Longitudinal morphological and performance profiles for American, NCAA Division I football players.

The aim of this study was to determine the changes in anthropomorphism and performance over a 4-year eligibility career of American football players. A total of 92 offensive and defensive linemen and 64 skill (wide receivers and defensive backs) player observations were included in the analysis. Data from preseason testing over a 7-year period were compiled, sorted, and analyzed by players' year in school. Assessments of strength included 1 repetition maximum bench press, squat, power clean, and a 225-lb maximum repetition muscle endurance test. Power and speed measures included vertical jump (VJ) and 40-yd (36.6-m) sprint. All strength measures improved significantly (p < 0.05) over the years of training. Skill players demonstrated a significant increase in power between years 1 and 2 but at no other time. Linemen did not demonstrate significant changes in VJ. Speed did not change significantly for either group over the 4 years of training. These data provide a theoretically predictable 4-year rate of change in anthropometric, strength, and power variables for Division I football players. By having a longitudinal assessment of expected physical improvement, it may be possible for strength training personnel to determine those who may need additional attention in an area to more closely improve as expected. Additionally, it is suggested that elite athletes may possess genetically superior attributes and therefore, when selecting athletes, particular attention should be paid to the selection of those who have previously demonstrated superior speed and power.