Table 3.
Nutrition-related adverse outcomes in competitions and endurance and ultra-endurance sports, investigated in case studies.
| Study | Objectives | Sample | Sporting Competition | Adverse Outcomes | Incidence | Causes | Conclusions |
|---|---|---|---|---|---|---|---|
| Gomm et al. (2016) [44] | To demonstrate the effectiveness and safety of a portable medical device for chilling that acts on the endothermic surface. | 3 M | 2 marathons, UK. (2015) | EHS and other, related problems. | EHS: 3 cases (100%) Vomiting: 1 case (33.3%) |
Environmental conditions during the competitions. | -The basis of the treatment is rapid attention and cooling; the fastest cooling rates were with water and ice baths. This reduced complications, being associated with a better long-term prognosis. |
| Six et al. (2016) [8] | To identify the source of infection and document the reach of an outbreak of acute gastroenteritis that occurred during an obstacle adventure race. | 729 athletes -332 F -397 M |
Obstacle adventure race (13 km, 22 obstacles), France. (2015) | GI illnesses. | Acute gastroenteritis: 375 cases (50.3%) | Person to person transmission of a norovirus, the source of which was contaminated sewage sludge. | -A series of recommendations should be proposed to reduce the risk of infection among athletes in this type of event. -The runners in and organizers of these events should be aware of the possible risks involved in accidental ingestion of dirty water, avoiding areas contaminated by animal feces. |
| Carvalho et al. (2016) [45] | Identification, diagnosis, and evolution of an athlete who suffered from EHS together with other medical complications during a marathon. | 1 M | Marathon (the subject only completed 16 km), Portugal. (2016) | EHS and related complications. | EHS: 1 case (100%) Hypoglycemia: 1 case (100%) |
Climatic changes and certain non-prescribed medicines could have been the causes. | -The athlete was cooled down in the hospital emergency department after only a few hours of the EHS, which may have contributed to the good outcome and recovery. -This works shows the importance of identifying risk factors, such as intake of medications that affect heat dissipation (antihistamines, anticholinergics, or calcium antagonists), sleep deprivation, and DH. |
| Smith et al. (2016) [14] | Analysis of the case of monozygotic twins that collapsed after EHS and during the same event, in relatively cold weather. | 2 M Monozygotic twins | 35-km race, UK. (2016) | EHS. | EHS: 2 cases (100%) | Causes unknown; the subjects denied sleep deprivation and felt hydrated before the start of the race. | -The development of EHS is multifactorial; however, the combination of the responsibilities of the pace of the race, the additional resistance of the backpack weight, and a genetic predisposition are likely to have played an important role. |
| Roberts et al. (2016) [46] | -Analysis of the case of an athlete who collapsed in two different marathons due to EHS and did not finish either races. -To study a simulation of the return to physical activity, to avoid repeating the circumstances of previous competitions. |
1 M | Two marathons, 6 weeks apart. The athlete dropped out of both after 20 km. USA. (2009) | EHS. | EHS: 1 case (100%) | Genetic causes of the EHS were discounted and an inadequate heat tolerance during these competitions was considered as the possible cause. | -The challenge of achieving an adequate hydro-electrolytic balance increases the risk of suffering from EHS during these competitions. -A quick response of spectators and colleagues, to ask for medical help, is crucial to reduce the risks associated with EHS. -To ensure a successful completion of these events, adequate heat tolerance should be guaranteed, as runners may be susceptible to EHS in cold conditions. |
| Myers et al. (2015) [47] | -To demonstrate the diagnostic challenges and the importance of proper management in cases of EAH. -To confirm that treatment with high volumes of an isotonic solution may delay recovery and may even lead to death. |
1 F | Hiking in the Grand Canyon National Park, approximately 10 km, USA (2008) | EAH and other, related problems. | EAH: 1 case (100%) -Vomiting: 1 case (100%) |
Overhydration combined with fluid retention caused by the secretion of arginine-vasopressin. | -The first symptoms of EAH include nausea, vomiting, and headache, which progress rapidly to confusion, altered mental status, seizures, and death if not treated in time. -The recognition of EAH and its treatment with hypertonic saline solution is a safe and effective option. In addition, for sporting events that take place in areas with a desert climate, it would be beneficial to have sodium detection tests and to be able to administer hypertonic saline solutions |
| Severac et al. (2014) [48] | -To analyze the case of an athlete that, after completing an Ironman event, went to the emergency department with a headache, nausea, and confusion. -To study the causes that triggered the EAH. |
1 F | Ironman, France (2012) | EAH and other, related problems. | EAH: 1 case (100%) -Nausea: 1 case (100%) |
-Excess fluid consumption compared to the losses of body fluids. | -EAH remains a complication with few diagnoses in endurance sports. In more severe cases, a correct and timely treatment allows complete neurological recovery. -Risk factors have been identified, such as: female sex, use of anti-inflammatories and diuretics, excessively cold or hot weather, the duration and intensity of the event, and excessive fluid intake |
| Hostler et al. (2014) [49] | To analyze the case of a half-marathon athlete that suffered EHS during a race in relatively mild conditions and compare it with cases of other runners who also suffered EHS in similar climatic conditions. | 1 M | Half-marathon, USA. (2012) | EHS. | EHS: 1 case (100%) | -The climatic conditions in an urban stretch of direct sunlight near the finish line. | -EHS requires active cooling therapy but this is rare during a half-marathon; however, EHS can occur even in relatively mild conditions. -The climatic conditions must be directly monitored at multiple points throughout the race, since it is possible for the temperature to be estimated in a single place that is not representative of the heat load on the participants |
| Bhangu et al. (2010) [50] | -To evaluate if body temperature contributed to the abandonment of an event by competitors. -To evaluate the agreement between the measurements made using oral and tympanic thermometers. |
4700 athletes | “Adventure raid”: an open-air event incorporating climbing, swimming, rafting. United Kingdom. (2009) | HT. | HT: 64 cases (1.4%) | -The climatic conditions and the swimming stages contributed to a decline in body temperature of the participants. | -The diagnosis of the doctors did not always coincide with the data obtained using the thermometers, regarding the existence of hypothermia or not in the runners. -The values of the tympanic and oral thermometers had little agreement. |
| Castro et al. (2009) [51] | To address the risks of HT and hypoglycemia during an open-water swimming competition, to alert doctors about the potential dangers of this type of competition |
12 athletes -5 F -7 M |
Official open-water swimming competition (10 km), Brazil. (2008) | HT and hypoglycemia. | HT: 10 cases (83%) Hypoglycemia: 0 cases (all but one of the athletes received several doses of maltodextrin) |
-Exposure to water for a prolonged period (at least two hours), contributing to the reduction of body temperature. | -HT is a common phenomenon, even in swimmers competing in relatively warm water. Therefore, it could be an important medical concern in such events. -The measurement of body temperature should be a key factor during competitions with these characteristics. |
| Rae et al. (2008) [52] | To determine why only 4 of the 35,627 athletes competing in cycling races were hospitalized by EHS, and whether the exercise alone could have raised their body temperature enough to cause EHS. | 4 M | 3 cyclists that participated in races, completing 80–109 km, died shortly after, South Africa. (2002) Another athlete, who completed 56 km in the “Two Oceans” marathon, South Africa. (2006) |
EHS and other, related problems. | EHS: 4 cases (100%) -Vomiting: 2 cases (50%) -EAH: 1 case (25%) |
-High rates of heat production in unfavorable environmental conditions caused a progressive build-up of body heat. | -The HT of the cases studied may have been the result of failure in the heat-loss mechanisms. -These cases could have been due to excessive endothermia, triggered by physical exertion. A correct diagnosis of excessive endothermia in cases of heat stroke in mild to moderate environmental conditions and the immediate initiation of cooling in all cases of EHS are crucial. |
F = female; M = male; GI: gastrointestinal; EAH: exercise-associated hyponatremia; EHS: heat stroke by exertion; DH: dehydration; HT: hypothermia.