Cross Education

Possible Mechanisms for the Contralateral Effects of Unilateral Resistance Training

Abstract

Resistance training can be defined as the act of repeated voluntary muscle contractions against a resistance greater than those normally encountered in activities of daily living. Training of this kind is known to increase strength via adaptations in both the muscular and nervous systems. While the physiology of muscular adaptations following resistance training is well understood, the nature of neural adaptations is less clear. One piece of indirect evidence to indicate that neural adaptations accompany resistance training comes from the phenomenon of ‘cross education’, which describes the strength gain in the opposite, untrained limb following unilateral resistance training. Since its discovery in 1894, subsequent studies have confirmed the existence of cross education in contexts involving voluntary, imagined and electrically stimulated contractions. The crosseducation effect is specific to the contralateral homologous muscle but not restricted to particular muscle groups, ages or genders. A recent meta-analysis determined that the magnitude of cross education is ≈7.8% of the initial strength of the untrained limb. While many features of cross education have been established, the underlying mechanisms are unknown.

This article provides an overview of cross education and presents plausible hypotheses for its mechanisms. Two hypotheses are outlined that represent the most viable explanations for cross education. These hypotheses are distinct but not necessarily mutually exclusive. They are derived from evidence that highforce, unilateral, voluntary contractions can have an acute and potent effect on the efficacy of neural elements controlling the opposite limb. It is possible that with training, long-lasting adaptations may be induced in neural circuits mediating these crossed effects. The first hypothesis suggests that unilateral resistance training may activate neural circuits that chronically modify the efficacy of motor pathways that project to the opposite untrained limb. This may subsequently lead to an increased capacity to drive the untrained muscles and thus result in increased strength. A number of spinal and cortical circuits that exhibit the potential for this type of adaptation are considered. The second hypothesis suggests that unilateral resistance training induces adaptations in motor areas that are primarily involved in the control of movements of the trained limb. The opposite untrained limb may access these modified neural circuits during maximal voluntary contractions in ways that are analogous to motor learning. A better understanding of the mechanisms underlying cross education may potentially contribute to more effective use of resistance training protocols that exploit these cross-limb effects to improve the recovery of patients with movement disorders that predominantly affect one side of the body.

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References

  1. 1.

    Sale DG. Neural adaptation to resistance training. Med Sci Sports Exerc 1988; 20 (5): S135–45

    Google Scholar 

  2. 2.

    Enoka RM. Neural adaptations with chronic physical activity. J Biomech 1997; 30 (5): 447–55

    PubMed  CAS  Article  Google Scholar 

  3. 3.

    Enoka RM. Muscle strength and its development: new perspectives. Sports Med 1988; 6: 146–68

    PubMed  CAS  Article  Google Scholar 

  4. 4.

    Abernethy PJ, Jurimae L, Logan P. Acute and chronic response of skeletal muscle to resistance exercise. Sports Med 1994; 17(1), 22–38

    PubMed  CAS  Article  Google Scholar 

  5. 5.

    Baldwin KM, Haddad F. Effects of different activity and inactivity paradigms on myosin heavy chain gene expression instriated muscle. J Appl Physiol 2001; 90: 345–57

    PubMed  CAS  Article  Google Scholar 

  6. 6.

    Scripture EW, Smith n, Brown EM. On the education of muscular control and power. Stud Yale Psychol Lab 1894; 2:114–9

    Google Scholar 

  7. 7.

    Coleman A. Effect of unilateral isometric and isotonic contraction on the strength of the contralateral limb. Res. Q 1969; 40:490–5

    PubMed  CAS  Google Scholar 

  8. 8.

    Ikai M, Fukunaga T. A study on training effect on strength per cross-sectional area of muscle by means of ultrasound measurement. Eur J Appl Physiol 1970; 28: 173–80

    CAS  Article  Google Scholar 

  9. 9.

    Moritani T, DeVeries HA. Neural factors versus hypertrophy in the time course of muscle strength gain. Am J Phys Med 1979;58 (3), 115–30

    PubMed  CAS  Google Scholar 

  10. 10.

    Hakkinen K, Komi PV. Electromyographic changes during strength training and detraining. Med Sci Sports Exerc 1983;15 (6), 455–60

    PubMed  CAS  Google Scholar 

  11. 11.

    Houston ME, Froese EA, Valeriote SP, et al. Muscle performance, morphology and metabolic capacity during strength training and detraining: a one leg model. Eur J Appl Physiol 1983; 51: 25–35

    CAS  Article  Google Scholar 

  12. 12.

    Yasuda Y, Miyamura M. Cross-transfer effects of muscular training on blood flow in the ipsilateral and contralateral forearms. Eur J Appl Physiol 1983; 51: 321–9

    CAS  Article  Google Scholar 

  13. 13.

    Cannon RJ, Cafarelli E. Neuromuscular adaptations to training. J Appl Physiol 1987; 63 (6): 2396–402

    PubMed  CAS  Google Scholar 

  14. 14.

    Hortobagyi T, Larmert NJ, Hill JP. Greater cross education following training with muscle lengthening than shortening. Med Sci Sports Exerc 1997; 29: 107–12

    PubMed  CAS  Google Scholar 

  15. 15.

    Shima N, Ishida K, Katayama K, et al. Cross education of muscular strength during unilateral resistance training and detraining. Eur J Appl Physiol 2002; 86: 287–94

    PubMed  Article  Google Scholar 

  16. 16.

    Zhou S. Chronic neural adaptation to unilateral exercise: mechanisms of cross education. Exerc Sports Sci Rev 2000; 28 (4):177–84

    CAS  Google Scholar 

  17. 17.

    Davies CTM, Dooley P, McDonagh MJN, et al. Adaptation of mechanical properties of human to high force training. J Physiol 1985; 365: 277–84

    PubMed  CAS  Google Scholar 

  18. 18.

    Yue G, Cole KJ. Strength increases from the motor program: comparison of training with maximal voluntary and imagined muscle contractions. J Neurophysiol 1992; 67: 1114–23

    PubMed  CAS  Google Scholar 

  19. 19.

    Carolan B, Cafarelli E. Adaptations in coactivation after isometric resistance training. J Appl Physiol 1992; 73 (3): 911–7

    PubMed  CAS  Google Scholar 

  20. 20.

    Ploutz P, Tesch PA, Biro RL, et al. Effect of resistance training on muscle use. J Appl PhysioI 1994; 76 (4): 1675–81

    CAS  Google Scholar 

  21. 21.

    Evetovich T, Housh TJ, Housh DJ, et al. The effects of chronic isokinetic strength training of the quadriceps femoris on electromyographand muscle strength in the trained and untrained limb. J Strength Cond Res 2001; 15 (4): 439–45

    PubMed  CAS  Google Scholar 

  22. 22.

    Hortobagyi T, Scott K, Larillert NJ, et al. Cross-education of muscle strength is greater with stimulated than voluntary contractions. Motor Control 1999; 3: 205–19

    PubMed  CAS  Google Scholar 

  23. 23.

    Oakman A, Zhou S, Davie A. Cross-education effect observed in voluntary and electromyo stimulation strength training. In: Sanders RH, Gibson BJ, editors. XVII International Symposium of Biomechanics in Sports; 1999 Jun 30-Jul 6; Perth. Perth(WA): Edith Cowan University, 1999: 401–4

    Google Scholar 

  24. 24.

    Ranganathan VK, Siemionow V, Liu JZ, et al. From mental power to muscle power-gaining strength by using the mind. Neuropsychologia 2004; 42: 944–56

    PubMed  Article  Google Scholar 

  25. 25.

    Devine KL, LeVeau BF, Yack HJ. Electromyographic activity recorded from an unexercised muscle during maximal isometric exercise of the contralateral agonists and antagonists. Phys Ther 1981; 61 (6): 898–903

    PubMed  CAS  Google Scholar 

  26. 26.

    Narici MV, Roi GS, Landoni L, et al. Changes in cross-sectional area and neural activation during strength training and detrainingof human quadriceps. Eur J Appl Physiol 1989; 59:310–9

    CAS  Article  Google Scholar 

  27. 27.

    Munn J, Herbert RD, Gandevia SC. Contralateral effects of unilateral resistance training: a meta-analysis. J Appl Physiol2004; 96: 1861–6

    PubMed  CAS  Article  Google Scholar 

  28. 28.

    Herbert RD, Dean C, Gandevia SC. Fifects of real and imagined training on voluntary muscle activation during maximal isometric contractions. Acta Physiol Scand 1998; 163: 361–8

    PubMed  CAS  Article  Google Scholar 

  29. 29.

    Gleeson NP, Mercer TH. The utility of isokinetic dynamometry in the assessment of human muscle function. Sports Med 1996;21: 18–34

    PubMed  CAS  Article  Google Scholar 

  30. 30.

    Gandevia SC. Spinal and supraspinal factors in human muscle fatigue. Physiol Rev 2001; 81 (4): 1725–89

    PubMed  CAS  Google Scholar 

  31. 31.

    Munn J, Herbert RD, HancockMJ, et al. Training with unilateral resistance exercise increases contralateral strength. J Appl Physiol 2005; 99 (5): 1880–4

    PubMed  Article  Google Scholar 

  32. 32.

    Eklund B, Kaijser L, Knutsson E. Blood flow in resting (contralateral) arm and leg during isometric contraction. J Physiol 1974; 240 (1): 111–24

    PubMed  CAS  Google Scholar 

  33. 33.

    Eklund B, Kaijser L. Effect of regional alpha- and beta-adrenergic blockade on blood flow in the resting forearm during contralateral isometric hand grip. J Physiol 1976; 262 (1):39–50

    PubMed  CAS  Google Scholar 

  34. 34.

    Gandevia SC, Allen GM, Butler JE, et al. Supraspinal factors in human muscle fatigue: evidence for sub optimal output from the motor cortex. J Physiol 1996; 490 (Pt 2): 529–36

    PubMed  CAS  Google Scholar 

  35. 35.

    Gandevia SC. Neural control in human muscle fatigue: changes in muscle afferents, motoneurones and motor cortical drive[corrected]. Acta Physiol Scand 1998; 162 (3): 275–83

    PubMed  CAS  Article  Google Scholar 

  36. 36.

    Hortobagyi T, Taylor JL, Petersen NT, et al. Changes in segmental and motor cortical output with contralateral muscle contractions and altered sensory inputs in human. J Neurophysiol 2003; 90: 2451–9

    PubMed  Article  Google Scholar 

  37. 37.

    Carson RG, Riek S, Mackey DC, et al. Excitability changes in human forearm cortico spinal projections and spinal reflex pathways during rhythmic voluntary movement of the opposite limb. J Physiol 2004; 560 (Pt 3): 929–40

    PubMed  CAS  Article  Google Scholar 

  38. 38.

    Delwaide PJ, Sabatino M, Pepin JL, et al. Reinforcement of reciprocal inhibition by contralateral movements in man. Exp Neuro11988; 99: 75–98

    Article  Google Scholar 

  39. 39.

    Sabatino M, Caravaglios G, Sardo P, et al. Evidence of a contralateral motor influence on reciprocal inhibition in man. J Neural Transm Park Dis Dement Sect 1992; 4: 257–66

    PubMed  CAS  Article  Google Scholar 

  40. 40.

    Sahn YR, Jung HY, Kaelin-Lang A, et al. Excitability of the ipsilateral motor cortex during phasic voluntary hand movement. Exp Brain Res 2003; 148: 176–85

    Google Scholar 

  41. 41.

    Muellbacher W, Facchini S, Boroojerdi B, et al. Changes in motor cortex excitability during ipsilateral hand muscle activation in humans. Clin Neurophysiol 2000; 111 (2): 344–9

    PubMed  CAS  Article  Google Scholar 

  42. 42.

    Stedman A, Davey NJ, Ellaway PH. Facilitation of human first dorsal interosseous muscle responses to transcranial magnetic stimulation during voluntary contraction of the contralateral homonymous muscle. Muscle Nerve 1998; 21 (8): 1033–9

    PubMed  CAS  Article  Google Scholar 

  43. 43.

    Stinear CM, Walker KS, Byblow WD. Symmetric facilitation between motor cortices during contraction of ipsilateral hand muscles. Exp Brain Res 2001; 139: 101–5

    PubMed  CAS  Article  Google Scholar 

  44. 44.

    Liepert J, Dettmers C, Terborg C, et al. Inhibition of ipsilateral motor cortex during phasic generation of low force. Clin Neurophysiol 2001; 112 (1): 114–21

    PubMed  CAS  Article  Google Scholar 

  45. 45.

    Dettmers C, Fink GR, Lemon RN, et al. Relation between cerebral activity and force in the motor areas of the human brain. J NeurophysioI 1995; 74 (2): 802–15

    CAS  Google Scholar 

  46. 46.

    Muellbacher W, Ziemann U, Boroojerdi B, et al. Role of the human motor cortex in rapid motor learning. Exp Brain Res2001; 136: 431–8

    PubMed  CAS  Article  Google Scholar 

  47. 47.

    Muellbacher W, Ziemann U, Wissel J, et al. Early consolidation in human primary motor cortex. Nature 2002; 415 (6872):640–4

    PubMed  CAS  Article  Google Scholar 

  48. 48.

    Teixeira LA, Caminha LQ. Intermanual transfer of force control is modulated by asymmetry of muscular strength. Exp BrainRes 2003; 149: 312–9

    PubMed  Google Scholar 

  49. 49.

    Teixeira LA. Timing and force components in bilateral transfer of learning. Brain Cogn 2000; 44 (3): 455–69

    PubMed  CAS  Article  Google Scholar 

  50. 50.

    Weeks DL, Wallace SA, Anderson DI. Training with an upperlirm prosthetic simulator to enhance transfer of skill across limbs. Arch Phys Med Rehabil 2003; 84 (3): 437–43

    PubMed  Article  Google Scholar 

  51. 51.

    Carroll TJ, Riek S, Carson RG. Neural adaptation to resistance training: implications for movement control. Sports Med 2001;31 (12): 829–40

    PubMed  CAS  Article  Google Scholar 

  52. 52.

    Rutherford OM, Jones DA. The role of learning and coordination in strength training. Eur J Appl Physiol 1986; 55: 100–5

    CAS  Article  Google Scholar 

  53. 53.

    Hakkinen K, Alen M, Kallinen M, et al. Neuromuscular adaptation during prolonged strength training, detraining and restrength-training in middle-aged and elderly people. Eur JAppl Physiol 2000; 83: 51–62

    CAS  Article  Google Scholar 

  54. 54.

    Hess CW, Mills KR, Murray NM. Magnetic stimulation of the human brain: facilitation of motor responses by voluntary contraction of ipsilateral and contralateral muscles with additional observations on an amputee. Neurosci Lett 1986; 71 (2):235–40

    PubMed  CAS  Article  Google Scholar 

  55. 55.

    Ferbert A, Priori A, Rothwell JC, et al. Interhemispheric inhibition of the human motor cortex. J Physiol 1992; 453: 525–46

    PubMed  CAS  Google Scholar 

  56. 56.

    Di Lazzaro V, Oliviero A, Profice P, et al. Direct demonstration of interhemispheric inhibition of the human motor cortex produced by transcranial magnetic stimulation. Exp Brain Res1999; 124: 520–4

    PubMed  Article  Google Scholar 

  57. 57.

    Hanajima R, Ugawa Y, Machii K, et al. Interhemispheric facilitation of the hand motor area in humans. J Physiol 2001; 531(Pt 3): 849–59

    PubMed  CAS  Article  Google Scholar 

  58. 58.

    Ugawa Y, Hanajima R, Kanazawa I. Interhemispheric facilitation of the hand area of the human motor cortex. Neurosci Lett 1993; 160 (2): 153–5

    PubMed  CAS  Article  Google Scholar 

  59. 59.

    Warbrooke SA, Byblow WD. Modulation of interhemispheric inhibition during passive movement of the upper limb reflects changes in motor cortical excitability. Exp Brain Res 2004; 156 (1), 11–9

    PubMed  Article  Google Scholar 

  60. 60.

    Asanuma H, Okuda O. Effects of transcallosal volleys on pyramidal tract cell activity of cat. J Neurophysiol 1962; 25:198–208

    PubMed  CAS  Google Scholar 

  61. 61.

    Matsunami K, Hamada I. Effects of stimulation of corpus callosum on precentral neuron activity in the awake monkey. J Neurophysiol 1984; 52 (4): 676–91

    PubMed  CAS  Google Scholar 

  62. 62.

    Gerloff C, Cohen LG, Floeter MK, et al. Inhibitory influence of the ipsilateral motor cortex on responses to stimulation of the human cortex and pyramidal tract. J Physiol 1998; 510 (Pt 1):249–59

    PubMed  CAS  Article  Google Scholar 

  63. 63.

    Cracco RQ, Amassian VB, Maccabee PJ, et al. Comparison of human transcallosal responses evoked by magnetic coil and electrical stimulation. Electroencephalogr Clin Neurophysiol 1989; 74 (6): 417–24

    PubMed  CAS  Article  Google Scholar 

  64. 64.

    Lagerquist O, Zehr EP, Docherty D. Increased spinal reflex excitability is not associated with neural plasticity underlying the cross-education effect. J Appl Physiol 2006; 100: 83–90

    PubMed  Article  Google Scholar 

  65. 65.

    Hultborn H, Illert M, Santini M. Convergence on interneurones mediating the reciprocal Ia inhibition of motoneurones I: disynapticIa inhibition of Ia inhibitory interneurones. Acta Physiol Scand 1976; 96 (2): 193–201

    PubMed  CAS  Article  Google Scholar 

  66. 66.

    Baldissera F, Cavallari P, Fournier E, et al. Evidence for mutual inhibition of opposite Ia interneurones in the human upper limb. Exp Brain Res 1987; 66 (1): 106–14

    PubMed  CAS  Article  Google Scholar 

  67. 67.

    Lundberg A, Weight F. Signalling of reciprocal 1 a inhibition by the ventral spinocerebellar tract. Brain Res 1970; 23 (1):109–11

    PubMed  CAS  Article  Google Scholar 

  68. 68.

    Hultborn H, Jankowska E, Lindstrom S, et al. Recurrent inhibition from the motor axon collaterals of transmission in the la inhibitory pathway to motoneurones. J Physiol 1971; 215:591–612

    PubMed  CAS  Google Scholar 

  69. 69.

    Hultborn H, Jankowska E, Lindstrom S. Relative contribution from different nerves to recurrent depression of la IPSPs inmotoneurones. J Physiol 1971; 215: 637–64

    PubMed  CAS  Google Scholar 

  70. 70.

    Katz R, Pierrot-Deseilligny E. Recurrent inhibition in humans. Prog Neurobiol 1998; 57 (3): 325–55

    Article  Google Scholar 

  71. 71.

    Harrison PJ, Zytnicki D. Crossed action of group 1 muscle afferents in the cat. J Physiol 1984; 356: 263–73

    PubMed  CAS  Google Scholar 

  72. 72.

    Delwaide PJ, Pepin JL. The influence of contralateral primary afferents on la inhibitory interneurones in humans. J Physiol 1991; 439: 161–79

    PubMed  CAS  Google Scholar 

  73. 73.

    Sabatino M, Sardo P, Ferraro G, et al. Bilateral reciprocal organisation in man: focus on 1A interneurone. J Neural Transm Gen Sect 1994; 96: 31–9

    PubMed  CAS  Article  Google Scholar 

  74. 74.

    Jankowska E, Padel Y, Zarzecki P. Crossed disynaptic inhibition of sacral motoneurones. J Physiol 1978; 285: 425–44

    PubMed  CAS  Google Scholar 

  75. 75.

    Hultborn H, Pierror-Deseilligny E. Changes in recurrent inhibition during voluntary soleus contractions in man studied by an H-reflex technique. J Physiol 1979; 297: 229–51

    PubMed  CAS  Google Scholar 

  76. 76.

    Strens LH, Fogelson N, Shanahan P, et al. The ipsilateral human motor cortex can functionally compensate for acute contralateral motor cortex dysfunction. Curr Biol 2003; 13 (14): 1201–5

    PubMed  CAS  Article  Google Scholar 

  77. 77.

    Siebner HR, Rothwell J. Transcranial magnetic stimulation: new insights into representational cortical plasticity. Exp Brain Res 2003; 148 (1): 1–16

    PubMed  Article  Google Scholar 

  78. 78.

    Hallett M, Wassermann EM, Pascual-Leone A, et al. Repetitive transcranial magnetic stimulation. Electroencephalogr Clin Neurophysiol Suppl 1999; 52: 105–13

    PubMed  CAS  Google Scholar 

  79. 79.

    Cook TW. Studies in cross education I: mirror tracing the starshaped maze. J Exp Psychol 1933; 16: 144–60

    Article  Google Scholar 

  80. 80.

    Parlow SE, Kinsbourne M. Asymmetrical transfer of braille acquisition between hands. Brain Lang 1990; 39 (2): 319–30

    PubMed  CAS  Article  Google Scholar 

  81. 81.

    Thut G, Cook ND, Regard M, et al. Intermanual transfer of proximal and distal motor engrams in humans. Exp Brain Res 1996; 108 (2): 321–7

    PubMed  CAS  Article  Google Scholar 

  82. 82.

    Hicks RE, Gualtieri CT, Schroeder SR. Cognitive and motor corrponents of bilateral transfer. Am J Psychol 1983; 96:223–8

    Article  Google Scholar 

  83. 83.

    Morton SM, Lang CE, Bastian AJ. Inter- and intra-limb generalization of adaptation during catching. Exp Brain Res 2001; 141(4),43–45

    Article  Google Scholar 

  84. 84.

    Choe CS, Walsh RB. Variables affecting the intermanual transfer and decay after prism adaptation. J Exp Psychol 1974; 102:1076–84

    PubMed  CAS  Article  Google Scholar 

  85. 85.

    Elliot D, Roy EA. Interlimb transfer after adaptation to visual displacement: patterns predicted from the functional closeness of limb neural control centres. Perception 1981; 10: 383–9

    Article  Google Scholar 

  86. 86.

    Sathian K, Zangaladze A. Perceptual learning in tactile hyperacuity: complete intermanual transfer but limited retention. Exp Brain Res 1998; 118 (1): 131–4

    PubMed  CAS  Article  Google Scholar 

  87. 87.

    Gordon AM, Forssberg H, Iwasaki N. Formation and lateralization of internal representations underlying motor commands during precision grip. Neuropsychologia 1994; 32 (5): 555–68

    PubMed  CAS  Article  Google Scholar 

  88. 88.

    Dizio P, Lackner JR. Motor adaptation to Coriolis force perturbations of reaching movements: end point but not trajectory adaptation transfers to the nonexposed arm. J Neurophysiol 1995; 74 (4): 1787–92

    PubMed  CAS  Google Scholar 

  89. 89.

    Farthing JP, Chilibeck PD, Binsted G. Cross-education of arm muscular strength is unidirectional in right-handed individuals. Med Sci Sports Exerc 2005; 37 (9): 1594–600

    PubMed  Article  Google Scholar 

  90. 90.

    Bussey TJ, Wise SP, Murray EA. Interaction of ventral and orbital prefrontal cortex with inferotemporal cortex in conditional visuomotor learning. Behav Neurosci 2002; 116 (4):703–15

    PubMed  Article  Google Scholar 

  91. 91.

    Bussey TJ, Wise SP, Murray EA. The role of ventral and orbital prefrontal cortex in conditional visuomotor learning and strategy use in rhesus monkeys (Macaca mulatta). Behav Neurosci 2001; 115 (5): 971–82

    PubMed  CAS  Article  Google Scholar 

  92. 92.

    White IM, Wise SP. Rule-dependent neuronal activity in the prefrontal cortex. Exp Brain Res 1999; 126 (3): 315–35

    PubMed  CAS  Article  Google Scholar 

  93. 93.

    Sanes IN. Neocortical mechanisms in motor learning. Curr Opin Neurobiol 2003; 13 (2): 225–31

    PubMed  CAS  Article  Google Scholar 

  94. 94.

    Shadmehr R, Holcorm HH. Neural correlates of motor memory consolidation. Science 1997; 277 (5327): 821–5

    PubMed  CAS  Article  Google Scholar 

  95. 95.

    Doyon J, Penhune V, Ungerleider LG. Distinct contribution of the cortico-striatal and cortico-cerebellar systems to motor skill learning. Neuropsychologia 2003; 41 (3): 252–62

    PubMed  Article  Google Scholar 

  96. 96.

    Curtis HJ. Intracortical connections of corpus callosum as indicated by evoked potentials. J Neurophysiol 1940; 3: 407–13

    Google Scholar 

  97. 97.

    Eliassen JC, Baynes K, Gazzaniga MS. Direction information coordinated via the posterior third of the corpus callosum during bimanual movements. Exp Brain Res 1999; 128 (4):573–7

    PubMed  CAS  Article  Google Scholar 

  98. 98.

    Gazzaniga MS. Cerebral specialization and interhemispheric communication: does the corpus callosum enable the humancondition? Brain 2000; 123 (PI: 7): 1293–326

    PubMed  Article  Google Scholar 

  99. 99.

    Rouiller EM, Babalian A, Kazennikov O, et al. Transcallosal connections of the distal forelimb representations of the primary and supplementary motor cortical areas in macaque monkeys. Exp Brain Res 1994; 102 (2): 227–43

    PubMed  CAS  Article  Google Scholar 

  100. 100.

    Gould HJ, Cusick CG, Pons TP, et al. The relationship of corpus callosum connections to electrical stimulation maps of motor, supplementary motor, and the frontal eye fields in owl monkeys. J Comp Neurol 1986; 247 (3): 297–325

    PubMed  Article  Google Scholar 

  101. 101.

    Carson RG. Neural pathways mediating bilateral interactions between the upperlirms. Brain Res Rev 2005; 49 (3): 641–62

    PubMed  CAS  Article  Google Scholar 

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Acknowledgements

This work is funded by the Australian Research Council. The authors thank Professors Simon Gandevia and Richard Carson for valuable comments on the review. The authors have no conflicts of interest that are directly relevant to the content of this review.

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Correspondence to Michael Lee.

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Lee, M., Carroll, T.J. Cross Education. Sports Med 37, 1–14 (2007). https://doi.org/10.2165/00007256-200737010-00001

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Keywords

  • Transcranial Magnetic Stimulation
  • Resistance Training
  • Maximal Voluntary Contraction
  • Strength Gain
  • Neural Adaptation