Objective: Here, we discuss cumulative fatigue based on volume and power output from 12 professional male cyclists during two consecutive editions of the Giro d'Italia. Methods: Volume and power output were recorded and described according to time at different intensity zones based on power output (Z0 lower to Z7 higher). Correlations, principal component analysis (PCA), Gaussian clustering, and two-way ANOVA were performed (type error I of 5%). Results: The higher intensity zones elicited higher power output in those shorter stages (R2 = 0.54). In contrast, the lower intensity zones were predominant in longer stages. The time spent in Z1 to Z3 (r = 0.67, 0.84, and 0.73) correlated more with stage's volume duration than time in Z4 to Z7 (r = 0.48, 0.44, and 0.51, and 0.38). The normalized volume declined between stages 2 to 4, 8 to 10, 13 to 15, and 18 to 19. Negative slopes of time spent in Z4 and Z6 occurred one or two stages before Z1 presented negative slopes. In contrast, positive slopes of higher intensity zones were observed with a negative slope of Z1. Different clusters distributions of time volume to complete the grand tour were found (p<0.05). Finally, average power in Z1, Z2, Z3, Z4, Z5, Z6, and Z7 explained 63.62%, 18.20%, 8.12%, 5.84%, 2.98%, 1.20%, and 0.02% of the total variance in the normalized time volume, respectively. Volume and power zone data can recognize cumulative fatigue and performance recovery during a grand tour. Rest days favored the performance recovery, mostly the second rest day.

The authors have declared no competing interest.

This study did not receive any funding

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