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Alan J. McCubbin, Gregory R. Cox and Ricardo J.S. Costa

There is little information describing how endurance athletes perceive sodium intake in relation to training and competition. Using an online questionnaire, this study assessed the beliefs, information sources, and intended practices regarding sodium ingestion for training and competition. Endurance athletes (n = 344) from six English-speaking countries completed the questionnaire and were included for analysis. The most cited information sources were social supports (63%), self-experimentation (56%), and media (48%). Respondents generally believed (>50% on electronic visual analog scale) endurance athletes require additional sodium on a daily basis (median 67% [interquartile range: 40–81%]), benefit from increased sodium in the days preceding competition (60% [30–77%]), should replace sodium losses during training (69% [48–83%]) and competition (74% [54–87%]), and would benefit from sweat composition testing (82% [65–95%]). Respondents generally believed sodium ingestion during endurance exercise prevents exercise-associated muscle cramps (75% [60–88%]) and exercise-associated hyponatremia (74% [62–89%]). The majority (58%) planned to consciously increase sodium or total food intake (i.e., indirectly increasing sodium intake) in the days preceding competition. Most (79%) were conscious of sodium intake during competition, but only 29% could articulate a specific intake plan. A small minority (5%) reported using commercial sweat testing services, of which 75% believed it was beneficial. We conclude that endurance athletes commonly perceive sodium intake as important for their sporting activities. Many intend to consciously increase sodium intake in the days preceding and during competition, although these views appear informed mostly by nonscientific and/or non-evidence-based sources.

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Keith Baar

Patellar tendinopathy is one of the most common afflictions in jumping sports. This case study outlines the rehabilitation of a professional basketball player diagnosed by magnetic resonance imaging (MRI) with a central core patellar tendinopathy within the proximal enthesis. The player undertook a nutrition and strength-based rehabilitation program combining gelatin ingestion and heavy isometric loading of the patellar tendon designed to produce significant stress relaxation as part of their competition schedule and a whole-body training plan. On follow-up one and a half years into the program an independent orthopedic surgeon declared the tendon normal on MRI. Importantly, the improved MRI results were associated with a decrease in pain and improved performance. This case study provides evidence that a nutritional intervention combined with a rehabilitation program that uses stress relaxation can improve clinical outcomes in elite athletes.

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Stephanie K. Gaskell, Rhiannon M.J. Snipe and Ricardo J.S. Costa

Considering the recent growth of exercise gastroenterology research focusing on exercise-induced gastrointestinal syndrome mechanisms, response magnitude, prevention and management strategies, the standardized assessment of gastrointestinal symptoms (GIS) is warranted. The current methodological study aimed to test the reliability of a modified visual analog scale for assessing GIS during exercise, in response to a variety of exertional-stress scenarios, with and without dietary intervention. Recreational endurance runners (n = 31) performed one of the three exercise protocols, which included: 2-hr running at 70% V˙O2max in temperate (24.7 °C) ambient conditions, with fluid restriction; 2-hr running at 60% V˙O2max in hot (35.1 °C) ambient conditions, while consuming chilled water immediately before and every 15 min during exercise; and 2-hr running at 60% V˙O2max in temperate (23.0 °C) ambient conditions, while consuming 30 g/20 min carbohydrate (2∶1 glucose∶fructose, 10% temperate w/v), followed by a 1-hr distance test. GIS was monitored pre-exercise, periodically during exercise, and immediately postexercise. After wash out, participants were retested in mirrored conditions. No significant differences (p > .05) were identified between test–retest using Wilcoxon signed-rank test for all GIS (specific and categorized), within each exercise protocol and the combined protocols. Strong correlations were observed for gut discomfort, total GIS, upper GIS, and nausea (r s = .566 to r s = .686; p < .001), but not for lower GIS (r s = .204; p = .232). Cohen’s magnitude of difference was minimal for all GIS (specific δ < 0.14 and categorized δ < 0.08). The modified visual analog scale for assessing GIS during exercise appears to be a reliable tool for identifying incidence and severity of GIS in cohort populations and is sensitive enough to detect exertional and intervention differences.

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Hiroyuki Sagayama, Makiko Toguchi, Jun Yasukata, Kazunari Yonaha, Yasuki Higaki and Hiroaki Tanaka

Prior studies have examined offshore sailing and energy strategies using accurate total energy expenditure (TEE) measurement in free-living conditions. However, no research has studied energy and water requirements during dinghy class sailing such as an Olympic event with concentrated training. This study aimed to investigate the TEE, physical activity level (PAL), and water turnover (rH2O) of collegiate dinghy sailors in a training camp using the doubly labeled water method. Eleven dinghy sailing collegiate athletes (nine males and two females) participated. The doubly labeled water method was used to determine the participants’ TEE and PAL over 8 days (six training and two nontraining days). Participants trained approximately 7 hr/day on water. Body fat was measured using a stable isotope dilution method. The rH2O was estimated using deuterium turnover. The mean TEE, PAL, and rH2O were 17.30 ± 4.22 MJ/day (4,133 ± 1,009 kcal/day), 2.8 ± 0.3 (range: 2.1–4.1), and 3.3 ± 0.7 L/day (range: 2.6–4.5 L/day), respectively. To our knowledge, this was the first study to use the doubly labeled water method to determine TEE, PAL, and rH2O as references for competitive dinghy sailors in a spring training camp. Our results may serve as a reference to assist competitive dinghy sailors in determining their required nutritional support.

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Edgar J. Gallardo and Andrew R. Coggan

Consumption of beetroot juice (BRJ) supplements has become popular among athletes because beets tend to be rich in nitrate (NO3), which can enhance exercise performance by increasing nitric oxide production. The NO3 content of beets can vary significantly, however, making it difficult to know how much NO3 any product actually contains. Samples from 45 different lots of 24 different BRJ products from 21 different companies were therefore analyzed for NO3 (and nitrite [NO2]) concentration using high-performance liquid chromatography. The NO3 and NO2 content (i.e., amount per serving) was then calculated based on either (a) the manufacturer’s recommended serving size (for prepackaged/single dose products) or (b) as used in previous studies, a volume of 500 ml (for BRJ sold in bulk containers). There was moderate-to-large variability in NO3 content between samples of the same product, with a mean coefficient of variation of 30% ± 26% (range 2–83%). There was even greater variability between products, with a ∼50-fold range in NO3 content between the lowest and highest. Only five products consistently provided ≥5 mmol of NO3/serving, which seems to be the minimal dose required to enhance exercise performance in most individuals. NO2 contents were generally low (i.e., ≤0.5% compared with NO3), although two products contained 10% and 14%. The results of this study may be useful to athletes and their support staff contemplating which (if any) BRJ product to utilize. These data may also offer insight into variability in the literature with respect to the effects of BRJ on exercise performance.

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Pedro Figueiredo, George P. Nassis and João Brito

Purpose: To quantify the association between salivary secretory immunoglobulin A (sIgA) and training load in elite football players. Methods: Data were obtained on 4 consecutive days during the preparation camp for the Rio 2016 Olympic Games. Saliva samples of 18 elite male football players were collected prior to breakfast. The session rating of perceived exertion (s-RPE) and external training-load metrics from global positioning systems (GPS) were recorded. Within-subject correlation coefficients between training load and sIgA concentration, and magnitude of relationships, were calculated. Results: sIgA presented moderate to large negative correlations with s-RPE (r = −.39), total distance covered (r = −.55), accelerations (r = −.52), and decelerations (r = −.48). Trivial to small associations were detected between sIgA and distance covered per minute (r = .01), high-speed distance (r = −.23), and number of sprints (r = −.18). sIgA displayed a likely moderate decrease from day 1 to day 2 (d = −0.7) but increased on day 3 (d = 0.6). The training-load variables had moderate to very large rises from day 1 to day 2 (d = 0.7 to 3.2) but lowered from day 2 to day 3 (d = −5.0 to −0.4), except for distance per minute (d = 0.8) and sprints (unclear). On day 3, all training-load variables had small to large increments compared with day 1 (d = 0.4 to 1.5), except for accelerations (d = −0.8) and decelerations (unclear). Conclusions: In elite football, sIgA might be more responsive to training volume than to intensity. External load such as GPS-derived variables presented stronger association with sIgA than with s-RPE. sIgA can be used as an additional objective tool in monitoring football players.

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Rafael L. Kons, Kai Krabben, David L. Mann, Gabriela Fischer and Daniele Detanico

In judo competition for visual impairment, athletes of different classes compete against each other in the same category; B1 athletes are totally blind, whereas B2 and B3 athletes are partially sighted. To test for potential competition disparities due a single category of athletes, this study aimed to compare competitive and technical–tactical performance in visually impaired judo athletes with different degrees of visual impairment. The authors analyzed 340 judo matches from the 2012 and 2016 Paralympic Games. The scores, penalties, efficiency index, and types of medals were examined, as well as the technical variation and temporal structure. The main finding was that blind judo athletes presented lower scores (p < .05; effect size [ES] = 0.43–0.73), medals (p < .05), and efficiency (p < .05; ES = 0.40–0.73); different patterns of play; and a shorter time to lose than partially sighted athletes (p = .027; ES = 0.10–0.14). However, the penalties were similar between classes (p > .05; ES = 0.07–0.14). The odds ratio of a winning medal was 3.5–8 times less in blind athletes than in partially sighted athletes (p < .01). In conclusion, blind judo athletes presented lower competitive and technical–tactical performance than athletes with some residual functional vision. These findings provide support for the development of new evidence-based criteria for judo classification based on vision impairment.

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Rachael C. Stone, Shane N. Sweet, Marie-Josée Perrier, Tara MacDonald, Kathleen A. Martin Ginis and Amy E. Latimer-Cheung

Identifying as a regular exerciser has been found to effectively alter stereotypes related to warmth and competence for adults with a physical disability; however, it remains unclear how sport participation can influence this trend. Therefore, this study aimed to examine warmth and competence perceptions of adults with a physical disability portrayed as elite and nonelite athletes relative to other athletic and nonathletic subgroups of adults with and without a physical disability in the context of the stereotype content model. Using survey data from able-bodied participants (N = 302), cluster analyses were applied to a behaviors from intergroup affect and stereotypes map for displaying the intersection of warmth and competence perceptions. The results demonstrated that adults with a physical disability who are described as elite athletes (i.e., Paralympians) are clustered with high warmth and high competence, similar to their able-bodied athletic counterparts (i.e., Olympians). The findings suggest that perceiving athletic and elite sport statuses for adults with a physical disability may counter the stereotypes commonly applied to this group.

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Paul E. Yeatts, Ronald Davis, Jun Oh and Gwang-Yon Hwang

Participation in physical activity has been shown to improve components of psychological well-being (i.e., affect). Programs such as the Warrior Games have been designed to promote physical activity in wounded military personnel. However, sport competition typically yields a winner and a loser (i.e., game outcome). The experience of a win or a loss may affect how wounded athletes respond to game outcome. Therefore, the purpose of this study was to investigate the affective changes (positive affect, negative affect, tranquility, and fatigue) according to game outcome in a sample of wounded military wheelchair basketball players participating in a weekend tournament. The results indicated that the participants who experienced a win reported significantly higher positive affect and tranquility and significantly lower negative affect than those experiencing a loss. These findings have important implications for wounded veteran athletes, as well as coaches and administrative personnel.

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Mohsen Shafizadeh, Nicola Theis and Keith Davids

The aim of this study was to examine strategies to absorb impact shock during RaceRunning in participants with neurological motor disorders. For this purpose, 8 RaceRunning athletes (4 male and 4 female) voluntarily took part in the study. Each participant performed a series of 100-m sprints with a RaceRunning bike. Acceleration of the tibia and head was measured with 2 inertial measurement units and used to calculate foot-impact shock measures. Results showed that RaceRunning pattern was characterized by a lack of impact peak in foot–ground contact time and the existence of an active peak after foot contact. Due to the ergonomic properties of the RaceRunning bike, shock is attenuated throughout the stance phase. In conclusion, the results revealed that RaceRunning athletes with neurological motor disorders are capable of absorbing impact shock during assisted RaceRunning using a strategy that mimics runners without disabilities.