Clinical trial NCT07025395: "CORE Training for Musculoskeletal Health: A Study on Adaptive Exercise Protocols"
Official title: Development and Implementation of a Core Training Protocol: Effects on Muscle Activation, Hypertrophy, Balance, and Quality of Life in Recreationally Active Adults
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Neuromuscular Adaptations Through Core Training: Effects on Muscle Hypertrophy, Balance, and Functional Performance
Keywords: Core Training, Neuromuscular Adaptations, Muscle Hypertrophy, EMG, Biomechanics, Balance, Ultrasound, Functional Performance, SWLS
Lead sponsor: Aristotle University Of Thessaloniki
Sponsor class: OTHER
First posted: 2025-06-17
Enrollment: 40
Sex: ALL
Minimum age (years): 25
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: This study employs a parallel-group design with randomized allocation. Participants are divided into an experimental group undergoing an eight-week core training protocol and a control group following a standardized core-related routine. The interventional group receives structured progressive stability, strength, and power-focused exercises, while the control group engages in general core activation without targeted neuromuscular training. Pre- and post-intervention assessments evaluate neuromuscular function, balance, biomechanical efficiency, and life satisfaction.
Primary purpose: BASIC_SCIENCE

Brief summary: This study aims to evaluate the effects of an adaptive core training protocol that integrates core stability, core strength, and high-intensity core power exercises on muscle activation, hypertrophy, balance, and quality of life. Forty recreationally active adults with a minimum of two years of consistent training experience will participate. The structured intervention will span multiple weeks and utilize electromyography (EMG), ultrasound imaging, and validated questionnaires to assess neuromuscular and functional adaptations.

Detailed description: Extended Detailed Description - Part 1: Study Rationale \& Objective Introduction \& Background Core stability represents a foundational component of human movement, underpinning postural control, balance, and kinetic force transmission across the musculoskeletal system. Extensive literature supports the role of the core as both a stabilizer and force conduit, engaging deep and superficial muscle systems through task-specific motor patterns \[Akuthota \& Nadler, McGill, Kolar et al.\]. These systems operate synergistically to enhance spinal alignment, movement efficiency, and functional integrity.

In contemporary health science, core training is no longer confined to elite athletic preparation but has become a critical public health strategy aimed at reducing sedentary dysfunctions, enhancing spinal resilience, and preventing lower back disorders. Modern core protocols integrate trunk bracing, diaphragmatic activation, and dynamic control of movement across all planes of motion.

Study Aim This study aims to develop, implement, and evaluate an eight-week progressive core training protocol that combines elements of stability, strength, and high-intensity power training, addressing both neuromuscular and psychosocial outcomes in healthy recreationally active adults.

Part 2: Study Design, Participants \& Protocol Overview Study Design The research adopts a randomized, controlled interventional design with two parallel arms: an experimental group undergoing a structured eight-week core training program, and a control group following a minimal standardized routine. The study is registered through ClinicalTrials.gov and conducted at the Neuromechanics Laboratory of the Aristotle University of Thessaloniki (Serres Campus).

Participant Criteria

Forty (n=40) recreationally active adults aged 25-35 will be recruited. Eligibility requires:

* ≥2 years of regular non-competitive physical activity (≥3x/week, ≥1 hour/session)
* No history of musculoskeletal, cardiovascular, or neurological pathology
* No prior engagement in structured core-focused training (e.g., CrossFit, Pilates)
* Commitment to attend both baseline and post-intervention assessments Randomization \& Consent Participants will undergo a screening interview and provide written informed consent. Upon qualification, randomization will allocate them into experimental or control groups. Only experimental group participants will receive detailed protocol orientation post-allocation to prevent expectancy bias.

Core Training Program Structure

The intervention consists of:

* Warm-up Phase (\~6 min): Functional mobility drills such as suitcase walk, dumbbell overhead walk, knee push-ups, and T-rotations
* Main Program (\~30-32 min): 8 structured triads, each including:
* 1 Core Stability Exercise
* 1 Core Strength Exercise
* 1 High-Intensity Core Power Exercise
* All performed for 45 sec each, with progressive rest (1:00 to 2:00 min)
* Cool-down Phase (\~5 min): Flexibility \& mobility-focused stretches (e.g., Scorpion, Child's Pose, Cat Camel) This structure adheres to kinetic chain progression principles-starting with motor control, advancing to strength, and culminating in power expression.

Part 3: Measurements, Tools \& Expected Outcomes Evaluation Timeline \& Setting Both groups will undergo baseline and post-intervention assessments at the Neuromechanics Laboratory of the Department of Physical Education and Sport Science (Aristotle University of Thessaloniki, Serres). Testing sessions will be standardized, and pre-assessment warm-ups will be conducted to ensure safe performance.

Instrumentation \& Metrics

The following validated devices and tools will be employed:

* Force Plate Analysis: A 3D Kistler dynamometer (Winterthur, Switzerland) with MARS software will measure ground reaction forces during medicine ball slams and postural balance testing.
* EMG Recording: Surface electromyography (Biopac Systems Inc., USA) will assess neuromuscular activity in rectus abdominis (RA), external oblique (EO), and iliocostalis lumborum (IL) muscles. Data will be recorded at 1024 Hz via a TEL100 M transmitter, filtered between 10-500 Hz.
* Ultrasound Imaging: An Aloka ProSound SSD 3500 SV system (Tokyo, Japan) will measure resting thickness of transverse abdominis (TrA), internal oblique (IO), and multifidus (LM) muscles using a 13 MHz, 6 cm transducer.
* Video Motion Capture: A PTZOptics Move 4K camera will record high-definition kinematic data, with angular velocity analysis performed using Kinovea software (v0.9.5).
* Anthropometry: Body height and weight will be obtained using a Seca 220e stadiometer (Hamburg, Germany).
* Psychometric Evaluation: The Satisfaction With Life Scale (SWLS) will quantify subjective well-being before and after the intervention.

Expected Physiological Outcomes

* Force Application: Improved medicine ball slam output in the experimental group will indicate increased trunk-generated power.
* Muscle Activation \& Efficiency: EMG activity is expected to increase post-intervention, reflecting improved recruitment and neural drive.
* Balance \& Stability: Enhanced postural control and reduced sway in static and dynamic conditions are anticipated due to neuromuscular refinement.
* Kinematic Precision: Increases in joint angular velocities and smoother segmental coordination will reflect better kinetic chain integration.

Structural \& Functional Adaptations

* Deep-Core Hypertrophy: Ultrasound is expected to detect measurable gains in the TrA, IO, and LM, reinforcing spinal alignment and endurance.
* Neuromuscular Synchronization: Enhanced intermuscular coordination will contribute to energy-efficient movement patterns and dynamic control.
* Movement Confidence: Improvements in SWLS scores will reflect greater physical self-efficacy and quality of life Part 4: Broader Implications, Public Health Impact \& Applicability Public Health Relevance Low back pain, poor postural endurance, and sedentary-related dysfunctions remain leading contributors to global disability and occupational strain. Despite a growing emphasis on preventive health strategies, few structured interventions have effectively bridged the gap between elite-level training and scalable, accessible protocols for the general population. The current study directly addresses this gap by offering a feasible, evidence-based solution that integrates key neuromuscular principles into a practical framework for recreational fitness.

Structured core training, when applied correctly, reinforces spinal stability, postural integrity, and movement efficiency, all of which are essential for long-term musculoskeletal health. Moreover, by incorporating validated psychometric tools such as the SWLS, this protocol examines not only physical, but also mental and emotional well-being, aligning with holistic health paradigms in modern preventive medicine.

Scalability \& Real-World Applicability The intervention's modular structure, progressive rest intervals, and tiered intensities allow it to be scalable across different fitness levels-from novice exercisers to well-conditioned individuals. Its reliance on bodyweight and minimal equipment (e.g., dumbbells, medicine balls) makes it ideal for implementation in gyms, rehabilitation settings, or even at-home fitness programs under guided supervision.

Furthermore, the structured triad format-transitioning from stability to power-serves as a valuable educational model for trainers, physiotherapists, and health professionals seeking to design comprehensive and adaptable core training systems.

Contribution to Scientific Knowledge

By measuring multiple domains (activation, hypertrophy, biomechanics, balance, well-being), this study contributes multidimensional insight into core training's efficacy. The methodology adheres to recent theoretical frameworks regarding:

* Motor control theory (task-specific adaptation of trunk stabilizers)
* Force-velocity relationships (sequencing of training stimuli)
* Sensorimotor integration (balance and coordination outcomes)
* Psychosocial enhancement through physical competence Findings from this trial will provide a foundation for larger-scale applications, including intervention design in older adults, occupational wellness programs, and injury prevention curricula in non-professional sport communities.

Conclusion This study stands at the intersection of physiology, biomechanics, and public health. It proposes that carefully designed, progressively loaded core training protocols have the power to enhance not only neuromuscular performance, but also long-term physical well-being and life satisfaction. With its interdisciplinary scope and real-world alignment, the study aims to enrich both the scientific literature and the functional experiences of everyday movers.

Eligibility criteria: Inclusion Criteria:

* Participants for this study will be healthy, physically active adults between the ages of 25 and 35, engaging in regular recreational exercise or non-competitive sports activities. For the purpose of this study, the term "recreational exercise" was defined as physical activity engaged in a minimum of three times per week for a duration of at least one hour in each training session. A list of suitable activities is provided below, including but not limited to: aerobics, dance, folkloric dance, and swimming. A variety of outdoor activities and adventure sports are available, including orienteering, surfing, snowboarding, and caving. Racket games encompass a variety of sports, including tennis, paddle tennis, badminton, and squash. The participants were permitted to engage in a range of activities, including but not limited to mountain biking, mountain climbing, athletics, bowling, horseback riding, skateboarding, swimming, and hiking. Additionally, any other forms of exercise that the investigators deemed appropriate were permitted. In order to qualify for participation, an individual must have been continuously enrolled in the relevant programs for a minimum period of two years. Inclusion is based on criteria ensuring suitability for core training interventions and reducing confounding variables related to prior structured stability training. Eligible participants must be in optimal health, demonstrating no recent musculoskeletal injuries or pre-existing conditions that could limit full range of motion or prevent engagement in high-intensity exercise protocols. They must also commit to attending both baseline and final assessments and adhere to the structured 215 eight-week intervention timeline to maintain data integrity

Exclusion Criteria:

* Exclusion criteria include individuals diagnosed with musculoskeletal impairments that restrict functional movement or prevent core-specific engagement. Additionally, those with cardiovascular or metabolic conditions that contraindicate high-intensity exercise are excluded from participation. To maintain study validity, individuals already engaged in structured core training programs-such as Pilates, CrossFit, calisthenics, or athletes following systematic strength and stability regimens-will also be excluded to prevent prior training effects from influencing study outcomes.

Primary outcomes:
measure: Electromyographic (EMG) Muscle Activation During Medicine Ball Overhead Slam
timeFrame: Baseline (Week 0) and Post-Intervention (Week 8)
Secondary outcomes:
measure: Ultrasound-Based Core Muscle Hypertrophy Assessment
timeFrame: Baseline (Week 0) and Post-Intervention (Week 8)
measure: Balance & Postural Stability Evaluation (Force Plate Analysis)
timeFrame: Baseline (Week 0) and Post-Intervention (Week 8)
Other outcomes:
measure: Kinematic Angular Velocity Analysis (Motion Capture)
timeFrame: Baseline (Week 0) and Post-Intervention (Week 8)
measure: Psychometric Evaluation of Life Satisfaction (SWLS)
timeFrame: Baseline (Week 0) and Post-Intervention (Week 8)
Locations:
city: Serres
country: Greece
facility: Aristotle University of Thessaloniki, Serres Campus - Neuromechanics Laboratory
state: Central Makedonia
Study officials:
affiliation: Aristotle University of Thessaloniki, Greece
name: Ioannis Tsartsapakis, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References: