Exercise Intensity of Cycle-Touring Events

Abstract

The aim of the study was to analyze the exercise intensity of recreational cyclists participating in a cycling-touring event. In 14 male healthy recreational cyclists heart rate (HR) monitoring was performed during the Ötztal Radmarathon 1999 (distance: 230 km; altitude difference: 5500 m) in order to evaluate the HR response and to estimate the cardiopulmonary strains for the less-trained athlete confronted with such a marathon. Four different exercise intensities were defined as percentages of maximal HR (HR_max) as follows: recovery HR (HR_re) < 70 % of HR_max; moderate aerobic HR (HR_ma) = 70 - 80 %; intense aerobic HR (HR_ia) = 80 - 90 %; and anaerobic HR (HR_an) > 90 %.

All athletes finished the competition successfully. The mean racing time was 10 h 14 min, the average speed 22.5 km/h. The mean HR_max was 188 bpm, the average value of the measured HRs (HR_average) was 145 bpm resulting in a mean HR_average/HR_max ratio of 0.77. Athletes spent 18.5 % (1 h 54 min) of total race time within HR_re, 28 % (2 h 52 min) within HR_ma, 39.5 % (4 h 02 min) within HR_ia, and 14 % (1 h 26 min) within HR_an. The vast majority of exercise was done under “aerobic conditions” (HR_re + HR_ma + HR_ia = 86 % or 8 h 48 min) - confirming the knowledge that the aerobic energy supply is crucial for the performance of long-term exercise. The large amount of high exercise intensities (HR_ia + HR_an = 53.5 % or 5 h 30 min), however, features the intense cardiopulmonary strains evoked by such competitions. The HR response was related to the course profile with HRs significantly declining in all subjects to an extent of 10 % during the course of race.

Our findings show that the exercise intensity borne by recreational cyclists during a cycle-touring event is high and very similar to that of professionals. With respect to the high cardiovascular strains a thorough medical screening is advisable for any participant of such an event combining both high volume and high intensity loads.

Heart rate - exercise intensity - long-term exercise - recreational cycling

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