***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: We assessed the effectiveness of two generalized visual training programmes in enhancing visual and motor performance for racquet sports . Forty young participants were assigned equally to groups undertaking visual training using Revien and Gabor ’s Sports Vision programme ( Group 1 ) , visual training using Revien ’s Eyerobics ( Group 2 ) , a placebo condition involving reading ( Group 3 ) and a control condition involving physical practice only ( Group 4 ) . Measures of basic visual function and of sport-specific motor performance were obtained from all participants before and immediately after a 4-week training period . Significant pre- to post-training differences were evident on some of the measures ; however , these were not group-dependent . Contrary to the cl aims made by proponents of generalized visual training , we found no evidence that the visual training programmes led to improvements in either vision or motor performance above and beyond those result ing simply from test familiarity Objective : To compare the odds of sustaining moderate and severe head impacts , rather than mild , between high school football players with high and low visual performance . Design : Prospect i ve quasi-experimental . Setting : Clinical Research Center/On-field . Participants : Thirty-seven high school varsity football players . Interventions : Athletes completed the Nike SPARQ Sensory Station visual assessment before the season . Head impact biomechanics were captured at all practice s and games using the Head Impact Telemetry System . Main Outcome Measures : Each player was classified as either a high or low performer using a median split for each of the following visual performance measures : visual clarity , contrast sensitivity , depth perception , near – far quickness , target capture , perception span , eye – h and coordination , go/no go , and reaction time . We computed the odds of sustaining moderate and severe head impacts against the reference odds of sustaining mild head impacts across groups of high and low performers for each of the visual performance measures . Results : Players with better near – far quickness had increased odds of sustaining moderate [ odds ratios ( ORs ) , 1.27 ; 95 % confidence intervals ( CIs ) , 1.04 - 1.56 ] and severe head impacts ( OR , 1.45 ; 95 % CI , 1.05 - 2.01 ) as measured by Head Impact Technology severity profile . High and low performers were at equal odds on all other measures . Conclusions : Better visual performance did not reduce the odds of sustaining higher magnitude head impacts . Visual performance may play less of a role than expected for protecting against higher magnitude head impacts among high school football players . Further research is needed to determine whether visual performance influences concussion risk . Clinical Relevance : Based on our results , we do not recommend using visual training programs at the high school level for the purpose of reducing the odds of sustaining higher magnitude head impacts The purpose of this experiment was to determine the effect of type and magnitude of retinal defocus on golf putting accuracy , and on the related eye , head , and putter movements . Eye , head , and putter movements were assessed objective ly along with putting accuracy in 16 young adult , visually normal inexperienced golfers during a fixed 9-foot golf putt .  Convex spherical ( + 0.50 D , + 1.00 D , + 1.50 D , + 2.00 D , + 10.00 D ) and cylindrical ( + 1.00 D x 90 , + 2.00 D x 90 ) lenses were added binocularly to create various types and magnitudes of retinal defocus . Putting accuracy was significantly reduced only under the highest spherical blur lens condition ( + 10.00 D ) . No significant differences were found between any other lens conditions for eye , head or putter movements . Small amounts of spherical and astigmatic retinal defocus had a minimal impact on overall golf putting performance , except for putting accuracy under the highest blur condition . This is consistent with the findings of related studies . For a fixed putting distance , factors other than quality of the retinal image , such as blur adaptation and motor learning , appeared to be sufficient to maintain a high level of motor performance Background . The cl aim that sports vision training programs can enhance visual skills and the level of sporting performance was investigated . Methods . Thirty young subjects were assigned equally to visual training , reading ( placebo ) , and control groups .  Visual and motor tests were administered before and after 4 weeks of training or control activity to determine whether any improvements in performance had occurred . Results . Significant improvements on some aspects of vision were apparent for the visual training group , but their improvements in both vision and motor performance were no greater than for either of the other groups . Discussion . There was no evidence for visual training improving either visual or motor performance beyond levels due simply to test familiarity . The benefits of the visual training exercises commonly used by optometrists to enhance sports performance are therefore open to question BACKGROUND Athletes have demonstrated better visual abilities than nonathletes . A vision assessment for an athlete should include methods to evaluate the quality of visual performance skills in the most appropriate , accurate , and repeatable manner . This study determines the reliability of the visual performance measures assessed with a computer-based system , known as the Nike Sensory Station . METHODS One hundred twenty-five subjects ( 56 men , 69 women ) , age 18 to 30 , completed Phase I of the study . Subjects attended 2 sessions , separated by at least 1 week , in which identical protocol s were followed . Subjects completed the following assessment s : Visual Clarity , Contrast Sensitivity , Depth Perception , Near-Far Quickness , Target Capture , Perception Span , Eye-H and Coordination , Go/No Go , and Reaction Time .  An additional 36 subjects ( 20 men , 16 women ) , age 22 to 35 , completed Phase II of the study involving modifications to the equipment , instructions , and protocol s from Phase I. RESULTS Results show no significant change in performance over time on assessment s of Visual Clarity , Contrast Sensitivity , Depth Perception , Target Capture , Perception Span , and Reaction Time . Performance did improve over time for Near-Far Quickness , Eye-H and Coordination , and Go/No Go . CONCLUSIONS The results of this study show that many of the Nike Sensory Station assessment s show repeatability and no learning effect over time . The measures that did improve across sessions show an expected learning effect caused by the motor response characteristics being measured 
    Output:
    
Good reliability was observed in PR , PRL , and PRR .
These results indicate that PP can be applied to asses PV abilities in sports .