Innate immune responses to a single session of sprint interval training

Abstract

Sprint Interval Training (SIT) is a potent stimulus for physiological and metabolic adaptations comparable with those induced by traditional 'aerobic' endurance training. There has been a great deal of recent research on SIT, which may lead to increased use of this type of training. The purpose of the present study was to determine the acute effects of SIT on aspects of innate immunity not previously researched in this context. Nine males completed one SIT and one resting control trial in a crossover design. Blood and saliva samples were obtained at pre-, post-and 30 minutes post-exercise to measure blood neutrophil oxidative burst activity (OBA) in addition to saliva secretary IgA (s-IgA) and lysozyme. SIT induced a significant depression of neutrophil fMLP-stimulated OBA (-30% 30 minutes post-exercise, P < 0.01), PMA-stimulated OBA (-14% post-exercise, -21% 30 minutes post-exercise, P < 0.01) and bacterial-stimulated degranulation (-23% post-exercise, -32% 30 minutes postexercise, P < 0.01) but not fMLP-then-PMA-stimulated OBA, saliva lysozyme or s-IgA concentrations or secretion rates (P > 0.05). The main novel finding of the present study is that a single session of SIT causes significant exercise-induced immunodepression of some neutrophil functions but mucosal immunity was not depressed.

Exercise, But Not Acute Sleep Loss, Increases Salivary Antimicrobial Protein Secretion

“…Although the small sample size is a potential limitation, the same number of participants were used in another study detailing the effect of exercise and sleep loss on mucosal parameters (11 participants were enrolled but only 8 were used for the salivary analyses) (7). In addition, most studies performed in this field use between 8 and 12 participants (1,6,8,9,10). Larger studies outside the field of exercise science have been conducted.…”

Exercise, Immunity, and Illness

“…Evidence from animal studies suggests that increased mobilization of pIgR occurs only above a certain threshold of increased sympathetic stimulation (Proctor et al, 2003). This may explain why a brief bout of high-intensity exercise leads to increases in salivary SIgA (e.g., Davison, 2011). However, this does not explain the decrease found with prolonged exercise bouts ).…”

Nutritional and Physical Activity Interventions to Improve Immunity

“…Despite such effects on mucosal immunity not being replicated in a more recent study with active males, decreases in neutrophil functional capacity (degranulation and oxidative burst) were observed following such activity. 71 However, a more 'traditional' interval training session (20 efforts at 100% VO 2max with 2-minutes recovery intervals at 30%, similar to the type of session that is common for many endurance athletes) was previously shown to have little effect on salivary SIgA. The majority of these studies have also not measured URTI incidence and/or have lacked power to determine change in incidence with interval type exertion.…”