Shorter CWR cycling tests as proxies for longer tests in highly trained cyclists

<p class="MsoNormal">Severe-intensity constant work rate (<span>CWR) cycling tests </span>simulate the high-intensity competition environment<span> and are </span>useful for monitoring training progression and adaptation, yet <span>impose significant </span>physiological and psychological strain, require substantial recovery, and may disrupt athlete <span>training or competition preparation.</span> A brief, minimally fatiguing test providing comparable information is desirable.<strong><em> </em></strong></p> <p class="MsoNormal"><strong>Purpose</strong>: To determine whether physiological variables measured during, and functional decline in maximal power output immediately after, a <span>2-min</span> CWR test can act as a proxy for <span>4-min</span> test outcomes.</p> <p class="MsoNormal"><strong>Methods</strong>: <span>Physiological stress (</span><span>V̇O₂ kinetics, heart rate, blood lactate concentrations </span>([La^-]_b)<span>) </span><span>was monitored and performance fatigability was estimated (</span>as p<span>re-to-post-CWR changes in 10-s sprint power) during 2- and 4-min CWR tests in 16 high-level cyclists (</span>V̇O_2peak=64.4±6.0 ml∙kg^-1∙min^-1). <span>The relationship between the 2- and 4-min CWR tests and the physiological variables that best relate to the performance fatigability were investigated.</span></p> <p class="MsoNormal"><strong>Results</strong>: The 2-min CWR test evoked a smaller decline in sprint mechanical power (32% vs. 47%, <em>p</em>&lt;0.001). Both the physiological variables (r=0.66-0.96) and sprint mechanical power (r=0.67-0.92) were independently and strongly correlated between 2- and 4-min tests. Differences in <span>V̇O_2peak</span> and [La^-]_b in both CWR tests were strongly associated with the decline in sprint mechanical power.</p> <p class="MsoNormal"><strong>Conclusion</strong>: Strong correlations between 2- and 4-min severe-intensity CWR test outcomes indicated that the shorter test can be used as a proxy for the longer test. A shorter test may be more practical within the elite performance environment due to lower physiological stress and performance fatigability and should have less impact on subsequent training and competition preparation.</p>