The bodyweight squat (BW squat) is a foundational movement involving lowering the hips from a standing position and then standing back up, using only one’s own mass as resistance. This exercise targets the major lower body muscle groups, including the quadriceps, hamstrings, and glutes. Whether this simple movement can build muscle (hypertrophy) depends on an individual’s current fitness level and training history. For those new to resistance training, the BW squat is an effective stimulus for muscle growth.
The Science of Muscle Hypertrophy
Muscle growth is driven by three distinct mechanisms that signal muscle fibers to increase in size. The primary driver of hypertrophy is mechanical tension, which is the physical load placed upon the muscle tissue during exercise. This tension disrupts the muscle structure and activates molecular pathways that promote the synthesis of new muscle proteins. The two secondary mechanisms are metabolic stress (the “pump” sensation) and muscle damage (microscopic tears). While all three contribute, an effective muscle-building program must first ensure sufficient mechanical tension to initiate the growth response.
Bodyweight Squats as a Hypertrophy Stimulus
Bodyweight squats are an excellent hypertrophy stimulus for beginners because the load (the person’s own body mass) represents a novel and challenging amount of mechanical tension. For detrained individuals, this relative intensity is high enough to trigger the necessary molecular signaling for muscle protein synthesis and growth. Studies focusing on sedentary individuals show that progressive bodyweight training can produce increases in muscle size comparable to those achieved with heavy barbell squats.
However, as strength increases, the absolute mechanical tension provided by the BW squat quickly becomes insufficient to drive new growth. To compensate for the lack of heavy external resistance, the squat must be manipulated to maximize metabolic stress and time under tension. This involves performing a high volume of repetitions, often exceeding 20 or 30 per set, to near muscular failure. High-repetition sets create a significant build-up of metabolites, which drives the metabolic stress component of muscle growth.
Applying Progressive Overload Without Weights
For advanced trainees, the BW squat requires systematic progressive overload to continue building muscle. This means increasing the challenge without adding external weights, achieved through modifications to the exercise itself. One method is unilateral training, which shifts the entire body mass onto a single leg, such as in a Bulgarian split squat or a pistol squat. This instantly and substantially increases the relative mechanical tension experienced by the working leg.
Another strategy is to manipulate the exercise tempo to increase the time under tension, which amplifies both mechanical tension and metabolic stress. This can be done using slow eccentric phases, where the lowering portion of the squat takes a controlled count of three to five seconds. Performing an isometric hold at the bottom of the squat for several seconds can overload the muscles at their deepest position. Increasing the range of motion by standing on elevated surfaces is another way to increase the work required.