The paper just published in Frontiers in Physiology outlines the story of my ‘relationship’ with HRV. A bit like a rollercoaster, but with a happy ending!
I started to get interested in HRV as a training monitoring tool in 2001, when I came across the A. Hautala paper showing the HRV recovery time course following a 75-km cross-country skiing race – that was a revelation. I then started a PhD in France the same year, but actually found more limitations than applications if the field, which left me definitely disappointed. Fair enough, these efforts were nevertheless worthwhile since they allowed me to better understand the bases of the ‘HRV tool’, and I managed to do some progress with respect to the optimal ways for data collection and analysis. This was then followed by a first series of applied projects, more centered on acute interventions designed to better understand the mechanisms underlying parasympathetic reactivation post effort (Hani Al Haddad, PhD #2, our first child with HRV). Later, in parallel to the applied work that I conducted on my own and/or through different collaborations, and with my mates in Aspire in Qatar, I have been lucky enough to be involved in the design/supervision of 2 very applied PhDs (Jamie Stanley, PhD #3 in Australia and Dan Plews PhD #4 in New Zealand, the twins of the 2nd delivery). While most of these latter field studies were not the easiest to publish (reflecting again the issues of the publication process, please see other posts), they sealed the methodology to properly monitor athletes, both on a short- and long-term basis. Some of the key take home messages, which are still largely ignored by practitioners, were that HRV measures can’t be used in isolation and that a proper statistical methodology needs to be used – in practice people still collect data at random intervals and try to provide training recommendations based on direct changes in unreliable indices, and take the measures out of their context. I am not pretending (and will never) that our conclusions are flawless and that there is only one way to reach Rome, but I have today much more confidence in the process to apply with athletes, that I had 13 years ago. Fortunately enough, I didn’t quit HRV in 2004 when submitting my PhD work. We had an uninterrupted series of story twists and surprises together, and since now I know her better, I am happy to grow old with her. For better, or worse! This review paper is dedicated to all the friends and colleagues who made our relationship so enjoyable and more exciting every day. Thank you all!
@HaniAlHaddad2 @jstan85 @theplews1@PaulBLaursen
Stanley J. & Buchheit M. Moderate recovery unnecessary to sustain high stroke volume during interval training, J Sport Sci & Med, 2014, In press.
It has been suggested that the time spent at a high stroke volume (SV) is important for improving maximal cardiac function. The aim of this study was to examine the effect of recovery intensity on cardiovascular parameters during a typical high-intensity interval training (HIIT) session in fourteen well-trained cyclists. Oxygen consumption (VO2), heart rate (HR), SV, cardiac output (Qc), and oxygenation of vastus lateralis (TSI) were measured during a HIIT (3×3 min work period, 2 min recovery) session on two occasions. VO2, HR and Qc were higher during moderate-intensity (60%) compared with low-intensity (30%) (VO2, effect size; ES=+2.6; HR, ES=+2.8; Qc, ES=+2.2) and passive (HR, ES=+2.2; Qc, ES=+1.7) recovery. By contrast, there were no clear differences in SV between the three recovery conditions, with the SV during the two active recovery periods not being substantially different than during exercise (60%, ES=−0.1; 30%, ES=−0.2). To conclude, moderate-intensity recovery may not be required to maintain a high SV during HIIT.
Keywords: high-intensity interval training; cardiac output; cardiac function; arteriovenous oxygen difference
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Buchheit & Mendez-Villanueva. Effects of age, maturity and body dimensions on match running performance in highly-trained under 15 soccer players. Journal of Sports Science, In press
For a discussion about the stats used in this study see the comments here: don’t trust % differences
The aim of the present study was to compare, in 36 highly-trained under 15 soccer players, the respective effects of age, maturity and body dimensions on match running performance. Maximal sprinting (MSS) and aerobic speeds were estimated. Match running performance was analysed with GPS (GPSport, 1 Hz) during 19 international friendly games (n=115 player-files). Total distance and distance covered >16 km/h (D>16 km.h-1) were collected. Players advanced in age and/or maturation, or having larger body dimensions presented greater locomotor (Cohen’s d for MSS: 0.5-1.0, likely to almost certain) and match running performances (D>16 km.h-1: 0.2-0.5, possibly to likely) than their younger, less mature and/or smaller team-mates. These age-, maturation- and body size-related differences were of larger magnitude for field test measures vs. match running performance. Compared with age and body size (unclear to likely), maturation (likely to almost certainly for all match variables) had the greatest impact on match running performance. The magnitude of the relationships between age, maturation and body dimensions and match running performance were position-dependent. Within a single age-group in the present player sample, maturation had a substantial impact on match running performance, especially in attacking players. Coaches may need to consider players’ maturity status when assessing their on-field playing performance.
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Litterature on validation and various use: 032A-VO2000 U of MN validation 032B-VO2000 U of MI validation 033-VO2000 U of Mass validation Byard-VO2000UofMValidationStudy Data Sheet VO2000 M. Buchheit – Parasympathetic reactivation after repeated sprint exercise VO2000 Portable VO2 testing..
Karim Hader, Alberto Mendez-Villanueva, Said Ahmaidi, Ben Williams and Martin
Buchheit. Changes of direction during high-intensity intermittent runs: neuromuscular and metabolic responses. Accepted to BMC Sports Science, Medicine and Rehabilitation on 19 December 2013.
Background: The ability to sustain brief high-intensity intermittent efforts (HIE) is meant to be a major attribute for performance in team sports. Adding changes of direction to HIE is believed to increase the specificity of training drills with respect to game demands. The aim of this study was to investigate the influence of 90°-changes of direction (COD) during HIE on metabolic and neuromuscular responses.
Methods: Eleven male, team sport players (30.5±3.6 y, 81±6 kg, 180± 6cm) performed randomly HIE without (straight-line, 2x[10x 22m]) or with (2x[10x ~16.5m]) two 90°-COD. To account for the time lost while changing direction, the distance for COD runs during HIE was individually adjusted using the ratio between straight-line and COD sprints. Players also performed 2 countermovement (CMJ) and 2 drop (DJ) jumps, during and post HIE. Pulmonary oxygen uptake ( O2), quadriceps and hamstring oxygenation, blood lactate concentration (Δ[La]b), electromyography amplitude (RMS) of eight lower limb muscles and rating of perceived exertion (RPE) were measured for each condition.
Results: During HIE, CODs had no substantial effects on changes in O2, oxygenation, CMJ and DJ performance and RPE (all differences in the changes rated as unclear). Conversely, compared with straight-line runs, COD-runs were associated with a possibly higher Δ[La]b (+9.7±10.4%, with chances for greater/similar/lower values of 57/42/0%). There was also a lower decrease in lateral gastrocnemius (-8.5±9.3%, 1/21/78) and semitendinosus (-11.9 ± 14.6%, 2/13/85) electromyography amplitude; the decrease in electromyography amplitude for the other muscles was not clearly different.
Conclusion: Adding two 90°-CODs on adjusted distance during two sets of HIE is likely to elicit equivalent decreases in CMJ and DJ height, and similar cardiorespiratory and perceptual responses, despite a lower average running speed. A fatigue-induced modification in lower limb control observed with CODs may have elicited a selective reduction of electromyography activity in hamstring muscles and may induce, in turn, a potential mechanical loss of knee stability. Therefore, changing direction during HIE might be an effective training practice 1) to manipulate some components of the acute physiological load of HIE, 2) to promote long-term COD-specific neuromuscular adaptations aimed at improving performance and knee joint stability.
Key Words: cardiorespiratory responses; neuromuscular adjustment; selective activation; knee stabilization.
Full paper available on the Journal Website (open Access)
The 2013 INSEP presentation in English !
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Entretiens de l’INSEP 2013
La planification de l’entraînement. Des modèles anciens aux modèles innovants (2013)
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
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.
We all know that body dimensions affect athletic performance, especially in young players differing in maturation. However, how important is this effect is still unclear, and the available methods to account for differences in body dimensions have not been compared. In this study we compared the Aspire Qatari U15 players with the best french U15 players, and examined how their different body size affected their locomotor performance. The first interesting findings was to see how shorter (-7cm) and lighter (-10 kg) the Qatari are !! As you will also understand if you read all results in details, allometric scaling helps to account for these differences, but not always – body dimensions don’t explain everything ! Feedback appreciated, as always.