• 1
    Caspersen CJ, Powell KE, Christenson GM. Physical activity, exercise and physical fitness: definitions and distinctions for health-related research. Public Health Rep 1985; 100: 12631.
  • 2
    Cleland V, Timperio A, Salmon J, Hume C, Telford A, Crawford D. A longitudinal study of the family physical activity environment and physical activity among youth. Am J Health Promot 2011; 25: 15967.
  • 3
    Dobbins M, De Corby K, Robeson P, Husson H, Tirilis D. School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6–18. Cochrane Database Syst Rev 2009; 1: CD007651.
  • 4
    Ekeland E, Heian F, Hagen KB, Abbott J, Nordheim L. Exercise to improve self-esteem in children and young people. Cochrane Database Syst Rev 2004; 1: CD003683.
  • 5
    Janz KF, Letuchy EM, Eichenberger-Gilmore JM, et al. Early physical activity provides sustained bone health benefits later in childhood. Med Sci Sports Exerc 2010; 42: 10728.
  • 6
    Summerbell CD, Waters E, Edmunds LD, Kelly S, Brown T, Campbell KJ. Interventions for preventing obesity in children. Cochrane Database Syst Rev 2005; 3: CD001871.
  • 7
    World Health Organization. Global Recommendations on Physical Activity for Health. Geneva: World Health Organization, 2010.
  • 8
    Andersson C, Mattsson E. Adults with cerebral palsy: a survey describing problems, needs, and resources, with special emphasis on locomotion. Dev Med Child Neurol 2001; 43: 7682.
  • 9
    Jahnsen R, Villien L, Egeland T, Stanghelle JK, Holm I. Locomotion skills in adults with cerebral palsy. Clin Rehabil 2003; 18: 30916.
  • 10
    Santiago MC, Coyle CP. Leisure-time physical activity and secondary conditions in women with physical disabilities. Disabil Rehabil 2004; 26: 48594.
  • 11
    Maher CA, Williams MT, Olds T, Lane AE. Physical and sedentary activity in adolescents with cerebral palsy. Dev Med Child Neurol 2007; 49: 4507.
  • 12
    Law M, King G, King S, et al. Patterns of participation in recreational and leisure activities among children with complex physical disabilities. Dev Med Child Neurol 2006; 48: 33742.
  • 13
    Maher CA, Williams MT, Olds T, Lane AE. An internet-based physical activity intervention for adolescents with cerebral palsy: a randomized controlled trial. Dev Med Child Neurol 2010; 52: 44855.
  • 14
    Dodd KJ, Taylor NF, Graham HK. A randomized clinical trial of strength training in young people with cerebral palsy. Dev Med Child Neurol 2003; 45: 6527.
  • 15
    Dodd KJ, Foley S. Partial body-weight-supported treadmill training can improve walking in children with cerebral palsy: a clinical controlled trial. Dev Med Child Neurol 2007; 49: 1015.
  • 16
    Oftedal S, Bell KL, Mitchell LE, Davies PS, Ware RS, Boyd RN. A systematic review of the clinimetric properties of habitual physical activity measures in young children with a motor disability. Int J Pediatr 2012; 2012: 976425.
  • 17
    Clanchy KM, Tweedy SM, Boyd RN. Measurement of habitual physical activity performance in adolescents with cerebral palsy: a systematic review. Dev Med Child Neurol 2011; 53: 499505.
  • 18
    Capio CM, Sit CH, Abernethy B, Rotor ER. Physical activity measurement instruments for children with cerebral palsy: a systematic review. Dev Med Child Neurol 2010; 52: 90816.
  • 19
    Ridley K. The multimedia activity recall for children and adolescents (MARCA): development and validation (PhD thesis). Adelaide, SA: University of South Australia; 2005:335.
  • 20
    Sirard JR, Pate RR. Physical activity assessment in children and adolescents. Sports Med 2001; 31: 43954.
  • 21
    Stevens SL, Holbrook EA, Fuller DK, Morgan DW. Influence of age on step activity patterns in children with cerebral palsy and typically developing children. Arch Phys Med Rehabil 2010; 91: 18916.
  • 22
    Kuo YL, Culhane KM, Thomason P, Tirosh O, Baker R. Measuring distance walked and step count in children with cerebral palsy: an evaluation of two portable activity monitors. Gait Posture 2009; 29: 30410.
  • 23
    Aviram R, Belokopytov M, Ben-Chaim S, Rotstein A. Evaluation of energy expenditure in children with cerebral palsy using a multi-sensor accelerometer. J Sports Med Phys Fitness 2011; 51: 50614.
  • 24
    Clanchy KM, Tweedy SM, Boyd RN, Trost SG. Validity of accelerometry in ambulatory children and adolescents with cerebral palsy. Eur J Appl Physiol 2011; 111: 29519.
  • 25
    Capio C, Sit C, Abernethy B. Physical activity measurement using MTI (actigraph) among children with cerebral palsy. Arch Phys Med Rehabil 2010; 91: 128390.
  • 26
    Rowlands AV, Eston RG. Measurement and interpretation of physical activity of children. J Sports Sci Med 2007; 6: 2706.
  • 27
    Kenyon A, McEvoy M, Sprod J, Maher CA. Validity of pedometers in people with physical disabilities: a systematic review. Arch Phys Med Rehabil 2012. DOI: 10.1016/j.apmr.2012.11.030 (E-pub ahead of print).
  • 28
    Beets M, Combs C, Pitetti K, Morgan M, Bryan R, Foley J. Accuracy of pedometer steps and time for youth with disabilities. Adapt Phys Activ Q 2007; 24: 22844.
  • 29
    Dijkstra B, Zijlstra W, Scherder E, Kamsma Y. Detection of walking periods and number of steps in older adults and patients with Parkinson's disease: accuracy of a pedometer and an accelerometry-based method. Age Ageing 2008; 37: 43641.
  • 30
    Manns PJ, Orchard JL, Warren S. Accuracy of pedometry for ambulatory adults with neurological disabilities. Physiother Can 2007; 59: 20817.
  • 31
    Palisano R, Rosenbaum P, Walter S, Russell D, Wood E, Galuppi B. Development and reliability of a system to classify gross motor function in children with cerebral palsy. Dev Med Child Neurol 1997; 39: 21423.
  • 32
    McClain JJ, Hart TL, Getz RS, Tudor-Locke C. Convergent validity of 3 low cost motion sensors with the ActiGraph accelerometer. J Phys Act Health 2010; 7: 66270.
  • 33
    Schneider PL, Crouter SE, Olivera L, Bassett DR. Accuracy and reliability of 10 pedometers for measuring steps over a 400 m walk. Med Sci Sports Exerc 2003; 35: 177984.
  • 34
    de Vet R. Guide for the calculation of ICC in SPSS. In: de Vet H, Terwee C, Mokkink L, Knol D, editors. Measurement in Medicine. Cambridge: Cambridge University Press, 2011: 1149.
  • 35
    Bland JM, Altman DG. Measuring agreement in method comparison studies. Stat Methods Med Res 1999; 8: 13560.
  • 36
    Beets MW, Patton MM, Edwards S. The accuracy of pedometer steps and time during walking in children. Med Sci Sports Exerc 2005; 37: 51320.
  • 37
    Crouter SE, Schneider PL, Karabulut M, Bassett DR Jr. Validity of 10 electronic pedometers for measuring steps, distance, and energy cost. Med Sci Sports Exerc 2003; 35: 145560.
  • 38
    Orendurff MS, Segal AD, Berge JS, Flick KC, Spanier D, Klute GK. The kinematics and kinetics of turning: limb asymmetries associated with walking a circular path. Gait Posture 2006; 23: 10611.
  • 39
    Le Masurier GC, Lee SM, Tudor-Locke C. Motion sensor accuracy under controlled and free-living conditions. Med Sci Sports Exerc 2004; 36: 90510.