Author(s): TRISKA, C., POWOLNY, V., Institution: LEISTUNGSSPORT AUSTRIA, Country: AUSTRIA, Abstract-ID: 536

INTRODUCTION:
A persistent issue in critical power (CP) and W´ research is the variability in methodologies across studies. Some research groups employ the traditional approach, which involves multiple exhaustive trials of differing durations to determine CP and W´. Others question the validity of this method and advocate the 3-min all-out test (3AOT) as a potentially more accurate alternative. The traditional approach relies on the relationship of power vs. duration and mathematical modelling to determine CP and W´. In contrast, the 3AOT is designed to deplete W´ within the first 2.5 minutes, thereby establishing a plateau that represents CP within the last 30 s of the test. At present, there is equivocal evidence regarding whether these two approaches can be used interchangeably. Therefore, the aim of this meta-analysis was to examine potential differences between the traditional method and the 3AOT.
METHODS:
A systematic search of the PubMed database using the terms “all-out AND ‘critical power’” identified 147 studies. Inclusion criteria were: (1) participants were healthy, over 18 years of age, and included both trained and untrained individuals; (2) studies employed the traditional determination of CP and W´ using time-to-exhaustion (TTE) or time-trial (TT) protocols and a 3AOT approach (isokinetic, linear, or relative to body mass); and (3) CP was reported in watts (W) and W´ in joules (J). Studies were excluded if they involved interventions such as supplementations, hypoxia/hyperoxia, or heat exposure. Statistical analyses were conducted using Review Manager (RevMan 5.4.2.). Results are presented as standardised mean differences (SMD) with 95% confidence intervals (CI). SMDs were considered statistically significant if the 95% CI did not include 0 (P < 0.05). Heterogeneity was assessed using the I-squared statistic, and effect sizes were interpreted analogously to Cohen’s d.
RESULTS:
The analysis included 16 study results, encompassing a total of 169 participants, for both CP and W´ outcomes. Fixed-effect model pooled analysis indicated that the traditional method produced significantly lower CP values compared to the 3AOT (SMD -0.26; 95% CI: -0.47 to -0.04; P = 0.02), with no observed heterogeneity (I-squared = 0%) and a small effect size. Conversely, random-effects model pooled analysis revealed significantly higher W´ values for the traditional approach (SMD 0.74; 95% CI: 0.38 to 1.10; P < 0.01), with moderate heterogeneity observed (I-squared = 59%) and a moderate effect size.
CONCLUSION:
The traditional approach yields significantly lower CP values and significantly higher W´ values compared to the 3AOT, indicating that these methods cannot be used interchangeably in science and praxis. However, these findings do not resolve the critical question of which approach most accurately reflects the maximal metabolic steady state, and therefore, which best defines the boundary between the heavy and severe exercise intensity domains.