Key points are not available for this paper at this time.
The purpose of this study was to determine the performance and hormonal responses to a 15-week off-season training program for American football. Nine skill position players from a National Collegiate Athletic Association (NCAA) Division I-A football team participated as subjects in this study. Following 4 weeks of weight training (phase I), subjects performed weight training concurrently with high-volume conditioning drills (phase II). Phase III consisted of 15 spring football practice sessions executed over a 30-day period. Performance and hormonal changes were assessed prior to phase I, and following phases I, II, and III. Maximal strength was significantly increased (p > 0.05) for all strength tests during phase I. Squat and power clean values decreased following phase II (p > 0.05), with all values returning to baseline upon completion of phase III. Sprinting speed significantly worsened during phase I (p > 0.05), but then returned to baseline during phase III. Vertical jump and agility improved during phase I (p > 0.05), with vertical jump remaining unchanged for the duration of the study and agility returning to baseline following phase II. Testosterone levels decreased during phase II (p > 0.05) prior to returning to baseline levels during phase III. Cortisol and the testosterone/cortisol ratio remained unchanged during the course of the investigation. Even though overtraining did not occur in the current investigation, a significant maladaptation in performance did occur subsequent to phase II. For this particular athletic population, a strength and conditioning program utilizing a reduced training volume-load may prove more effective for improving performance in the future.
Moore et al. (2007) studied this question.