Do whole-body vibration exercise and resistance exercise modify concentrations of salivary cortisol and immunoglobulin A?

A single bout of resistance exercise (RE) induces hormonal and immune responses, playing an important role in a long-term adaptive process. Whole-body vibration (WBV) has also been shown to affect hormonal responses. Evidence suggests that combining WBV with RE may amplify hormonal and immune responses due to the increased neuromuscular load. Therefore, the aim of this study was to evaluate salivary cortisol (Scortisol) and salivary IgA (SIgA) concentrations following a RE session combined or not with WBV. Nine university students (22.9 +/- 5.1 years, 175.8 +/- 5.2 cm, and 69.2 +/- 7.3 kg) performed five sets of squat exercise (70% one-repetition-maximum) combined (R+V30) or not (R) with WBV at 30 Hz. Saliva samples were obtained before and after exercise. Subjects also rated their effort according to the Borg CR-10 scale (RPE). Data were analyzed by a mixed model. RPE was higher after R+V30 (8.3 +/- 0.7) compared to R (6.2 +/- 0.7). However, Scortisol (pre: 10.6 +/- 7.6 and 11.7 +/- 7.6, post: 8.3 +/- 6.3 and 10.2 +/- 7.2 ng/mL for R and R+V30, respectively) and SIgA concentrations (pre: 98.3 +/- 22.6 and 116.1 +/- 51.2, post: 116.6 +/- 64.7 and 143.6 +/- 80.5 mu g/mL for R and R+V30, respectively) were unaffected. No significant correlations were observed between Scortisol and RPE (r = 0.45, P = 0.22; r = 0.30, P = 0.42, for R and R+V30, respectively). On the basis of these data, neither protocol modified salivary cortisol or IgA, although RPE was higher after R+V30 than R.