Fig. 4

Peripheral blood CD56^dim NK cell concentrations (cells/µL) across 18 timepoints in all participants pooled (N = 18) (A) and then stratified by age (old, N = 9 vs. young, N = 9) for peak CD56^dim NK cell concentrations (B) total area under the curve (cells/µL x minutes) (C) average CD56^dim NK cell concentration (D) and CD56^dim NK dose (cells per kilogram of body mass) (E) in REST (grey circles and bars), MIIE (blue circles and bars) and HIIE (red circles and bars). Values are mean ± SD. * indicates significant differences between trials: *p < 0.05. # indicates a significant difference between old MIIE vs old HIIE, p < 0.05. Pairwise comparisons are not included on panel A