46 research outputs found
Association of Gastrointestinal Distress in Ultramarathoners with Race Diet
Context: Gastrointestinal (GI) distress is common during ultrarunning.
Purpose: To determine if race diet is related to GI distress in a 161-km ultramarathon.
Methods: Fifteen (10 male, 5 female) consenting runners in the Javelina Jundred (6.5 loops on a desert trail) participated. Body mass was measured immediately pre-race and after each loop. Runners reported if they had nausea, vomiting, abdominal cramps, and/or diarrhea after each loop. Subjects were interviewed after each loop to record food, fluid, and electrolyte consumption. Race diets were analyzed using Nutritionist Pro.
Results: Nine (8 male, 1 female) of 15 runners experienced GI distress including nausea (89%), abdominal cramps (44%), diarrhea (44%), and vomiting (22%). Fluid consumption rate was higher (p = .001) in runners without GI distress (10.9 ± 3.2 ml · kg–1 · hr–1) than in those with GI distress (5.9 ± 1.6 ml · kg–1 · hr–1). Runners without GI distress consumed a higher percentage fat (p = .03) than runners with GI distress (16.5 ± 2.6 vs. 11.1 ± 5.0). In addition, fat intake rate was higher (p = .01) in runners without GI distress (0.06 ± 0.03 g · kg–1 · hr–1) than in runners with GI distress (0.03 ± 0.01 g · kg–1 · hr–1). Lower fluid and fat intake rates were evident in those developing GI distress before the onset of symptoms.
Conclusions: A race diet with higher percentage fat and higher intake rates of fat and fluid may protect ultramarathoners from GI distress. However, these associations do not indicate cause and effect, and factors other than race diet may have contributed to GI distress
Bone: An Acute Buffer of Plasma Sodium during Exhaustive Exercise?
Both hyponatremia and osteopenia separately have been well documented in endurance athletes. Although bone has been shown to act as a “sodium reservoir” to buffer severe plasma sodium derangements in animals, recent data have suggested a similar function in humans. We aimed to explore if acute changes in bone mineral content were associated with changes in plasma sodium concentration in runners participating in a 161 km mountain footrace. Eighteen runners were recruited. Runners were tested immediately pre- and post-race for the following main outcome measures: bone mineral content (BMC) and density (BMD) via dual-energy X-ray absorptiometry (DEXA); plasma sodium concentration ([Na+]p), plasma arginine vasopressin ([AVP]p), serum aldosterone concentration ([aldosterone]s), and total sodium intake. Six subjects finished the race in a mean time of 27.0±2.3 h. All subjects started and finished the race with [Na+]p within the normal range (137.7±2.3 and 136.7±1.6 mEq/l, pre- and post-race, respectively). Positive correlations were noted between change (Δ; post-race minus pre-race) in total BMC (grams) and [Na+]p (mEq/l) (r=0.99;
Drinking during marathon running in extreme heat: A video analysis study of the top finishers in the 2004 Athens Olympic marathons
Objective. To assess the drinking behaviours of top competitors during an Olympic marathon. Methods. Retrospective video analysis of the top four finishers in both the male and female 2004 Athens Olympic marathons plus the pre-race favourite in the female race in order to assess total time spent drinking. One male and female runner involved in a laboratory drinking simulation trial. Results. For the five female athletes, 37 of a possible 73 drinking episodes were captured. The female race winner was filmed at 11 of 15 drinking stations. Her total drinking time was 23.6 seconds; extrapolated over 15 seconds this would have increased to 32.2 seconds for a total of 27 sips of fluid during the race. Eighteen of a possible 60 drinking episodes for the top four male marathon finishers were filmed. The total drinking time for those 18 episodes was 11.4 seconds. A laboratory simulation found that a female athlete of approximately the same weight as the female Olympic winner might have been able to ingest a maximum of 810 ml (350 ml.h-1) from 27 sips whilst running at her best marathon pace whereas a male might have drunk a maximum of 720 ml (330 ml.h-1) from 9 sips under the same conditions. Conclusions. These data suggest that both the female and male 2004 Olympic Marathon winners drank minimal total amounts of fluid (30ÂşC) temperatures while completing the marathon with race times within 2.5% of the Olympic record
Hyponatremia in the 2009 161-km Western States Endurance Run
Purpose:To determine the incidence of exercise-associated hyponatremia (EAH), the associated biochemical measurements and risk factors for EAH, and whether there is an association between postrace blood sodium concentration ([Na+]) and changes in body mass among participants in the 2009 Western States Endurance Run, a 161-km mountain trail run.
Methods: Change in body mass, postrace [Na+], and blood creatine phosphokinase (CPK) concentration, and selected runner characteristics were evaluated among consenting competitors.
Results: Of the 47 study participants, 14 (30%) had EAH as defined by a postrace [Na+] /L. Postrace [Na+] and percent change in body mass were directly related (r = .30, P = .044), and 50% of those with EAH had body mass losses of 3–6%. EAH was unrelated to age, sex, finish time, or use of nonsteroidal anti-inflammatory drugs during the run, but those with EAH had completed a smaller (P = .03) number of 161-km ultramarathons. The relationship of CPK levels to postrace [Na+] did not reach statistical significance (r = –.25, P = .097).
Conclusions: EAH was common (30%) among finishers of this 161-km ultramarathon and it was not unusual for those with EAH to be dehydrated. As such, changes in body mass should not be relied upon in the assessment for EAH during 161-km ultramarathons
Depression in Collegiate Runners and Soccer Players: Relationships with Serum 25-Hydroxyvitamin D, Ferritin and Fractures
International Journal of Exercise Science 14(5): 1099-1111, 2021. The main purpose of this study was to evaluate relationships between depression versus serum 25-hydroxyvitamin D (vitamin D), serum ferritin (ferritin), and fractures across a competitive season. The authors conducted a prospective observational study (both pre- and post-season testing) on 51 collegiate soccer and cross-country athletes from a Midwest University. Our main outcome measure was depression, measured using the Center for Epidemiological Studies Depression Scale (CES-D). A CES-D score ≥ 16 represented the threshold value for clinical depression. Secondary outcome variables included vitamin D, ferritin, and fractures. Two athletes (3.9%; one female) pre-season while seven athletes (13.7%; five females) post-season demonstrated clinically relevant depression (CES-D score ≥ 16). Depression scores increased from pre- to post-season (6.0 to 8.9; p = 0.009; effect size = 0.53; n = 51). A medium effect noted for depressed athletes vs. non-depressed athletes (n = 7; post-season) to have lower pre-season serum vitamin D (38.4 vs. 50.2 ng/ml; p = 0.15; effect size = 0.68) with a small overall correlation effect (r = -0.08; p = 0.58). A medium correlation effect was noted between post-season ferritin vs. depression scores (r = -0.45; p = 0.01) in the female cohort only. Six athletes (11.8%) sustained fractures and had lower depression scores vs. non-injured athletes (4 vs. 10; p = 0.04; effect size = 1.08) post-season. Depression scores increased over a competitive season, especially in females. Small correlation effects were observed between depression and vitamin D. A medium correlation effect was noted between depression and low ferritin levels, in female athletes only. A large effect was noted between athletes sustaining fractures during the season and depression, post-season, with injured athletes being less depressed than non-injured athletes
Avoid adding insult to injury - correct management of sick female endurance athletes
Objectives. To evaluate the efficacy of Ringer’s lactate, isotonic saline and hypertonic saline on the clinical and biochemical recovery of athletes with exercise-associated hyponatraemic encephalopathy caused by fluid overload.
Methods. We retrospectively reviewed serial blood sodium concentrations (Na+) and qualitative signs of recovery and time to recovery in two healthy menstruant females hospitalised with dilutional exercise-associated hyponatraemic encephalopathy after withdrawal from the 2011 Comrades Marathon (89 km) and Argus Cycle Tour (109 km).
Results. Improvements in blood Na+ did not occur with intravenous administration of Ringer’s lactate solution, but did occur with administration of isotonic and hypertonic saline. Qualitative improvements in mental status were not quantitatively related to the biochemical value of blood Na+ or subsequent return to normonatraemia.
Conclusions. Hyponatraemia should be suspected in all female athletes presenting to the medical area of endurance races with vomiting, altered mental status and a history of high fluid intake. If a diagnosis of exercise-associated hyponatraemia with cerebral encephalopathy is confirmed, the treatment of choice is administration of an intravenous bolus of hypertonic saline. Administration of Ringer’s lactate should be discouraged, as this does not correct Na+ and appears to delay recovery
Acute renal failure in four Comrades Marathon runners ingesting the same electrolyte supplement: Coincidence or causation?
Objectives. To evaluate common factors associated in the development of acute renal failure (ARF) in Comrades Marathon runners.
Methods. This was a retrospective case series of 4 runners hospitalised post-race with ARF in the 89 km 2010 Comrades Marathon. The outcome measures were incidence of analgesic use, levels of creatine phosphokinase (CPK) and degree of electrolyte supplementation (sodium, potassium, calcium and magnesium).
Results. The incidence of ARF was 1/4 125 runners. They presented with rhabdomyolysis (mean admission CPK of 36 294 IU) and hyponatraemia (mean admission blood sodium level of 133 mEq/l). All had ingested an analgesic during the run (3 ingested a non-steroidal anti-inflammatory drug) and the same readily available anti-cramp electrolyte supplement. The average amount of supplemental sodium (452 mg), potassium (393 mg), calcium (330 mg) and magnesium (154 mg) ingested via this particular electrolyte supplement before and during the run did not exceed the recommended upper limits of daily intake. Three of the runners were Comrades Marathon novices.
Conclusions. There is a continuing need to clarify the specific cluster variants that cause ARF in Comrades Marathon runners, as the risk factors appear to have evolved since the first case described over 40 years ago
Longitudinal Changes in Fat and Lean Mass: Comparisons between 3D-Infrared and Dual-Energy X-ray Absorptiometry Scans in Athletes
International Journal of Exercise Science 15(4): 1587-1599, 2022. The low cost and portability of three-dimensional (3D) infrared body scanners make them an attractive tool for body composition measurement in athletes. The main purpose of this study was to compare total body fat percentage (BF%) and total lean mass (LM in kg), in a cohort of collegiate athletes, using a 3D infrared body scanner versus a dual energy x-ray absorptiometry (DXA) scanner. Phase I was a pre-season cross-sectional analysis of 61 (39 male) athletes while Phase II was a longitudinal subset analysis of 38 (27 male) student-athletes who returned to the laboratory for post-season scans (Post minus pre-season change). Both the 3D and DXA scans were performed within 20-minutes of one another in the same room, wearing the same clothing. Paired t-tests were used to compare the mean values (BF% and LM) between measurement devices with estimated effects size calculated using Cohen’s d. Data reported as mean±SD. Mean difference (DXA minus 3D) in LM were significantly higher using the 3D scan (5.84 ± 3.55kg; p \u3c 0.001; d = 0.90) compared to the DXA scan, while significantly underestimating BF% (-4.57 ± 4.67%; p \u3c 0.001; d = 1.6) in Phase I analyses. In Phase II analyses, significant differences in the change (post-season minus pre-season change) values were found between methods for LM (4.45 ± 5.04; p \u3c 0.001; d = 0.90), while BF% (-0.41 ± 2.06; p= 0.223; d = 0.2) showed no significant differences. In summary, the 3D and DXA scan values for LM and BF% were not interchangeable in cross-sectional nor longitudinal body composition analyses in collegiate athletes. Close agreement was only observed in longitudinal analyses of BF% and requires further validation with larger cohorts
Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015
The third International Exercise-Associated Hyponatremia (EAH) Consensus Development Conference convened in Carlsbad, California in February 2015 with a panel of 17 international experts. The delegates represented 4 countries and 9 medical and scientific sub-specialties pertaining to athletic training, exercise physiology, sports medicine, water/sodium metabolism, and body fluid homeostasis. The primary goal of the panel was to review the existing data on EAH and update the 2008 Consensus Statement.1 This document serves to replace the second International EAH Consensus Development Conference Statement and launch an educational campaign designed to address the morbidity and mortality associated with a preventable and treatable fluid imbalance.
The following statement is a summary of the data synthesized by the 2015 EAH Consensus Panel and represents an evolution of the most current knowledge on EAH. This document will summarize the most current information on the prevalence, etiology, diagnosis, treatment and prevention of EAH for medical personnel, athletes, athletic trainers, and the greater public. The EAH Consensus Panel strove to clearly articulate what we agreed upon, did not agree upon, and did not know, including minority viewpoints that were supported by clinical experience and experimental data. Further updates will be necessary to both: (1) remain current with our understanding and (2) critically assess the effectiveness of our present recommendations. Suggestions for future research and educational strategies to reduce the incidence and prevalence of EAH are provided at the end of the document as well as areas of controversy that remain in this topic. [excerpt