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Case Study: Nutrition and Training Periodization in Three Elite Marathon Runners

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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Dietary Intake of Female Collegiate Heavyweight Rowers

Suzanne Nelson Steen, Kirsten Mayer, Kelly D. Brownell, and Thomas A. Wadden

The purpose of this study was to evaluate the adequacy of dietary intake in 16 female heavyweight rowers during the sprint racing phase of the season. Caloric intake for the rowers was 2,633 kcal/day, lower than expected given the training regimen of these athletes. On average, rowers consumed below-optimal levels of carbohydrate. Protein intake was satisfactory but fat intake was higher than recommended. For the majority of rowers, micronutrient intake met the RDA. However, calcium, zinc, B 6 , and B 12 fell short of meeting two-thirds of the RDA for a significant percentage of rowers. The preevent meal consumed both 15 hr and 2 hr before the event provided less carbohydrate and fluid but more fat than desirable. Female heavyweight rowers would benefit from nutritional counseling that provides strategies for increasing complex carbohydrates, calcium, zinc, B 6 , and B l2 while reducing dietary fat. Adequate fluid intake is also essential.

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The Effects of Red Bull Energy Drink Compared With Caffeine on Cycling Time-Trial Performance

Alannah Quinlivan, Christopher Irwin, Gary D. Grant, Sheilandra Anoopkumar-Dukie, Tina Skinner, Michael Leveritt, and Ben Desbrow

This study investigated the ergogenic effects of a commercial energy drink (Red Bull) or an equivalent dose of anhydrous caffeine in comparison with a noncaffeinated control beverage on cycling performance. Eleven trained male cyclists (31.7 ± 5.9 y 82.3 ± 6.1 kg, V̇O2max = 60.3 ± 7.8 mL · kg–1 · min–1) participated in a double-blind, placebo-controlled, crossover-design study involving 3 experimental conditions. Participants were randomly administered Red Bull (9.4 mL/kg body mass [BM] containing 3 mg/kg BM caffeine), anhydrous caffeine (3 mg/kg BM given in capsule form), or a placebo 90 min before commencing a time trial equivalent to 1 h cycling at 75% peak power output. Carbohydrate and fluid volumes were matched across all trials. Performance improved by 109 ± 153 s (2.8%, P = .039) after Red Bull compared with placebo and by 120 ± 172 s (3.1%, P = .043) after caffeine compared with placebo. No significant difference (P > .05) in performance time was detected between Red Bull and caffeine treatments. There was no significant difference (P > .05) in mean heart rate or rating of perceived exertion among the 3 treatments. This study demonstrated that a moderate dose of caffeine consumed as either Red Bull or in anhydrous form enhanced cycling time-trial performance. The ergogenic benefits of Red Bull energy drink are therefore most likely due to the effects of caffeine, with the other ingredients not likely to offer additional benefit.

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International Association of Athletics Federations Consensus Statement 2019: Nutrition for Athletics

Louise M. Burke, Linda M. Castell, Douglas J. Casa, Graeme L. Close, Ricardo J. S. Costa, Ben Desbrow, Shona L. Halson, Dana M. Lis, Anna K. Melin, Peter Peeling, Philo U. Saunders, Gary J. Slater, Jennifer Sygo, Oliver C. Witard, Stéphane Bermon, and Trent Stellingwerff

The International Association of Athletics Federations recognizes the importance of nutritional practices in optimizing an Athlete’s well-being and performance. Although Athletics encompasses a diverse range of track-and-field events with different performance determinants, there are common goals around nutritional support for adaptation to training, optimal performance for key events, and reducing the risk of injury and illness. Periodized guidelines can be provided for the appropriate type, amount, and timing of intake of food and fluids to promote optimal health and performance across different scenarios of training and competition. Some Athletes are at risk of relative energy deficiency in sport arising from a mismatch between energy intake and exercise energy expenditure. Competition nutrition strategies may involve pre-event, within-event, and between-event eating to address requirements for carbohydrate and fluid replacement. Although a “food first” policy should underpin an Athlete’s nutrition plan, there may be occasions for the judicious use of medical supplements to address nutrient deficiencies or sports foods that help the athlete to meet nutritional goals when it is impractical to eat food. Evidence-based supplements include caffeine, bicarbonate, beta-alanine, nitrate, and creatine; however, their value is specific to the characteristics of the event. Special considerations are needed for travel, challenging environments (e.g., heat and altitude); special populations (e.g., females, young and masters athletes); and restricted dietary choice (e.g., vegetarian). Ideally, each Athlete should develop a personalized, periodized, and practical nutrition plan via collaboration with their coach and accredited sports nutrition experts, to optimize their performance.

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Food and Fluid Intake and Disturbances in Gastrointestinal and Mental Function during an Ultramarathon

Beth Glace, Christine Murphy, and Malachy McHugh

The purpose of this study was to document eating strategies employed by runners during a 160-km race, and to identify eating patterns that predispose the runner to disturbed mental or gastrointestinal functioning. We monitored intake in 19 volunteers during the 12 hours pre-race. Intake was determined by interview with runners approximately every 12 km throughout the race. The mean finish time was 24.3 hours, with 4 runners not completing the race. Body mass decreased during the race, 75.9 ± 2.3 kg to 74.4 ± 2.2 kg (p < .001). Runners ingested 2643 kcals during the 12 hours prerace (68% carbohydrate) and 3.8 L of fluid. During the race 6047 kcal, 18 L of fluid, and 12 g of sodium were consumed. Gastrointestinal distress (GI) was experienced by half of the participants, but was unrelated to food or fluid intake. Upper GI symptoms were more prevalent than lower and occurred mainly after 88 km. Runners with GI distress tended to complete fewer training miles (p = .10) and to do shorter training runs (p = .08). Half of the volunteers reported mental status changes (MSC), such as confusion or dizziness. Runners with MSC had greater intake of total calories, carbohydrate, and fluid (p < .05) than runners without MSC. They also completed shorter training runs (p = .03). Caloric and moisture intake for all runners far exceeded intakes described previously. Although intake did not match energy expenditure, it may represent the upper limit for absorption during exercise, and very high food and/or fluid intake appears to lead to perturbed mental status.

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Case Study of a Female Ocean Racer: Prerace Preparation and Nutritional Intake During the Vendée Globe 2008

Deborah Fearnley, Louise Sutton, John O’Hara, Amy Brightmore, Roderick King, and Carlton Cooke

The Vendée Globe is a solo round-the-world sailing race without stopovers or assistance, a physically demanding challenge for which appropriate nutrition should maintain energy balance and ensure optimum performance. This is an account of prerace nutritional preparation with a professional and experienced female racer and assessment of daily nutritional intake (NI) during the race using a multimethod approach. A daily energy intake (EI) of 15.1 MJ/day was recommended for the race and negotiated down by the racer to 12.7 MJ/day, with carbohydrate and fluid intake goals of 480 g/day and 3,020 ml/day, respectively. Throughout the 99-day voyage, daily NI was recorded using electronic food diaries and inventories piloted during training races. NI was assessed and a postrace interview and questionnaire were used to evaluate the intervention. Fat mass (FM) and fat-free mass (FFM) were assessed pre- (37 days) and postrace (11 days) using dual-energy X-ray absorptiometry, and body mass was measured before the racer stepped on the yacht and immediately postrace. Mean EI was 9.2 MJ/day (2.4–14.3 MJ/day), representing a negative energy balance of 3.5 MJ/day under the negotiated EI goal, evidenced by a 7.9-kg loss of body mass (FM –7.5 kg, FFM –0.4 kg) during the voyage, with consequent underconsumption of carbohydrate by ~130 g/day. According to the postrace yacht food inventory, self-reported EI was underreported by 7%. This intervention demonstrates the practicality of the NI approach and assessment, but the racer’s nutrition strategy can be further improved to facilitate meeting more optimal NI goals for performance and health. It also shows that evaluation of NI is possible in this environment over prolonged periods, which can provide important information for optimizing nutritional strategies for ocean racing.

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Influence of Periodizing Dietary Carbohydrate on Iron Regulation and Immune Function in Elite Triathletes

Alannah K. A. McKay, Ida A. Heikura, Louise M. Burke, Peter Peeling, David B. Pyne, Rachel P.L. van Swelm, Coby M. Laarakkers, and Gregory R. Cox

adaptation: Too much of a good thing? European Journal of Sport Science, 15 ( 1 ), 3 – 12 . PubMed ID: 24942068 doi:10.1080/17461391.2014.920926 10.1080/17461391.2014.920926 Bishop , N.C. , Blannin , A.K. , Armstrong , E. , Rickman , M. , & Gleeson , M. ( 2000 ). Carbohydrate and fluid intake

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Abstracts From the December 2019 International Sport + Exercise Nutrition Conference in Newscastle upon Tyne

Izzicupo, G Galanti, A Pizzi, G Mascherini 15.15 Is it necessary to ingest carbohydrates and fluids during 10 km open water swimming in top-level competitions? G Olcina, R Timón, I González-Pérez Dietary Intake of Gaelic Football Players During Game Preparation and Recovery C Ó Catháin 1 , J Fleming 2 , M

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Got Beer? A Systematic Review of Beer and Exercise

Jaison L. Wynne and Patrick B. Wilson

). Consequently, preexercise alcoholic beer consumption is uncommon. Although alcoholic beer contains carbohydrate and fluid, the amount that would need to be consumed to meet standard preexercise recommendations for the intakes of these nutrients would be prohibitive. Whether nonalcoholic beer can serve as a

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Acute and Chronic Weight-Making Practice in Professional Mixed Martial Arts Athletes: An Analysis of 33 Athletes Across 80 Fights

Reid Reale, Junzhu Wang, Charles Hu Stull, Duncan French, Dean Amasinger, and Ran Wang

surprising and it is not clear why this cohort of athletes experienced lower weight regain. The only potential reason is that post-weigh-in nutrition strategies were not optimized given the available time frame. Indeed, increased recovery time and higher carbohydrate and fluid intake correlate with weight