Context: Patients with anterior cruciate ligament (ACL) tears are likely to have deficient dynamic postural stability compared with healthy sex- and age-matched controls. Objectives: To test the hypothesis that patients undergoing ACL reconstruction have decreased dynamic postural stability compared with matched healthy controls. Design: Prospective case-control study. Setting: Orthopedic sports medicine and physical therapy clinics. Patients or Other Participants: Patients aged 20 years and younger with an ACL tear scheduled for reconstruction were enrolled prospectively. Controls were recruited from local high schools and colleges via flyers. Interventions: Patients underwent double-stance dynamic postural stability testing prior to surgery, recording time to failure and dynamic motion analysis (DMA) scores. Patients were then matched with healthy controls. Main Outcome Measures: Demographics, time to failure, and DMA scores were compared between groups. Results: A total of 19 females and 12 males with ACL tears were matched with controls. Individuals with ACL tears were more active (Marx activity score: 15.7 [1.0] vs 10.8 [4.9], P < .001); had shorter times until test failure (84.4 [15.8] vs 99.5 [14.5] s, P < .001); and had higher (worse) DMA scores (627  vs 481 , P < .001), indicating less dynamic postural stability. Six patients with ACL deficiency (1 male and 5 females) demonstrated lower (better) DMA scores than their controls, and another 7 (4 males and 3 females) were within 20% of controls. Conclusions: Patients undergoing ACL reconstruction had worse global dynamic postural stability compared with well-matched controls. This may represent the effect of the ACL injury or preexisting deficits that contributed to the injury itself. These differences should be studied further to evaluate their relevance to ACL injury risk, rehabilitation, and return to play.
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Jonathon R. Staples, Kevin A. Schafer, Matthew V. Smith, John Motley, Mark Halstead, Andrew Blackman, Amanda Haas, Karen Steger-May, Matthew J. Matava, Rick W. Wright and Robert H. Brophy
Erin Calaine Inglis, Danilo Iannetta, Louis Passfield and Juan M. Murias
Purpose: To (1) compare the power output (PO) for both the 20-minute functional threshold power (FTP20) field test and the calculated 95% (FTP95%) with PO at maximal lactate steady state (MLSS) and (2) evaluate the sensitivity of FTP95% and MLSS to training-induced changes. Methods: Eighteen participants (12 males: 37  y and 6 females: 28  y) performed a ramp-incremental cycling test to exhaustion, 2 to 3 constant-load MLSS trials, and an FTP20 test. A total of 10 participants returned to repeat the test series after 7 months of training. Results: The PO at FTP20 and FTP95% was greater than that at MLSS (P = .00), with the PO at MLSS representing 88.5% (4.8%) and 93.1% (5.1%) of FTP and FTP95%, respectively. MLSS was greater at POST compared with PRE training (12  W) (P = .002). No increase was observed in mean PO at FTP20 and FTP95% (P = .75). Conclusions: The results indicate that the PO at FTP95% is different to MLSS, and that changes in the PO at MLSS after training were not reflected by FTP95%. Even when using an adjusted percentage (ie, 88% rather than 95% of FTP20), the large variability in the data is such that it would not be advisable to use this as a representation of MLSS.
Rachel Vaccaro and Ted M. Butryn
Individuals suffering from mental illness face challenges that are related to stigma and lack of education that are often reinforced by the media. Specifically, the elite athletic culture is not conducive for athletes who suffer from mental illness because there is at times a belief that mental illnesses are less prevalent in elite sport. Even though incidence of mental illness in elite athletes has gained more prominence in the popular media, there is still a lack of research in this area. Specifically, there is limited research regarding media representations of athletes who suffer from mental illness. To address this gap in the literature, an ethnographic content analysis (ECA) was done to examine Suzy Favor Hamilton’s open discussion of bipolar disorder surrounding the release of her new memoir, Fast Girl: A Life Spent Running From Madness. ECA yielded one overarching theme with three supporting sub-themes. Results indicated that even though Favor Hamilton’s book worked to spread awareness, the media attention surrounding the book release represented omission of mental illness in the environment of athletics. Overall, sports culture provides an environment that is not often willing to accept that mental illnesses exist in athletes.
Niranjan Chakrabhavi and Varadhan SKM
A task involving an instructed finger movement causes involuntary movements in the noninstructed fingers of the hand, also known as finger interdependence. It is associated with both mechanical and neural mechanisms. The current experiment investigated the effect of finger interdependence due to systematic changes of the wrist posture, close to neutral. Eight right-handed healthy human participants performed submaximal cyclic flexion and extension at the metacarpophalangeal joint at 0° neutral, 30° extension, and 30° flexion wrist postures, respectively. The experiment comprised of an instruction to move one of the 4 fingers—index, middle, ring, and little. Movements of the instructed and noninstructed fingers were recorded. Finger interdependence was quantified using enslavement matrix, individuation index, and stationarity index, and it was compared across wrist postures. The authors found that the finger interdependence does not change with changes in wrist posture. Further analysis showed that individuation and stationarity indices were mostly equivalent across wrist postures, and their effects were much smaller than the average differences present among the fingers. The authors conclude that at wrist postures close to neutral, the finger interdependence is not affected by wrist posture.
Karen S. Meaney and Sonya L. Armstrong
Bullying in any context adversely affects individuals and organizations. Although bullying is typically conceived of as an issue specific to children in schoolyards, adult bullying is widespread, and the literature on workplace bullying continues to emerge as a scholarly focus. More specifically, academic bullying in higher-education institutions has been identified as an area of particular interest. Considerable literature exists that addresses definitions, characteristics, and effects of faculty bullying; however, the literature is scant regarding effective practice and policy that explicitly aim to prevent academic bullying. Furthermore, although this is a topic often discussed informally on university campuses, it does not appear to be addressed explicitly in formalized institutional policies. In this manuscript, the authors provide the findings of the initial stages of a content analysis aimed at exploring extant policy at public doctoral-granting universities. Implications and recommendations for policy development based on the results of this policy review are provided.
Yvonne G. Ellis, Dylan P. Cliff, Steven J. Howard and Anthony D. Okely
Purpose: To examine the acute effects of a reduced sitting day on executive function (EF) and musculoskeletal health in preschoolers. Methods: A sample of 29 children (54% boys; 4–5 y) participated in a randomized cross-over trial. Each child completed 2 protocols, which simulate a day at childcare in random order for 2.5 hours; a typical preschool day (50% sitting) and a reduced preschool day (25% sitting) where most sitting activities were replaced with standing activities. Sitting, standing, and stepping time were objectively assessed using an activPAL accelerometer. EF was evaluated using tablet-based EF assessments (inhibition, working memory, and task shifting). Musculoskeletal health was assessed using a handheld dynamometer and goniometer. Results: Compared with the typical preschool day, the reduced sitting day showed no significant differences for EF scores. Effect sizes for inhibition (d = 0.04), working memory (d = 0.02), and shifting (d = 0.11) were all small. For musculoskeletal health, no significant differences were reported after the reduced preschool day. The effect sizes for the hip extension force, hamstring flexibility, gastrocnemius length, and balancing on 1 leg were all small (d = 0.21, d = 0.25, d = 0.28, and d = 0.28). Conclusions: This study suggests that reducing sitting time is unlikely to result in acute changes in EF and musculoskeletal health among preschoolers.
Emma Weston, Matthew Nagy, Tiwaloluwa A. Ajibewa, Molly O’Sullivan, Shannon Block and Rebecca E. Hasson
Purpose: To compare the acute effects of intermittent physical activity (PA) across 4 different intensities on blood pressure. Methods: Thirty children (12 males and 18 females; aged 7–11 y; 33% overweight/obese; 53% nonwhite) completed 4 experimental conditions in random order: 8 hours sitting interrupted with 20, 2-minute low-, moderate-, high-intensity PA breaks, or sedentary screen-time breaks. PA intensity corresponded with 25%, 50%, and 75% of heart rate reserve. Blood pressure was measured during each condition in the morning (0800 h), noon (1200 h), and afternoon (1600 h). Results: There were no significant differences across conditions for systolic blood pressure (SBP; all Ps > .05). There was a significant effect of time with SBP decreasing throughout the day for all conditions (average morning SBP: 106  mm Hg, average noon SBP: 101  mm Hg, average afternoon SBP: 103  mm Hg; P = .01). There were no significant effects of condition or time on diastolic blood pressure (all Ps > .05). Conclusion: While sedentary behavior is known to be associated with hypertension in both adults and children, a single bout of prolonged sitting may be insufficient to produce hypertensive effects in otherwise healthy children. Future research should examine the appropriate dose of intermittent PA to accrue hypotensive responses in preadolescent children.
Sandro Venier, Jozo Grgic and Pavle Mikulic
Purpose: To explore the acute effects of caffeinated chewing gum on vertical-jump performance, isokinetic knee-extension/flexion strength and power, barbell velocity in resistance exercise, and whole-body power. Methods: Nineteen resistance-trained men consumed, in randomized counterbalanced order, either caffeinated chewing gum (300 mg of caffeine) or placebo and completed exercise testing that included squat jump; countermovement jump; isokinetic knee extension and knee flexion at angular velocities of 60 and 180°·s−1; bench-press exercise with loads corresponding to 50%, 75%, and 90% of 1-repetition maximum (1RM); and an “all-out” rowing-ergometer test. Results: Compared with placebo, caffeinated chewing gum enhanced (all Ps < .05) (1) vertical-jump height in the squat jump (effect size [ES] = 0.21; +3.7%) and countermovement jump (ES = 0.27; +4.6%); (2) knee-extension peak torque (ES = 0.21; +3.6%) and average power (ES = 0.25; +4.5%) at 60°·s−1 and knee-extension average power (ES = 0.30; +5.2%) at 180°·s−1, and knee-flexion peak torque at 60°·s−1 (ES = 0.22; +4.1%) and 180°·s−1 (ES = 0.31; +5.9%); (3) barbell velocity at 50% of 1RM (ES = 0.30; +3.2%), 75% of 1RM (ES = 0.44; +5.7%), and 90% of 1RM (ES = 0.43; +9.1%); and (4) whole-body peak power on the rowing-ergometer test (ES = 0.41; +5.0%). Average power of the knee flexors did not change at either angular velocity with caffeine consumption. Conclusions: Caffeinated chewing gum with a dose of caffeine of 300 mg consumed 10 min preexercise may acutely enhance vertical-jump height, isokinetic strength and power of the lower-body musculature, barbell velocity in the bench-press exercise with moderate to high loads, and whole-body power.
Derek T. Smith, Tannah Broman, Marcus Rucker, Cecile Sende and Sarah Banner
Effective academic advising in kinesiology is paramount to student success, contribution of the discipline to global health, and preparation of the workforce’s future leaders. Enrollment growth in kinesiology and its curricular breadth impose challenges that are unique from many other academic majors. The American Kinesiology Association convened a preworkshop titled “Advising in Kinesiology: Challenges and Opportunities” in January 2019 to begin dialogue related to advancing effective advising practices in kinesiology. Twenty-six attendees, all of whom were engaged in advising in different roles, participated in presentations and group discussions. This paper summarizes the preworkshop primary findings and offers some best-practice considerations. While it is clear that effective advising is positioned to advance the quality of kinesiology programs and our graduates, there is a dearth of supporting evidence, and addressing this through research is a needed priority.
Katie Weatherson, Lira Yun, Kelly Wunderlich, Eli Puterman and Guy Faulkner
Background: Ecological momentary assessment (EMA) is a method of collecting behavioral data in real time. The purpose of this study was to examine EMA compliance, identify factors predicting compliance, assess criterion validity of, and reactivity to, using EMA in a workplace intervention study. Methods: Forty-five adults (91.1% female, 39.7 [9.6] y) were recruited for a workplace standing desk intervention. Participants received 5 surveys each day for 5 workdays via smartphone application. EMA items assessed current position (sitting/standing/stepping). EMA responses were time matched to objectively measured time in each position before and after each prompt. Multilevel logistic regression models estimated factors influencing EMA response. Cohen kappa measured interrater agreement between EMA-reported and device-measured position. Reactivity was assessed by comparing objectively measured sitting/standing/stepping in the 15 minutes before and after each EMA prompt using multilevel repeated-measures models. Results: Participants answered 81.4% of EMA prompts. Differences in compliance differed by position. There was substantial agreement between EMA-reported and device-measured position (κ = .713; P < .001). Following the EMA prompt, participants sat 0.87 minutes more than before the prompt (P < .01). Conclusion: The use of EMA is a valid assessment of position when used in an intervention to reduce occupational sitting and did not appear to disrupt sitting in favor of the targeted outcome.