Perceived risk for falls and decision-making in riding raised ramps in mountain biking: a pilot study

Mountain biking (MTB) is a challenging activity where riders face constant decisions on whether to attempt technical paths or features (e.g., wooden ramps and jumps) that pose risk for falls and injuries. Risk homeostasis theory posits that riders pursue an optimal non-zero level of risk that balances the rewards of attempting challenging features with the need to avoid unreasonable risk for injury. Little is known on how riders judge risk, and the level of risk that riders deem unacceptable. We conducted experiments with experienced MTB riders (n = 17) to examine how their willingness to ride raised wooden ramps depended on their perceived probability for falling (P_f) and their perceived probability for injury in the event of a fall (P_i) while riding the ramp. In one experiment, participants viewed ramps of varying widths and heights and described their willingness to ride each ramp, along with P_f and P_i. We found that P_f and P_i were independent predictors of willingness to attempt ramps. Moreover, the product P_f*P_i (the perceived risk for injury in attempting the ramp) was a stronger predictor than P_f or P_i alone. In a second experiment, participants viewed ramps of different widths, and reported the maximum (threshold) height where they would ride each ramp, along with P_f and P_i. We found that P_f*P_i at the threshold height, averaging 13%, did not vary with ramp width. We conclude that decisions on riding ramps are based on the product P_f*P_i. On average, riders refused to ride ramps when P_f*P_i exceeded 13%.