The single leg hip thrust (SLHT) is a targeted resistance exercise designed to maximize the strength and development of the posterior chain musculature. This movement involves placing the upper back on an elevated surface and driving the hips upward using one leg. The primary purpose of the SLHT is to build a strong foundation in the glutes and hamstrings, which are the main engines for hip extension. By focusing the effort onto a single limb, the exercise introduces unilateral training, promoting balanced development and stability.
The Primary Driving Muscles
The engine of the single leg hip thrust is the Gluteus Maximus, the largest and most powerful muscle in the human body. Its primary action is hip extension, which drives the hips toward the ceiling during the thrust phase. The architecture of the exercise, particularly the horizontal loading and short range of motion at the top, is highly effective at recruiting the Gluteus Maximus, often leading to high levels of muscle activation compared to other common lower body movements.
Working synergistically with the glutes are the Hamstrings, a group of three muscles that run down the back of the thigh. These muscles assist in extending the hip, particularly in the bottom half of the movement. Since the SLHT is performed with a bent knee, the hamstrings are placed in a shortened position, which helps shift the muscular emphasis slightly more toward the glutes. The unilateral nature of the SLHT increases the demand on the hamstrings for both force production and stability compared to a traditional two-legged hip thrust.
Supporting and Stabilizing Musculature
The single-leg variation significantly increases the demand on surrounding muscles to maintain balance and proper alignment. The Gluteus Medius and Gluteus Minimus, located on the side of the hip, are recruited intensely to stabilize the pelvis. Their main function is to prevent the non-working side of the hip from dropping or rotating, an action known as pelvic stability. This increased stabilization requirement helps address muscle imbalances between the left and right sides of the body.
The Core Musculature, including the Rectus Abdominis and Obliques, plays a substantial role in maintaining a neutral spine throughout the movement. These muscles engage isometrically to prevent the lower back from hyperextending as the hips reach full extension. A rigid core ensures that the force generated by the glutes and hamstrings is directed efficiently into the hip joint. The muscles of the lower back, specifically the spinal erectors, are also continuously active to keep the torso stable against the bench.
Maximizing Muscle Activation Through Proper Form
Achieving maximum muscle engagement in the single leg hip thrust depends heavily on precise execution. Foot placement is important; the working foot should be positioned so the shin is vertical when the hips are fully extended. If the foot is too far forward, it increases the range of motion at the knee, shifting work toward the hamstrings and away from the Gluteus Maximus. Placing the foot too close may conversely engage the quadriceps more than intended.
A primary cue for maximizing glute activation is to drive through the heel of the working foot, which minimizes quadriceps involvement and directs force through the posterior chain. Maintaining a slight chin tuck throughout the movement helps prevent the neck from overextending and reinforces core engagement. This cue ensures the spine remains relatively neutral, which is necessary for effective core stabilization.
The movement should focus on achieving full hip extension without allowing the lower back to arch excessively. At the peak of the thrust, the shoulders, hips, and knee of the working leg should form a straight line, representing the point of maximal glute contraction. Slowly controlling the descent back to the starting position under tension is necessary, as this eccentric phase contributes significantly to muscle development and strength gains.