Mouthpiece Use Reduces Post Exercise Serum Cortisol Levels

Abstract

Recent work has shown that a lower jaw mouthpiece (MP) can decrease lactate, improve airway dynamics and decrease salivary cortisol following exercise. This study aimed to determine if wearing a lower jaw MP (ArmourBite Technology) altered serum cortisol in 13 collegiate‐aged males during or after physical work. At least 7 days following one repetition maximum (1RM) testing, subjects completed 2 trials, separated by 7 days, of 6 sets x 10 repetitions of back squats with 2 min rest between sets. Load was set at 80% of each subject's 1RM and resistance was adjusted during testing so subjects completed 10 repetitions during each set. Treatment order was randomized and blood was sampled: pre exercise, after 3 sets (mid), post exercise, 30, 60 and 120 min post exercise. Each sample was labeled and frozen for determination of cortisol (ìg/dL) via ELISA (ALPCO Diagnostics, Salem, NH). There was no difference in pre exercise cortisol between groups (MP: 21.55±9.82 vs 25.58±10.88). The MP group had lower (P<.05) cortisol levels at mid (MP: 19.39±6.90 vs 27.84±14.55) and post 30 (MP: 22.91±8.47 vs 31.81±10.79), while no differences existed immediately post exercise, post 60, or post 120. These results confirm in serum that the use of lower jaw MPs attenuates the cortisol response following strenuous physical exercise. This suggests that the use of a MP may aid in post exercise recovery and may diminish the stress of physical exercise.