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- Fardelin, Gustav, et al.
(författare)
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Hand nerve function after mountain bike cycling
- 2022
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Ingår i: Journal of Science and Cycling. - : CYCLING RESEARCH CENTER. - 2254-7053. ; 11:3, s. 23-32
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Hand-arm vibrations can cause permanent injuries and temporary changes affecting the sensory and circulatory systems in the hands. Vibrational effects have been thoroughly studied within the occupational context concerning work with handheld vibrating tools. Less is known about vibrational exposure and risk of effects during cycling. In the present study, 10 cyclists were recruited for exposure measurements of hand-arm vibrations during mountainbike cycling on the trail, and the effects on the nerve function were examined with quantitative sensory testing (QST) before and after the ride. The intervention group was compared to a control group that consisted of men exposed to hand-arm vibrations from a polishing machine. The results of the QST did not statistically significantly differ between the intervention and study groups. The intervention group showed a lesser decrease in vibration perception in digitorum II, digitorum V, and hand grip strength than the control group. It was concluded that no acute effects on nerve function in the dominant hand were measured after mountain bike cycling on the trail, despite high vibration doses through the handlebars.
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| 2. |
- Hurst, Howard T, et al.
(författare)
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GPS-Based Evaluation of Activity Profiles in Elite Downhill Mountain Biking and the Influence of Course Type
- 2013
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Ingår i: Journal of Science and Cycling. - : Cycling Research Center; Faculty of Sport Sciences - University of Granada. - 2254-7053. ; 2:1, s. 25-32
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to profile the activity patterns of elite downhill (DH) mountain bikers during off-road descending, and to determine the influence of course types on activity patterns. Six male elite DH mountain bikers (age 20 ± 2 yrs; stature 178.8 ± 3.1 cm; body mass 75.0 ± 3.0 kg) performed single runs on one man-made (MM) and one natural terrain (NT) DH courses under race conditions. A 5 Hz global positioning systems (GPS) unit, including a 100 Hz triaxial accelerometer, was positioned in a neoprene harness between the C7 and T2 vertebrae on each rider. GPS was used to determine the temporal characteristics of each run for velocity, run time, distance, effort, heart rate (HR), rider load (RLd) which reflects instantaneous rate of change in acceleration, and accumulated rider load (RLdAcc), which reflects change in acceleration over the event duration. Significant differences were found between NT and MM courses for mean velocity (p<.001), peak velocity (p=.014), mean RLd (p=.001) and peak RLd (p=.002). Significant differences were also found both within and between courses for all velocity parameters, when analysed by intensity zone (p<.05). No significant differences were found between courses for HR parameters by zone, though significant differences were revealed between HR zones within courses (p<.05). This study indicates that course terrain has a significant impact on the activity profiles of DH and that GPS can provide a practical means of monitoring these differences in activity.
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| 4. |
- Priego Quesada, Jose Ignacio, et al.
(författare)
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Importance of static adjustment of knee angle to determine saddle height in cycling
- 2016
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Ingår i: Journal of Science and Cycling. - 2254-7053. ; 5:1, s. 26-31
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Tidskriftsartikel (refereegranskat)abstract
- Knee flexion angle is used to determine saddle height during pedaling. However, it is unclear how knee flexion angle at upright standing posture affects measures and interpretation of knee flexion angle during cycling. The objective of this study was to highlight the importance of adjusting knee angle during pedaling according to the knee angle at upright posture. Seventeen cyclists performed three 10 min cycling trials at different saddle heights to induce knee flexion angles (40º, 30º or 20º when crank was at the 6 o’clock position). Knee flexion angle was determined at the sagittal plane during cycling using a 2D motion analysis system. Alteration of saddle height was performed by subtracting the knee flexion determined during an upright standing posture from the observed knee flexion during cycling. Repeatability of knee angles at upright posture in the three trials was very good (ICC=0.73). A reduction in knee flexion angle of 10.6° (95%CI [8.6, 12.6º]) during cycling was found using the adjustment for upright standing posture (p<0.01; effect size>3.0). As a result, saddle height is affected by adjustments based on knee angle measured in upright standing posture. Determining saddle height without adjusting knee angle for upright standing posture could lead to errors with possible effects on performance and/or injury risk.
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