Workload demands in professional multi-stage cycling races of varying duration

Objetive: To analyse and compare the workload exerted by professional cyclists in 5-day, 8-day and 21-day stage races (5-SR, 8-SR, 21-SR). Methods: The study subjects were 30 professional cyclists competing in 10 5-SR, 5 8-SR and 5 21-SR. Heart rate (HR) was measured during the races and categorised into three intensity zones: Z1 (below the ventilatory threshold (VT)), Z2 (between VT and the respiratory compensation threshold (RCT)) and Z3 (above RCT). The training impulse (TRIMP) was calculated by multiplying the sum of the time spent in each zone by 1, 2 and 3, respectively. Monotony (average TRIMP/SD) and strain (total TRIMP×monotony) were also calculated for each race type. Results: The average time spent in Z3 during each stage was significantly (p<0.05) higher for 5-SR (∼31 min) and 8-SR (∼28 min) than for 21-SR (∼14 min). Daily TRIMP values in 5-SR (∼400) and 8-SR (∼395) were also higher than in 21-SR (∼370). Monotony was similar across races (∼3) but strain was about three times higher for 21-SR than for 5-SR and 8-SR. Conclusions: The cyclists’ effort by stage was less for 21-SR than for 5-SR and 8-SR. Competition strain and monotony accumulated during longer races influence the choice of strategies adopted by cyclists. It is likely that the intensity of each stage is modulated by total race duration, with longer races averaging the lowest daily workload.