نتایج جستجو برای: mountain biking

تعداد نتایج: 26672  

Journal: :MMWR. Morbidity and mortality weekly report 2002

Physical activity is an important part of a healthy lifestyle; however, many children in the United States do not meet recommended levels of physical activity. Although walking and biking to school can increase physical activity among children, motor-vehicle traffic and other factors can make these activities difficult. The majority of U.S. children do not walk or bike to school, approximately ...

Journal: :Journal of health politics, policy and law 2008
Royce Hanson Garry Young

In Arlington, Virginia, a steady evolutionary change in biking policy during the last three decades has yielded some of the nation's best biking assets. It has a comprehensive, well-connected, highly integrated, well-mapped, and well-signed system of shared-use paved trails, bike lanes, bike routes, and other biking assets, such as workplace showers. Understanding the conditions that led to Arl...

Journal: :Preventive medicine 2014
Chia-Yuan Yu

OBJECTIVE The present study investigates the influence of income, ethnicity, and built environmental characteristics on the percentages of workers who walk/bike as well as on pedestrian/cyclist crash rates. Furthermore, income and ethnicity disparities are also explored. METHODS This study chose 162 census tracts in Austin as the unit of analysis. To explore income and ethnicity differences i...

2006
Sachin Chitta

It is well known that skilled bicycle riders can balance and propel themselves forward using motions of the handlebar. We present the complete nonlinear dynamics and control of such a pedal-less bicycle with a rider. Propulsion is achieved not by pedaling but by a cyclic motion of the steering axis of the bicycle. It is shown that this kind of actuation results in net forward motion of the bicy...

Journal: :Journal of environmental management 2010
Catherine Marina Pickering Wendy Hill David Newsome Yu-Fai Leung

Hiking, horse riding and mountain biking are popular in protected areas in Australia and the United States of America. To help inform the often contentious deliberations about use of protected areas for these three types of activities, we review recreation ecology research in both countries. Many impacts on vegetation, soils and trails are similar for the three activities, although there can be...

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