alexa Downhill Skiing: A Putative Model of Hypoxia Preconditioning? | Open Access Journals
ISSN: 2155-9880
Journal of Clinical & Experimental Cardiology
Like us on:
Make the best use of Scientific Research and information from our 700+ peer reviewed, Open Access Journals that operates with the help of 50,000+ Editorial Board Members and esteemed reviewers and 1000+ Scientific associations in Medical, Clinical, Pharmaceutical, Engineering, Technology and Management Fields.
Meet Inspiring Speakers and Experts at our 3000+ Global Conferenceseries Events with over 600+ Conferences, 1200+ Symposiums and 1200+ Workshops on
Medical, Pharma, Engineering, Science, Technology and Business

Downhill Skiing: A Putative Model of Hypoxia Preconditioning?

Martin Burtscher*
Department of Sport Science, Medical Section, University of Innsbruck, Austria
Corresponding Author : Martin Burtscher
Department of Sport Science, Medical Section
University of Innsbruck, Austria
Tel: 4351250745896
E-mail: [email protected]
Received October 20, 2014; Accepted November 24, 2014; Published December 04, 2014
Citation: Burtscher M (2014) Downhill Skiing: A Putative Model of Hypoxia Preconditioning?. J Clin Exp Cardiolog 5:347. doi:10.4172/2155-9880.1000347
Copyright: © 2014 Burtscher M. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Related article at
DownloadPubmed DownloadScholar Google

Visit for more related articles at Journal of Clinical & Experimental Cardiology

Abstract

Sudden cardiac death (SCD) represents the leading non-traumatic death during downhill skiing, the most popular winter sport worldwide. Remarkably, about 50% of all SCDs happened on the first skiing day particularly when the preceding sleeping altitude was low. From these observations it may be inferred that the SCD risk can be modified by short-term adaptation, i.e. hypoxia preconditioning (HP). Downhill skiing at moderate or high altitude may represent a unique model of HP. In fact, analyses of our data on SCDs in male downhill skiers are consistent with an episode of early protection for about 3 hours and a subsequent vulnerable episode during the first skiing day at altitudes at or above 1700 m.

Abstract

Sudden cardiac death (SCD) represents the leading non-traumatic death during downhill skiing, the most popular winter sport worldwide. Remarkably, about 50% of all SCDs happened on the first skiing day particularly when the preceding sleeping altitude was low. From these observations it may be inferred that the SCD risk can be modified by short-term adaptation, i.e. hypoxia preconditioning (HP). Downhill skiing at moderate or high altitude may represent a unique model of HP. In fact, analyses of our data on SCDs in male downhill skiers are consistent with an episode of early protection for about 3 hours and a subsequent vulnerable episode during the first skiing day at altitudes at or above 1700 m.
 
Sudden cardiac death (SCD) represents the leading non-traumatic death during downhill skiing, the most popular winter sport worldwide. More than 90% of all SCDs are attributed to male skiers over 34 years with pre-existing cardiovascular diseases [1]. Remarkably, about 50% of all SCDs happened on the first skiing day particularly when the preceding sleeping altitude was low [2]. From these observations it may be inferred that the SCD risk can be modified by short-term adaptations in terms of preconditioning. Both exercise and hypoxia are capable to induce such adaptations, e.g. including the respiratory, cardiovascular, metabolic and autonomic nervous systems, potentially contributing to subsequent cardio protection [3,4]. Since sleeping at moderate altitude before exercising at altitude reduced the risk of SCD, hypoxia preconditioning (HP) seems to be of particular importance. Preconditioning describes a powerful endogenous mechanism protecting an organ against damage. After single or repeated exposures to a noxious stimulus below the threshold of damage, e.g. hypoxia, the organism develops tolerance to similar or even different stimuli [5]. Hypoxia has been used as a preconditioning stimulus since the 1990ties and has emerged as an easily and safely applicable stimulus preventing several organs including the heart against subsequent injury [6].

The protective effects of HP result from a single exposure or several short episodes (2 to 10 min) of hypoxia. Protection occurs immediately (early protection), lasting for a few hours, or delayed (late protection after a vulnerable phase of about 24 hours), lasting for several days [3,4]. The preventive efficacy of HP has extensively been studied in animals but experimental and clinical data from humans are lacking. However, studies performing remote ischemic preconditioning confirmed the time course of early and late protection, as stated above, against endothelial ischemia-reperfusion injury in humans [7]. Thus, downhill skiing at moderate or high altitude may represent a unique model of HP. Skiers perform repeated downhill runs of a several minutes duration using ski lifts or cable cars to ascend repeatedly from lower to higher altitude. At about 2000 m arterial oxygen saturation values remain relatively high during rest (>90%) but drop below 85% during short physical activities especially on the first day at altitude [8]. If cardio protective HP effects are generated during downhill skiing they should become evident from the time-dependent occurrence of SCDs at altitude. In fact, analyses of our data on SCDs in male downhill skiers are consistent with an episode of early protection for about 3 hours and a subsequent vulnerable episode during the first skiing day at altitudes at or above 1700 m (Figure 1).

*indicates significant between-group differences in SCD frequencies during the first 3 skiing hours vs. those during the hours 4 and 5 (P<0.05). There are no differences between groups regarding age, body mass index, cardiovascular risk factors, regular physical activity, skiing skills, living altitude, daily skiing duration, and day-time of skiing start.

In addition, after 3 hours of skiing several triggers like lactic acidosis, increased serum free fatty acid concentrations, hypoglycaemia, or intra- and extracellular electrolyte derangements may contribute to the increase of the SCD risk. No altitude-dependent differences in SCD frequencies were found from the second to the fifth skiing day. Thus, skiers at risk might actually benefit from HP but should urgently avoid skiing longer than 3 hours on the first day at altitudes above 1700 m. In fact, this clinical setting could represent a real-life model for HP but is clearly limited by the largely varying altitudes of ski areas, the varying individual skiing intensities and exposure times, and the small number of patients as well.
 
References










 

Figures at a glance

Figure
Figure 1
Select your language of interest to view the total content in your interested language
Post your comment

Share This Article

Relevant Topics

Recommended Conferences

Article Usage

  • Total views: 11510
  • [From(publication date):
    November-2014 - Jun 28, 2017]
  • Breakdown by view type
  • HTML page views : 7766
  • PDF downloads :3744
 

Post your comment

captcha   Reload  Can't read the image? click here to refresh

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords