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Sebastian Altfeld, Paul Schaffran, Jens Kleinert and Michael Kellmann

(Vulnerability-Stress Model; Liebermann, 1986 ). According to this model, individuals with a higher vulnerability show higher rates of psychological illnesses compared to those with a lower vulnerability when exposed to identical living conditions ( Miller, Chen, & Zhou, 2007 ). Negative Cycle: Why Is Recovery

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Jonathan D.C. Leeder, Ken A. van Someren, David Gaze, Andrew Jewell, Nawed I.K. Deshmukh, Iltaf Shah, James Barker and Glyn Howatson

Purpose:

This investigation aimed to ascertain a detailed physiological profile of recovery from intermittentsprint exercise of athletes familiar with the exercise and to investigate if athletes receive a protective effect on markers of exercise-induced muscle damage (EIMD), inflammation, and oxidative stress after a repeated exposure to an identical bout of intermittent-sprint exercise.

Methods:

Eight well-trained male team-sport athletes of National League or English University Premier Division standard (mean ± SD age 23 ± 3 y, VO2max 54.8 ± 4.6 mL · kg−1 · min−1) completed the Loughborough Intermittent Shuttle Test (LIST) on 2 occasions, separated by 14 d. Maximal isometric voluntary contraction (MIVC), countermovement jump (CMJ), creatine kinase (CK), C-reactive protein (CRP), interleukin-6 (IL-6), F2-isoprostanes, and muscle soreness (DOMS) were measured before and up to 72 h after the initial and repeated LISTs.

Results:

MIVC, CMJ, CK, IL-6, and DOMS all showed main effects for time (P < .05) after the LIST, indicating that EIMD was present. DOMS peaked at 24 h after LIST 1 (110 ± 53 mm), was attenuated after LIST 2 (56 ± 39 mm), and was the only dependent variable to demonstrate a reduction in the second bout (P = .008). All other markers indicated that EIMD did not differ between bouts.

Conclusion:

Well-trained games players experienced EIMD after exposure to both exercise tests, despite being accustomed to the exercise type. This suggests that well-trained athletes receive a very limited protective effect from the first bout.

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Justin P. Guilkey, Brandon Dykstra, Jennifer Erichsen and Anthony D. Mahon

Purpose:

This study examined heart rate recovery (HRR) and heart rate variability (HRV) following maximal exercise in lean (<85th percentile age- and sex-BMI percentile; n = 11 (♂=5; ♀=6); 10.1 ± 0.7 years) and overweight (≥85th age- and sex-BMI percentile; n = 11 (♂=5; ♀=6); 10.5 ± 1.2 years) children.

Method:

Participants completed a 10-min rest, followed by a graded exercise test to maximal effort. HRV, in the time and frequency domains, was assessed during rest and recovery. Also during recovery, one-minute HRR and the time constant of a monoexponential line of best fit (HRRt) were determined.

Results:

There were no significant differences in one-minute HRR and HRRt between the lean (56 ± 7 beats∙min-1 and 160.4 ± 80.1 s, respectively) and overweight (51 ± 16 beats∙min-1 and 141.1 ± 58.1 s, respectively) groups. There also were no significant interactions between groups from rest to recovery for any HRV variables. Root mean square of successive differences (RMSSD) and high frequency power (HF) during recovery was 2.05 ± 0.49 ms and 3.30 ± 1.02 ms2 in the lean children, respectively. In the overweight children, RMSSD and HF were 1.88 ± 0.65 ms and 2.94 ± 1.27 ms2, respectively.

Conclusion:

HRR and HRV findings suggest there are no differences in autonomic function during recovery from maximal exercise in lean and obese 8- to 12-year old children.

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Takeshi Kokubo, Yuta Komano, Ryohei Tsuji, Daisuke Fujiwara, Toshio Fujii and Osamu Kanauchi

, including antigen presentation and antiviral infection ( Cervantes-Barragan et al., 2012 ; Siegal et al., 1999 ); however, its role during exercise and presentation of related symptoms is unclear. This preclinical study was designed to study the mechanism of attenuation of fatigue and recovery by LC

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Laurent Mourot, Nicolas Fabre, Erik Andersson, Sarah Willis, Martin Buchheit and Hans-Christer Holmberg

Postexercise heart-rate (HR) recovery (HRR) indices have been associated with running and cycling endurance-exercise performance. The current study was designed (1) to test whether such a relationship also exists in the case of cross-country skiing (XCS) and (2) to determine whether the magnitude of any such relationship is related to the intensity of exercise before obtaining HRR indices. Ten elite male cross-country skiers (mean ± SD; 28.2 ± 5.4 y, 181 ± 8 cm, 77.9 ± 9.4 kg, 69.5 ± 4.3 mL · min−1 · kg−1 maximal oxygen uptake [VO2max]) performed 2 sessions of roller-skiing on a treadmill: a 2 × 3-km time trial and the same 6-km at an imposed submaximal speed followed by a final 800-m time trial. VO2 and HR were monitored continuously, while HRR and blood lactate (BLa) were assessed during 2 min immediately after each 6-km and the 800-m time trial. The 6-km time-trial time was largely negatively correlated with VO2max and BLa. On the contrary, there was no clear correlation between the 800-m time-trial time and VO2, HR, or BLa. In addition, in no case was any clear correlation between any of the HRR indices and performance time or VO2max observed. These findings confirm that XCS performance is largely correlated with VO2max and the ability to tolerate high levels of BLa; however, postexercise HRR showed no clear association with performance. The homogeneity of the group of athletes involved and the contribution of the arms and upper body to the exercise preceding determination of HRR may explain this absence of a relationship.

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Sarah Kölling, Rob Duffield, Daniel Erlacher, Ranel Venter and Shona L. Halson

Sleep is increasingly gaining attention among sport scientists and practitioners as an important element to optimize sport performance and recovery. In fact, the critical importance of sleep’s restorative effects in daily life makes it an integral part of the recovery processes for athletes. 1 For

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Júlio A. Costa, João Brito, Fábio Y. Nakamura, Eduardo M. Oliveira, Ovidio P. Costa and António N. Rebelo

Sleep is considered the most important and accessible daily recovery strategy. However, despite its importance to psychological and physiological recovery, athletes often sleep less than recommended. 1 Although a minimum of 7 hours of sleep per night is generally recommended to promote optimal

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J.C. Siegler, J. Bell-Wilson, C. Mermier, E. Faria and R.A. Robergs

The purpose of this study was to profile the effect of active versus passive recovery on acid-base kinetics during multiple bouts of intense exercise. Ten males completed two exercise trials. The trials consisted of three exercise bouts to exhaustion with either a 12 min active (20% workload max) or passive recovery between bouts. Blood pH was lower in the passive (p) recovery compared to active (a) throughout the second and third recovery periods [second recovery: 7.18 ± 0.08 to 7.24 ± 0.09 (p), 7.23 ± 0.07 to 7.32 ± 0.07 (a), P < 0.05; third recovery: 7.17 ± 0.08 to 7.22 ± 0.09 (p), 7.23 ± 0.08 to 7.32 ± 0.08 (a), P < 0.05]. Exercise performance times did not differ between recovery conditions (P = 0.28). No difference was found between conditions for recovery kinetics (slope and half-time to recovery). Subsequent performance during multiple bouts of intense exercise to exhaustion may not be influenced by blood acidosis or mode of recovery.

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Oliver R. Barley, Dale W. Chapman, Georgios Mavropalias and Chris R. Abbiss

) may impact competitive performance by impairing repeat-effort capacities, 7 combat sports–specific performance, 9 – 11 and muscular performance 8 , 12 – 13 following recovery periods of 3 to 5 hours and in some cases up to 24 hours. 7 Heat acclimation has been shown to mitigate the negative

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Laura E. Juliff, Jeremiah J. Peiffer and Shona L. Halson

Despite the acknowledged importance of sleep for performance and recovery, 1 athletes commonly experience sleep loss following late competitions. 2 – 4 Specifically, team-sport athletes such as male footballers 4 and Australian rules footballers 5 , 6 have reported reduced sleep quantities of