Research Paper Volume 15, Issue 3 pp 765—776

Figure 2. p16^INK4a mRNA in human skeletal muscle 24 h after SSE and HIIE. The cellular senescence marker p16^INK4a mRNA decreased 24 h after HIIE (d = 0.90, p = 0.04), whilst no change was observed after SSE at similar amount of cycling work (A). Individual responses in p16^INK4a mRNA to SSE and HIIE are shown in (B and C), respectively. p16^INK4a-expressing cells (representing all replicable cells) were located outsides myofibers, indicated by an arrow to brown precipitates (D). p16^INK4a-expression cells (replicable cells) increased immediately after HIIE and returned to baseline in 24 h (E). Individual responses to SSE and HIIE are shown in (F and G), respectively. ^*Significant difference against pre-exercise baseline, p < 0.05. ^†Significance against SSE, p < 0.05. Abbreviations: SSE: steady state cycling exercise (60% maximal aerobic power); HIIE: high intensity interval cycling exercise (120% maximal aerobic power).