Electrical Muscle Stimulation (EMS) uses controlled electrical impulses to prompt muscle contraction, offering a method for muscle training and rehabilitation. Historically, this technology was used in physical therapy settings to prevent muscle atrophy in injured patients.
The question of whether EMS can effectively contribute to glute development has moved the technology into the fitness world, where it is now explored to enhance muscle strength and toning.
How Electrical Muscle Stimulation Activates Muscles
EMS devices send a controlled electrical current through electrodes placed on the skin directly over the targeted muscle group, such as the gluteal muscles. This electrical impulse bypasses the central nervous system, which normally initiates a voluntary muscle contraction. Instead, the external signal directly causes motor neurons to fire, leading to an involuntary muscle contraction that mimics exercise.
The resulting contraction intensity is determined by the device’s settings, including frequency and amplitude, which must be carefully calibrated. Unlike voluntary contractions, which typically recruit smaller, slow-twitch muscle fibers (Type I) first, EMS often recruits the larger, fast-twitch muscle fibers (Type II) at higher intensities. This ability to preferentially activate Type II fibers, responsible for muscle size and explosive strength, is a theoretical advantage of EMS training. The involuntary contraction allows for deep muscle activation that can be challenging to achieve through conscious effort alone.
Scientific Findings on Gluteal Muscle Strength and Toning
Research suggests that EMS can contribute to both strength gains and changes in muscle size (hypertrophy) in the glutes, particularly when the stimulation is intense and consistent. Studies on whole-body EMS (WB-EMS) have demonstrated an increase in muscle mass and strength parameters across multiple muscle groups, including the glutes. This is especially true in sedentary individuals who may struggle with proper glute activation during traditional exercise.
The immediate benefit observed is an improvement in muscle function and a more efficient contraction pattern, stemming from neuromuscular adaptation. For healthy individuals, strength gains from EMS alone may primarily be due to changes in the nervous system’s ability to recruit muscle fibers rather than significant muscle size increase in the short term. The most pronounced effects on muscle size and strength require a high-intensity, frequent schedule, often three times a week for several weeks.
EMS’s effectiveness is highly dependent on the parameters used and the individual’s starting fitness level. While EMS can increase muscle mass by approximately 1% and improve muscle function by 10–15% after five to six weeks, these results are complementary to, rather than a replacement for, traditional resistance training. EMS can help activate deeper gluteus maximus muscle fibers that are typically hard to reach with voluntary exercises.
Integrating EMS with Traditional Training
EMS is most effective when integrated as a supplement to a comprehensive fitness routine, rather than being used in isolation. When combined with voluntary exercises like squats, lunges, or hip thrusts, EMS acts as a “workout multiplier” by intensifying the muscle contraction beyond conscious control. This concurrent use, where stimulation occurs while performing a movement, boosts muscle activation and recruits a greater number of muscle fibers.
For the glutes, using EMS during movements like glute bridges or kickbacks helps target the muscle group more precisely and ensure full engagement. This combined approach is beneficial for individuals dealing with “gluteal amnesia,” where the muscles are underactive due to prolonged sitting. EMS helps re-establish the neural connection, teaching the brain how to fire the glutes more effectively during conventional training.
This synergistic training approach is superior for maximizing strength and hypertrophy compared to either EMS or conventional exercise alone. The intensity of a voluntary glute exercise is limited by the load, while EMS adds a powerful, targeted contraction independent of the external weight. Using EMS after a workout is also common, as increased blood flow and muscle contractions can aid in post-exercise recovery and reduce soreness.
Important Safety Considerations and Limitations
Before beginning an EMS routine, safety guidelines must be strictly followed.
Contraindications
EMS is contraindicated for individuals with certain medical conditions. This includes those with pacemakers, defibrillators, or other implanted electronic devices, as the electrical signals can interfere with their function. People who are pregnant or have a history of epilepsy, severe skin conditions in the application area, or recent surgical procedures should also avoid using EMS unless medically supervised.
Proper Usage
The safety of EMS depends on correct usage, including proper electrode placement and intensity management. Incorrect placement can lead to ineffective stimulation or discomfort. Starting with too high an intensity can cause muscle fatigue, strain, or soreness. Users should always begin with a low setting and gradually increase the intensity to a level that causes a strong but comfortable contraction.
Limitations
Users must be aware that EMS devices available for home use are not all regulated equally; seeking certified devices that meet established safety standards is advisable. Overuse is a common mistake, as muscles require recovery time just as they do after traditional weight training. Limiting sessions to two to three times per week is generally recommended. While EMS contributes to strength, it does not provide the cardiovascular or systemic health benefits associated with full-body resistance training and exercise.