Fast Feelings
An experimental study of cycle helmets’ effect on cycling pace and emotional reactions
dr. Aslak Fyhri
Senior researcher
Department of Safety and the Environment
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§ ?
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Lack of effects in legislation
Case-control studies show positive effect of helmetLegislation for adults:
AustraliaCanada (British Colombia)New ZealandUSA
Mixed evidenceSome injury reduction, but more for other injuriesReduced cycling
Why do the laws not work?
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Risk compensation or population shift?
Risk compensationHelmets make people feel more safe
→ cycle faster
Higher cycling speed → more accidentsPopulation shift
Helmet laws →cycling a hassleNon-committed cyclists disappear
Eager, high-risk cyclists remain
Higher accident risk
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Risk compensation involves risk perception (?)
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Measuring emotions
Asking is difficult
Psychophysiological measures as indications of mental load (stress)
Differ in immediacy
Galvanic skin response, most common but impractical in field studies (traffic)
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Heart rate variability
Less dependent on physical load Easy to measure
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Previous study (Phillips, Fyhri and Sagberg 2011)
Differing effects depending on helmet habits
Only routine helmet users cycle faster with helmet
No differences in emotions (heart rate variability) according to helmet use
Not enough control with physical activity
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Procedure
Two sites, downhill slopedMakrellbekken (0.9 km)Kongsveien (1.4 km)
“Cycle for 100 meters, then stop pedalling”One hand on the steering!With and without helmet (random assign)
MeasuresSpeedHeart rate variability
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Participants(N=27)
College studentsAge 16-46 (mean 22.1)4 male/23 femaleNine regular bicyclists (> 1 t/week)15 routine helmet users (> rarely use)
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Results, speed
Accustomed users cycle faster with a helmet, unaccustomed users do not
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Results, heart rate variability
Accustomed users are less afraid with a helmet, unaccustomed users are unchanged
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Potential long term effects, risk compensation theory
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Potential long term effects, population shift theory
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Conclusion
The helmet had an effect on cycling speed and on “emotions”
But only for accustomed helmet users“Inverse” risk compensation?
yes, but most likely a transitory situation
Fyhri and Phillips (2012) Emotional reactions to cycle helmet use. Accident Analysis and Prevention in press
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