Thursday 24 November 2016

Ski fit series: Altitude effects and cardiovasular fitness

The higher you climb the thinner the air gets.  The thinner the air, the less oxygen available which can affect your energy levels and general well being. Although there are no quick fixes to prevent this, having a good pre-existing level of cardiovascular fitness, as with any sport will help you to exercise for longer.  

At altitude, everyone breathes deeper and faster because of the difference between atmospheric pressure at altitude and sea level.  Exercise increases oxygen requirements, which means your heart rate gets up faster and subsequently you wear out quicker.

At altitude, the amount of oxygen in the air is the same as at sea level (21%).  However, at altitude, the air becomes less dense (thinner) therefore there are fewer oxygen molecules available.  Over time your body will acclimatise to this.
There are both immediate and longer term physiological changes when living at high altitude, so the overall adaptation will depend if you are on holiday for a week or doing a ski season.

One of the main immediate responses is that the body adapts by increasing our breathing rate, both at rest and during exercise.  People often notice that when climbing the stairs in a ski resort, they become much more short of breathe than they would at sea level.

To help preserve oxygen delivery, cardiac output (the volume of blood being pumped by our heart) increases. However, this is only temporary and within a few days our cardiac output will lower (to levels lower than pre-ascent) as other physiological adaptations occur.  As well as a lower cardiac output, longer term changes also include an increase in number of red blood cells and changes in muscle metabolism.

According to Wikipedia, altitude training and the effects of altitude on performance became a hot topic after the 1968 Olympic Games in Mexico city which is at an elevation of 2,240 metres (7349 ft).  It was noted that endurance events saw a significant number of below record finishes, whilst anaerobic, sprint events excelled.  Still today, the physiological effects of altitude and its role in training high for performance enhancement are an exciting on-going topic of research.

Points to remember:
  • In general, the higher the altitude, the longer it takes to adapt.
  • Although most ski resorts are said to be at moderate altitude, rather than high altitude, acclimation is just as important and it is not uncommon to feel mild to moderate effects during this period. 
  • Unfortunately, there is no link between your pre-existing fitness levels and how quickly you acclimatise, however the fitter you are theoretically the longer you will be able to ski for. 
  • The better your cardiovascular fitness, the better prepared you will be to cope with physical demands of sport and exercise at altitude. 
  • Good cardiovascular fitness will improve your stamina. 
  • The cold also affects yours cardiovascular system.
So with this in mind, it is definitely worth improving your cardiovascular fitness prior to your skiing holiday.  The aim of cardiovascular exercise is to get your heart and lungs working hard for extended periods.

Recommendations pre-skiing:
  • Start to increase (or introduce) cardiovascular training at least 6 weeks prior to your ski trip or ski season
  • Aim for 2 - 4 cardiovascular sessions a week.  These sessions should last at least 20 - 40 minutes in duration and ideally you should be working at around 50-60 % of your maximum heart rate.
  • Ensure your training has variety and is progressive; each week try and up your pace, vary your workouts, introduce interval training and vary the length of the workouts that you are doing e.g. mix and match shorter 20 minute sessions with long bike rides and hill walks.
  • Outdoor examples of cardiovascular exercise include running, cycling and hill walking.
  • Cycling is very popular with world cup skiers as well as ski instructors.  Many ski instructors have a turbo trainer in their apartments to help increase cardiovascular fitness to compliment / enhance their skiing. 
  • In the gym you can use the treadmill, bike or cross-trainer to work on your cardiovascular system, as well as introducing circuits and aerobic type classes. 
Other Considerations:

To further help you acclimatise and to help to enhance the functioning of cardiovascular system, take into account the following when you are at altitude.
  • Gradually build up your time on the hill
  • Consider your diet
    • An initial decline in appetite is not uncommon so think about what you are eating. A high carbohydrate, low salt diet allows for better adaptation.  Choose slow release carbohydrates rather than refined sugary snacks and meals which help to keep your blood sugars steady e.g. whole grains, legumes, fruit and vegetables
    • If you are at altitude for long periods, consider that your body will be making more red blood cells.  This may mean a higher demand for iron so ensure you include iron rich foods in your diet e.g. spinach, liver, mussels, oysters, cooked chicken and beef and sardines. 
  • Stay well hydrated.  Mountain air is extremely dry, therefore you lose a lot of water.  You need to drink a lot more than you think in the mountains. 
  • It is best to limit alcohol consumption during the acclimatisation period as it increases your risk of dehydration and can increase feelings of loss of appetite and fatigue. 
  • If you have a pre-existing cardiovascular disorder, it is worth talking to your Doctor before ascending to a high altitude.  
  • If you suffer from headaches, malaise and decreased appetite at altitude, your body needs more time to adapt so don't over do it, especially when you first start skiing or boarding.  
References:

Cardiovascular adaptation to exercise at high altitude.
Exerc Sport Sci Rev. 1986;14:269-302. Grover RFWeil JVReeves JT.

Disclaimer:

The purpose of this blog, is to provide general information and educational material relating to physiotherapy and injury management. Bonne Santé physiotherapy has made every effort to provide you with correct, up-to-date information. In using this blog, you agree that information is provided 'as is, as available', without warranty and that you use the information at your own risk. We recommend that you seek advise from a fitness or healthcare professional if you require further advice relating to exercise or medical issues.

LSA
       Bonne Santé          info@bonnesantephysio.com         0033 (0) 4 79 06 07 27

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Sunday 6 November 2016

Ski fit series: Analysing the demands

'How should I get fit to ski?' is a difficult question to answer.  Everyone of you will have individual needs depending on your current levels of strength, endurance and fitness. Factors such as previous injuries, current lifestyle and hobbies, muscle imbalances, level and type of skiing that you will be doing will also need to be taken into account when planning your ski fit program.

                              There is no 'one size fits all'.

However, one thing for certain is that ski fitness is a big deciding factor between having an enjoyable ski trip or a painful one.  Being fit to ski can make a difference as to whether you can progress your skills on the slopes or whether you have a high injury risk.  Poor fitness leads to increased fatigue which is cited as probably the biggest reason for injuries occurring on the slopes.

You wouldn't attempt to run a marathon without training and whilst you may take regular breaks on the slopes, often you will be spending 4 - 6 hours a day on your skis and asking huge demands from your body.  A large proportion of the injuries we see have occurred in people who have rushed into skiing and boarding without being fully prepared.  An audit we carried out a few years ago suggested that less than 10 % of people seeking treatment for injuries had worked on their leg strength prior to their skiing holidays.

One of our roles as physiotherapist is education and injury prevention. We regularly lecture to trainee ski instructors to help them train effectively and to help them become better informed teachers. However, when we ask for a show of hands as to who has prepared physically, again less than 10% have done any ski fit training.

It doesn't matter if you are a regular runner, gym goer or cross trainer.  It doesn't matter if you are a professional couch potato for 51 weeks of the year then aim to ski the one other week or whether you are a sedentary office worker or a professional athlete.  Ski preparation, that starts 6 - 8 weeks before you hit the slopes is the best way to enhance your enjoyment, improve your performance and decrease injury risk on the slopes.  Of course, you can usually get fixed when you are broken but how about avoiding getting to that point in the first place!

Fit to Ski?
                  Injury prevention - perform better for longer  

Overuse injuries are generally caused by overloading, in other words asking to much from unprepared muscles.  So many of these injuries could be avoided. Getting 'fit to ski' involves functional training. This means tailoring your training program to the demands of your sport.

Lets look at some of the main components you need for skiing.  These include (but are not limited to):
  • Strength and endurance
  • Balance and proprioception
  • Flexibility and mobility
  • Plyometric strength and agility
Of course, the type of skiing you do will also dictate your training needs.  For example, if you are a recreational skier, you will need to steadily train all of the above.  However, if you are a bumps skier then you will need to increase your focus on lower back, hip and knee flexibility along with a large emphasis on plyometric strength.  If you ski off piste or go ski touring, you will need good endurance, balance and cardiovascular endurance.  So you see, giving out a generic ski fit program is not so simple as there are too many factors to take into account.  However, we will be giving you ideas for training over the next few weeks that you can incorporate into an overall training regime.   

As you introduce the concepts of ski fitness, make sure that the different components are introduced gradually.  Sudden increases in training intensity, load and frequency can lead to injury themselves, therefore we recommend seeking the advice of a professional.  A great way to ensure you are introducing a variety of exercises in a safe manner is to consult a personal trainer or join a ski fit class. There are ways of preventing injuries such as a structured warm up, management of training load, pacing and correct use of equipment.  However, over the coming weeks in our ski fit series we will be introducing ideas for exercises. 


When you are about to get started ask yourself a few questions:
  • How much exercise do I currently do / what are my current fitness levels?
  • How much skiing will I be doing - am I preparing for a weeks holiday or a whole season?
  • What is my current level of skiing? 
  • What type of skiing will I be doing? 
  • What hobbies and activites do I currently do which may influence my skiing eg if you spend a lot of time sitting you are likely to have tight and weak hip flexors (the muscles in the front of your hip and thigh which flex your hip and work a lot when you ski).  If so, your training plan may need to address this, 
Follow our ski fit series over the next few weeks to learn how to introduce various components of ski fitness into your training program.  If you are already training in Tignes, book in for a biomechanical assessment with us to help identify your training needs.
Disclaimer:

The purpose of this blog, is to provide general information and educational material relating to physiotherapy and injury management. Bonne Santé physiotherapy has made every effort to provide you with correct, up-to-date information. In using this blog, you agree that information is provided 'as is, as available', without warranty and that you use the information at your own risk. We recommend that you seek advise from a fitness or healthcare professional if you require further advice relating to exercise or medical issues.


LSA
       Bonne Santé          info@bonnesantephysio.com         0033 (0) 4 79 06 07 27

Please like us on Facebook to stay up to date with news and developments: Bonne Sante Physiotherapy 
Follow us on instagram: Bonne_Sante_Physiotherapy

Follow us on twitter: @valdiserephysio