Research in Developmental Disabilities 53 (2016) 367–376 Contents lists available at ScienceDirect Research in Developmental Disabilities The effect of a combined strength and proprioceptive training on muscle strength and postural balance in boys with intellectual disability: An exploratory study Hiba Kachouri a,∗ , Rihab Borji a , Rym Baccouch a,b , Rabeb Laatar a , Haithem Rebai a , Sonia Sahli a a Research Unit Education, Motricité, Sport et Santé, UR15JS01, High Institute of Sport and Physical Education of Sfax, University of Sfax, Tunisia b Faculty of Sciences of Bizerte, University of Carthage, Tunisia a r t i c l e i n f o Article history: Received 1 October 2015 Received in revised form 6 March 2016 Accepted 6 March 2016 Keywords: Intellectual disability Postural balance Muscle strength Combined strength and proprioceptive training a b s t r a c t The aim of our study was to investigate the effect of a combined strength and proprio- ception training (CSPT) program on muscle strength and postural balance in children with intellectual disability (ID). The maximum voluntary contraction (MVC) and postural param- eters (CoP Vm , CoP LX , CoP LY ) of 20 children with ID were recorded before and after 8 weeks of a CSPT program. The participants were divided into two groups: an experimental group who attended a CSPT program and a control group who continued with daily activities. In the trained group, the MVC increased significantly (p < 0.001) after the training period and the postural parameters decreased significantly in Double-Leg Stance (DLS) and One-Leg Stance (OLS) during the firm surface condition as well as in the DLS during the foam sur- face condition; in both eyes open (EO) and eyes closed (EC) conditions. A CSPT program improves postural balance in children with ID could be due to the enhancement in muscle strength and proprioceptive input integration. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction Postural performances are relevant to check in individuals with intellectual disability (ID) since posture serves as a reference frame for the production of accurate movements that are vital for the activities of daily living like walking, stepping up the stairs, or standing in a bus. Previous studies showed that individuals with ID present several balance (Cabeza-Ruiz et al., 2011; Srikanth, Cassidy, Joiner, & Teeluckdharry, 2011; Zur, Ronen, Melzer, & Carmeli, 2013) and gait (Cleaver, Hunter, & Ouellette-Kuntz, 2009; Galli et al., 2008; Smith, Kubo, Black, Holt, & Ulrich, 2007) disorders. These balance and gait problems are one of the well-established risk factors for falling as previously reviewed (Enkelaar, Smulders, van Schrojenstein Lantman- de Valk, Geurts, & Weerdesteyn, 2012). The impairment of postural balance in individuals with ID was explained by deficits in visual (Little, Woodhouse, Lauritzen, & Saunders, 2007; John, Bromham, Woodhouse, & Candy, 2004; Woodhouse et al., 1996), somesthesic (Carvalho & Almeida, 2009; Golubovic, Maksimovic, Golubovic, & Glumbic, 2012; Hale, Miller, Barach, Skinner, & Gray, 2009), and vestibular inputs (Rogers, Hepburn, & Wehner, 2003; Zur et al., 2013). Moreover, some individuals ∗ Corresponding author at: Institut Supérieur de Sport et de l’Education Physique de Sfax, Route de l’Aérodrôme, Km 3.5, BP 1068, 3000 Sfax, Tunisia. E-mail addresses: hiba.kachouri9@gmail.com (H. Kachouri), borji-rihab1@hotmail.fr (R. Borji), baccoucherim@yahoo.fr (R. Baccouch), laater.rabeb86@gmail.com (R. Laatar), haithem.rebai@yahoo.fr (H. Rebai), Sonia.sahli@yahoo.fr (S. Sahli). http://dx.doi.org/10.1016/j.ridd.2016.03.003 0891-4222/© 2016 Elsevier Ltd. All rights reserved.