Relative match intensities at high altitude in highly-trained young soccer players (isa3600)

qantas-joeys-held-to-scoreless-draw-in-bolivia_00048620-leadimageMartin Buchheit, Kristal Hammond, Pitre C. Bourdon, Ben M. Simpson, Laura A. Garvican-Lewis, Walter F. Schmidt, Christopher J. Gore and Robert J. Aughey. Relative match intensities at high altitude in highly-trained young soccer players (isa3600). Journal of Sports Science and Medicine, In press.

Figure 1Full text here


To compare relative match intensities of sea-level versus high-altitude native soccer players during a 2-week camp at 3600 m, data from 7 sea-level (Australian U17 National team, AUS) and 6 high-altitude (a Bolivian U18 team, BOL) native soccer players were analysed. Two matches were played at sea-level and three at 3600 m on Days 1, 6 and 13. The Yo-Yo Intermittent recovery test (vYo-YoIR1) was performed at sea-level, and on Days 3 and 10. Match activity profiles were measured via 10-Hz GPS. Distance covered >14.4 km.h-1 (D>14.4 km.h-1) and >80% of vYo-YoIR1 (D>80%vYo-YoIR1) were examined.

Upon arrival at altitude, there was a greater decrement in vYo-YoIR1 (Cohen’s d +1.0, 90%CL ± 0.8) and D>14.4 km.h-1 (+0.5 ± 0.8) in AUS. D>14.4 km.h-1 was similarly reduced relative to vYo-YoIR1 in both groups, so that D>80%vYo-YoIR1 remained similarly unchanged (-0.1 ± 0.8). Throughout the altitude sojourn, vYo-YoIR1 and D>14.4 km.h-1 increased in parallel in AUS, so that D>80%vYo-YoIR1 remained stable in AUS (+6.0%/match, 90%CL ± 6.7); conversely D>80%vYo-YoIR1 decreased largely in BOL (-12.2%/match ± 6.2).

In sea-level natives competing at high-altitude, changes in match running performance likely follow those in high-intensity running performance. Bolivian data confirm that increases in ‘fitness’ do not necessarily translate into greater match running performance, but rather in reduced relative exercise intensity.

Key words: association football; hypoxia; match running performance


Yin and yang, or peas in a pod? Individual-sport versus team-sport athletes and altitude training

Robert J Aughey, Martin Buchheit, Laura A Garvican-Lewis, Gregory D Roach, Charli  Sargent, François Billaut, Matthew C Varley, Pitre C Bourdon, Christopher J Gore

Screenshot - 19_11_2013 , 4_12_55 PM


The question of whether altitude training can enhance subsequent sea-level performance has been well investigated over many decades. However, research on this topic has focused on athletes from individual or endurance sports, with scant number of studies on team-sport athletes. Questions that need to be answered include whether this type of training may enhance team-sport athlete performance, when success in team-sport is often more based on technical and tactical ability rather than physical capacity per se.

This review will contrast and compare athletes from two sports representative of endurance (cycling) and team-sports (soccer). Specifically, we draw on the respective competition schedules, physiological capacities, activity profiles and energetics of each sport to compare the similarities between athletes from these sports and discuss the relative merits of altitude training for these athletes. The application of conventional live-high, train-high; live-high, train-low; and intermittent hypoxic training for team-sport athletes in the context of the above will be presented. When the above points are considered, we will conclude that dependent on resources and training objectives, altitude training can be seen as an attractive proposition to enhance the physical performance of team-sport athletes without the need for an obvious increase in training load.

Adding heat to the live-high train-low altitude model: a practical insight from professional football

aus-rule-football-2Finally! After 7 rejections, ‘one of the most rejected paper’ was accepted this morning in the Altitude for team sports BrJSM issue (following Aspetar conference in March 2013). I already see some readers saying “hum… a special issue? Aspetar is actually paying for it? This is why the paper was accepted!  – can’t be a good one with its rejection history!” Fair enough. But to be honest, I really don’t care why or where this paper is published today. The study ran with the Carlton FC (AFL) boys in November 2011 in Doha is probably one the very best study I ever had the chance to be involved in (competing with the 2012 Football project in La Paz for the first place). Results have to be published, because they matter to us (physiologists, sport scientists or strength & conditioning coaches). I would like to see someone working in elite team sports not interested in the results… any one?

The scientific publication process is a game; Sometimes you lose, Sometimes you win. The story of this study is worth taking a few minutes of your time, since it perfectly illustrates the problem that we have to face at each submission.

1. We are interested in practical studies, with practical results in elite players. I can’t be bothered conducting an altitude training study in recreational players, since these latter might definitively not be lucky enough to be given the opportunity (time and money) to do so. The problem is that with elite players in a real life scenario (i.e., pre-season camp), you have to do some concessions, which might partly affect the study design (e.g., group allocation, nature of the performance/physiological measures). However, the practical outcomes undoubtedly balance some of the possible methodological flaws/limitations. In the present study, our aim was ONLY to compare the MAGNITUDE of the effect on performance and some physiological variables of 2 different training approaches (heat only, or heat + altitude), that could be practically implemented in elite players. We definitively missed a control group (no heat, no simulated altitude) to assess the exact effect of heat per se. Fair enough. But from a practical point of view, this is not that of a problem. We just wanted to know whether adding the hypoxic stimuli is worthwhile, compared with heat only. Results show that the additional altitude training effect is very limited, which clearly answer our question – and again, I am sure that most practitioners would be happy with this. When compared with historical data from the previous years, we also documented a greater and faster improvement in performance, suggesting that the present intervention(s) were pretty awesome (likely because of the heat, but we can’t say it with absolute confidence…:)). Again, from a practical point of view, this is a cool result and this should be enough to deserve publication!?

–> Problem: Reviewers and editors want perfectly controlled study designs, and don’t care about the practical applications. They want you to answer physiological questions first. They don’t understand how load can be controlled outside the lab. They have never heard about session RPE, or GPS technology (actually this is the lady voice that asks you to do a u-turn when you missed the exit in your car). In short, the ignorance of reviewers and editors lead them to miss the fact that our field studies are actually much more controlled that they though. This attitude lead some editors to reject the paper at their level (didn’t want to waste reviewers’ time – MSS, EJAP – and even better, in Scan JMSS, S. Harridge, the editor in chief managed to disregard a quite positive review from a well-known AIS physiologist – pretending he didn’t get the review to justify his rejection. Yes, this is the reality!! This same editor had already rejected another paper because cold water immersion was not blinded in this study… !?). Just to show you how treated our papers are sometimes.

2. We have to use appropriate statistics, i.e., which highlight the magnitude of the training effects.

–> Problem: Reviewers in the altitude business spent too much time behind their desk, and simply want P values. With the 7 rejections and sometimes 3 reviews per submission, I had the chance to gather a few nuggets, as the legendary: “The study has some potential, but could you please run some stats?” What can we do? Will Hopkins wrote on another occasion: “I can’t be bothered addressing this kind of criticism. If you believe in God, no amount of evidence against His existence will disabuse you of your belief. Similarly, if you believe in null-hypothesis testing, the evidence for a better method of making inferences about true effects means nothing to you. In any case, has this person read the evidence? I doubt it.”

If I (we) had to do it again, I (we) would do exactly the same.

2011-10-20 14.45.16 2011-10-19 17.13.58

Buchheit, M., Racinais, S., Bilsborough, J., Hocking, J., Mendez-Villanueva, A., Bourdon, P.C., Voss, S., Livingston, S., Christian R.,  Périard J., Cordy, J., and Coutts, A.J. Adding heat to the live-high train-low altitude model: a practical insight from professional football. BJSM In press.

What is known on this subject
•    Hypoxic exposure (live-high, train-low model) can increase hemoglobin mass, especially in athletes with low baseline levels such as team sport players.
•    Short term heat acclimatization can increase plasma volume team sport players.
•    Combined, increased hemoglobin mass and plasma volume improve total blood volume and convective O2 delivery, which can, under some circumstances, improve high-intensity exercise performance.

What is this study adds
•    Pre-season outdoor football training in hot ambient conditions induces (at least) partial heat acclimatization in professional Australian Rules Football players, and is associated with very large improvements in high-intensity running performance.
•    The substantial increases in hemoglobin mass and blood volume observed immediately after a ‘live high-train low in the heat’ camp can last at least one month.
•    Compared with training in the heat only, an additional hypoxic stimulus during sleep and some training sessions has no high-intensity running performance benefits immediately after the camp. The possible greater delayed effects of the hypoxic exposure, if any, are only small in magnitude.


Objectives. To examine with a parallel group study design the performance and physiological responses to a 14-day off-season ‘live high-train low in the heat’ training camp in elite Football players.
Methods. Seventeen professional Australian Rules Football players participated in outdoor football-specific skills (32±1˚C, 11.5h) and indoor strength (23±1˚C, 9.3h) sessions, and slept (12 nights) and cycled indoors (4.3h) in either normal air (NORM, n=8) or normobaric hypoxia (14±1 h/day, FiO2 15.2-14.3%, corresponding to a simulated altitude of 2500-3000 m, HYP, n=9). They completed the Yo-Yo Intermittent Recovery level 2 (Yo-YoIR2) in temperate conditions (23±1˚C, normal air) Pre and Post. Plasma volume (PV) and hemoglobin mass (Hbmass) were measured at similar times and 4 weeks post camp (4WPost). Sweat sodium concentration ([Na+]sweat) was measured Pre and Post camp during a heat-response test (44ºC).
Results. Both groups showed very large improvements in Yo-YoIR2 at Post (+44%; 90%CL 38,50), with no between-group differences in the changes (-1%; -9,9). Post camp, large changes in PV (+5.6%; -1.8,5.6) and [Na+]sweat (-29%; -37,-19) were observed in both groups, while Hbmass only moderately increased in HYP (+2.6%; 0.5,4.5). At 4WPost, there was a likely slightly greater increase in Hbmass (+4.6%; 0.0,9.3) and PV (+6%; -5,18, unclear) in HYP than in NORM. Conclusions. The combination of heat and hypoxic exposure during sleep/training might offer a promising ‘conditioning cocktail’ in team sports.

Wellness, fatigue and physical performance acclimatisation to a 2-week soccer camp at 3600 m

2012-08-19 10.35.31 2012-08-16 12.18.56 2012-08-24 09.12.11

Buchheit M, Ben M. Simpson, Laura A. Garvican-Lewis, Kristal Hammond, Marlen Kley, Walter F. Schmidt, Robert J. Aughey, Rudy Soria, Charli Sargent, Gregory D. Roach, Jesus C. Jimenez Claros, Nadine Wachsmuth, Christopher J. Gore and Pitre C. Bourdon. Wellness, fatigue and physical performance acclimatisation to a 2-week soccer camp at 3600 m (ISA3600). British J Sports Med, 2014, In press.

What is known on this subject

 The decreased oxygen availability at high altitude impairs aerobic exercise capacity; conversely, single sprint performance is acutely improved.

  • Psychometric and physiological measures, such as questionnaires or heart rate (HR) responses, can be used as indicators of acclimatisation to altitude.
  • At least 2 weeks of acclimatisation at the altitude of competition is generally recommended before playing matches, but information on team sports is lacking.

What this study adds

 Two weeks of acclimatisation at high-altitude is not long enough for native sea-level players to fully recover their high-intensity running performance, despite resting measures of HR, HR variability and wellness having returned to normal.

  • A two-week altitude training camp may impair sprint performance, probably as a result of the inability to maintain an appropriate neuromuscular load during training and matches.
  • The HR response to a submaximal running test can be used to estimate changes in high-intensity performance at altitude in native sea-level players.


Objectives. To examine the time-course of wellness, fatigue and performance during an altitude training camp (La Paz, 3600m) in two groups of either sea-level (Australian) or altitude (Bolivian) native young soccer players. Methods. Wellness and fatigue were assessed using questionnaires and resting heart rate (HR) and HR variability. Physical performance was assessed using HR responses to a submaximal run, a Yo-Yo Intermittent recovery test level 1 (Yo-YoIR1) and a 20-m sprint. Most measures were performed daily, with the exception of Yo-YoIR1 and 20-m sprints, which were performed near sea-level and on days 3 and 10 at altitude.

Results. Compared with near sea-level, Australians had moderate-to-large impairments in wellness and Yo-YoIR1 relative to the Bolivians upon arrival at altitude. The acclimatisation of most measures to altitude was substantially slower in Australians than Bolivians, with only Bolivians reaching near sea-level baseline high-intensity running by the end of the camp. Both teams had moderately impaired 20-m sprinting at the end of the camp. Exercise HR had large associations (r > 0.5-0.7) with changes in Yo-YoIR1 in both groups.

Conclusion. Despite partial physiological and perceptual acclimatisation, 2 weeks is insufficient for restoration of physical performance in young sea-level native soccer players. Because of the possible decrement in 20-m sprint time, a greater emphasis on speed training may be required during and after altitude training. The specific time-course of restoration for each variable suggests that they measure different aspects of acclimatisation to 3600m; they should therefore be used in combination to assess adaptation to altitude.

Predicting sickness during a 2-week soccer camp at 3600 m

2012-08-23 11.37.21

Martin Buchheit, Ben M. Simpson, Walter F. Schmidt, Robert J. Aughey, Rudy Soria, Robert A. Hunt, Laura A. Garvican-Lewis, David B. Pyne, Christopher J. Gore and Pitre C. Bourdon. Predicting sickness during a 2-week soccer camp at 3600 m (ISA3600). British J Sports Med 2014, In press.

What is known on this subject

  • Living and training at high-altitude presents a physiological challenge for native sea-level athletes, with depressed immune function, altered autonomic function, acute mountain sickness and sleep disturbance often reported.
  • Psychometric and physiological measures, such as questionnaires or resting HR, are used as indicators of general acclimatisation and tolerance to altitude.

What this study adds

  • A >4% increased HR during submaximal exercise, in response to a moderate increase in perceived training load the day before, may be predictive of sickness the following day.
  • All other variables examined including resting HR, HR variability or psychometric questionnaires don’t show consistent changes before sickness


Objectives. To examine the time-course of changes in wellness and health status markers before and after episodes of sickness in young soccer players during a high-altitude training camp (La Paz, 3600m). Methods. Wellness and fatigue were assessed daily upon awakening using specifically-designed questionnaires and resting measures of heart rate (HR) and HR variability. The rating of perceived exertion and HR responses to a submaximal run (9 km·h-1)were also collected during each training session. Players who missed the morning screening for at least two consecutive days were considered as sick. Results. Four players met the inclusion criteria. With the exception of submaximal exercise HR, which showed an almost certain and large increase before the day of sickness (+4%; 90% confidence limits 3,6), there was no clear change in any of the other psychometric or physiological variables. There was a very likely moderate increase (+79%, 22,64) in self-reported training load the day before the HR increase in sick players (4 of the 4 players, 100%). In contrast, training load was likely and slightly decreased (-24%, -78,-11) in players who also showed an increased HR but remained healthy. Conclusion. A >4% increased HR during submaximal exercise in response to a moderate increase in perceived training load the previous day may be an indicator of sickness the next day. All other variables, i.e., resting HR, HR variability and psychometric questionnaires may be less powerful at predicting sickness.

High-intensity Hypoxic Intervals


J Strength Cond Res. 2012 Jan;26(1):94-105. doi: 10.1519/JSC.0b013e3182184fcb.

Physiological strain associated with high-intensity hypoxic intervals in highly trained young runners.


Sport Science Department, ASPIRE Academy for Sports Excellence, Doha, Qatar.


To examine the physiological strain associated with hypoxic high intensity interval training (HHIT), 8 highly trained young runners (age, 18.6 ± 5.3 years) randomly performed, 5 × 3-minute intervals in either normoxic (N, 90% of the velocity associated with VO(2max), vVO(2max)) or hypoxic (H, simulated 2,400-m altitude, 84% of νVO(2max)) conditions. Cardiorespiratory (ventilation [V(E)], oxygen consumption [V(O2)], heart rate [HR], oxygen saturation [SpO(2)]), rating of central perceived exertion (RPE(C)) responses, changes in neutrophils, erythropoietin (EPO), blood lactate ([La]) and, bicarbonate ([HCO(-)(3)]), vagal-related indices of HR variability (natural logarithm of the square root of the mean of the sum of the squares of differences [Ln rMSSD]) and maximal sprint and jump performances were compared after each session. Compared with N, H was associated with similar V(E) (Cohen’s d ± 90% confidence limits, 0.0 ± 0.4, with % chances of higher/similar/lower values of 15/61/24) but at least lower VO(2) (-0.8 ± 0.4, 0/0/100), HR (-0.4 ± 0.4, 1/21/78), and SpO(2) (-1.8 ± 0.4, 0/0/100). Rating of perceived exertion was very likely higher (+0.5 ± 0.4, 92/8/0). Changes in [HCO(3)] (-0.6 ± 0.8, 5/13/83), [La] (+0.2 ± 0.4, 52/42/5), and EPO (+0.2 ± 0.4, 55/40/5) were at least possibly greater after H compared with those after N, whereas changes in neutrophils were likely lower (-0.5 ± 0.7, 4/15/81). Changes in 20-m sprint time (+0.20 ± 0.23, 49/50/1) were possibly lower after H. There was no clear difference in the changes in Ln rMSSD (+0.2 ± 1.7, 48/18/34) and jump (+0.3 ± 0.9, 60/25/15). In conclusion, although perceived as harder, HHIT is not associated with an exaggerated physiological stress in highly trained young athletes. The present results also confirm that HHIT may not be optimal for training both the cardiorespiratory and neuromuscular determinants of running performance in this population.