Background: Symptom scales are routinely used in sport during concussion screening and return-to-play. Limited research has explored the presence of concussion symptoms in the absence of a diagnosed concussion. This study analyzed concussion symptom scores in concussed vs. non-concussed football players after football activities and evaluated the effect of field of play variables. Methods: NCAA Division I football players with (n = 9) and without (n = 30) diagnosed concussion completed concussion symptom scales (C3 Logix) following practice for 1 week. Wet bulb globe temperature (WBGT), play duration, equipment, and location (inside/outside) were recorded. Mixed models analyzed the effect of day, WBGT, equipment, location, and play duration on concussion-like symptoms in non-concussed players and determined the time course of symptom relief in concussed players. Results: Fatigue or low energy (27.6%), neck pain (16.8%), feeling slowed down (14.8%), and headache (12.8%) were most reported. In non-concussed players, total symptoms scores were higher early in the week (Monday/Tuesday) and decreased throughout the week (p < 0.01). No effect of play duration (p = 0.49), WBGT (p = 0.12), equipment (p = 0.40), or location (p = 0.83) was found. Symptom scores were greater in the concussed vs. non-concussed groups on days 1–3. Conclusions: Football players report concussion-like symptoms in the absence of a concussion diagnosis, particularly following the first few practices after a game.
Matthews et al. (2026) studied this question.