Objective measures of strain and subjective muscle soreness differ between positional groups and season phases in American collegiate football.

Purpose: To assess objective strain and subjective muscle soreness in ‘Bigs’ (Offensive and Defensive Line), ‘Combos’ (Tight Ends, Quarterbacks, Line and Running-Backs) and ‘Skills’ (Wide Receivers and Defensive Backs) American College Football (ACF) players during off-season, fall-camp and in-season phases. Methods: Twenty-three male players were assessed once weekly (3-week off-season, 4-week fall-camp, 3-week in-season) for hydroperoxides (FORT), antioxidant capacity (FORD) and oxidative stress index (OSI)), countermovement jump flight-time, reactive strength index modified (RSImod), and subjective soreness. Linear mixed-models analysed the effect of a two within-subject standard deviation change between predictor and dependent variables. Results: Compared to fall-camp and in-season phases, off-season FORT (P=<.001 and <.001), FORD (P=<.001 and <.001), OSI (P=<.001 and <.001), Flight-time (P=<.001 and <.001), RSImod (P=<.001 and <.001) and soreness (P=<.001 and <.001) were higher for ‘Bigs’, whilst FORT (P=<.001 and <.001) and OSI (P=.02 and <.001) were lower for ‘Combos’. FORT was higher for ‘Bigs’ compared to ‘Combos’ in all phases (P=<.001, .02 and .01). FORD was higher for ‘Skills’ compared to ‘Bigs’ in off-season (P=.02) and ‘Combos’ in-season (P=.01). OSI was higher for ‘Bigs’ compared to ‘Combos’ (P=<.001) and ‘Skills’ (P=.01) during off-season and to ‘Combos’ in-season (P=<.001). Flight-time was higher for ‘Skills’ in fall-camp compared to ‘Bigs’ (P=.04) and to ‘Combos’ in-season (P=.01). RSImod was higher for ‘Skills’ during off-season compared to ‘Bigs’ (P=.02) and ‘Combos’ during fall-camp (P=.03), and in-season (P=.03). Conclusion: Off-season ACF training resulted in higher objective strain and subjective muscle soreness in ‘Bigs’ compared to fall-camp and during in-season compared to ‘Combos’ and ‘Skills’ players.