Research Paper Volume 15, Issue 3 pp 765—776

Figure 4. γ-H2AX⁺ myofibers in human skeletal muscle after SSE and HIIE. A representative muscle cross-section of immunohistochemical stain indicates brown γ-H2AX signals concentrated near periphery of myofibers (A). γ-H2AX⁺ myofibers elevated immediately only after HIIE (not SSE) and returned to baseline in 24 h (B). Individual responses to SSE and HIIE are shown in (C and D), respectively. H2AX mRNA was not influenced by exercise (E). ^*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).