Hello,

Unfortunately, there is no predictive test which would enable you to select who should use altitude training and who shouldn't or predict the outcome of the training camp.

I would recommend to run a ventilatory response test to get at list an idea of how well you can expect the athletes to respond to the altitude stimulus. Again, it is more an indicator than an exact figure.

In any case, I would recommend to be gentle (both altitude and training) over the first few days especially if you plan to go quite high, eg. >3,000m.

Good luck!!

Hello Vasanth,

I agree with Julien in that no predictive tests are available. However,  you could use look at the appearance of signs of acute mountain sickness (e.g. Lake Louise AMS questionnaire) to detect abnormal response to hypoxic exposure. As a rule of thumb, subjects attaining scores >5 should be closely monitored and altitude should be reached on slow pace. Subjects >10 should start from a much lower altitude and progress slowly.

I also agree completely with Julien's last advice.

All the best! 

Dear Julien and Ferran, thanking you much for the update. how about using pulse oximeter? any good are they for this? Thanks much gentlemen.

Hi Vasanth, 

I agree with the Julien and Ferran's points. Re. a pulse oximeter you should be monitoring the athletes and staff as a matter of course a low reading initial reading is not predictive of problems. However, your question is a little vagueerhaps a little more detail on what you intend to do might elicit a greater response from the ResearchGate community. 

Dear Stephen, Thanks much for the suggestion. I am planning to incorporate a hypoxic chamber at my sports performance premises. I want guidance in setting up a protocol for assessment and exercise prescription and the application of Pulse oximeter in finding the hypoxic levels of the individuals during the workout. Like a cooper test (pre set values) in testing is there any particular protocols available to be used in exercise testing? in addition, age related values or percentage that a person can achieve (hypoxic levels)? 

Hellou Vasanth, using pulse oximeter is must. By intermittent hypoxia (5 min hypoxia and 5 min normoxia in total of 1,5 hour) I usually go through this protocol: First two weeks I would not get athletes to drop below saturation of 90% Next 2 weeks gradually increase “altitude” (decrease oxygen in inhaled air) 90-80%. Do not drop below 88% anytime. When exercise with hypoxia (normobartic) f.e. running o treadmill (92-95% is optimal). Otherwise the power (speed) is too low. By exposure to hypoxia during rest for more hours, 90% and lower I would not advise for unsuccessful regeneration. Pulse oximeter shows you different reactions of athletes and thus to differ altitude settings.

HI Vasanth

I assume that your system is a normobaric hypoxic tent. As indicated before, there are wide individual differences in response to acute hypoxa exposure. It was pointed out by Julien and Ferran: you must closely monitorize your subjects along all the exposure procedure, prefereably controling not only arterial oxygen saturation and heart rate (pulsioximeter) but also ventilatory drive (respiratory frequency and minute volume or tidal volume) at least in the first exposure events. For an expert eye, the evlution of these parameters allow to recognize normal or abnormal responses to acute hypoxia.

I never should recommend ultra-short intermittent hypoxia exposure in a pattern as indicated by Viktor. Why use a model similar to obstructive sleep apnea (OSA) that all we know elicits pathological readljustments such as hypertension?

Another interesting point is that more and more researchers increasingly accept nowadays that the stimulus induced by normobaric and hypobaric hypoxia are not equivalents. See this articles

http://www.ncbi.nlm.nih.gov/pubmed/23524575

http://www.ncbi.nlm.nih.gov/pubmed/22653279

http://www.ncbi.nlm.nih.gov/pubmed/22895381

http://www.apunts.org/en/pdf/90328576/S300/

Ahhhh Ginés, you're starting a debate close to my heart as I argued in point-counterpoint for J Appl Physiol a little while ago that the adaptations are PO2 driven and that as a consequence normobaric hypoxia is very similar to hypobaric hypoxia. But that a separate question, I guess...

One thing we do agree on though, is the question regarding the efficacy if not inocuity of using short bouts of altitude.

I would personally also add a word of caution regarding generic SaO2 targets. It is very much individual dependent which means that I may need to reach only 2000m to desaturate down to 90% while somebody else will need to go up to 2500m or even 3000m. This, especially when combined with exercise, are two completely different stimuli.

I think that if you want to go down that route, you would need to know your athletes and how they respond to hypoxia. That was the original question, to which we didn't have a clear answer...

Hi Vasanth,

Of course standard medical screening is needed prior to testing and training in hypoxia in order to exclude pathologies contra-indicated for maximal exercise in hypoxia.

Regarding to screening aiming to identify responders vs non-responders to intermittent hypoxic training (IHT), I don’t think good data exists. However, some studies tried to identify markers predicting the response to live high-train low (or high). Among others, initial Hbmass, iron status, EPO response whithin the early phase of the training camp (~30 h), energy balance, heart rate variability & AMS-score (as a marker for the ability to cope with the given stress), and injury/illness/inflammation have been reported to influence the response in Hbmass. Yet unfortunately apriori differentiating responders from non-responders is still not possible. Moreover, one does not seem to respond consistently to two altitude training camps from year to year, so genetics do not seem to play a major role either.

But your question relates to IHT, not LHTL or LHTH (or a combination of those). I think an important question to ask is (1) what are you aiming for with hypoxic supplementation to training and (2) what training protocol would be ideal to realize this goal (and do we gain benefit by performing the training in hypoxia)?

Based on single leg studies from the 1990's (Terrados, Melissa, Green), and later by the work of Hoppeler's group, high-intensity endurance-based training protocols seemed to elicit greater muscular adaptations when performed in hypoxia compared to normoxia. Regarding to adaptations in aerobic metabolism that is. Yet these studies did not consistently result in performance adaptations! More recently, attention has shifted towards training based on short all-out efforts. Although wingate-based training does not seem to benefit greatly from hypoxic supplementation, repeated sprint training (repeated 10-s sprint interspersed by short recovery of ~20 s) does. Make sure you read the RSH-papers from Millet's group!

As for target SpO2's during training, I find it difficult to answer. Of course there is the trade off between greater desaturation (hypoxic stress) and loss in power output to keep in mind. But whitin reasonable values of SpO2, this seems to be a rather speculative debate to me. For instance, I would first like to know to what extent SpO2 correlates with myocellular oxygen availibility during (sprint) exercise. Furthermore, I wonder whether a greater intramyocellular O2 deficit also mediates greater HIF accumulation and hence target gene transcription. Or is this more a ‘everything or nothing’ response? Where lies the myocellular O2 threshold for HIF stabilization? Anyhow, I am not aware of training studies reporting a better or worse response with a certain altitude whithin the range of ~ 2500 - 4500 m, but I would be more than happy to hear otherwise.

All the best!

Stefan

References regarding response to LHTL or LHTH: Robach SJMSS 2012, Chapman JAP 1998, McLean BJSM 2013, Stray Gunderson MSSE 1992 (abstract), Wachsmuth EJAP 2013, Jelkmann JICR 1998, Hamlin WASET 2011 (Apologies for unofficial abbreviations, just ask if not clear to you).