Training of lower limb strength in healthy individuals Musculoskeletal Diseases
Conditions
Interventions
Free weight training (barbell squats) or machine training (leg press) was performed over 8 weeks.
1. Randomization will be performed in advance, using a computer-generated random number sequence to
Sponsors
University of Birmingham
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Healthy adult males aged between 18 and 35 years 2. No history of major sports injuries to the spine or lower limb joints, such as severe sprains, fractures, or tendon ruptures 3. No history of lower limb or spine surgery, and no current or recent chronic pain or functional limitations 4. A BMI ranging from 18.5 to 29.9, covering the normal to slightly overweight categories 5. No chronic diseases that could affect study outcomes, such as diabetes, cardiovascular diseases, respiratory conditions, or other systemic illnesses 6. Not taking any medications that could influence the study results, including but not limited to steroids, antihypertensive drugs, or glucocorticoids
Exclusion criteria
Exclusion criteria: 1. History of major lower extremity injury or surgery (e.g., fracture, ligament tear, tendon rupture, etc.) 2. Existing leg pain, swelling, or functional limitation which may affect the safety and effectiveness of resistance training 3. Diagnosis of severe osteoarthritis or osteoporosis 4. Any bone or joint disorders known to limit the movement of the lower extremities 5. History of cardiovascular disease, such as coronary heart disease, heart failure, uncontrolled hypertension, or recent cardiac surgery 6. History of neurological conditions such as stroke, multiple sclerosis, or spinal cord injury 7. Any neurological disorder that may affect muscle control or coordination 8. Severe chronic medical conditions, such as diabetes, kidney disease, or uncontrolled thyroid dysfunction
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The following primary outcome measures will be assessed at baseline and after the 3rd, 4th, and 7th training sessions (within the 8-week intervention period): 1. Knee extensor muscle strength will be measured using an isokinetic dynamometer (Biodex System 3, USA) during maximal voluntary isometric, concentric, and eccentric contractions 2. Maximal isometric force will be measured using an isometric belt squat test with a force sensor (RS, UK) | — |
Secondary
| Measure | Time frame |
|---|---|
| The following secondary outcome measures will be assessed at baseline and after the 3rd, 4th, and 7th training sessions (within the 8-week intervention period): 1. Vertical jump performance, including countermovement jump (CMJ) and squat jump (SJ), will be measured using a force platform system (BTS Bioengineering, Italy). Jump height is calculated using the flight time method. 2. Intermuscular coordination will be measured using wireless surface electromyography (sEMG) systems (BTS Bioengineering, Italy). sEMG signals will be synchronously recorded from eight lower-limb muscles: vastus medialis, vastus lateralis, rectus femoris, tibialis anterior, gluteus maximus, biceps femoris (long head), semitendinosus, and medial gastrocnemius during the performance of countermovement jumps (CMJ) and squat jumps (SJ). Non-negative matrix factorization (NMF) will be applied to the multichannel EMG data to evaluate changes in muscle coordination patterns over time. 3. Vasti muscle activity will be measured using high-density surface electromyography (HDsEMG) with 64-channel (13×5) electrode grids (OT Bioelettronica, Italy) placed over the vastus medialis, vastus lateralis, and rectus femoris muscles. HDsEMG signals will be recorded during multiple contraction tasks including: (1) isometric knee extensions on a Biodex System 3 dynamometer (USA) at MVC, trapezoidal contractions at 10%, 30%, 50%, and 70% MVC, and explosive contractions at 75% MVC for RTD assessment; (2) concentric and eccentric contractions at MVC and submaximal efforts (10% and 50% MVC) using visual template matching; and (3) isometric belt squat tests using a force sensor (RS, UK), followed by 10% and 50% MVC trapezoidal contractions. All submaximal tasks will be performed with real-time visual feedback on an external screen to ensure force tracking accuracy. EMG signals will be analysed using custom MATLAB scripts to extract RMS values, entropy, and spatial activation maps. Motor unit decomposition is conducted | — |
Countries
England, United Kingdom
Contacts
Public ContactDeborah Falla
Outcome results
None listed