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Dieter Böning

In modern societies there is strong belief in scientific progress, but, unfortunately, a parallel partial regress occurs because of often avoidable mistakes. Mistakes are mainly forgetting, erroneous theories, errors in experiments and manuscripts, prejudice, selected publication of “positive” results, and fraud. An example of forgetting is that methods introduced decades ago are used without knowing the underlying theories: Basic articles are no longer read or cited. This omission may cause incorrect interpretation of results. For instance, false use of actual base excess instead of standard base excess for calculation of the number of hydrogen ions leaving the muscles raised the idea that an unknown fixed acid is produced in addition to lactic acid during exercise. An erroneous theory led to the conclusion that lactate is not the anion of a strong acid but a buffer. Mistakes occur after incorrect application of a method, after exclusion of unwelcome values, during evaluation of measurements by false calculations, or during preparation of manuscripts. Co-authors, as well as reviewers, do not always carefully read papers before publication. Peer reviewers might be biased against a hypothesis or an author. A general problem is selected publication of positive results. An example of fraud in sports medicine is the presence of doped subjects in groups of investigated athletes. To reduce regress, it is important that investigators search both original and recent articles on a topic and conscientiously examine the data. All co-authors and reviewers should read the text thoroughly and inspect all tables and figures in a manuscript.

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Cory W. Baumann, Jeffrey C. Rupp, Christopher P. Ingalls and J. Andrew Doyle

Purpose:

The purpose of this study was to examine the relationship between anaerobic characteristics and 5-km-race performance in trained female cross-country runners (N = 13).

Methods:

The runners performed 50-m sprints and a 5-km time trial on an outdoor 400-m track and maximal anaerobic (MART) and aerobic running tests on a motorized treadmill. Anaerobic characteristics were determined by the mean velocity of the 50-m sprint (v 50m) and the peak velocity in the MART (v MART). The aerobic characteristics were obtained during the aerobic treadmill test and included maximal oxygen uptake (VO2max), running economy, and ventilatory threshold (VT).

Results:

Both the v MART (r = .69, P < .01) and VO2max (r = .80, P < .01) correlated with the mean velocity of the 5-km (v 5km). A multiple-linear-regression analysis revealed that the combination of VO2max, v MART, and VT explained 81% (R 2 = .81, P < .001) of the variation seen in the v 5km. The v MART accounted for 31% of the total shared variance, while the combination of VO2max and VT explained the remaining 50%.

Conclusions:

These results suggest that among trained female runners who are relatively matched, anaerobic energy production can effectively discriminate the v 5km and explain a significant amount of the variation seen in 5-km-race performance.

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Darren Burgess, Geraldine Naughton and Kevin Norton

Purpose:

The understanding of the gap between Under 18 y (U18) and senior-level competition and the evolution of this gap in Australian Football lack a strong evidence base. Despite the multimillion dollars invested in recruitment, scientific research on successful transition is limited. No studies have compared individual players’ movement rate, game statistics and ball speed in U18 and senior competition of the Australian Football League across time. This project compared differences in player movement and ball speed between matches from senior AFL competitive matches and U18 players in the 2003 and 2009 seasons.

Methods:

TrakPerformance Software and Global Positioning System (GPS) technology were used to analyze the movement of players, ball speed and game statistics. ANOVA compared the two levels of competition over time.

Results:

Observed interactions for distance traveled per minute of play (P = .009), number of sprints per minute of play (P < .001), time spent at sprint speed in the game (P < .001), time on field (P < .001), and ball speed (P < .001) were found. Subsequent analysis identified increases in movement patterns in senior AFL competition in 2009 compared with the same level of competition in 2003 and U18 players in 2003 and 2009.

Conclusions:

Senior AFL players in 2009 were moving further, sprinting relatively more frequently, playing less time and playing at game speeds significantly greater than the same senior competition in 2003 as well as compared with both cohorts of U18 players.

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John K. Malone, Catherine Blake and Brian Caulfield

Purpose:

To investigate the use of neuromuscular electrical stimulation (NMES) during acute recovery between 2 bouts of maximal aerobic exercise.

Methods:

On 3 separate days, 19 trained male cyclists (28 ± 7 y, 76.4 ± 10.4 kg, power output at maximal aerobic power [pVo2max] 417 ± 44 W) performed a 3-min maximal cycling bout at 105% PVo2max before a 30-min randomly assigned recovery intervention of passive (PAS: resting), active (ACT: 30% PVo2max), or NMES (5 Hz, 4 pulses at 500 μs). Immediately afterward, a cycle bout at 95% PVo2max to exhaustion (TLIM) was performed. Heart rate (HR) and blood lactate (BLa) were recorded at designated time points. Data were analyzed using repeated-measures ANOVA with a Tukey honestly significantly different post hoc test. Statistical significance threshold was P < .05.

Results:

The TLIM was significantly shorter for NMES than for ACT (199.6 ± 69.4 s vs 250.7 ± 105.5 s: P = .016) but not PAS recovery (199.6 ± 69.4 s vs 216.4 ± 77.5 s: P = .157). The TLIM was not significantly different between ACT and PAS (250.7 ± 105.5 s vs 216.4 ± 77.5 s: P = .088). The decline in BLa was significantly greater during ACT than NMES and PAS recovery (P < .001), with no difference between NMES and PAS. In addition, HR was significantly higher during ACT than NMES and PAS recovery (P < .001), with no difference between NMES and PAS.

Conclusions:

NMES was less effective than ACT and comparable to PAS recovery when used between 2 bouts of maximal aerobic exercise in trained male cyclists.

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We, the Editors and Publishers of the International Journal of Sports Physiology and Performance, have withdrawn the following article in whole: Plews, DJ, Laursen, PB. Training intensity distribution over a four-year cycle in Olympic champion rowers: different roads lead to Rio [version of record published online ahead of print September 27, 2017]. Int J Sports Physiol Perform. doi: 10.1123/ijspp.2017-0343. The Editorial Office was contacted with the request to withdraw this article informing the Editor-in-Chief that the data in this article were not permissible to use due to undisclosed contractual obligations.