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Trial registered on ANZCTR


Registration number
ACTRN12616000023459
Ethics application status
Approved
Date submitted
4/01/2016
Date registered
14/01/2016
Date last updated
3/03/2017
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effects of two neuromuscular training programs on running biomechanics with load carriage: a randomized controlled trial

Scientific title
In a cohort of healthy runners, does a biomechanically informed neuromuscular training program, do better than a generic strength training program, in improving self-determined load carriage running velocity and biomechanics, lower limb strength and power?
Secondary ID [1] 287937 0
Nil Known
Universal Trial Number (UTN)
U1111-1176-6844
Trial acronym
CARNET = CArriage Running NEuromuscular Training
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Running biomechanics 296817 0
Lower limb strength and power 296818 0
Condition category
Condition code
Musculoskeletal 297048 297048 0 0
Normal musculoskeletal and cartilage development and function
Neurological 297443 297443 0 0
Studies of the normal brain and nervous system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The principle of this training program is that key neuromuscular requirements of load carriage running are targeted by specific neuromuscular exercises. All training is administered in small group sessions by trained Exercise and Rehabilitation therapists. Two one hour training programs will be delivered to the therapists by the principal investigator to standardize the training program. This program will involve three training sessions per week for 6 weeks (total 18 sessions), and will involve single leg (SL) hopping (at 2.2 Hz), countermovement jumps (CMJ), and hip flexor cable pull. Each session will last approximately 45 minutes. For the plyometric component (hop and CMJ), intensity will be varied using a weighted vest. For the hopping, intensity will also be varied by increasing the hopping frequency to a maximal of 3.0Hz. Another key focus of this training group is that non-optimal lower limb alignment are corrected using a mixture of visual, auditory and verbal cues. In order to maintain peak power application for the CMJ and hip flexor pull, a cluster set method will be used. For the CMJ and SL hopping, a starting weight of 5% body weight will be used, with a 5% weight increment per week, until a maximum load of 20% body weight is achieved. A maximal mass of 20% BM will be added, as previous studies have demonstrated a reduction in peak power with heavier mass. For the hip flexor pull, a starting weight of ~80% of one repetition maximum (1RM) will be used at week 1 progressing to ~ 88% of 1RM at week 6. For the hip flexor pull, a 1RM load will be adjusted by a weekly increase of a factor of 2.5% to account for weekly increase in strength. The SL hopping will involve 2 to 4 sets of 20 second hopping. The CMJ and hip flexor pull will involve 5 to 10 sets of a cluster of 2 to 3 reps, to maintain peak power. Adherence to the exercises will be ensured by the onsite trainers, using patient record sheets.
Intervention code [1] 293287 0
Other interventions
Comparator / control treatment
The principle governing this training program is that participants perform progressively heavy isotonic resistance training, at intensities from ~80% of 1RM at week 1 progressing to ~ 88% of 1RM at week 6. All training is administered in small group sessions by trained Exercise and Rehabilitation therapists. Two one hour training programs will be delivered to the therapists by the principal investigator to standardize the training program.This program will involve three training sessions per week for 6 weeks (total 18 sessions). Inter-set rest duration of three to five minutes will be provided. Each session will last approximately 45 minutes. Exercises will include isotonic unilateral leg press, unilateral calf press, and Russian lunge. These exercises were selected as they represented generic lower limb exercises used in current load carriage training studies. For all exercises, a 1RM load will be adjusted by a weekly increase of a factor of 2.5% to account for weekly increases in strength. All exercises will be sub-maximal in intensity (i.e. repetition failure will not occur). Adherence to the exercises will be ensured by the onsite trainers, using patient record sheets.
Control group
Active

Outcomes
Primary outcome [1] 296648 0
Self selected overground running speed with a 20% body weight load, using a backpack filled with sandbags to achieve the target weight, across a biomechanics labaratory, via three dimensional motion analysis using force plates (AMTI, Watertown, MA) and 18 camera motion capture system (Vicon T-series, Oxford Metrics, UK) .
Timepoint [1] 296648 0
Baseline (pre intervention) and week 7 (post intervention)
Primary outcome [2] 296649 0
Running biomechanics (Joint work of hip, knee, ankle) via three dimensional motion analysis using force plates (AMTI, Watertown, MA) and 18 camera motion capture system (Vicon T-series, Oxford Metrics, UK) .

Composite measure
Timepoint [2] 296649 0
Baseline (pre intervention) and week 7 (post intervention)
Primary outcome [3] 297000 0
Running biomechanics (Joint power of hip,knee,ankle) via three dimensional motion analysis using force plates (AMTI, Watertown, MA) and 18 camera motion capture system (Vicon T-series, Oxford Metrics, UK) .
Composite measure

Timepoint [3] 297000 0
Baseline (pre intervention) and week 7 (post intervention)
Secondary outcome [1] 318986 0
Countermovement jump peak power via three dimensional motion analysis using force plates (AMTI, Watertown, MA) and 18 camera motion capture system (Vicon T-series, Oxford Metrics, UK) .

Timepoint [1] 318986 0
Baseline (pre intervention)
Mid trial (3rd week)
Week 7 (post intervention)
Secondary outcome [2] 318987 0
Isokinetic strength test (60 degree/second) of Knee extensors (90 degree flexion to 0 degree) using HUMAC NORM dynamometer (Computer Sports Medicine Inc., Stoughton, MA)


Timepoint [2] 318987 0
Baseline (pre intervention) and week 7 (post intervention)
Secondary outcome [3] 319821 0
Running biomechanics (Joint angle of hip,knee,ankle) via via three dimensional motion analysis using force plates (AMTI, Watertown, MA) and 18 camera motion capture system (Vicon T-series, Oxford Metrics, UK) .
Composite measure
Timepoint [3] 319821 0
Baseline (pre intervention) and week 7 (post intervention)
Secondary outcome [4] 319822 0
Isokinetic strength test (60 degree/second) of ankles extensors (5 degre dorsiflexion to 30 degree plantarflexion) using HUMAC NORM dynamometer (Computer Sports Medicine Inc., Stoughton, MA)
Timepoint [4] 319822 0
Baseline (pre intervention) and week 7 (post intervention)
Secondary outcome [5] 319823 0
Squat jump peak power via three dimensional motion analysis using force plates (AMTI, Watertown, MA) and 18 camera motion capture system (Vicon T-series, Oxford Metrics, UK) .
Timepoint [5] 319823 0
Baseline (pre intervention)
Mid trial (3rd week)
Week 7 (post intervention)
Secondary outcome [6] 319824 0
Hopping leg stiffness via three dimensional motion analysis using force plates (AMTI, Watertown, MA) and 18 camera motion capture system (Vicon T-series, Oxford Metrics, UK) .
Timepoint [6] 319824 0
Baseline (pre intervention)
Mid trial (3rd week)
Week 7 (post intervention)
Secondary outcome [7] 319827 0
Self selected overground running speed with no external load, across a biomechanics labaratory, via three dimensional motion analysis using force plates (AMTI, Watertown, MA) and 18 camera motion capture system (Vicon T-series, Oxford Metrics, UK) .
Timepoint [7] 319827 0
Baseline (pre intervention) and week 7 (post intervention)

Eligibility
Key inclusion criteria
Participants between 18 and 60 years old who are in good general health, and are currently running or participating in running-related sports with an accumulated total distance of 45 minutes/week, will be recruited.
Minimum age
18 Years
Maximum age
60 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
1. Presence of any disorders that could affect their gait and load carrying ability.
2. Medical conditions that preclude heavy resistance training and strenuous running.
3. Presence of a training-loss running related injury within the last 3 months.
4. Current running related pain (except blisters or muscle soreness)}
5. Lower limb surgery within the past 12 months.
6. Females who are pregnant.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Sealed opaque envelopes
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Permuted stratified block randomization using computer generated sequence.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
This study was powered on the effects of a core stability program on changes to hopping leg stiffness. Sample size was planned based on a two way, repeated measures ANOVA, using the Hotelling-Lawley Trace to test for an intervention by time interaction. Previous studies on leg stiffness reported a standard deviation of 3600 N/m, and a correlation between repeated measures of 0.80. For a desired power of 0.80, and a Type 1 error rate of 0.05, we need to enrol 24 participants to detect a between group mean difference of 3000N/m. In order to account for a 20% dropout over the 6 weeks intervention period, we will enrol 30 participants. All statistical analysis will be performed in R software within RStudio (Version 0.98.1062, RStudio, Inc.). Descriptive statistics (mean and standard deviation) will be calculated for baseline demographics of participants. Between groups difference in baseline demographics will be calculated using t-test or non-parametric test where appropriate. Analysis will be based on an intention-to-treat (ITT) using the multiple imputation method. A repeated measures linear mixed model with time, group, and their interaction as fixed effects, and participants clustered within groups as random effects will be used to analyse our discrete dependent variables. For the linear mixed model, significance will be set at a = 0.05. Statistical testing between group and within group mechanical wave form data (kinematics, kinetics) will be analysed using Statistical Parametric Mapping (SPM). Statistical significance will be inferred using Random Field Theory (RFT), with appropriate Bonferroni correction applied to retain a family-wise error rate of a = 0.05. SPM will be performed using spm1d package (v0.3) (www.spm1d.org), installed in Python 2.7, and implemented in Enthought Canopy 1.5.4 (Enthought Inc., Austin, USA).

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
WA

Funding & Sponsors
Funding source category [1] 292417 0
University
Name [1] 292417 0
Curtin University Internal funding
Address [1] 292417 0
Kent Street, Bentley, WA 6102
Country [1] 292417 0
Australia
Primary sponsor type
Individual
Name
A/Prof Kevin Netto
Address
Curtin University, Kent Street, Bentley, WA 6102
Country
Australia
Secondary sponsor category [1] 291141 0
None
Name [1] 291141 0
NA
Address [1] 291141 0
NA
Country [1] 291141 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293905 0
Curtin University Human Research Ethics Committee
Ethics committee address [1] 293905 0
Kent street, Bentley, WA 6102
Ethics committee country [1] 293905 0
Australia
Date submitted for ethics approval [1] 293905 0
29/10/2014
Approval date [1] 293905 0
30/07/2015
Ethics approval number [1] 293905 0
RD-41-14

Summary
Brief summary
Background: Ultra-endurance and adventure racing are increasingly becoming popular with recreational and elite athletes. These athletes routinely carry some form of external loads, to transport various equipment for survival, navigation and sustenance. It has been well reported that load carriage impairs gait performance, with subsequent training studies conducted to identify if gait performance improved. However, most of these training studies were not of a randomized, controlled trials design, and they were largely conducted within the military setting. More importantly, exercise selections within current studies have not been based on known neuromuscular demands involved in load carriage gait patterns. Previous studies on load carriage in running have identified potential adaptive and mal-adaptive biomechanical alterations when load is imposed on running. Adaptive mechanical alterations are changes whose functions are to needed to sustain running speed, enhance postural control, support an increased weight and absorb shock. Mal-adaptive alterations are changes which could heighten the risk of incurring injuries, and reduce gait performance. It is hypothesized that a neuromuscular training that is targeted to known neuromuscular demands of load carriage running would compare better than a generic strength training program in improving load carriage running mechanics.
Methods: This study will be a two-arm, parallel randomized controlled trial with single assessor blinding. 30 healthy runners, aged 18 to 60 years, will be enrolled. The total duration of this study is 8 weeks, broken up into two phases. In the first phase, participants will undergo a common two weeks familiarization training sessions. They will undergo a pre and post biomechanics and strength testing assessment. A permuted block randomization procedure will be used as participants will be stratified based on gender (male/female). Allocation will be concealed using sealed-opaque envelopes. After baseline assessments, participants will be randomized into either a targeted or a general neuromuscular training program. Both programs will involve three supervised sessions per week for six weeks. A mid assessment will be conducted during the 3rd week with regards to maximal jumps and hops.
Statistical analysis: Baseline demographic variables will be compared using parametric and non-parametric tests, where appropriate. Descriptive statistics (mean and standard deviation) will be calculated. A linear mixed model will be used to identify between group and within group by time changes in discrete dependent variables. Statistical Parametric Mapping will be used to identify between and within group by time changes in time-continuous dependent variables. Statistical inference will be made at a family wise error rate of a = 0.05.
Trial website
Trial related presentations / publications
Submissions are pending and will be filled up when accepted
Public notes

Contacts
Principal investigator
Name 61678 0
Mr Bernard Liew
Address 61678 0
School of Physiotherapy and Exercise Sciences, Curtin University, GPO Box U1987, Perth, WA 6845
Country 61678 0
Australia
Phone 61678 0
+618 9266 3689
Fax 61678 0
+618 9266 3699
Email 61678 0
b.liew@postgrad.curtin.edu.au
Contact person for public queries
Name 61679 0
A/Prof Kevin Netto
Address 61679 0
School of Physiotherapy and Exercise Sciences, Curtin University, GPO Box U1987, Perth, WA 6845
Country 61679 0
Australia
Phone 61679 0
+618 9266 3689
Fax 61679 0
+618 9266 3699
Email 61679 0
Kevin.Netto@curtin.edu.au
Contact person for scientific queries
Name 61680 0
A/Prof Kevin Netto
Address 61680 0
School of Physiotherapy and Exercise Sciences, Curtin University, GPO Box U1987, Perth, WA 6845
Country 61680 0
Australia
Phone 61680 0
+618 9266 3689
Fax 61680 0
+618 9266 3699
Email 61680 0
Kevin.Netto@curtin.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary