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Omid Kazemi, Amir Letafatkar and Paulo H. Marchetti

Context: Several studies report static-stretch-induced deficits and dynamic-stretch performance improvement after intervention. Purpose: To investigate the muscle activation of the forehand and backhand in table tennis players after experiencing static- and dynamic-stretching protocols. Methods: A total of 24 elite male table tennis players (age 22.7 [3.46] y, height 1.78 [0.03] m) were tested before and 0, 10, 20, and 30 min after the 3 conditions (dynamic stretch, static stretch, and no stretch). The MEGA ME6000 (Mega Electronics, Kuopio, Finland) was used to capture the surface EMG data of the anterior deltoid, middle deltoid, posterior deltoid, biceps, and triceps muscles. Muscle activation data of the pretest were compared with posttest 0, 10, 20, and 30 min. These data were also compared between 3 different conditions (dynamic stretch, static stretch, and no stretch). Results: A 2-way repeated-measures analysis of variance indicated significant differences in the forehand and backhand, and Bonferroni test as a post hoc comparison revealed significant differences between the pretest and posttests in several muscles (P < .05). Furthermore, there were significant differences in the posttest between the 3 conditions (P < .05). Conclusions: In general, there was a short-term effect of static- and dynamic-stretching protocols on glenohumeral-joint muscle activation in elite table tennis players. The static and dynamic stretching presented a decrease and increase, respectively, in muscle activation up to 30 min after stretching. In conclusion, the additive and subtractive effects of dynamic- and static-stretching protocols on muscle activation seem to persist after 30 min.

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Justin J. Merrigan, James J. Tufano, Michael Falzone and Margaret T. Jones

Purpose: To identify acute effects of a single accentuated eccentric loading (AEL) repetition on subsequent back-squat kinetics and kinematics with different concentric loads. Methods: Resistance-trained men (N = 21) participated in a counterbalanced crossover design and completed 4 protocols (sets × repetitions at eccentric/concentric) as follows: AEL65, 3 × 5 at 120%/65% 1-repetition maximum (1-RM); AEL80, 3 × 3 at 120%/80% 1-RM; TRA65, 3 × 5 at 65%/65% 1-RM; and TRA80, 3 × 3 at 80%/80% 1-RM. During AEL, weight releasers disengaged from the barbell after the eccentric phase of the first repetition and remained off for the remaining repetitions. All repetitions were performed on a force plate with linear position transducers attached to the barbell, from which eccentric and concentric peak and mean velocity, force, and power were derived. Results: Eccentric peak velocity (−0.076 [0.124] m·s−1; P = .01), concentric peak force (187.8 [284.4] N; P = .01), eccentric mean power (−145.2 [62.0] W; P = .03), and eccentric peak power (−328.6 [93.7] W; P < .01) during AEL65 were significantly greater than TRA65. When collapsed across repetitions, AEL65 resulted in slower eccentric velocity and power during repetition 1 but faster eccentric and concentric velocity and power in subsequent repetitions (P ≤ .04). When comparing AEL80 with TRA80, concentric peak force (133.8 [56.9] N; P = .03), eccentric mean power (−83.57 [38.0] W; P = .04), and eccentric peak power (−242.84 [67.3] W; P < .01) were enhanced. Conclusions: Including a single supramaximal eccentric phase of 120% 1-RM increased subsequent velocity and power with concentric loads of 65% 1-RM, but not 80% 1-RM. Therefore, AEL is sensitive to the magnitude of concentric loads, which requires a large relative difference to the eccentric load, and weight releasers may not need to be reloaded to induce performance enhancement.

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Joel L. Prowting, Debra Bemben, Christopher D. Black, Eric A. Day and Jason A. Campbell

The authors sought to determine whether consuming collagen peptides (CP) enhances musculoskeletal recovery of connective tissues following a damaging exercise bout. Resistance-trained males consumed 15 g/day of CP (n = 7) or placebo (n = 8), and after 7 days, maximal voluntary isometric contraction (MVIC), countermovement jump height, soreness, and collagen turnover were examined. Five sets of 20 drop jumps were performed and outcome measures were collected 24, 48, and 120 hr postexercise. Countermovement jump height was maintained in the CP group at 24 hr (PRE = 39.9 ± 8.8 cm vs. 24 hr = 37.9 ± 8.9 cm, p = .102), whereas the CP group experienced a significant decline at 24 hr (PRE = 40.4 ± 7.9 cm vs. 24 hr = 35.5 ± 6.4 cm, p = .001; d = 0.32). In both groups, muscle soreness was significantly higher than PRE at 24 hr (p = .001) and 48 hr (p = .018) but not at 120 hr (p > .05). MVIC in both legs showed a significant time effect (left: p = .007; right: p = .010) over the 5-day postexercise period. Neither collagen biomarker changed significantly at any time point. CP supplementation attenuated performance decline 24 hr following muscle damage. Acute consumption of CP may provide a performance benefit the day following a bout of damaging exercise in resistance-trained males.

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Carolina Lundqvist

This case report described the use of behavioral activation when a former Olympic athlete developed depression after career termination. Four sessions were conducted, one session each week, followed by a boost session 1 month later. In Session 1, the former Olympic athlete displayed mild-to-moderate depression with anxiety and a low quality of life (Montgomery–Åsberg Depression Rating Scale = 21; Generalized Anxiety Disorder-7 Scale = 17; Brunnsviken Brief Quality of Life Scale = 44). By Session 3, the Olympic athlete no longer met the diagnostic criteria for clinical depression or anxiety (Montgomery–Åsberg Depression Rating Scale = 2; Generalized Anxiety Disorder-7 Scale = 7) and the quality of life was improved (Brunnsviken Brief Quality of Life Scale = 60). Follow-up assessments 1-year posttreatment confirmed that the former Olympic athlete continued to improve (Montgomery–Åsberg Depression Rating Scale = 0; Generalized Anxiety Disorder-7 Scale = 0; Brunnsviken Brief Quality of Life Scale = 96). This case report discusses the benefits of proactive support to elite athletes and the use of established clinical psychological treatments, for example, behavioral activation, when athletes develop health-related conditions.

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Stefano Montanari, Mehmet A. S¸ahin, Ben J. Lee, Sam D. Blacker and Mark E.T. Willems

Supplementation with anthocyanin-rich blackcurrant increases blood flow, cardiac output, and stroke volume at rest. It is not known whether cardiovascular responses can be replicated over longer timeframes in fed trained cyclists. In a randomized, double-blind, crossover design, 13 male trained cyclists (age 39 ± 10 years, V˙O2max 55.3 ± 6.7 ml·kg−1·min−1) consumed two doses of New Zealand blackcurrant (NZBC) extract (300 and 600 mg/day for 1 week). Cardiovascular parameters were measured during rest and submaximal cycling (65% V˙O2max) on day 1 (D1), D4, and D7. Data were analyzed with an RM ANOVA using dose (placebo vs. 300 vs. 600 mg/day) by time point (D1, D4, and D7). Outcomes from placebo were averaged to determine the coefficient of variation within our experimental model, and 95% confidence interval (CI) was examined for differences between placebo and NZBC. There were no differences in cardiovascular responses at rest between conditions and between days. During submaximal exercise, no positive changes were observed on D1 and D4 after consuming NZBC extract. On D7, intake of 600 mg increased stroke volume (3.08 ml, 95% CI [−2.08, 8.26]; d = 0.16, p = .21), cardiac output (0.39 L/min, 95% CI [−1.39, .60]; d = 0.14, p = .40) (both +2.5%), and lowered total peripheral resistance by 6.5% (−0.46 mmHg·min/ml, 95% CI [−1.80, .89]; d = 0.18, p = .46). However, these changes were trivial and fell within the coefficient of variation of our study design. Therefore, we can conclude that NZBC extract was not effective in enhancing cardiovascular function during rest and submaximal exercise in endurance-trained fed cyclists.

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Michael McDougall, Noora Ronkainen, David Richardson, Martin Littlewood and Mark Nesti

In sport psychology, organizational culture is usually depicted as shared, consistent, and clear—the glue that holds people together so they can achieve success. There is, however, growing discontent in sport psychology with this idea of culture and extensive critiques in other academic domains that suggest this perspective is limited. Accordingly, the authors draw on narrative interviews with participants (n = 7) from different areas of sport and use Martin and Meyerson’s three perspective (integration, differentiation, and fragmentation) approach to culture alongside thematic analysis to reconstruct three “ideal cases” that exemplify each perspective. The findings emphasize a different pattern of meaning in each actors’ narrative and suggest the need to develop a broader, more inclusive concept of culture, so as not to minimize or dismiss cultural content that is not obviously shared, clear, or created by leadership; a course of action that can enhance both research and practice in the area.

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Ava Farley, Gary J. Slater and Karen Hind

Athletic populations require high-precision body composition assessments to identify true change. Least significant change determines technical error via same-day consecutive tests but does not integrate biological variation, which is more relevant for longitudinal monitoring. The aim of this study was to assess biological variation using least significant change measures from body composition methods used on athletes, including surface anthropometry (SA), air displacement plethysmography (BOD POD), dual-energy X-ray absorptiometry (DXA), and bioelectrical impedance spectroscopy (BIS). Thirty-two athletic males (age = 31 ± 7 years; stature = 183 ± 7 cm; mass = 92 ± 10 kg) underwent three testing sessions over 2 days using four methods. Least significant change values were calculated from differences in Day 1 Test 1 versus Day 1 Test 2 (same-day precision), as well as Day 1 Test 1 versus Day 2 (consecutive-day precision). There was high agreement between same-day and consecutive-day fat mass and fat-free mass measurements for all methods. Consecutive-day precision error in comparison with the same-day precision error was 50% higher for fat mass estimates from BIS (3,607 vs. 2,331 g), 25% higher from BOD POD (1,943 vs. 1,448 g) and DXA (1,615 vs. 1,204 g), but negligible from SA (442 vs. 586 g). Consecutive-day precision error for fat-free mass was 50% higher from BIS (3,966 vs. 2,276 g) and SA (1,159 vs. 568 g) and 25% higher from BOD POD (1,894 vs. 1,450 g) and DXA (1,967 vs. 1,461 g) than the same-day precision error. Precision error in consecutive-day analysis considers both technical error and biological variation, enhancing the identification of small, yet significant changes in body composition of resistance-trained male athletes. Given that change in physique is likely to be small in this population, the use of DXA, BOD POD, or SA is recommended.

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Kendra Nelson Ferguson, Craig Hall and Alison Divine

The study aimed to determine whether athletes who practice biofeedback are able to self-regulate by reaching resonance frequency and gaining physiological control quicker than if practice time integrates imagery or a rest period. Intervention effectiveness (e.g., intervention length, time spent training) was also explored. Twenty-seven university athletes were assigned to one of three groups: (a) biofeedback (i.e., continuous training), (b) biofeedback/imagery (i.e., interspersed with imagery), and (c) biofeedback/rest (i.e., interspersed with a rest period). Five biofeedback sessions training respiration rate, heart rate variability, and skin conductance were conducted. A repeated-measure analysis of variance showed a significant interaction between groups over time (p ≤ .05) for respiration rate, heart rate variability, and skin conductance, indicating that resonance frequency and physiological control was regained following imagery or a rest period. Postmanipulation check data found intervention length and training time to be sufficient. Combining imagery with biofeedback may optimize management of psychophysiological processes.

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Alisia G.T.T. Tran

With the aim of supporting anxiety screening of student-athletes, this study examined the psychometric performance of the GAD-7 and GAD-2 for assessing anxiety and other clinical mental health concerns (depression, past-year and recent suicidality) in student-athletes. Data from intercollegiate varsity athletes (N = 7,584) were drawn from the Healthy Minds Study. Reliability estimates were good in the sample. Area under the curve values were excellent for anxiety and fair to good for depression and suicidality. Across all clinical indicators, a cutoff of 6 (GAD-7) and 2 (GAD-2), respectively, yielded the most balanced sensitivity and specificity rates. Both measures positively correlated with functional impairment, academic impact, and perceived mental health and negatively correlated with positive mental health. Overall, results supported the reliability, accuracy, and construct validity of the GAD-7 and GAD-2 in a national student-athlete sample. Discussion focuses on clinical implications and practical usage of the GAD-7 and GAD-2 with student-athletes.