Effect of an intense period of competition on race performance and self‐reported illness in elite cross‐country skiers

Abstract

Effect of an intense period of competition on race performance and self-reported illness in elite cross-country skiers.This item was submitted to Loughborough University's Institutional Repository by the/an author. affects subsequent illness incidence, training and race performance. Methods: Selfreported training and illness data from 44 male and female elite cross-country skiers were included. In total, 125 years' of data was collected (2-3 seasons per athlete).Illness incidence, training load and performance in international competitions were calculated for athletes who did and did not participate in TDS. Results: 48% of athletes reported becoming ill during or in the days immediately after taking part in TDS, vs. 16%of athletes who did not participate. In both groups, illness incidence was somewhat lower for female athletes. For male athletes, race performance was significantly worse for 6 weeks following TDS vs. 6 weeks before TDS. Furthermore, while female athletes who participated in TDS performed relatively better than controls in Olympics/WorldChampionships, male athletes who participated in TDS typically performed worse in subsequent major championships. Conclusion: Participating in TDS appears to result in ~3-fold increase in risk of illness in this period. Male athletes appear more prone to illness and also see a drop in race performance following TDS, possibly linked to differences in training load before and after the event.3

How much is too much? (Part 2) International Olympic Committee consensus statement on load in sport and risk of illness

“…23 In another study, elite cross-country skiers participating in an 11-day ski tour had a higher incidence of illness compared with skiers not participating in the tournament. 85 Finally, competition was an independent risk factor for illness (odds ratio for illness=2.9) in a group of elite cross-country skiers that were followed over a 7-8 years period. 3 In summary, the current data indicate that participation in competitions (single or multiple) is associated with an increased risk of illness, but there are too few data to quantify that risk and this requires further investigation.…”

Immune nutrition and exercise: Narrative review and practical recommendations

“…Nevertheless, although elite athletes may not experience a greater annual incidence rate of infections, there is increasing recognition that episodes of upper-respiratory symptoms (URS) typically cluster around intense periods of training (Hellard, Avalos, Guimaraes, Toussaint & Pyne, 2015;Moreira, Delgado, Moreira & Haahtela, 2009;Svendsen, Gleeson, Haugen & Tønnessen, 2015;Svendsen et al, 2016) with a greater risk during winter months (Hellard et al, 2015;Spence et al, 2007).…”

Immunological aspects of sport nutrition

“…Athletes who engage in intense training or who have recently competed in endurance race events appear to be at increased risk of developing symptoms of minor upper respiratory illness symptoms (URS) [1][2][3][4][5] . The most common illnesses in athletes are viral infections of the upper respiratory tract (i.e.…”

“…Athletes who engage in intense training or who have recently competed in endurance race events appear to be at increased risk of developing symptoms of minor upper respiratory illness symptoms (URS). [1][2][3][4][5] The most common illnesses in athletes are viral infections of the upper respiratory tract (that is, the common cold), but athletes can also develop similar symptoms (for example, sore throat) due to allergy or inflammation caused by inhalation of cold, dry or polluted air. 6 In themselves, these URS have generally trivial consequences, but importantly to the elite athlete they can disrupt training, cause underperformance or even require withdrawal from competition.…”

“…Prolonged bouts of vigorous exercise have been shown to result in transient depression of several white blood cell (leukocyte) functions and it is suggested that such changes create an 'open window' of diminished host protection, during which viruses and bacteria can gain a foothold, increasing the risk that infection symptoms will develop. 5 Other factors such as competition 3,4 and psychological stress, lack of sleep, 7 exposure to environmental extremes (for example, altitude) and malnutrition can also depress immunity 8,9 and lead to increased risk of infection ( Figure 1). There are also some situations in which an athlete's exposure to infectious agents may be increased-this is the other important determinant of infection risk.…”