Clinical trial NCT03662555: Effect of Neuromuscular Electrical Stimulation Combined With Blood Flow Restriction on Muscular and Cardiovascular Function
Official title: Effect of Neuromuscular Electrical Stimulation Combined With Varying Degrees of Blood Flow Restriction on Muscular and Cardiovascular Function
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Muscle Weakness
Muscle Atrophy
Lead sponsor: St. Mary's University, Twickenham
Sponsor class: OTHER
First posted: 2018-09-07
Enrollment: 50
Sex: ALL
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: In a multi-arm parallel randomised controlled trial design. The randomisation scheme will be generated via online software (http://www.randomization.com). Participants will be recruited to 6 weeks of training, 3 sessions a week and randomised to one of three groups.

Group 1, participants will undergo NMES and BFR (80% pressure) applied to the quadriceps for 25 min.

Group 2, participants will undergo NMES and BFR (40% pressure) applied to the quadriceps for 25 min.

Group 3, participants will undergo NMES alone (Control) applied to the quadriceps for 25 min.
Primary purpose: TREATMENT

Brief summary: Neuromuscular electrical stimulation (NMES) has recently been combined with blood flow restriction (BFR) in controlled trials and has shown increased muscular strength and size compared with NMES and BFR on their own. However, none have used BFR pressures previously recommended. The first study of my Ph.D. found 40% and 80% BFR pressures to induce acute fatigue and muscle swelling. However, 80% caused higher ratings of pain and perceived exertion. The present study will determine whether NMES combined with either 40% or 80% BFR causes greater structural muscular adaptations and is perceptually easier after 6 weeks of training.

Detailed description: Laboratory testing will take place on 28 separate occasions, 2 familiarisation, 8 testing and 18 intervention sessions. The first session (FAM 1) will serve as a familiarisation trial to the NMES protocol, BFR stimulus and strength testing. It will be conducted 10-14 days prior to the intervention period. The second session (FAM 2) will serve as a second familiarisation trial to the NMES protocol, BFR stimulus and strength testing. This session will take place 7 days prior to the beginning of the intervention period and will serve as a standardised control period prior to the main testing. The third session (PRE) will take place 1 day prior the start of the intervention period and all future sessions will consist of strength, muscle and cardiovascular function outcome measures. The fourth session (MID) will take place the morning following 3 weeks of training. The fifth session (POST1) will take place 48 hours following 6 weeks of training. There will also be post testing sessions after three days (POST2), one week (POST3) and two weeks post intervention (POST4) to assess detraining. Participants will be provided with protein supplementation after every training session. All strength, muscle and hemodynamic measurements will be conducted at St Marys University by Paul Head. Supplements should be avoided for 72 hours prior to experimental measures and throughout the intervention period. All repeated measures will be performed at a similar time of day (± 1 h).

Eligibility criteria: Inclusion Criteria:

* Healthy adults aged between 18 and 45 years old

Exclusion Criteria:

* History of lower extremity surgery, traumatic injuries to the ankle, knee, hip, pelvis and lower back
* Current musculoskeletal condition
* High blood pressure
* Cardiovascular pathology

Primary outcomes:
measure: Quadriceps volume and muscle architecture (3D Ultrasound)
timeFrame: 8 weeks
measure: Knee extension isometric, eccentric, concentric and endurance strength (Cybex)
timeFrame: 8 weeks
Secondary outcomes:
measure: Voluntary activation
timeFrame: 8 weeks
measure: Near-infrared spectroscopy
timeFrame: 8 weeks
measure: Blood pressure
timeFrame: 8 weeks
Other outcomes:
Locations:
Study officials:
References: