Peter is a physiotherapist and lecturer at the Graduate School of Health, Discipline of Physiotherapy at UTS. He graduated with a BSc in Sport and Exercise Science from Auckland University in 2005, a Master of Physiotherapy from Sydney University in 2008 and a PhD in clinical neurophysiology and Neurorehabilitation from Aalborg University and Hammel Neurorehabilitation Centre in 2011. Following his PhD, he volunteered in the Philippines before returning to academia where he conducted post-doctoral research at Neuroscience Research Australia and Hammel Neurorehabilitation Centre. He remains affiliated with Neuroscience Research Australia and Hammel Neurorehabilitation Centre.
Peter's research interests are in neurorehabilitation. His current and previous research is diverse and include training regimes in patients with brain injury, gait rehabilitation and changes in gait in patients with MS and stroke, investigation of muscle properties using ultrasound, functional outcomes following stroke and severe TBI, and non-invasive brain stimulation and peripheral electrical stimulation in patients with brain injury.
Can supervise: YES
Peter's research interests are in neurorehabilitation, motor control and outcomes following brain injury. He has conducted research with patients following stroke, MS and severe/mild TBI. In addition, he has a keen research interest in muscle physiology. His current and previous research areas are diverse and include
- Training regimes in patients with brain injury
- Gait rehabilitation and changes in gait
- Muscle properties using ultrasound
- Functional outcomes following stroke and severe TBI
- Non-invasive brain stimulation and peripheral electrical stimulation
Current and previous teaching areas include Subacute Rehabilitation, Professional Practice and research project supervision.
Faras, TJ, Laporte, MD, Sandoval, R, Najjar, F, Ade, V & Stubbs, P 2019, 'The effect of unilateral blood flow restriction on temporal and spatial gait parameters.', Heliyon, vol. 5, no. 1.View/Download from: UTS OPUS or Publisher's site
Blood flow restriction walking (BFR-W) is becoming more frequently used in aerobic and strength training and it has been proposed that BFR-W can be used in clinical populations. BFR-W may change gait stability yet few studies have assessed gait changes during or following BFR-W. The aim of this study was to assess if spatial-temporal gait parameters change during and following BFR-W. Twenty-four participants completed two walking sessions (>48-hours apart); 1) Unilateral BFR-W applied at the dominant thigh, 2) walking without BFR. In each session participants performed a 5-min warmup, 15-min walking intervention and 10-min active recovery. The warmup and active recovery were performed without BFR on both days. Measurements were attained at baseline, during the intervention and post-intervention using the GAITRite®. Linear mixed models were applied to each measured variable. Fixed factors were timepoint (warmup, intervention, and active recovery), condition (BFR-W and control walking) and condition × timepoint. Random factors were subject and subject × condition. Participants took shorter (3.2-cm (mean difference), CI95%: 0.8-5.6-cm) and wider strides (1.4-cm, CI95%: 0.9-1.9-cm) during BFR-W. For single leg measures, participants took shorter steps (2.8-cm, CI95%: 1.7-4.0-cm) with a faster single support time (7.5-ms, CI95%: 2.9-12.0-ms) on the non-dominant (unoccluded) leg during BFR-W compared to the non-dominant leg during control walking. There were no differences in step length and single support time between the dominant (occluded) leg during BFR-W compared to the dominant leg during control walking. There were no significant changes in velocity, cadence or double support time between BFR-W and control walking (P > 0.05). BFR-W caused small transient changes to several gait parameters. These changes should be considered when using BFR-W in clinical populations.
Kjeldsen, SS, Næss-Schmidt, ET, Hansen, GM, Nielsen, JF & Stubbs, PW 2019, 'Neuromuscular effects of dorsiflexor training with and without blood flow restriction.', Heliyon, vol. 5, no. 8.View/Download from: UTS OPUS or Publisher's site
Blood flow restriction training (BFRT) has been proposed for elderly and clinical populations with weakness. Before being used in these populations it is important to understand the neurological effects of, and subject perceptions to, BFRT. Seventeen healthy subjects were recruited and performed 2 experimental sessions, BFRT and training without blood flow restriction (TR-only), on separate days. Four sets of concentric/eccentric dorsiflexion contractions against theraband resistance were performed. Surface electromyography of the tibialis anterior was recorded during exercise and for the electrophysiological measures. At baseline, immediately-post, 10-min-post and 20-min-post exercise, motor evoked potentials (MEPs) from single pulse transcranial magnetic stimulation (TMS), paired-pulse TMS with interstimulus intervals of 2-ms (SICI) and 15-ms (ICF), and the M-max amplitude were recorded in the resting TA. Following training, subjects provided a numerical rating of the levels of pain, discomfort, fatigue, focus and difficulty during training. Muscle activation was higher in the last 20 contractions during BFRT compared to TR. There was no difference (time × condition interaction) between BFRT and TR for single-pulse MEP, SICI, ICF or M-max amplitude. There was a significant main effect of timepoint for single-pulse MEP and M-max amplitudes with both significantly reduced for 20-min-post exercise. No reductions were observed for SICI and ICF amplitudes. Taken together, BFRT and TR-only were only different during exercise and both regimes induced similar significant reductions in M-Max and MEP-amplitude post-training. Due to the lack of changes in SICI and ICF, it is unlikely that changes occurred in cortical sites related to these pathways. The increased surface electromyography activity in the last 20 contractions, indicate that the training regimes are different and that BFRT possibly induces more fatigue than TR. As such, BFRT could be used as an adjunct to co...
Ade, V, Schalkwijk, D, Psarakis, M, Laporte, MD, Faras, TJ, Sandoval, R, Najjar, F & Stubbs, PW 2018, 'Between session reliability of heel-to-toe progression measurements in the stance phase of gait', PLOS ONE, vol. 13, no. 7.View/Download from: UTS OPUS or Publisher's site
Pedersen, AR, Stubbs, PW & Nielsen, JF 2018, 'Reducing redundant testing using the Functional Independence Measure and Early Functional Abilities scale during rehabilitation in patients with brain injury', BRAIN INJURY, vol. 32, no. 9, pp. 1090-1095.View/Download from: UTS OPUS or Publisher's site
Stubbs, PW, Walsh, LD, D'Souza, A, Heroux, ME, Bolsterlee, B, Gandevia, SC & Herbert, RD 2018, 'History-dependence of muscle slack length following contraction and stretch in the human vastus lateralis', JOURNAL OF PHYSIOLOGY-LONDON, vol. 596, no. 11, pp. 2121-2129.View/Download from: UTS OPUS or Publisher's site
Kothari, M, Stubbs, PW, Figlewski, K, Pedersen, AR, Jensen, J, Baad-Hansen, L, Svensson, P & Nielsen, JF 2017, 'Effect of transcranial direct current stimulation on neuroplasticity in corticomotor pathways of the tongue muscles.', Journal of Oral Rehabilitation, vol. 44, no. 9, pp. 691-701.View/Download from: UTS OPUS or Publisher's site
The aim of this study is to investigate effects of transcranial direct current stimulation (tDCS) on neuroplasticity in corticomotor pathways related to tongue muscles evoked by a training task using the tongue drive system (TDS). Using a crossover design, 13 healthy participants completed two sessions of tDCS while performing 30 min of TDS training. Sessions were spaced at least 2 weeks apart and participants randomly received anodal and sham tDCS stimulation in the first session and the other condition in the second session. Single and paired pulse transcranial magnetic stimulation was used to elicit motor evoked potentials (MEPs) of the tongue at three time-points: before, immediately after and 30 min after training. Participant-based reports of fun, pain, fatigue and motivation, level of difficulty and effort were evaluated on numerical rating scales. There was no consistent significant effect of anodal and sham stimulation on single or paired pulse stimulation MEP amplitude immediately or 30 min after TDS training. Irrespective of tDCS type, training with TDS induced cortical plasticity in terms of increased MEP amplitudes for higher stimulus intensities after 30 min compared with before and immediately after training. Participant-based reports revealed no significant difference between tDCS conditions for level of fun, fatigue, motivation, difficulty and level of effort but a significant increase in pain in the anodal condition, although pain level was low for both conditions. In conclusion, tongue MEP amplitudes appear to be sensitive to training with the tongue using TDS; however, anodal tDCS does not have an impact on training-evoked neuroplasticity of tongue corticomotor pathways.
Kothari, M, Stubbs, PW, Pedersen, AR, Jensen, J & Nielsen, JF 2017, 'Reliability of surface electromyography measurements from the suprahyoid muscle complex.', Journal of Oral Rehabilitation, vol. 44, no. 9, pp. 683-690.View/Download from: UTS OPUS or Publisher's site
Assessment of swallowing musculature using motor evoked potentials (MEPs) can be used to evaluate neural pathways. However, recording of the swallowing musculature is often invasive, uncomfortable and unrealistic in normal clinical practice. To investigate the possibility of using the suprahyoid muscle complex (SMC) using surface electromyography (sEMG) to assess changes to neural pathways by determining the reliability of measurements in healthy participants over days. Seventeen healthy participants were recruited. Measurements were performed twice with one week between sessions. Single-pulse (at 120% and 140% of the resting motor threshold (rMT)) and paired-pulse (2 ms and 15 ms paired pulse) transcranial magnetic stimulation (TMS) were used to elicit MEPs in the SMC which were recorded using sEMG. ≈50% of participants (range: 42-58%; depending on stimulus type/intensity) had significantly different MEP values between day 1 and day 2 for single-pulse and paired-pulse TMS. A large stimulus artefact resulted in MEP responses that could not be assessed in four participants. The assessment of the SMC using sEMG following TMS was poorly reliable for ≈50% of participants. Although using sEMG to assess swallowing musculature function is easier to perform clinically and more comfortable to patients than invasive measures, as the measurement of muscle activity using TMS is unreliable, the use of sEMG for this muscle group is not recommended and requires further research and development.
Næss-Schmidt, ET, Blicher, JU, Eskildsen, SF, Tietze, A, Hansen, B, Stubbs, PW, Jespersen, S, Østergaard, L & Nielsen, JF 2017, 'Microstructural changes in the thalamus after mild traumatic brain injury: A longitudinal diffusion and mean kurtosis tensor MRI study.', Brain Injury, vol. 31, no. 2, pp. 230-236.View/Download from: UTS OPUS or Publisher's site
The primary aim of this study was to assess microstructural changes in the thalamus, hippocampus and corpus callosum with a fast mean kurtosis tensor (MKT) technique, in the acute and sub-acute phase after mTBI. It was hypothesized that MKT would differ between baseline and follow-up in patients. The secondary aim was to relate diffusion measures to symptoms of mTBI.A longitudinal case-control study.Twenty-seven patients with mTBI and 27 age- and gender-matched healthy controls were enrolled in the study. Patients were scanned within 2 weeks and 3 months after mTBI, while the controls were scanned once.MKT decreased significantly (p = 0.02) from baseline to follow-up in the thalamus in patients. Compared to healthy subjects, thalamic MKT values were significantly larger in patients at baseline (p = 0.048). Secondary analysis revealed a significant decrease (p = 0.01) in fractional anisotropy in the splenium of corpus callosum from baseline to follow-up.The current study indicates microstructural changes in the thalamus and corpus callosum from within 14 days to 3 months after mTBI and suggests MKT as a potential biomarker after mTBI.
Næss-Schmidt, ET, Morthorst, M, Pedersen, AR, Nielsen, JF & Stubbs, PW 2017, 'Corticospinal excitability changes following blood flow restriction training of the tibialis anterior: a preliminary study.', Heliyon, vol. 3, no. 1, pp. 1-18.View/Download from: UTS OPUS or Publisher's site
To examine the neural excitability of projections to the tibialis anterior (TA) following blood flow restriction training (BFRT). This is the first study to examine the TA following BFRT.Ten subjects performed each experiment. Experiment one consisted of BFRT at 130 mmHg (BFRT-low). Experiment two consisted of BFRT at 200 mmHg (BFRT-high), training (TR-only) and blood flow restriction at 200 mmHg (BFR-only) performed on separate days. Blood flow restriction was applied to the thigh and training consisted of rapid dorsiflexion contractions against gravity every 10 s for 15-min. The motor evoked potential (MEP) peak-to-peak amplitudes were recorded pre-intervention and 1-, 10-, 20- and 30-min post-intervention and expressed relative to the maximal peak-to-peak M-wave at each time-point.Experiment one revealed no difference in MEP amplitudes for BFRT-low over time (P = 0.09). Experiment two revealed a significant effect of time (P < 0.001), with 1-min post-intervention MEP amplitudes significantly facilitated compared to pre-intervention, but no effect of intervention (P = 0.79) or intervention*time interaction (P = 0.25). Post-hoc power calculations were performed for the intervention*time interaction.Corticospinal excitability of projections to the TA did not change following BFRT-low and corticospinal excitability changes between BFRT-high, BFR-only and TR-only interventions were not different over time. In experiment two, there was a significant main effect of time 1-min post-intervention which was mainly due to the BFRT-high intervention. Post-hoc power calculations revealed that 15 subjects were required for a significant interaction effect 80% of the time however, as the changes in corticospinal excitability were not prolonged, a new dataset of ≥ 15 subjects was not acquired.
Odgaard, L, Johnsen, SP, Stubbs, PW, Pedersen, AR & Nielsen, JF 2017, 'Alternative measures reveal different but low estimates of labour market attachment after severe traumatic brain injury: A nationwide cohort study.', Brain Injury, vol. 31, no. 10, pp. 1298-1306.View/Download from: UTS OPUS or Publisher's site
To explore if the definition of labour market attachment (LMA) changes LMA proportions after severe traumatic brain injury (TBI).Cohort study with 5-year follow-up.Patients aged 18-64 years with severe TBI from 2004 to 2012 (n = 637) and matched controls (n = 2497).LMA was defined in three ways. All definitions included patients working with no government benefits. Definition 2 included patients receiving unemployment benefits (LMA-unemployment benefits). Definition 3 included patients receiving supplemental benefits/services such as patients involved in work-activation schemes (LMA supplementary benefits). First week of return to work (RTW), stable LMA first year after RTW and weekly LMA prevalence were calculated. Patients and controls were compared using multivariable conditional logistic regression.LMA unemployment benefits had similar proportions to LMA with no benefits. These estimates were lower than LMA supplemental benefits where 52% attempted to RTW and 31% achieved stable LMA within 2 years. The maximal LMA prevalence (LMA supplementary benefits) decreased from 33 to 30% from years 2 to 5. Adjusted odds ratios were 0.05 and 0.06 for years 1 and 2, and 0.07 for stable LMA in patients compared to controls.LMA proportions differed depending on the definition. Regardless of definition, LMA proportions following severe TBI were low in Denmark.
Psarakis, M, Greene, D, Moresi, M, Baker, M, Stubbs, P, Brodie, M, Lord, S & Hoang, P 2017, 'Impaired heel to toe progression during gait is related to reduced ankle range of motion in people with Multiple Sclerosis.', Clinical Biomechanics, vol. 49, pp. 96-100.View/Download from: UTS OPUS or Publisher's site
Gait impairment in people with Multiple Sclerosis results from neurological impairment, muscle weakness and reduced range of motion. Restrictions in passive ankle range of motion can result in abnormal heel-to-toe progression (weight transfer) and inefficient gait patterns in people with Multiple Sclerosis. The purpose of this study was to determine the associations between gait impairment, heel-to-toe progression and ankle range of motion in people with Multiple Sclerosis.Twelve participants with Multiple Sclerosis and twelve healthy age-matched participants were assessed. Spatiotemporal parameters of gait and individual footprint data were used to investigate group differences. A pressure sensitive walkway was used to divide each footprint into three phases (contact, mid-stance, propulsive) and calculate the heel-to-toe progression during the stance phase of gait.Compared to healthy controls, people with Multiple Sclerosis spent relatively less time in contact phase (7.8% vs 25.1%) and more time in the mid stance phase of gait (57.3% vs 33.7%). Inter-limb differences were observed in people with Multiple Sclerosis between the affected and non-affected sides for contact (7.8% vs 15.3%) and mid stance (57.3% and 47.1%) phases. Differences in heel-to-toe progression remained significant after adjusting for walking speed and were correlated with walking distance and ankle range of motion.Impaired heel-to-toe progression was related to poor ankle range of motion in people with Multiple Sclerosis. Heel-to-toe progression provided a sensitive measure for assessing gait impairments that were not detectable using standard spatiotemporal gait parameters.
Stubbs, PW, Pedersen, AR & Nielsen, JF 2017, 'Day-to-day features of soleus stretch reflexes in sub-acute stroke patients.', Somatosensory and Motor Research, vol. 34, no. 2, pp. 123-128.View/Download from: UTS OPUS or Publisher's site
The aim of the study was to assess the reliability and variability of stretch reflex magnitude (SRmag) in sub-acute stroke patients. For testing, rapid dorsiflexion stretches were induced 24 h apart in 22 patients and 34 controls. SRmag between sessions in patients and controls was not different and the SRmag on the more-affected side was significantly larger than the less-affected, dominant, and non-dominant sides. The SRmag was consistent between sessions. Therefore, patients were not as variable between sessions as we had hypothesized.
Thom, JM, Diong, J, Stubbs, PW & Herbert, RD 2017, 'Passive elongation of muscle fascicles in human muscles with short and long tendons.', Physiological Reports, vol. 5, no. 23, pp. 1-8.View/Download from: UTS OPUS or Publisher's site
This study tested the hypothesis that the ratio of changes in muscle fascicle and tendon length that occurs with joint movement scales linearly with the ratio of the slack lengths of the muscle fascicles and tendons. We compared the contribution of muscle fascicles to passive muscle-tendon lengthening in muscles with relatively short and long fascicles. Fifteen healthy adults participated in the study. The medial gastrocnemius, tibialis anterior, and brachialis muscle-tendon units were passively lengthened by slowly rotating the ankle or elbow. Change in muscle fascicle length was measured with ultrasonography. Change in muscle-tendon length was calculated from estimated muscle moment arms. Change in tendon length was calculated by subtracting change in fascicle length from change in muscle-tendon length. The median (IQR) contribution of muscle fascicles to passive lengthening of the muscle-tendon unit, measured as the ratio of the change in fascicle length to the change in muscle-tendon unit length, was 0.39 (0.26-0.48) for the medial gastrocnemius, 0.51 (0.29-0.60) for tibialis anterior, and 0.65 (0.49-0.90) for brachialis. Brachialis muscle fascicles contributed to muscle-tendon unit lengthening significantly more than medial gastrocnemius muscle fascicles, but less than would be expected if the fascicle contribution scaled linearly with the ratio of muscle fascicle and tendon slack lengths.
Héroux, ME, Stubbs, PW & Herbert, RD 2016, 'Behavior of human gastrocnemius muscle fascicles during ramped submaximal isometric contractions', Physiological Reports, vol. 4, no. 17.View/Download from: Publisher's site
© 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society. Precise estimates of muscle architecture are necessary to understand and model muscle mechanics. The primary aim of this study was to estimate continuous changes in fascicle length and pennation angle in human gastrocnemius muscles during ramped plantar flexor contractions at two ankle angles. The secondary aim was to determine whether these changes differ between proximal and distal fascicles. Fifteen healthy subjects performed ramped contractions (0–25% MVC) as ultrasound images were recorded from the medial (MG, eight sites) and lateral (LG, six sites) gastrocnemius muscle with the ankle at 90° and 120° (larger angles correspond to shorter muscle lengths). In all subjects, fascicles progressively shortened with increasing torque. MG fascicles shortened 5.8 mm (11.1%) at 90° and 4.5 mm (12.1%) at 120°, whereas LG muscle fascicles shortened 5.1 mm (8.8%) at both ankle angles. MG pennation angle increased 1.4° at 90° and 4.9° at 120°, and LG pennation angle decreased 0.3° at 90° and increased 2.6° at 120°. Muscle architecture changes were similar in proximal and distal fascicles at both ankle angles. This is the first study to describe continuous changes in fascicle length and pennation angle in the human gastrocnemius muscle during ramped isometric contractions. Very similar changes occurred in proximal and distal muscle regions. These findings are relevant to studies modeling active muscle mechanics.
Stubbs, PW & Diong, J 2016, 'The effect of strengthening interventions on strength and physical performance in people with cerebral palsy (PEDro synthesis)', BRITISH JOURNAL OF SPORTS MEDICINE, vol. 50, no. 3, pp. 189-190.View/Download from: Publisher's site
Pedersen, AR, Stubbs, PW & Nielsen, JF 2015, 'Statistical Considerations When Assessing Short Latency Stretch Reflexes in the Human Soleus Muscle', MOTOR CONTROL, vol. 19, no. 4, pp. 253-270.View/Download from: Publisher's site
Stubbs, PW, Pallesen, H, Pedersen, AR & Nielsen, JF 2014, 'Using EFA and FIM rating scales could provide a more complete assessment of patients with acquired brain injury', DISABILITY AND REHABILITATION, vol. 36, no. 26, pp. 2278-2281.View/Download from: Publisher's site
Pedersen, AR, Stubbs, PW & Nielsen, JF 2013, 'Standard Assumptions About the Trial-by-Trial Distribution of Averaged Electromyography Data Could Produce Erroneous Results', MOTOR CONTROL, vol. 17, no. 1, pp. 75-94.View/Download from: Publisher's site
Stubbs, PW, Nielsen, JF, Sinkjaer, T & Mrachacz-Kersting, N 2012, 'Short-latency crossed spinal responses are impaired differently in sub-acute and chronic stroke patients', CLINICAL NEUROPHYSIOLOGY, vol. 123, no. 3, pp. 541-549.View/Download from: Publisher's site
Stubbs, PW, Nielsen, JF, Sinkjaer, T & Mrachacz-Kersting, N 2011, 'CROSSED SPINAL SOLEUS MUSCLE COMMUNICATION DEMONSTRATED BY H-REFLEX CONDITIONING', MUSCLE & NERVE, vol. 43, no. 6, pp. 845-850.View/Download from: Publisher's site
Stubbs, PW, Nielsen, JF, Sinkjaer, T & Mrachacz-Kersting, N 2011, 'Phase Modulation of the Short-Latency Crossed Spinal Response in the Human Soleus Muscle', JOURNAL OF NEUROPHYSIOLOGY, vol. 105, no. 2, pp. 503-511.View/Download from: Publisher's site
Odgaard, L, Harsløf, I & Stubbs, P 2019, 'Return to Work After Severe Traumatic Brain Injury in Diverse Labour Market and Welfare State Contexts' in Harslof, I, Poulsen, I & Larsen, K (eds), New Dynamics of Disability and Rehabilitation: Interdisciplinary Perspectives, Palgrave Macmillan, Singapore, pp. 1-328.
This collection provides a broad coverage of recent changes in medical and vocational rehabilitation in Northern Europe.
Gervasio, S, Stubbs, P & Mrachacz-Kersting, N 2015, 'Chapter 5: Motor control and motor learning' in Jull, G, Moore, A, Falla, D, Lewis, J, McCarthy, C & Sterling, M (eds), Grieve's Modern Musculoskeletal Physiotherapy, Elsevier, pp. 1-625.
Since the third edition of Grieve's Modern Manual Therapy was published in 2005, the original concepts of manipulative therapy have grown to embrace new research-generated knowledge. Expansions in practice have adopted new evidence which include consideration of psychological or social moderators. The original manual therapy or manipulative therapy approaches have transformed into musculoskeletal physiotherapy and this is recognized by the change in title for the new edition - Grieve's Modern Musculoskeletal Physiotherapy.
Grieve's Modern Musculoskeletal Physiotherapy continues to bring together the latest state-of-the-art research, from both clinical practice and the related basic sciences, which is most relevant to practitioners. The topics addressed and the contributing authors reflect the best and most clinically relevant contemporary work within the field of musculoskeletal physiotherapy.
With this as its foundation and a new six-strong editorial team at its helm, the fourth edition now expands its focus from the vertebral column to the entire musculoskeletal system. For the first time both the spine and extremities are covered, capturing the key advances in science and practices relevant to musculoskeletal physiotherapy.
The book is divided into five parts containing multiple sections and chapters. The first part looks at advances in the sciences underpinning musculoskeletal physiotherapy practice. Here there is commentary on topics such as movement, the interaction between pain and motor control as well as neuromuscular adaptations to exercise. Applied anatomical structure is covered in addition to the challenges of lifestyle and ageing. A new section highlights the important area of measurement and presents the scope of current and emerging measurements for investigating central and peripheral aspects relating to pain, function and morphological change. Another section discusses some contemporary research approaches such as quantitative and qualitativ...