Effects of Squat Variations on Quadriceps Muscle Thickness and Strength

Uskudar University42 enrolled

Overview

The study was conducted using a randomized controlled trial design. Participants who met the inclusion criteria were randomly assigned to either the "Classic Squat Group" or the "Heel-Elevated Squat Group." Both groups completed an 8-week strength training program consisting of three sessions per week, following the resistance exercise principles recommended by the American College of Sports Medicine. The main component of the program was the assigned squat variation. Baseline and post-intervention assessments at 8 weeks were performed according to standardized protocols. Exercise sessions were supervised by an experienced physiotherapist to ensure proper technique and minimize injury risk. Training intensity was progressively increased based on participants' adaptation and one-repetition maximum (1-RM) strength levels.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

OTHER

Masking

SINGLE

Enrollment

Conditions

Exercise Physiology Muscle Strength and Oxygenation

Interventions

Participants completed an 8-week supervised bodyweight squat program performed twice weekly, with progressive increases in training volume and intensity. Squats were performed to approximately parallel depth, using a controlled \~2-s eccentric phase followed by maximal intended concentric velocity, with 2-min rest intervals between sets.

Heel-Elevated Squat GroupOTHER

Participants in the Heel-Elevated Squat Group performed all repetitions with both heels supported on rigid 5-cm wedges. Participants completed an 8-week supervised bodyweight squat program performed twice weekly, with progressive increases in training volume and intensity. Squats were performed to approximately parallel depth, using a controlled \~2-s eccentric phase followed by maximal intended concentric velocity, with 2-min rest intervals between sets.

Eligibility

Sex: FEMALEMin age: 18 YearsMax age: 35 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * No musculoskeletal, neurological, or cardiopulmonary conditions that would prevent participation in exercise * Healthy young adults * No regular lower extremity training participation in the last 6 months Exclusion Criteria: * History of surgery or serious injury to the knee, hip, or ankle joints within the past year * Presence of any neurological disorder affecting balance or motor control * Presence of any cardiovascular or pulmonary disease that contraindicates exercise participation

Outcomes

Primary Outcomes

Muscle Strength (Isomed 2000 Isokinetic Dynamometer)

Quadriceps muscle strength was assessed using a Isomed 2000 isokinetic dynamometer, which is considered a gold-standard method for evaluating muscle performance. Isokinetic testing measures maximal torque produced by the muscle throughout the range of motion at a constant angular velocity, providing reliable data on muscle function. Knee extension strength were evaluated.

Time frame: Baseline and 8 weeks post-intervention

Secondary Outcomes

Assessment of Muscle Thickness

Before measurement, participants rested for 20 minutes, and quadriceps muscle thickness was assessed at the midpoint between the anterior superior iliac spine and the superior pole of the patella using B-mode ultrasonography. Anterior thigh muscle thickness was defined as the distance between the superficial fascia of the rectus femoris and the femoral periosteum, representing the combined thickness of the rectus femoris and vastus intermedius.