The purpose of this investigation was to examine countermovement jump differences between positional groups in American football.
Methods
85 Division I collegiate football players were assigned to one of three groups (lineman = 32, midskill = 29, skill = 24). Each participant performed three CMJ trials using a portable force platform. A one-way analysis of variance was performed on all variables of interest. An a priori significance level of p < 0.05 was used for all analysis.
Results
Significant differences were present across all three groups for jump height (p < 0.01) and RSImod (p < 0.001) with the skill group having the highest values and the linemen having the lowest. Inversely, take-off momentum and body mass were the greatest in the linemen group with the lowest being the skill group (p < 0.001). Linemen had longer duration in the propulsive phase (p < 0.01), braking phase (p < 0.01), and time to take off (p < 0.01).
Conclusions
The differences between groups can aid in the design of training programs targeting specific traits for each positional group. Additionally, differences in positional metrics of interest may exist when using the CMJ to monitor fatigue status over the course of a competitive season.
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