It takes more than a mask – Part 2: Altitude tents
As boxers and coaches become more familiar with altitude training, we review the benefits and preferred methods to improve a boxers fitness.
Following Gareth Turner’s introductory article, Sport physiologist Alan Ruddock further explores the altitude training hype.
As Gareth presented in our first article on this series; on top of a mountain barometric pressure is reduced but the fraction of inspired oxygen remains the same as at sea level. It’s this lower pressure that ultimately makes exercising harder at altitude.
As you descend from altitude the air pressure increases, until you hit what we call “sea-level”. At this point the altitude is considered to be normal and isn’t a factor that comprises intensity of exercise.
So if the pressure isn’t different how do altitude systems work at sea level?
Altitude tents, like the one we have at Centre for Sport and Exercise Science, Sheffield Hallam University, mimic altitude by changing the oxygen content of the air inside the chamber.
Typically, a generator pulls in atmospheric air and the system adds nitrogen to it which reduces oxygen content. This air is then pumped via a tube into the tent and athletes breathe in this air.
The physiological result caused by this manipulation of air is similar to that observed at an equivalent altitude.
As Gareth pointed out in his article there are three main types of altitude training. Out of these three types there’s really only one method accessible for the vast majority of boxers to undertake at sea level and that’s “Live-Low-Train High” (LLTH).
Using this method a boxer would train in an altitude tent but live at sea level. This sounds like a good idea, but the benefits from using this method are unclear and consistently training at altitude might actually be detrimental to performance.
The Science
An interesting piece of research was published by Gareth and his team at the University of Brighton. In the study they asked athletes to perform repeated sprints of 5 s with recovery periods of 115 s over 40 min at a simulated altitude of 1600 m.
They found that simulated altitude impaired the athlete’s ability to produce force during the sprints and concluded that athletes were at a disadvantage when performing intermittent sprints at moderate altitude.
We can interpret these findings in three ways;
- Firstly, as concluded it’s harder to produce repeated high force efforts at altitude.
- Secondly, a reduced ability to produce force limits the mechanical benefits of sprinting.
- Finally, a decreased ability to produce force lowers mechanical strain on the muscles, joints and ligaments.
Interestingly, heart rate was higher and oxygen saturation was lower at this altitude during exercise. This means that despite a lower external intensity (speed/mechanical power output), internal intensity remained high. This is the opposite of what you’d expect to see at sea-level. Essentially, if you’re unfatigued and run slower, your internal intensity (typically indicated by heart rate or oxygen uptake) decreases.
The Boxing Science Way
This finding of a lower external intensity and higher internal intensity is the reason underpinning our use of altitude training.
When our boxers have been lifting heavy and sprinting hard, after 3 weeks or so we need to let them recover and help the body adapt to the training stimuli. To do this we schedule a recovery week.
When we didn’t have use of the altitude tent, our recovery week involved lower intensity and non-specific exercise using low impact pieces of equipment (such as a cycle or x-trainer). This type of programming decreased both external and internal intensity thus training load.
However, with our altitude tent positioned over the curve treadmill, we’re able to continue with boxing specific running training. The external load (speed) is decreased but crucially internal demand remains at the intensity we require because of the altitude.
Recovery
So we schedule mechanical de-load weeks to decrease the strain on muscles and joints whilst maintaining sufficient internal demand on the cardiovascular system to support its progressive adaptation.
What’s important to recognise is that we do not use the altitude tent as a means of LLTH method – ie. It’s not used in the traditional way altitude training is used to increase red blood cells.
Although on the face on it consistent altitude training might look tempting, our work in the altitude tent is not our primary means of conditioning, quite simply because it decreases the ability of our boxers to produce force.
We want our boxers to be as forceful as possible and to do this we have to train to produce high forces and then repeat them.
Like all our training, we use the altitude tent in a strategic, considered and systematic manner; it’s not thrown into a programme at random points for the sake of it. If you have the opportunity to use an altitude tent, you should seek qualified expert advice before doing so to ensure that it’s appropriate and safe for your needs.
This is what our recovery weeks now look like.
In summary:
- Training in an altitude tent is not the same as training at altitude
- We use altitude training as a mechanical de-load tool at strategic time points in a boxers training programme
- If you have the opportunity to use an altitude tent seek appropriately qualified and expert advice – we are more than happy to help.
If you would like any additional information on how you can use our altitude training system get in touch with Danny at D.Wilson@shu.ac.uk