; however, the effect of this on performance is unknown. Iron injections were effective in raising sFe in the short term but did not appear to affect the long-term pattern.

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Sarah Dempster, Rhiannon Britton, Andrew Murray and Ricardo J. S. Costa

The aims of this study were to assess the dietary intake and monitor self-reported recovery quality and clinical symptomology of a male ultra-endurance runner who completed a multiday ultra-endurance running challenge covering 4,254 km from North Scotland to the Moroccan Sahara desert over 78 consecutive days. Food and fluid intakes were recorded and analyzed through dietary analysis software. Body mass (BM) was determined before and after running each day, and before sleep. Clinical symptomology and perceived recovery quality were recorded each day. Whole blood hemoglobin and serum ferritin were determined before and after the challenge. Total daily energy (mean ± SD: 23.2 ± 3.2MJ·day−1) and macronutrient intake (182 ± 31g·day−1 protein, 842 ± 115g·day−1 carbohydrate, 159 ± 55 g·day−1 fat) met consensus nutritional guidelines for endurance performance. Total daily water intake through foods and fluids was 4.8 ± 2.0L·day−1. Water and carbohydrate intake rates during running were 239 ± 143ml·h−1 and 56 ± 19g·h−1, respectively. Immediately after running, carbohydrate and protein intakes were 1.3 ± 1.0g·kg BM−1 and 0.4 ± 0.2g·kg BM−1, respectively. Daily micronutrient intakes ranged from 109 to 662% of UK RNIs. Prerunning BM was generally maintained throughout. Overall exercise-induced BM loss averaged 0.8 ± 1.0%; although BM losses of ≥ 2% occurred in the latter stages, a reflection of the warmer climate. Varying degrees of self-reported perceived recovery quality and clinical symptomology occurred throughout the challenge. This case study highlights oscillations in dietary habits along 78 consecutive days of ultra-endurance running, dependent on changes in ambient conditions and course topography. Nevertheless, nutrition and hydration status were maintained throughout the challenge. Despite dietary iron intake above RNI and iron supplementation, this alone did not prevent deficiency symptoms.

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Karsten Koehler, Frank Huelsemann, Markus de Marees, Bjoern Braunstein, Hans Braun and Wilhelm Schaenzer

During prolonged periods of high energy expenditure (EE), restricted food intake can lead to a loss of body mass. This case study describes the preexpedition support for an unsupported 3-wk crossing of the Atacama Desert in Chile. The goals were to simulate the energy requirements of walking under varying conditions and to predict energy intake and EE to evaluate whether the expected weight loss was in acceptable limits. The expeditionist (male, 35 yr, 197 cm, basal weight 80 ± 0.5 kg) was a well-trained endurance athlete with experience of multiple expeditions. During the simulation, he walked on a treadmill at speeds of 2–7 km/hr under varying conditions of inclination (0%, 7.5%), backpack weight (0 kg, 30 kg), and altitude (sea level, simulated altitude of 3,500 m). Under all conditions, the lowest EE was observed at 5 km/hr. Based on the simulation data, we predicted an average EE of 4,944 kcal/day for the expedition. Because energy intake was restricted to 2,249 kcal/day, we expected the expeditionist to lose considerable weight and consequently advised him to gain 5 kg of body-fat reserves. During the actual desert crossing, he covered a distance of 26 ± 7 km/day at an average speed of 3.8 ± 0.4 km/hr. Daily EE (4,817 ± 794 kcal/day) exceeded energy intake (1,771 ± 685 kcal/day), and the negative energy balance was in agreement with the actual weight loss of 10.5 kg, which was most notable in the lower trunk.

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Trent Stellingwerff

Laboratory-based studies demonstrate that fueling (carbohydrate; CHO) and fluid strategies can enhance training adaptations and race-day performance in endurance athletes. Thus, the aim of this case study was to characterize several periodized training and nutrition approaches leading to individualized race-day fluid and fueling plans for 3 elite male marathoners. The athletes kept detailed training logs on training volume, pace, and subjective ratings of perceived exertion (RPE) for each training session over 16 wk before race day. Training impulse/load calculations (TRIMP; min × RPE = load [arbitrary units; AU]) and 2 central nutritional techniques were implemented: periodic low-CHO-availability training and individualized CHO- and fluidintake assessments. Athletes averaged ~13 training sessions per week for a total average training volume of 182 km/wk and peak volume of 231 km/wk. Weekly TRIMP peaked at 4,437 AU (Wk 9), with a low of 1,887 AU (Wk 16) and an average of 3,082 ± 646 AU. Of the 606 total training sessions, ~74%, 11%, and 15% were completed at an intensity in Zone 1 (very easy to somewhat hard), Zone 2 (at lactate threshold) and Zone 3 (very hard to maximal), respectively. There were 2.5 ± 2.3 low-CHO-availability training bouts per week. On race day athletes consumed 61 ± 15 g CHO in 604 ± 156 ml/hr (10.1% ± 0.3% CHO solution) in the following format: ~15 g CHO in ~150 ml every ~15 min of racing. Their resultant marathon times were 2:11:23, 2:12:39 (both personal bests), and 2:16:17 (a marathon debut). Taken together, these periodized training and nutrition approaches were successfully applied to elite marathoners in training and competition.

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Andrew Pardue, Eric T. Trexler and Lisa K. Sprod

Extreme body composition demands of competitive bodybuilding have been associated with unfavorable physiological changes, including alterations in metabolic rate and endocrine profile. The current case study evaluated the effects of contest preparation (8 months), followed by recovery (5 months), on a competitive drug-free male bodybuilder over 13 months (M1-M13). Serum testosterone, triiodothyronine (T3), thyroxine (T4), cortisol, leptin, and ghrelin were measured throughout the study. Body composition (BodPod, dualenergy x-ray absorptiometry [DXA]), anaerobic power (Wingate test), and resting metabolic rate (RMR) were assessed monthly. Sleep was assessed monthly via the Pittsburgh Sleep Quality Index (PSQI) and actigraphy. From M1 to M8, testosterone (623–173 ng∙dL-1), T3 (123–40 ng∙dL-1), and T4 (5.8–4.1 mg∙dL-1) decreased, while cortisol (25.2–26.5 mg∙dL-1) and ghrelin (383–822 pg∙mL-1) increased. The participant lost 9.1 kg before competition as typical energy intake dropped from 3,860 to 1,724 kcal∙day-1; BodPod estimates of body fat percentage were 13.4% at M1, 9.6% at M8, and 14.9% at M13; DXA estimates were 13.8%, 5.1%, and 13.8%, respectively. Peak anaerobic power (753.0 to 536.5 Watts) and RMR (107.2% of predicted to 81.2% of predicted) also decreased throughout preparation. Subjective sleep quality decreased from M1 to M8, but objective measures indicated minimal change. By M13, physiological changes were largely, but not entirely, reversed. Contest preparation may yield transient, unfavorable changes in endocrine profile, power output, RMR, and subjective sleep outcomes. Research with larger samples must identify strategies that minimize unfavorable adaptations and facilitate recovery following competition.

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Edson Filho, Lael Gershgoren, Itay Basevitch, Robert Schinke and Gershon Tenenbaum

The present study was an initial attempt to capture and describe instances of shared mental models within a team from the point of view of the team captain. Specifically, the purpose of this study was to describe a range of perceived and shared behaviors aimed at facilitating the overall performance of a college volleyball team from the perspective of the team captain. This behavioral focus is congruent with the need for documenting observable task and team-related coordination mechanisms. Symbolic interactionism, via the use of systematic observations, documental analysis, and semistructured open-ended interviews, was used to gather data from the participant in the form of a case study. Data were analyzed using Braun and Clarke’s (2006) theoretical thematic analysis based on categories derived from Eccles and Tenenbaum’s (2004) Conceptual Framework of Coordination in Sport Teams. Results indicated that the player’s actions were perceived as enhancing proactive information sharing within her team. Therefore, it is suggested that team leaders possess important objective and symbolic roles in the promotion of shared mental models. These results are further discussed in relation to current knowledge of shared mental models in sports. Limitations and directions for future research are outlined.

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Jamie B. Barker and Marc V. Jones

This study reports the effects of a hypnosis intervention on a professional soccer player who reported low self-efficacy and a negative mood state relative to his soccer performance. Pre- and postintervention data were collected via a Soccer Self-Efficacy Questionnaire (SSEQ) that consisted of 10 items relating to good soccer performance, the Trait Sport Confidence Inventory (TSCI), the Positive and Negative Affect Schedule (PANAS), and a Soccer Performance Measure (SPM). An intervention program consisting of eight hypnosis sessions was conducted. These sessions comprised the presentation of ego-strengthening suggestions. Both visual and statistical analysis revealed substantial increases in trait sport confidence, self-efficacy, positive affect, and soccer performance, as well as a substantial decrease in negative affect over the course of the intervention. The findings of this case study suggest that hypnosis can be used to enhance self-efficacy, affect, and sport performance. A number of practical issues are presented surrounding the use of hypnosis in the context of English soccer and with athletes in general.