title: The comparison of cross-education effect in young and elderly females from unilateral training of the elbow flexors.
abstract: BACKGROUND
  Many studies have reported the increase in strength of the untrained contralateral limb after unilateral training. The aim of this study was to compare the cross education effect in the young and elderly persons.
  
  
  METHODS
  In this quasi-experimental and pre-post study, 12 young people aged 28.25 ±3.11 years and 12 elderly persons (aged 73.08 ± 5.3 years) participated. The subjects had no history of strength training and upper limb movement impairments. Maximal isometric flexion strength in the dominant limb and the contralateral side before and after training were measured by tensiometer. Subjects performed elbow flexion exercises in the dominant side, using 3 sets of 10 repetition of the 60-70% maximal force for two weeks. Independent and paired t test were used to analyze between and within groups differences.
  
  
  RESULTS
  The results showed that short-term isometric resistive exercise led to a significant increase of strength in trained and untrained limbs in both groups (p<0.05). There was not a significant difference between the two groups in the rate of strength increase, both in the upper limb that was exercised and also in the opposite side (p> 0.05).
  
  
  CONCLUSIONS
  The increased muscle strength observed during training indicates positive effect of training in old adult. The increased muscle strength in untrained limb suggests the capacity of neuromuscular adaptation among old adults, suitable to be used in cases of limb immobility or unilateral impairment.
authors.affiliation: 1. PhD candidate in Physiotherapy, Department of physical therapy, University of Social Welfare and Rehabilitation Sciences. Tehran, Iran & Nouromuscular Rehabilitation Research Center, Semnan University of Medical Sciences, Semnan, Iran. fatemehehsani59@yahoo.com.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Ehsani
authors.affiliation: 2. PhD, PT, Associate Professor, Department of physiotherapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran & Associate Professor, Iranian Research Center on Ageing, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. afsoonnodehi@yahoo.com.
authors.forename: Afsun
authors.initials: A
authors.lastname: Nodehi-Moghadam
authors.affiliation: 3. BS, OT, Occupational therapist, Department of physical therapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. gh_hakimeh@yahoo.com.
authors.forename: Hakimeh
authors.initials: H
authors.lastname: Ghandali
authors.affiliation: 4. MSC, OT, Occupational therapist, Department of Occupational Therapy, Semnan University of Medical Sciences, Semnan, Iran. ahmadizade.z@gmail.com.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Ahmadizade
keywords: Cross education; Cross training; Elbow flexors; Elderly; Maximal isometric muscle strength