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Published on: February 19, 2017
Helmetless Tackling Training Intervention and Preseason Self-efficacy Effects on Head Impacts in Hawai'i High School
Ivet Lloansi Rodriguez1, Bret Freemyer1, Kumiko Hashida2
1Department of Kinesiology and Rehabilitation Science, University of Hawai'i at Mānoa, Honolulu, HI.
Objective:
To determine how football head impacts are influenced by self-efficacy (SE), helmetless tackling intervention participation (IP), and years of experience (YE) playing football.
Design:
Cross-sectional.
Setting:
Three high schools.
Participants:
120 (male; n = 118, female; n = 2, 15.57 ± 1.23 years) participants were recruited from 5 high school teams (3 varsity and 2 junior-varsity).
Independent Variables:
SE, days of IP, and YE playing tackle football.
Main Outcome Measures:
SE was measured using a 53-question survey and categorized into 5 subscales. The accumulation of total head impacts (THI) was measured using Riddell InSite Speedflex helmets (Elyria, OH) throughout the season. Head impact exposure (HIE) was standardized as a ratio of impacts per session (games, scrimmages, and practices). Multiple regression analyses tested the relationship between THI or HIE with the predictor variables.
Results:
For THI, 22.1% was explained by the predictors (r = 0.470, r 2 = 0.221). Intervention participation had a negative correlation (B = -4.480, P = 0.019), whereas confidence in performing proper tackling and blocking (SE1) (B = 3.133, P = 0.010) and >8 YE (B = 135.9, P = 0.009) positively correlated with THI. For HIE, 25.4% was explained by the predictors (r = 0.504, r 2 = 0.254). Intervention participation negatively correlated (B = -0.077, P = 0.007), whereas SE1 (B = 3.133, P = 0.010) and >8 YE (B = 2.735, P ≤ 0.001) correlated positively with HIE.
Conclusions:
Increased head impacts were associated with less helmetless tackling participation, more than 8 YE, and more self-confidence in tackling ability. Increasing the amount of time athletes spend practicing proper tackling and blocking techniques to reduce head first and risky play is warranted to reduce the amount of head impacts received over time.
