The maximal oxygen uptake (VO_2max) prediction models established by step tests are often used for evaluating cardiorespiratory fitness (CRF). However, it is unclear which type of stepping frequency sequence is more suitable for the public to assess the CRF. Therefore, the main purpose of this study was to test the effectiveness of two 3-min incremental step-in-place (3MISP) tests (i.e., 3MISP_30s and 3MISP_60s) with the same total number of steps but different step-frequency sequences in predicting VO_2max. In this cross-sectional study, a total of 200 healthy adults in Taiwan completed 3MISP_30s and 3MISP_60s tests, as well as cardiopulmonary exercise testing. The 3MISP_30s and 3MISP_60s models were established through multiple stepwise regression analysis by gender, age, percent body fat, and 3MISP-heart rate. The statistical analysis included Pearson’s correlations, the standard errors of estimate, the predicted residual error sum of squares, and the Bland–Altman plot to compare the measured VO_2max values and those estimated. The results of the study showed that the exercise intensity of the 3MISP_30s test was higher than that of the 3MISP_60s test (% heart rate reserve (HRR) during 3MISP_30s vs. %HRR during 3MISP_60s = 81.00% vs. 76.81%, p < 0.001). Both the 3MISP_30s model and the 3MISP_60s model explained 64.4% of VO_2max, and the standard errors of the estimates were 4.2043 and 4.2090 mL·kg⁻¹·min⁻¹, respectively. The cross-validation results also indicated that the measured VO_2max values and those predicted by the 3MISP_30s and 3MISP_60s models were highly correlated (3MISP_30s model: r = 0.804, 3MISP_60s model: r = 0.807, both p < 0.001). There was no significant difference between the measured VO_2max values and those predicted by the 3MISP_30s and 3MISP_60s models in the testing group (p > 0.05). The results of the study showed that when the 3MISP_60s test was used, the exercise intensity was significantly reduced, but the predictive effectiveness of VO_2max did not change. We concluded that the 3MISP_60s test was physiologically less stressful than the 3MISP_30s test, and it could be a better choice for CRF evaluation.

Effects of calf and ankle tissue flossing on countermovement jump (CMJ) braking strategy and local passive mechanical properties were examined after repeated jumping. Forty healthy male college students matched by CMJ height were randomized within pairs to the flossing group (FLOSS; n = 20) or control group (CON; n = 20). After 100 jumps from a 30 cm box, FLOSS received calf and ankle flossing, whereas CON performed identical ankle movements without flossing. CMJ braking-phase variables, CMJ and squat jump (SJ) performance, and lower-leg muscle–tendon properties (MyotonPRO) were assessed at baseline (T₁), immediately postexercise (T₂), and postintervention (T₃). After Holm adjustment, significant group-by-time interactions occurred for braking phase duration (p = 0.015, ${\eta }_p^2$ = 0.128) and braking rate of force development (RFD) (p = 0.012, ${\eta }_p^2$ = 0.145), but not jump height or passive mechanical properties. From T₂ to T₃, FLOSS showed a greater decrease in braking phase duration and a greater increase in braking RFD than CON, with similar braking net impulse. However, these differences were not confirmed by ANCOVA adjusting for T₂ values. These findings suggest a possible acute modification of CMJ braking strategy rather than improved jump performance or recovery. Integrating force–time, jump, and muscle mechanical measures may allow for more comprehensive monitoring of acute flossing responses.