Purpose: To determine the effect of high- versus low-intensity training in the heat and ensuing taper period in the heat on endurance performance. Methods: In total, 19 well-trained triathletes undertook 5 days of normal training and a 1-wk taper including either low- (heat acclimation [HA-L], n = 10) or high-intensity (HA-H, n = 9) training sessions in the heat (30°C, 50% relative humidity). A control group (n = 10) reproduced their usual training in thermoneutral conditions. Indoor 20-km cycling time trials (35°C, 50% relative humidity) were performed before (Pre) and after the main heat exposure (Mid) and after the taper (Post). Results: Power output remained stable in the control group from Pre to Mid (effect size: −0.10 [0.26]) and increased from Mid to Post (0.18 [0.22]). The HA-L group demonstrated a progressive increase in performance from Pre to Mid (0.62 [0.33]) and from Mid to Post (0.53 [0.30]), alongside typical physiological signs of HA (reduced core temperature and heart rate and increased body-mass loss). While the HA-H group presented similar adaptations, increased perceived fatigue and decreased performance at Mid (−0.35 [0.26]) were evidenced and reversed at Post (0.50 [0.20]). No difference in power output was reported at Post between the HA-H and control groups. Conclusion: HA-H can quickly induce functional overreaching in nonacclimatized endurance athletes. As it was associated with a weak subsequent performance supercompensation, coaches and athletes should pay particular attention to training monitoring during a final preparation in the heat and reduce training intensity when early signs of functional overreaching are identified.
Search Results
You are looking at 1 - 10 of 10 items for
- Author: Yann Le Meur x
- Refine by Access: All Content x
Cyril Schmit, Rob Duffield, Christophe Hausswirth, Jeanick Brisswalter, and Yann Le Meur
Cyril Granier, Chris R. Abbiss, Anaël Aubry, Yvon Vauchez, Sylvain Dorel, Christophe Hausswirth, and Yann Le Meur
Purpose: To characterize the physiological profiles of elite cross-country mountain-bike (XCO-MTB) cyclists and to examine their pacing and power-output (PO) distribution during international races. Methods: Over 2 competitive seasons, 8 male XCO-MTB cyclists (VO2max 79.9 [5.2] mL·min−1·kg−1, maximal aerobic power [MAP] 411 [18] W and 6.3 [0.4] W·kg−1) regularly undertook incremental tests to assess their PO and heart rate (HR) at first and second ventilatory thresholds (VT1 and VT2) and at VO2max. During the same period, their PO, HR, speed, and cadence were recorded over 13 international races (total of 30 recorded files). Results: Mean PO, speed, cadence, and HR during the races were 283 (22) W (4.31 [0.32] W·kg−1, 68% [5%] MAP), 19.7 (2.1) km·h−1, 68 (8) rpm, and 172 (11) beats·min−1 (91% [2%] HRmax), respectively. The average times spent below 10% of MAP, between 10% of MAP and VT1, between VT1 and VT2, between VT2 and MAP, and above MAP were 25% (5%), 21% (4%), 13% (3%), 16% (3%), and 26% (5%), respectively. Both speed and PO decreased from the start loop to lap 1 before stabilizing until the end of the race. Conclusions: Elite off-road cyclists demonstrated typical values of world-class endurance cyclists with an excellent power-to-mass ratio. This study demonstrated that XCO-MTB races are performed at higher intensities than reported in previous research and are characterized by a fast start followed by an even pace.
Yann Le Meur, Martin Buchheit, Anaël Aubry, Aaron J Coutts, and Christophe Hausswirth
Purpose:
Faster heart-rate recovery (HRR) after high to maximal exercise (≥90% of maximal heart rate) has been reported in athletes suspected of functional overreaching (f-OR). This study investigated whether this response would also occur at lower exercise intensity.
Methods:
Responses of HRR and rating of perceived exertion (RPE) were compared during an incremental intermittent running protocol to exhaustion in 20 experienced male triathletes (8 control subjects and 13 overload subjects led to f-OR) before and immediately after an overload training period and after a 1-wk taper.
Results:
Both groups demonstrated an increase in HRR values immediately after the training period, but this change was very likely to almost certainly larger in the f-OR group at all running intensities (large to very large differences, eg, +16 ± 7 vs +3 ± 5 beats/min, in the f-OR and control groups at 11 km/h, respectively). The highest between-groups differences in changes in HRR were reported at 11 km/h (13 ± 4 beats/min) and 12 km/h (10 ± 6 beats/min). A concomitant increase in RPE at all intensities was reported only in the f-OR group (large to extremely large differences, +2.1 ± 1.5 to +0.7 ± 1.5 arbitrary units).
Conclusion:
These findings confirm that faster HRR does not systematically predict better physical performance. However, when interpreted in the context of the athletes’ fatigue state and training phase, HRR after submaximal exercise may be more discriminant than HRR measures taken after maximal exercise for monitoring f-OR. These findings may be applied in practice by regularly assessing HRR after submaximal exercise (ie, warm-up) for monitoring endurance athletes’ responses to training.
Cyril Schmit, Rob Duffield, Christophe Hausswirth, Aaron J. Coutts, and Yann Le Meur
Purpose:
To describe the effect of the initial perceptual experience from heat familiarization on the pacing profile during a freepaced endurance time trial (TT) compared with temperate conditions.
Methods:
Two groups of well-trained triathletes performed two 20-km TTs in either hot (35°C and 50% relative humidity [RH], n = 12) or temperate (21°C and 50% RH, n = 22) conditions, after standardization of training for each group before both trials. To ensure no physiological acclimation differences between conditions, the TTs for both groups were separated by 11 ± 4 d.
Results:
Performance improvement in the heat (11 ± 24 W) from the 1st to 2nd trial appeared comparable to that in temperate conditions (8 ± 14 W, P = .67). However, the specific alteration in pacing profile in the heat was markedly different than temperate conditions, with a change from “positive” to an “even” pacing strategy.
Conclusions:
Altered perceptions of heat during heat familiarization, rather than physiological acclimatization per se, may mediate initial changes in pacing and TT performance in the heat. These results highlight the need for athletes without time for sufficient heat acclimatization to familiarize themselves with hot conditions to reduce the uncertainty from behavior-based outcomes that may impede performance.
Daniel J. Plews, Paul B. Laursen, Yann Le Meur, Christophe Hausswirth, Andrew E. Kilding, and Martin Buchheit
Purpose:
To establish the minimum number of days that heart-rate-variability (HRV, ie, the natural logarithm of square root of the mean sum of the squared differences between R-R intervals, Ln rMSSD) data should be averaged to achieve correspondingly equivalent results as data averaged over a 1-wk period.
Methods:
Standardized changes in Ln rMSSD between different phases of training (normal training, functional overreaching (FOR), overall training, and taper) and the correlation coefficients of percentage changes in performance vs changes in Ln rMSSD were compared when averaging Ln rMSSD from 1 to 7 d, randomly selected within the week.
Results:
Standardized Ln rMSSD changes (90% confidence limits, CL) from baseline to overload (FOR) were 0.20 ± 0.28, 0.33 ± 0.26, 0.49 ± 0.33, 0.48 ± 0.28, 0.47 ± 0.26, 0.45 ± 0.26, and 0.43 ± 0.29 on days 1 to 7, respectively. Correlations (90% CL) over the same time sequence and training phase were –.02 ± .23, –.07 ± .23, –.17 ± .22, –.25 ± .22, –.26 ± .22, –.28 ± .21, and –.25 ± .22 on days 1 to 7. There were almost perfect quadratic relationships between standardized changes/r values vs the number of days Ln rMSSD was averaged (r 2 = .92 and .97, respectively) in trained triathletes during FOR. This indicates a plateau in the increase in standardized changes/r values’ magnitude after 3 and 4 d, respectively, in trained triathletes.
Conclusion:
Practitioners using HRV to monitor training adaptation should use a minimum of 3 (randomly selected) valid data points per week.
Yann Le Meur, Thierry Bernard, Sylvain Dorel, Chris R. Abbiss, Gérard Honnorat, Jeanick Brisswalter, and Christophe Hausswirth
Purpose:
The purpose of the present study was to examine relationships between athlete’s pacing strategies and running performance during an international triathlon competition.
Methods:
Running split times for each of the 107 finishers of the 2009 European Triathlon Championships (42 females and 65 males) were determined with the use of a digital synchronized video analysis system. Five cameras were placed at various positions of the running circuit (4 laps of 2.42 km). Running speed and an index of running speed variability (IRSVrace) were subsequently calculated over each section or running split.
Results:
Mean running speed over the frst 1272 m of lap 1 was 0.76 km-h–1 (+4.4%) and 1.00 km-h–1 (+5.6%) faster than the mean running speed over the same section during the three last laps, for females and males, respectively (P < .001). A significant inverse correlation was observed between RSrace and IRSVrace for all triathletes (females r = -0.41, P = .009; males r = -0.65, P = .002; and whole population -0.76, P = .001). Females demonstrated higher IRSVrace compared with men (6.1 ± 0.5 km-h–1 and 4.0 ± 1.4 km-h–1, for females and males, respectively, P = .001) due to greater decrease in running speed over uphill sections.
Conclusions:
Pacing during the run appears to play a key role in high-level triathlon performance. Elite triathletes should reduce their initial running speed during international competitions, even if high levels of motivation and direct opponents lead them to adopt an aggressive strategy.
Bruno Marrier, Yann Le Meur, Cédric Leduc, Julien Piscione, Mathieu Lacome, Germain Igarza, Christophe Hausswirth, Jean-Benoît Morin, and Julien Robineau
Purpose: To describe the training periodization in rugby sevens players competing in the World Rugby Sevens Series during a non-Olympic season. Methods: Workload data were collected over a 33-wk period in 12 male players participating in a full competitive season. Workload was quantified using session rating of perceived exertion and global positioning system–derived data during training and competition. Self-reported well-being was assessed using a questionnaire. Each variable was analyzed weekly and through 5 mesocycles (preseason, in-season 1–4), each of which ended with competition blocks. Results: The perceived load decreased throughout the season for the full squad (−68% [26%] between preseason and final competitive block, large effect) and when unavailable players were removed from the analysis (−38% [42%], moderate). Weekly perceived load was highly variable, with a typical periodization in 4 phases during each mesocycle (regeneration, training overload, taper, and competition). During the preseason, the workload was higher during the overload training phase than during the competitive period (range: +23% to +59%, large to very large, for the distance covered above individual maximal aerobic speed and the number of accelerations). This observation no longer persisted during the season. The well-being score decreased almost certainly from in-season 3 (moderate). Conclusions: These results highlighted the apparent difficulty in maintaining high-load training periods throughout the season in players engaged on the World Rugby Sevens Series despite ∼4–7 training weeks separating each competitive block. This observation was likely explained by the difficulties inherent to the World Rugby Sevens Series (risk of contact injury, calendar, and multiple long-haul travel episodes) and potentially by limited squad-rotation policies.
Bruno Marrier, Julien Robineau, Julien Piscione, Mathieu Lacome, Alexis Peeters, Christophe Hausswirth, Jean-Benoît Morin, and Yann Le Meur
Peaking for major competition is considered critical for maximizing team-sport performance. However, there is little scientific information available to guide coaches in prescribing efficient tapering strategies for team-sport players.
Purpose:
To monitor the changes in physical performance in elite team-sport players during a 3-wk taper after a preseason training camp.
Methods:
Ten male international rugby sevens players were tested before (Pre) and after (Post) a 4-wk preseason training camp focusing on high-intensity training and strength training with moderate loads and once each week during a subsequent 3-wk taper. During each testing session, midthigh-pull maximal strength, sprint-acceleration mechanical outputs, and performance, as well as repeated-sprint ability (RSA), were assessed.
Results:
At Post, no single peak performance was observed for maximal lower-limb force output and sprint performance, while RSA peaked for only 1 athlete. During the taper, 30-m-sprint time decreased almost certainly (–3.1% ± 0.9%, large), while maximal lower-limb strength and RSA, respectively, improved very likely (+7.7% ± 5.3%, small) and almost certainly (+9.0% ± 2.6%, moderate). Of the peak performances, 70%, 80%, and 80% occurred within the first 2 wk of taper for RSA, maximal force output, and sprint performance, respectively.
Conclusions:
These results show the sensitivity of physical qualities to tapering in rugby sevens players and suggest that an ~1- to 2-wk tapering time frame appears optimal to maximize the overall physical-performance response.
Bruno Marrier, Yann Le Meur, Julien Robineau, Mathieu Lacome, Anthony Couderc, Christophe Hausswirth, Julien Piscione, and Jean-Benoît Morin
Purpose:
To compare the sensitivity of a sprint vs a countermovement-jump (CMJ) test after an intense training session in international rugby sevens players, as well as analyze the effects of fatigue on sprint acceleration.
Methods:
Thirteen international rugby sevens players completed two 30-m sprints and a set of 4 repetitions of CMJ before and after a highly demanding rugby sevens training session.
Results:
Change in CMJ height was unclear (–3.6%; ±90% confidence limits 11.9%. Chances of a true positive/trivial/negative change: 24/10/66%), while a very likely small increase in 30-m sprint time was observed (1.0%; ±0.7%, 96/3/1%). A very likely small decrease in the maximum horizontal theoretical velocity (V0) (–2.4; ±1.8%, 1/4/95%) was observed. A very large correlation (r = –.79 ± .23) between the variations of V0 and 30-m-sprint performance was also observed. Changes in 30-m sprint time were negatively and very largely correlated with the distance covered above the maximal aerobic speed (r = –.71 ± .32).
Conclusions:
The CMJ test appears to be less sensitive than the sprint test, which casts doubts on the usefulness of a vertical-jump test in sports such as rugby that mainly involve horizontal motions. The decline in sprint performance relates more to a decrease in velocity than in force capability and is correlated with the distance covered at high intensity.
Bruno Marrier, Alexandre Durguerian, Julien Robineau, Mounir Chennaoui, Fabien Sauvet, Aurélie Servonnet, Julien Piscione, Bertrand Mathieu, Alexis Peeters, Mathieu Lacome, Jean-Benoit Morin, and Yann Le Meur
Purpose: Preconditioning strategies are considered opportunities to optimize performance on competition day. Although investigations conducted in rugby players on the effects of a morning preconditioning session have been done, additional work is warranted. The aim of this study was to monitor changes in physical and psychophysiological indicators among international Rugby-7s players after a priming exercise. Methods: In a randomized crossover design, 14 under-18 international Rugby-7s players completed, at 8:00 AM, a preconditioning session consisting of a warm-up followed by small-sided games, accelerations, and 2 × 50-m maximal sprints (Experimental), or no preloading session (Control). After a 2-h break, the players performed a set of six 30-m sprints and a Rugby-7s match. Recovery–stress state and salivary stress-marker levels were assessed before the preloading session (Pre), immediately after the preloading session (Post 1), before the testing session (Post 2), and after the testing session (Post 3). Results: Experimental–Control differences in performance across a repeated-sprint test consisting of six 30-m sprints were very likely trivial (+0.2, ±0.7%, 3/97/1%). During the match, the total distance covered and the frequency of decelerations were possibly lower (small) in Experimental compared with Control. Differences observed in the other parameters were unclear or possibly trivial. At Post 2, the perceived recovery–stress state was improved (small difference) in Experimental compared with Control. No difference in salivary cortisol response was observed, while the preconditioning session induced a higher stimulation of salivary testosterone and α-amylase. Conclusions: The players’ ability to repeat sprints and physical activity in match play did not improve, but their psychophysiological state was positively affected after the present preconditioning session.
