Effect of an Aerodynamic Helmet on Head Temperature, Core Temperature, and Cycling Power Compared With a Traditional Helmet

Abstract

Nonvented "aerodynamic helmets" reduce wind resistance but may increase head (Th) and gastrointestinal (Tgi) temperature and reduce performance when worn in hot conditions. This study tested the hypothesis that Th and Tgi would be greater during low-intensity cycling (LIC) in the heat while wearing an aero helmet (AERO) vs. a traditional vented racing helmet (REG). This study also tested the hypothesis that Th, Tgi, and finish time would be greater, and power output would be reduced during a self-paced time trial in the heat with AERO vs. REG. Ten highly trained heat-acclimated endurance athletes conducted LIC (50% V[Combining Dot Above]O2max, LIC) and a high-intensity 12-km self-paced time trial (12-km TT) on a cycle ergometer in 39° C on 2 different days (AERO and REG), separated by >48 hours. During LIC, Th was higher at minute 7.5 and all time points thereafter in AERO vs. REG (p < 0.05). Similarly, during the 12-km TT, Th was higher at minutes 12.5, 15, and 17.5 in AERO vs. REG (p < 0.05). Heart rate (HR) and Tgi increased during LIC and during 12-km TT (both p < 0.001); however, no significant interaction (helmet × time) existed for HR or Tgi at either intensity (all p > 0.05). No group differences existed for finish time or power output during the 12-km TT (both p > 0.05). In conclusion, Th becomes elevated during cycling in the heat with an aero helmet compared with a traditional vented racing helmet during LIC and high-intensity cycling, yet Tgi and HR responses are similar irrespective of helmet type and Th. Furthermore, the higher Th that develops when an aero helmet is worn during cycling in the heat does not affect power output or cycling performance during short-duration high-intensity events.

Effect of vented helmets on heat stress during wildland firefighter simulation

“…These results are supported by previous investigations examining the effect of vented helmets on heat dissipation and physiological strain (Holland et al 2002;Lee et al 2013).…”

“…5). This diverges from the results of Lee et al whose 2013 study found no differences in power output between a vented standard bicycle helmet and an unvented aerodynamic helmet during a 12-km cycling time trial (Lee et al 2013). Their shorter study duration in combination with higher power outputs (%VO 2max ) and higher ambient temperatures may account for this discrepancy.…”

“…A study examined differences between a traditional vented cycling helmet and a non-vented aerodynamic helmet in highly trained cyclists at ,398C while doing either low-intensity cycling (30 min at 50% VO 2max ) or a self-paced 12-km time trial (Lee et al 2013). In the low-intensity cycling trial, T HELMET of the non-vented helmet was ,0.58C higher than the traditional vented helmet at the end of the 30 min.…”

“…Investigations have shown that the American football helmet increases the rate of core temperature elevation during exercise while decreasing the time to exhaustion (Armstrong et al 2010) and impairments in cognition have also been observed in cricketers (Neave et al 2004). It was also found that an unvented aerodynamic bicycle helmet resulted in greater head temperature elevation compared with a vented traditional helmet (Lee et al 2013). A previous investigation by our group found the WLFF helmet contributes to heat accumulation, perceived head heat and redirection of blood flow to the head compared with not wearing a helmet (Gurney et al 2021).…”

Kühlen Kopf bewahren

“…Dadurch lassen sich Fragen beantworten wie jene, ob ein aerodynamischerer, jedoch schlecht belüfteter Helm einem gut belüfteten Helm vorgezogen werden soll oder wie sich neue Belüftungskonzepte für aerodynamische Fahrradhelme auswirken. Die erstere Fragestellung wurde mit Studienteilnehmern für ein Kurzdistanzzeitfahren über 12 km untersucht . Dabei ergaben sich für den schlechter belüfteten, jedoch aerodynamischeren Helm eine um 0,4 °C erhöhte Kopftemperatur sowie eine um 0,2 °C erhöhte Körperkerntemperatur, verglichen mit dem gut belüfteten Helm.…”