Solid Ground
When tested in the unfatigued condition, the sway path lengths while standing on solid ground decreased on average for BALANCE (−9.9%) and BALANCE-HIIT (−12.4%) but not for HIIT-BALANCE (+3.3%). Less pronounced average effects were observed in the fatigued testing condition with reductions for BALANCE (−2.7%) and BALANCE-HIIT (−3.0%) but increased sway path lengths for HIIT-BALANCE (+9.0%). The group*time interaction showed moderate differences for BALANCE vs. HIIT-BALANCE and for BALANCE-HIIT vs. HIIT-BALANCE in the unfatigued testing condition—because of the confidence intervals of the effect sizes, the data are also compatible with negligible to large effects (Figure 