Patellar tendinopathy is often managed with a patellar tendon strap, however, their effectiveness is unsubstantiated. The purpose of this study was to determine if straps altered pain or lower extremity kinetics of individuals with patellar tendinopathy during landing. Thirty participants with patellar tendinopathy and 30 controls completed drop jumps with and without patellar tendon straps. Wearing the strap, tendinopathy participants demonstrated significantly decreased pain and reduced knee adductor moment; all participants displayed significantly decreased anterior ground reaction force while wearing a strap. Patellar tendon strapping may reduce pain due to alterations in direction and magnitude of loading.
Adam B. Rosen, Jupil Ko, Kathy J. Simpson and Cathleen N. Brown
Jeffrey D. Simpson, Ethan M. Stewart, Anastasia M. Mosby, David M. Macias, Harish Chander and Adam C. Knight
Context: Lateral ankle sprains are a common injury in which the mechanics of injury have been extensively studied. However, the anticipatory mechanisms to ankle inversion perturbations are not well understood. Objective: To examine lower-extremity kinematics, including spatial and temporal variables of maximum inversion displacement and maximum inversion velocity, during landings on a tilted surface using a new experimental protocol to replicate a lateral ankle sprain. Setting: Three-dimensional motion analysis laboratory. Participants: A total of 23 healthy adults. Interventions: Participants completed unexpected (UE) and expected (EXP) unilateral landings onto a tilted surface rotated 25° in the frontal plane from a height of 30 cm. Main Outcome Measures: Ankle, knee, and hip kinematics at each discrete time point from 150 ms pre-initial contact (IC) to 150 ms post-IC, in addition to maximum ankle inversion and maximum inversion velocity, were compared between UE and EXP landings. Results: The UE landing produced significantly greater maximum inversion displacement (P < .01) and maximum inversion velocity (P = .02) than the EXP landing. Significantly less ankle inversion and internal rotation were found during pre-IC, whereas during post-IC, significantly greater ankle inversion, ankle internal rotation, knee flexion, and knee abduction were observed for the UE landing (P < .05). In addition, significantly less hip flexion and hip adduction were observed for the UE landing during pre-IC and post-IC (P < .05). Conclusions: Differences in the UE and EXP landings indicate the experimental protocol presented a UE inversion perturbation that approximates the mechanism of a lateral ankle sprain. Furthermore, knowledge of the inversion perturbation elicited a hip-dominant strategy, which may be utilized to assist with ankle joint stabilization during landing to further protect the lateral ankle from injury.
Jeffrey D. Simpson, Ludmila Cosio-Lima, Eric M. Scudamore, Eric K. O’Neal, Ethan M. Stewart, Brandon L. Miller, Harish Chander and Adam C. Knight
Purpose: Wearing a weighted vest (WV) during daily living and training can enhance jump and sprint performance; however, studies examining the efficacy of this method in female populations is limited. This study examined the effect of wearing a WV during daily living and training on countermovement jump (CMJ), change-of-direction, and sprint performance. Methods: Trained females were separated into intervention (n = 9) and control (n = 10) groups. The intervention group wore WVs of ∼8% body mass 4 days per week for 8 hours per day (32 h/wk total), and 3 training sessions per week for the first 3 weeks. Subsequently, 3 weeks of regular training without WV stimulus was completed. The control group received no intervention and continued normal training for 6 weeks. Average and best performance was assessed on the single CMJ, four continuous CMJ, t-test change-of-direction drill, and a 25-m sprint at baseline, week 3, and week 6. Results: No significant interactions or group effects were found. However, significant time main effects revealed increases in average rate of force development during the CMJ from baseline to week 3 (P = .048) and week 6 (P = .013), whereas peak vertical ground reaction force increased during the four continuous CMJ from baseline to week 3 (P = .048) and week 6 (P = .025) for both groups. Conclusions: The lower relative WV load used in this study failed to elicit significant improvements in jump and sprint performance in comparison with routine training, or that which have been found in past investigations with elite male athletes completing high-intensity performance tasks with greater WV loads.
Lindsey E. Eberman, Kimberly J. Bodey, Rebecca Zakrajsek, Madeline McGuire and Adam Simpson
The National Standards for Sport Coaches (2006) acknowledges that differences exist in athletes’ ability to tolerate heat. As such, Domain 2: Safety and Injury Prevention (S7-10), Domain 3: Physical Conditioning (S12-13), and Domain 7: Organization and Administration (S34) list expectations for coaches’ ability to recognize and respond to heat illness. However, only the American Red Cross of Greater Indianapolis (Domain 2 specific) and 13 programs are accredited by NCACE. Moreover, on-line trainings frequently used to educate novice interscholastic and recreational sport coaches provide only a cursory review of heat illness precautions, symptoms, and remedies.
The purpose of this exploratory study is to identify changes in coaches’ actual and perceived knowledge after an on-line educational intervention, as well as determine whether the educational intervention will decrease the knowledge gap.
A pre-test/post-test design was used to identify the effect of an educational intervention on perceived and actual knowledge of sport coaches.
Coaches (n=19; male=14, female=5) were solicited via email made available by the Indiana High School Athletic Association and the Indiana Youth Soccer Association – Olympic Development Program.
The Perceived Knowledge Questionnaire (five-item survey) and an actual knowledge assessment (two versions of 19-item quiz) were used to measure the coaches’ perceived and actual knowledge about the prevention, recognition, and treatment of exertional heat illnesses. Participants completed the “Beat the Heat: Be a Better Coach in Extreme Environmental Conditions” educational intervention.
Coaches completed the on-line educational module including pre-test and post-tests evaluations of actual and perceived knowledge.
Researchers performed three separate paired t-tests to identify the effect of the educational intervention on the dependent variables: actual knowledge, perceived knowledge, and knowledge gap. Significance was set a-prior at p<0.05.
Participants demonstrated a significant 18.1% improvement (t18=-4.877, p<0.001, ES=0.62) in actual knowledge scores. Perceived knowledge also significantly improved (t18=-2.585, p=0.019, ES=0.25). Knowledge gap, the difference between actual knowledge and perceived knowledge, became significantly smaller (t18=4.850, p<0.001, ES=0.63).
Results indicate the on-line educational intervention improved actual knowledge, perceived knowledge, and decreased the knowledge gap. Additional large scale study of this intervention is warranted.