Association of Y Balance Test Reach Asymmetry and Injury in Division I Athletes
Neuromuscular control has been proposed as a possible modifiable injury risk factor in athletes. Several screening tools currently exist, yet no consensus exists as to their use in preparticipation screening of athletes. Factors such as the time required, availability of equipment, and specificity to certain populations and pathologies are cited as barriers to use. Thus, a single, easily administered test that could be used across genders and with multiple sports would assist in preventing injury without overburdening the staff responsible for the testing.
The Y Balance Test (YBT) is an instrumented screening tool that assesses dynamic balance by having the subject balance on one leg while the contralateral leg reaches in anterior (ANT), posteromedial (PM) and posterolateral (PL) directions. The YBT was developed to improve reliability of the modified Star Excursion Balance Test that also checks three directions and was derived from the original Star Excursion Balance Test that tested eight reach directions.
The YBT has been proposed to screen for injury risk, yet little data currently exist on this association. In the January 2015 edition of Medicine & Science in Sports & Exercise®, this study examined the association between YBT results and noncontact in-season injury in a sample of 184 Division I college athletes from multiple sports (2). The authors utilized the YBT to screen athletes during their preparticipation examination to determine asymmetry, defined as the absolute difference between legs in ANT, PM, and PL directions, as well as a composite score (CS), defined as the summed average of right/left ANT, PM, and PL normalized to leg length. Noncontact injuries that required athletic training staff intervention during an athlete’s season were recorded for the purposes of this study. The authors hypothesized that asymmetrical reach distance in the anterior direction would be related to increased odds of injury. They also hypothesized that a lower YBT CS would be associated with higher odds of noncontact in-season injury in this sample group.
Receiver operating characteristic curves were calculated to determine the optimal cut-points for predicting injury based on both asymmetry and CS. Of the 184 athletes in this study, 81 sustained a noncontact injury. The receiver operating characteristic curves determined asymmetry >4 cm as the optimal cut-point for predicting injury. This study was unable to determine an optimal cut-point to predict injury that maximized sensitivity and specificity for CS, so further analysis was completed with CS as a continuous variable. Only the ANT asymmetry was associated significantly with noncontact injury, while CS in this sample did not demonstrate an association. This suggests that imbalance with anterior reach during single-leg stance identified those at elevated risk for injury across multiple sports in a season. The authors acknowledged that further research needs to be conducted to determine how to best use this tool to predict injury risk.
YBT ANT asymmetry greater than 4 cm was associated with increased risk of noncontact injury across multiple sports in a season.
Aerobic Exercise and Attention Deficit Hyperactivity Disorder: Brain Research
In the January 2015 edition of Medicine & Science in Sports & Exercise®, authors hypothesized that aerobic exercise could be used as an effective adjunctive therapy for enhancing the effects of methylphenidate on the clinical symptoms, cognitive function, and brain activity of adolescents with attention deficit hyperactivity disorder (ADHD) (1).
The study was composed of 35 adolescents with ADHD who were randomly assigned to one of two groups in a 1/1 ratio. The groups were as follows: methylphenidate treatment + 6 wk exercise (Sports-ADHD) or methylphenidate treatment + 6 wk education (Edu-ADHD).
Symptoms of ADHD, cognitive function, and brain activity were evaluated at baseline and after 6 wk of treatment using DuPaul’s ADHD rating scale (K-ARS), the Wisconsin card sorting test, and 3-T functional magnetic resonance imaging, respectively.
The results demonstrated that the K-ARS total score and perseverative errors in the Sports-ADHD group decreased, compared to the Edu-ADHD group. After the 6-wk treatment period, the mean B value of the right frontal lobe increased in the Sports-ADHD group compared to the Edu-ADHD group. The mean B value in the temporal lobe decreased in the Sports-ADHD group, while it did not change in the Edu-ADHD group. There was a negative correlation between the change in the right prefrontal cortex and the change in K-ARS and perseverative errors in all adolescents with ADHD.
Results of this study indicate that aerobic exercise was able to increase the effectiveness of methylphenidate on clinical symptoms, perseverative errors, and brain activity within the right frontal and temporal cortices in response to Wisconsin card sorting test stimulation in adolescents with ADHD.
1. Choi JW, Han DH, Kang KD, et al. Aerobic exercise and attention deficit hyperactivity disorder: brain research. Med Sci. Sports Exerc. 2015; 47: 33–39.
2. Smith CA, Chimera NJ, Warren M. Association of Y Balance Test reach asymmetry and injury in division I athletes. Med. Sci. Sports Exerc. 2015; 47: 136–141.