Downslope walking (DSW) is an eccentric-based exercise intervention that promotes neuroplasticity of spinal reflex circuitry by inducing depression of Soleus Hoffman (H)-reflexes in young, neurologically unimpaired adults.
OBJECTIVE:
The objective of the study was to evaluate the effects of DSW on spinal excitability (SE) and walking function (WF) in people with multiple sclerosis (PwMS).
METHODS:
Our study comprised two experiments on 12 PwMS (11 women; 45.3±11.8 years). Experiment 1 evaluated acute effects of a single 20-minute session of treadmill walking at three different walking grades on SE, 0% or level walking (LW), – 7.5% DSW, and – 15% DSW. Experiment 2 evaluated the effects of 6 sessions of DSW, at – 7.5% DSW (with second session being – 15% DSW) on SE and WF.
RESULTS:
Experiment 1 showed significantly greater acute % H-reflex depression following – 15% DSW compared to LW (p = 0.02) and – 7.5% DSW (p = 0.05). Experiment 2 demonstrated significant improvements in WF. PwMS who showed greater acute H-reflex depression during the – 15% DSW session also demonstrated greater physical activity, long-distance WF, and the ability to have greater H-reflex depression after DSW training. Significant changes were not observed in regards to SE.
CONCLUSIONS:
Though significant changes were not observed in SE after DSW training, we observed an improvement in WF which merits further investigation of DSW in PwMS.
ArnoldE., FarmerB., KeightleyM., LeeD., RigelT., HoqueM., & SabatierM.J. (2017). Walking duration and slope steepness determine the effect of downslope walking on the soleus H-reflex pathway. Neurosci Lett, 639, 18–24. doi:10.1016/j.neulet.2016.12.048
2.
BohannonR.W., & SmithM.B. (1987). Interrater reliability of a modified Ashworth scale of muscle spasticity. Phys Ther, 67(2), 206–207.
3.
BorgG. (1978). Subjective effort and physical abilities. Scand J Rehabil Med Suppl, 6, 105–113.
4.
CardaS., InvernizziM., BaricichA., CognolatoG., & CisariC. (2013). Does altering inclination alter effectiveness of treadmill training for gait impairment after stroke? A randomized controlled trial. Clin Rehabil, 27(10), 932–938. doi:10.1177/0269215513485592
5.
CattaneoD., RegolaA., & MeottiM. (2006). Validity of six balance disorders scales in persons with multiple sclerosis. Disabil Rehabil, 28(12), 789–795. doi:10.1080/09638280500404289
6.
ChoiL., LiuZ., MatthewsC.E., & BuchowskiM.S. (2011). Validation of accelerometer wear and nonwear time classification algorithm. Med Sci Sports Exerc, 43(2), 357–364. doi:10.1249/MSS.0b013e3181ed61a3
DaviesB.L., ArpinD.J., LiuM., ReelfsH., VolkmanK.G., HealeyK.,... KurzM.J. (2016). Two Different Types of High-Frequency Physical Therapy Promote Improvements in the Balance and Mobility of Persons With Multiple Sclerosis. Arch Phys Med Rehabil, 97(12), 2095–-2101.e2093. doi:10.1016/j.apmr.2016.05.024
9.
DuclayJ., & MartinA. (2005). Evoked H-reflex and V-wave responses during maximal isometric, concentric, and eccentric muscle contraction. J Neurophysiol, 94(5), 3555–3562. doi:10.1152/jn.00348.2005
10.
DuttaR., & TrappB.D. (2011). Mechanisms of Neuronal Dysfunction and Degeneration in Multiple Sclerosis. Prog Neurobiol, 93(1), 1–12. doi:10.1016/j.pneurobio.2010.09.005
11.
FangY., SiemionowV., SahgalV., XiongF., & YueG.H. (2001). Greater Movement-Related Cortical Potential During Human Eccentric Versus Concentric Muscle Contractions. Journal of Neurophysiology, 86(4), 1764–1772.
12.
GervasoniE., CattaneoD., & JonsdottirJ. (2014). Effect of treadmill training on fatigue in multiple sclerosis: A pilot study. Int J Rehabil Res, 37(1), 54–60. doi:10.1097/mrr.0000000000000034
13.
GiesserB., Beres-JonesJ., BudovitchA., HerlihyE., & HarkemaS. (2007). Locomotor training using body weight support on a treadmill improves mobility in persons with multiple sclerosis: A pilot study. Mult Scler, 13(2), 224–231. doi:10.1177/1352458506070663
14.
HauserS.L., & OksenbergJ.R. (2006). The neurobiology of multiple sclerosis: Genes, inflammation, and neurodegeneration. Neuron, 52(1), 61–76. doi:10.1016/j.neuron.2006.09.011
15.
HobartJ.C., RiaziA., LampingD.L., FitzpatrickR., & ThompsonA.J. (2003). Measuring the impact of MS on walking ability: The 12-Item MS Walking Scale (MSWS-12). Neurology, 60(1), 31–36.
16.
HoesslyM. (1991). Use of eccentric contraction of muscle to increase range of movement in the upper motor neurone syndrome. Physiotherapy Theory and Practice, 7(2), 91–101. doi:10.3109/09593989109106959
17.
HuangC.Y., WangC.H., & HwangI.S. (2006). Characterization of the mechanical and neural components of spastic hypertonia with modified H reflex. J Electromyogr Kinesiol, 16(4), 384–391. doi:10.1016/j.jelekin.2005.09.001
18.
HunterL.C., HendrixE.C., & DeanJ.C. (2010). The cost of walking downhill: Is the preferred gait energetically optimal?J Biomech, 43(10), 1910–1915. doi:10.1016/j.jbiomech.2010.03.030
19.
HutchinsonB., ForwellS.J., BennettS., BrownT., KarpatkinH., & MillerD. (2009). Toward a Consensus on Rehabilitation Outcomes in MS: Gait and Fatigue. International Journal of MS Care, 11(2), 67–78. doi:10.7224/1537-2073-11.2.67
LagerquistO., ZehrE.P., BaldwinE.R., KlakowiczP.M., & CollinsD.F. (2006). Diurnal changes in the amplitude of the Hoffmann reflex in the human soleus but not in the flexor carpi radialis muscle. Exp Brain Res, 170(1), 1–6. doi:10.1007/s00221-005-0172-1
22.
LeechK.A., KinnairdC.R., HolleranC.L., KahnJ., & HornbyT.G. (2016). Effects of Locomotor Exercise Intensity on Gait Performance in Individuals With Incomplete Spinal Cord Injury. Phys Ther, 96(12), 1919–1929. doi:10.2522/ptj.20150646
23.
ManellaK.J., RoachK.E., & Field-FoteE.C. (2013). Operant conditioning to increase ankle control or decrease reflex excitability improves reflex modulation and walking function in chronic spinal cord injury. J Neurophysiol, 109(11), 2666–2679. doi:10.1152/jn.01039.2011
24.
MoritaH., CroneC., ChristenhuisD., PetersenN.T., & NielsenJ.B. (2001). Modulation of presynaptic inhibition and disynaptic reciprocal Ia inhibition during voluntary movement in spasticity. Brain, 124(Pt 4), 826–837.
25.
NoseworthyJ.H. (1999). Progress in determining the causes and treatment of multiple sclerosis. Nature, 399. (6738 Suppl), A40–47.
Phan-BaR., PaceA., CalayP., GrodentP., DouchampsF., HydeR.,... BelachewS. (2011). Comparison of the timed 25-foot and the 100-meter walk as performance measures in multiple sclerosis. Neurorehabil Neural Repair, 25(7), 672–679. doi:10.1177/1545968310397204
29.
PiluttiL.A., LelliD.A., PaulsethJ.E., CromeM., JiangS., RathboneM.P., & HicksA.L. (2011). Effects of 12 weeks of supported treadmill training on functional ability and quality of life in progressive multiple sclerosis: A pilot study. Arch Phys Med Rehabil, 92(1), 31–36. doi:10.1016/j.apmr.2010.08.027
30.
PowellC., CarsonB.P., DowdK.P., & DonnellyA.E. (2016). Simultaneous validation of five activity monitors for use in adult populations, Scandinavian Journal of Medicine & Science in Sports, n/a-n/a. doi:10.1111/sms.12813
RietbergM.B., Van WegenE.E., & KwakkelG. (2010). Measuring fatigue in patients with multiple sclerosis: Reproducibility, responsiveness and concurrent validity of three Dutch self-report questionnaires. Disabil Rehabil, 32(22), 1870–1876. doi:10.3109/09638281003734458
SamaeiA., BakhtiaryA.H., HajihasaniA., FatemiE., & MotaharinezhadF. (2016). Uphill and Downhill Walking in Multiple Sclerosis: A Randomized Controlled Trial. Int J MS Care, 18(1), 34–41. doi:10.7224/1537-2073.2014-072
35.
SunnerhagenK.S., OlverJ., & FranciscoG.E. (2013). Assessing and treating functional impairment in poststroke spasticity. Neurology, 80(3 Suppl 2), S35–44. doi:10.1212/WNL.0b013e3182764aa2
36.
van den BergM., DawesH., WadeD.T., NewmanM., BurridgeJ., IzadiH., & SackleyC.M. (2006). Treadmill training for individuals with multiple sclerosis: A pilot randomised trial. J Neurol Neurosurg Psychiatry, 77(4), 531–533. doi:10.1136/jnnp.2005.064410
