Jacob deGrom’s rise to the top of Major League Baseball isn’t explained by a 100 mph fastball or a devastating slider alone. It is the product of a meticulously engineered training philosophy that places core strength and flexibility at its center. While many pitchers chase velocity through heavy lifting or endless long toss, deGrom has built his body to withstand the extreme forces of pitching while maximizing energy transfer from the ground through his hips, core, and arm. His approach offers a blueprint for sustainable power, allowing him to dominate even while navigating minor injuries and a demanding workload.

The Foundation of deGrom’s Dominance: Core Stability

Core strength in pitching extends far beyond visible abdominal muscles. For a pitcher, the core is the central link in the kinetic chain—the series of coordinated movements that generate throwing velocity and accuracy. Research from the American Sports Medicine Institute has demonstrated that a stable core enables pitchers to decelerate the trunk after release, reducing stress on the shoulder and elbow (ASMI). deGrom’s training emphasizes this concept heavily, treating core stability as the non-negotiable foundation of every rep.

Anatomy of a Powerful Pitch: The Role of the Core

When deGrom strides toward home plate, his core must resist excessive rotation while simultaneously generating torque. The rectus abdominis, obliques, transverse abdominis, and multifidus all work in concert. A weak core creates energy leaks: the hips may rotate before the trunk is ready, causing the arm to drag or the elbow to drop. deGrom avoids this by building a rigid yet responsive midsection. His mechanics show a textbook sequence—hips lead, trunk follows, arm lags—that only functions with exceptional core control. The deep stabilizers like the transverse abdominis fire reflexively milliseconds before the movement begins, locking the spine in a neutral position. This pre-activation is trained through specific bracing drills.

Core Exercises That Drive deGrom’s Velocity

deGrom’s core program is not about endless crunches. Instead, he focuses on anti-rotation, anti-extension, and rotational power exercises—each chosen to mimic the demands of the pitching motion.

Plank Variations

Standard planks, side planks, and bear crawls form the foundation. deGrom holds side planks with his top foot forward to create a more challenging lever. He often adds leg lifts and band pulls to force his obliques to stabilize under load. These exercises teach the core to resist unwanted motion—critical during the landing phase when forces can exceed eight times body weight. He also performs high plank to low plank transitions to challenge shoulder stability alongside core endurance.

Rotational Work

Russian twists are a staple, but deGrom performs them with controlled tempo and a medicine ball for extra resistance. He also does cable rotations and woodchoppers, targeting the same rotational muscles used to accelerate the trunk. The key is eccentric control: after the explosive twist, he slowly returns to the starting position, building strength through the full range of motion. This mimics the deceleration demands of pitching. Additionally, standing single-arm cable chops work the obliques in a transverse plane while demanding hip stability—a direct carryover to the pitching delivery.

According to Driveline Baseball’s research on core training, rotational exercises that involve a braced core and external load produce the highest transfer to on-field velocity (Driveline). deGrom’s program aligns with this evidence, integrating both heavy-load resistance and explosive movements.

Anti-Extension and Anti-Lateral Flexion Drills

To strengthen the anterior core without aggravating the lower back, deGrom uses dead bugs with a foam roller under the lumbar spine. This forces the core to maintain a neutral pelvis while the arms and legs move independently. He also performs Pallof presses against a cable, a classic anti-rotation exercise that builds stiffness in the obliques and deep transversus. These movements teach the core to stay braced when the trunk is challenged from multiple directions, replicating the chaos of a pitch.

The Role of Breath and Intra-Abdominal Pressure

Core stability is not just muscular; it also depends on intra-abdominal pressure (IAP). deGrom practices coordinated breathing patterns during his lifts—exhaling during exertion, inhaling during eccentric phases—to pressurize the torso. This IAP provides a rigid cylinder for the spine, reducing shear forces. Functional breathing drills, such as 360-degree breathing lying on the ground, are part of his daily warm-up. By optimizing breath mechanics, he creates a more reliable foundation for explosive movement.

Flexibility: The Unsung Hero of Longevity

Core strength would be useless without the flexibility to access extreme joint positions. Pitchers must forcibly externally rotate the shoulder beyond 170 degrees while maintaining a forward trunk tilt. deGrom’s flexibility routine allows him to reach these positions without tissue breakdown. More importantly, mobility ensures that the joints can express power through their full range of motion, preventing compensatory patterns that lead to injury.

Shoulder and Hip Mobility Demands

The throwing shoulder requires both mobility and stability. deGrom’s internal and external rotation range are exceptional, but he earns it through daily mobility work. Similarly, hip mobility—especially internal rotation of the drive leg and external rotation of the landing leg—enables the pelvic tilt that powers the delivery. A study in the Journal of Orthopaedic & Sports Physical Therapy found that pitchers with greater hip range of motion had lower rates of shoulder and elbow injuries (JOSPT). deGrom specifically targets the posterior hip capsule and the deep external rotators, which become tight from the repeated stress of the stride.

deGrom’s Dynamic Flexibility Routine

Before every bullpen or start, deGrom performs a series of dynamic stretches. He avoids static stretching before throwing; instead, he uses leg swings, hip circles, and arm circles to increase blood flow and neural activation. Key drills include:

  • Inchworms with shoulder rolls – to mobilize the spine and shoulders while engaging the core. He holds the bottom position for a deep stretch in the hamstrings and lower back, then rolls the shoulders individually.
  • World’s greatest stretch – a lunge with a torso rotation that opens the hips, thoracic spine, and shoulders simultaneously. He emphasizes a slow, deep rotation holding each side for two breaths.
  • Band-distracted shoulder rotations – using a resistance band around a fixed point to create a gentle distraction while moving the arm through a pitching arc. This opens up the glenohumeral joint without impingement.
  • Hip flexor lunges with overhead reach – to address the tightness that often develops from constant throwing. Reaching overhead while in a deep lunge stretches the hip flexors and latissimus dorsi in one fluid motion.
  • Thoracic spine windmills on foam roller – lying on a foam roller along the spine, he moves his arms in a windmill pattern to improve rotation in the mid-back.

He also uses a lacrosse ball to release trigger points in the hip rotators, glutes, and upper back. This combination of dynamic stretching and self-myofascial release keeps his joints loose and responsive, allowing him to repeat his mechanics inning after inning.

Static Stretching and Recovery

While deGrom avoids static stretching before throwing, he does incorporate longer holds after training or on off days. Key static stretches include the Figure-4 stretch for the piriformis, the lying hamstring stretch with a strap, and a doorway stretch for the pectorals. These target areas that tighten from the repeated overhead position. The National Strength and Conditioning Association (NSCA) recommends static stretching post-workout to restore muscle length and reduce stiffness (NSCA). deGrom follows this principle, using stretching as a recovery tool rather than a warm-up.

Integrating Strength and Flexibility: deGrom’s Weekly Plan

To sustain 100 mph pitches inning after inning, deGrom cannot focus on core or flexibility in isolation. His training week is carefully periodized across the season.

Off-Season vs In-Season Adjustments

During the off-season, deGrom performs heavy core and hip work four times per week, often paired with lower-body strength training (deadlifts, split squats, banded hip thrusts). Flexibility work is done after every lifting session and separately on active recovery days. His off-season mobility sessions are longer—often 30–40 minutes—targeting every joint from the ankles to the cervical spine. As spring training approaches, the load shifts: he reduces strength volume and increases plyometric and reactive core exercises (medicine ball throws, rotational jumps). In-season, he performs maintenance core and mobility work three times per week, emphasizing recovery and injury prevention. The volume is scaled down but intensity remains high to maintain the adaptations built in the off-season.

One of his most notable in-season habits is a 15-minute pre-throw mobility circuit that precedes every catch session. This warm-up includes core bracing drills like dead bugs with a foam roller under the lower back to maintain a neutral spine, followed by dynamic stretches for the hips, shoulders, and back. By keeping the core engaged and the hips mobile, he primes his body to repeat efficient mechanics even late in games.

Sample Microcycle

A typical in-season week might look like this:

  • Day 1 (Start day): 15-minute dynamic warm-up (mobility + core activation), pre-throw band work, then full bullpen. Post-start: 20-minute static stretching and foam rolling.
  • Day 2 (Recovery): Light movement: walking, dynamic range-of-motion drills, compression boots, and gentle lacrosse ball work. No core or strength training.
  • Day 3 (Strength): Lower-body focus: deadlifts, split squats, banded walks, plus core anti-rotation and rotation exercises. Post-lift: 15-minute flexibility routine targeting hips and thoracic spine.
  • Day 4 (Active recovery): Light catch or long toss, followed by 30-minute yoga flow emphasizing deep breathing and hip openers.
  • Day 5 (Strength): Upper-body and core: pull-ups, rows, shoulder extensions, plus pallof presses and side planks. Post-lift: lacrosse ball self-massage and static stretching.
  • Day 6 (Pre-game): Light warm-up: dynamic flexibility, band work, and short bullpen prep. Core activation only.
  • Day 7 (Game day or travel): Repeat Day 1 if starting; otherwise light core and mobility work as needed.

Injury Prevention Through Core and Mobility Work

deGrom has had his share of setbacks—elbow and shoulder issues have sidelined him at times. Yet his training philosophy has helped him return to elite performance quicker than many peers. Why? Because his core and flexibility work reduces the compensatory movements that lead to overuse injuries.

When the core fatigues, a pitcher may start to collapse into the landing leg or rotate too early, placing extra load on the ulnar collateral ligament (UCL). By maintaining core endurance and hip mobility, deGrom preserves the proper mechanics that protect his arm. A systematic review in Sports Health highlighted that core neuromuscular training reduces shoulder and elbow injury risk in overhead athletes (Sports Health). deGrom’s approach embodies this principle.

Additionally, his emphasis on flexibility in the hips and thoracic spine reduces the need for excessive shoulder motion. When the hips and mid-back lack rotation, the shoulder compensates by rotating further—a common pathway to labral or rotator cuff problems. deGrom’s daily mobility targets these exact regions. He also uses regular movement screens, such as the Functional Movement Screen (FMS), to identify asymmetries before they become injuries. By addressing deficits early, he maintains the body’s ability to produce force safely.

Lessons for Pitchers at Every Level

Aspiring pitchers often emulate deGrom’s mechanics or try to throw harder, but they neglect the foundational work that makes it possible. His training teaches several key lessons:

  • Core first, velocity later: Building a stable midsection allows the arm to react rather than create force. A well-trained core decelerates the trunk and reduces stress on the arm.
  • Dynamic flexibility over static stretching: Movement preparation matters more than holding a stretch. Warm up with active, sport-specific patterns that signal the nervous system.
  • Consistency over intensity: deGrom does his core and mobility work year-round, scaling volume not effort. Even on light days, he maintains a baseline.
  • Address weaknesses early: He uses regular assessments (like the FMS) to guide his programming. Don’t wait for pain to correct imbalances.
  • Recovery is training: He prioritizes sleep, nutrition, and active recovery to let his adaptations take hold. Mobility work after strength sessions is just as important as the lifts themselves.
  • Breathe to brace: Functional breathing isn’t optional—it’s the hidden variable in core stability. Practice diaphragmatic breathing during exercises to build intra-abdominal pressure.

Whether you are a high school pitcher or a college competitor, integrating core stability and flexibility into every training session will reduce your injury risk and improve your performance. You don’t need a $10 million training facility—just consistency and smart programming. Start with the basics: dead bugs, planks, Pallof presses, and the world’s greatest stretch. Progress to rotational medicine ball work and dynamic mobility flows. Over time, the cumulative effect will transform your delivery.

Jacob deGrom’s career illustrates the power of a balanced training approach. By making core strength and flexibility the foundation of his regimen, he has not only dominated on the mound but also extended his prime years. For any pitcher looking to reach the next level, the blueprint is clear: stabilize the trunk, mobilize the joints, and never skip the details.