Abdominal Muscle Activity and Lower Limb Forces When Walking

With Nordic Walking Poles

Valerie Sparkes, Lucy Warren

Katie Whitehouse

Background

• Research into the effects of walking for patients with low back pain has been shown to be beneficial Callaghan et al (1999)

• Abdominal muscles appear to influence the stability of the spine via their connection to the thoracolumbar fascia

Walking and abdominal

• Abdominal muscle activity has been shown to change when patients have LBP

• Theories: (i)changes in muscle activity cause spinal pain (muscle-tension or pain-spasm-pain model)

• or (ii) changes in muscle activity serve to restrict spinal motion (pain adaptation model) Hodges and Moseley (2003)

• Disturbed muscle function seems to be a risk factor for developing LBP Anders et al (2005)

Abdominal muscles

• All trunk muscles play a role on supporting spine

• Internal and external oblique play an equally important role in maintaining spinal stability and trunk rotation Kavcic et al, (2004), Ng et al, (2006).

Internal and external obliques

• Internal and external oblique show relatively constant activity throughout the gait cycle White and McNair (2002).

• IO being most active during the late-stance phase and EO most active at mid-stance Waters and Morris, (1972), Dofferhof and Vink, (1985), Krebs et al, (1992) Callaghan et al (1999)

Forces through lower limb

• effect of supervised NW compared to unsupervised NW or advice to remain active (126 LBP subjects).

• no differences between 8 weeks of supervised or unsupervised NW and advice to remain active

• all groups experienced some improvement in pain and disability during the intervention period Hartvigsen et al (2010)

Forces through lower limb

• Walking with NW poles provides 30-50% load reduction to joints of the lower limb Geyer (2005) and INWF (2009)

Effects of walking poles on lower extremitygait mechanics

• All walking with poles conditions significantly increased walking speed, stride length, and stance time compared with the no poles condition.

• decrease in average vertical GRF walking with poles

• decrease in vertical (compressive) knee joint reaction force

• (13 subjects) Willson et al (2001)

Forces when walking with Nordic walking poles

• No-significant reductions in knee-joint loading when comparing walking with NW poles with normal walking,

Schwameder and Ring (2006), Jöllenbeck et al (2006) and Grüneberg et al (2006)

Aim

• There is no evidence to date on the effect of walking with

Nordic Walking Poles on abdominal muscle activity• Conflicting evidence regarding the effect on lower limb

forces

Aim: To determine effect of walking with Nordic

Walking Poles on:

• Internal & External oblique muscle activity • Lower limb vertical ground reaction forces

Nordic Walker® Trainer CR

Method• Crossover experimental study

• 15 (10F, 5M) Healthy subjects, • 21.06 (± 0.88) years• All provide informed consent

• Subjects underwent training period from International Nordic Walking Trainer,

Karen Ingram

Outcome measures

• Surface EMG • Maximum Voluntary

contractions of IO & EO (% MVC)

• Kistler force platform Vertical Ground reaction forces (Newtons)

Method

• Study conducted in Research Centre of Clinical Kinaesiology

• Split group into 2. Group 1 were tested walking without poles first then with poles

• Group 2 were tested walking with poles first and without poles

• Practice time walking with and without NW poles in the Lab placing right foot on force plate

Method

• Walked at a self selected speed along eight metre walkway during both conditions

• Three sets of data were collected for each condition

• The mean muscle activities of IO & EO over the last five seconds of each condition were measured.

• Data processing:MATLAB 71• Data analysis (SPSS) Version

16• Paired t test as data normally

distributed.

Results: Muscle activity and forces

• Significant Increases IO & EO walking with poles p=0.002

• Internal oblique No poles 31.94 (39.9)With Poles 53.05 (40.6)

• External oblique No poles 46.45 (30.9) With Poles 87.93 (60.5)

• Significant Increase in VGRF walking with poles p=0.008 (11.13%)

No poles 871.6 (237.00) Newtons

With Poles 968.33 (210.8) Newtons

Summary

Increased IO & EOactivity may be of valuefor some LBP patientswhere increases in muscleactivity are the objectives oftreatment.

EO largest values whenwalking with poles ?due to rotationalcomponent of walkingpattern or arm activity

• VGRF increased? due to novice

walkers lack of practice

• subjects concentration on hitting force platform

Limitations & further research

• Small numbers of subjects

• Novice walkers• Laboratory data

collection

• Collect speed of gait data

• Forces through ankle/knee/hip

• Erector spinae muscles as well as abdominals

• Walking further distance

http://www.nordicwalking.co.uk/