Edinburgh Napier University

  Limited information is currently available regarding the hand-arm vibration (HAV) exposure 5 for professional off-road cyclists. Previous reports have suggested that commuting and 6 recreational cyclists are at risk of exceeding exposure limit values (ELV) in a single ride. 7 Therefore, further investigation of HAV exposure in competitive mountain biking is 8 warranted. Partial and total eight hour exposure data (Ai(8), A(8), ms⁻²) were computed for a 9 national level mountain bike enduro competitions. Hand-arm vibrations were measured using 10 a tri-axial accelerometer recording at a frequency of 3.2 kHz mounted on the handlebar and 11 accelerations were quantified after frequency weighting filters were applied (Wh). The data 12 presented shows that HAV exposure during one day of competitive enduro mountain bike 13 racing exceeds ELV (mean race exposure = 5.84 ms⁻² , minimum = 5.47ms⁻² , maximum = 14 6.61ms⁻²) and is greater than the HAV exposure observed in recreational cycling. This 15 suggests that further work is required to determine the exposure associated with changes in 16 equipment, technique and international racing events in professional athletes.