For actor Karen Fukuhara, the physical requirements of her role as Kimiko Miyashiro in the Prime Video series The Boys are more than just a costume change. To convincingly portray a character defined by explosive speed, agility, and superhuman strength, Fukuhara has leaned into a rigorous strength-training regimen that mirrors the intensity of the assassin she plays on screen.
While the result is a seamless performance of “wolf-like” movements and high-impact stunts, the path to this level of fitness was not immediate. Fukuhara’s journey into weightlifting began with a common hurdle: gym intimidation. After college, an initial attempt to get into fitness failed to stick, largely due to the overwhelming nature of gym etiquette and the confusion of navigating complex machinery.
The turning point came during her preparation for the film Suicide Squad. By working with a professional trainer, Fukuhara shifted her perspective from simply exercising to understanding the mechanics of her own body. This transition from “working hard” to “training smarter” provided the foundation for the confidence she now brings to the weight room, allowing her to treat the gym as a dedicated space for mental clarity and physical preparation.
The Strategy Behind the Strength
Understanding how ‘The Boys’ actor Karen Fukuhara gets strong requires a look at her specific programming, which prioritizes compound movements and functional strength. Her approach follows a strategic hierarchy: beginning with the heaviest lifts while her energy levels are highest, then transitioning into lighter weights and unilateral movements to address imbalances.
Fukuhara typically adheres to a volume of four sets of 10 repetitions per exercise. However, when working with maximum loads, she pushes the muscle to failure—a technique used in hypertrophy training to stimulate muscle growth and increase overall power output.
A central component of her routine is the focus on the posterior chain—the muscles running along the back of the body, including the glutes, hamstrings, and erector spinae. Because Fukuhara identifies as “quad dominant,” meaning her quadriceps tend to take over during lower-body movements, she utilizes specific exercises to isolate the glutes. What we have is critical for the stability required during the low-to-the-ground stunt work essential to Kimiko’s fighting style.
The Workout Breakdown
Fukuhara’s routine is a blend of strength and corrective exercise, designed to offset the physical tolls of a modern professional lifestyle and the specific demands of action choreography.
| Exercise | Primary Target | Purpose/Benefit |
|---|---|---|
| Barbell Glute Bridges | Glutes/Hips | Lower-body power for stunts |
| Seated Cable Rows | Upper Back/Rhomboids | Counteracting “laptop posture” |
| Landmine Deadlifts | Posterior Chain | Back-safe heavy lifting |
| Single-Leg Deficit Bridges | Glutes/Stability | Hip mobility and balance |
| “Arm Blast” Circuit | Biceps/Triceps/Delts | Upper body definition |
Prioritizing Joint Health and Posture
From a medical perspective, Fukuhara’s choice of the landmine deadlift over the traditional barbell deadlift is a significant detail. Traditional deadlifts, while effective, place substantial shear force on the lumbar spine if form wavers. After experiencing a back injury with the traditional version, Fukuhara transitioned to the landmine variation. This adjustment alters the center of gravity and allows for a more natural arc of movement, reducing the risk of lower-back strain while still allowing for high-intensity loading.
Fukuhara integrates seated cable rows to combat the effects of sedentary technology use. The tendency to hunch over laptops and phones leads to protracted shoulders and a rounded upper back. By targeting the muscles of the mid-back, she offsets this forward movement, improving her overall posture and shoulder health.
The routine concludes with a high-volume “arm blast”—a superset of bicep curls, tricep kickbacks, and rear delt flies—and weighted straight-leg raises for core stability. This combination ensures that while the heavy compound movements build the foundation, the accessory work provides the stability and definition necessary for the physical demands of her career.
The Role of Recovery and Gear
Strength is not built solely in the gym, but during the recovery phase. Fukuhara utilizes electrolytes to maintain hydration and mineral balance, which is essential for muscle contraction and preventing cramps during high-intensity sessions. Her equipment choices, including padded gloves, suggest a focus on grip stability and skin protection during heavy pulls, allowing her to focus on the muscle contraction rather than the discomfort of the barbell.
For those looking to replicate this level of strength, the overarching lesson in Fukuhara’s approach is the value of professional guidance. The shift from feeling overwhelmed to feeling confident was predicated on education—learning exactly what each exercise does for the body rather than following a generic template.
Disclaimer: This content is for informational purposes only and does not constitute medical advice. Always consult with a healthcare provider or a certified fitness professional before beginning a new exercise regimen, especially if you have a history of back injuries.
As The Boys continues to expand its narrative on Prime Video, the physical evolution of its cast remains a key part of the show’s visceral appeal. Future updates on the series’ production and the actors’ preparations for upcoming seasons are typically shared via official studio press releases and cast interviews.
Do you have a favorite strength-training modification that has helped you avoid injury? Share your experience in the comments below.
