Correlation of King-Devick Test and Helmet Impact Exposures Over a Youth Football Season.

Background: The cumulative effect of repetitive subconcussive head impacts on neurocognitive function during youth contact sports remains largely unknown. There is a paucity of literature evaluating cumulative helmet forces over a season and their correlation with preseason and postseason cognitive performance tasks such as the King-Devick test (KDT).

Hypothesis: Higher helmet forces recorded throughout a 10-week, 10-game youth football season would correlate with slower performance on postseason KDT.

Self-reported foot strike patterns and sonographic evidence of Achilles tendinopathy in asymptomatic marathon runners.

It is unknown whether ultrasound findings and symptoms of Achilles tendinopathy in runners correlate with foot strike patterns. We aimed to examine the relationships among Achilles tendon ultrasound findings in runners with or without Achilles tendinopathy, their foot strike patterns, and their training regimens. We recruited marathon runners 18 years of age or older with no history of Achilles tendon pain or surgery participating in the 2018 DONNA Marathon.