None listed
Conditions
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.
Interventions
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
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.
Sponsors
A/Prof Kevin Netto
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Prevention
Masking
Blinded (masking used) (Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to 60 Years
Healthy volunteers
Yes
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.
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.
Outcome results
None listed