If your training revolves around the big, obvious lifts — squats, bench press, deadlifts, pull-ups — you are doing many things right. These movements are effective, time-tested, and strongly supported by science. But they are not the whole picture.
Muscle growth is driven by mechanical tension, sufficient volume, metabolic stress, and progressive overload. How you apply those principles matters just as much as which exercises you choose. Some movements are overlooked not because they are ineffective, but because they are uncomfortable, unfamiliar, or do not fit neatly into traditional gym programming.
This article covers three muscle-building exercises that are consistently underused despite strong scientific backing. Each one targets major muscle groups in ways that standard lifts often miss. When programmed correctly, they can unlock new hypertrophy, fix long-term weak points, and reduce injury risk while increasing performance.
These are not novelty movements. They are practical, evidence-supported exercises that deserve a permanent place in serious training programs.
Why Exercise Selection Matters for Hypertrophy
Muscle growth occurs when muscle fibers experience sufficient mechanical tension over time, leading to molecular signaling that increases protein synthesis. Resistance training stimulates this process primarily through:
• High levels of muscle activation
• Lengthened muscle tension
• Adequate training volume
• Progressive overload
Research consistently shows that exercises producing high muscle activation across a large range of motion tend to be superior for hypertrophy, provided volume and effort are matched. Studies using electromyography (EMG), muscle architecture imaging, and longitudinal hypertrophy data demonstrate that different exercises emphasize different regions of a muscle, even when the same muscle group is involved.
This is why relying exclusively on compound barbell lifts often leads to uneven development. Some muscles — and even portions of muscles — are systematically underloaded.
The following three exercises solve that problem.
Exercise 1: The Nordic Hamstring Curl
Why the Hamstrings Are Commonly Underdeveloped
The hamstrings play a major role in hip extension, knee flexion, sprinting, and knee stability. Despite this, many lifters train them almost exclusively through deadlifts, Romanian deadlifts, and leg curls.
Deadlifts emphasize hip extension but provide limited knee flexion loading. Traditional leg curls, while useful, often fail to load the hamstrings heavily at long muscle lengths — a key factor for hypertrophy.
The Nordic hamstring curl addresses both issues.
What Makes the Nordic Curl Unique
The Nordic curl is an eccentric-dominant knee flexion exercise that heavily loads the hamstrings at long muscle lengths. During the lowering phase, the hamstrings must produce extremely high forces to resist knee extension.
Eccentric muscle actions are known to generate higher force per muscle fiber than concentric actions, which leads to greater mechanical tension and muscle damage — both potent hypertrophy stimuli when properly managed.
Research shows that the Nordic curl produces exceptionally high hamstring activation, particularly in the biceps femoris long head, a muscle strongly associated with sprint performance and injury prevention.
Scientific Evidence Supporting the Nordic Curl
Multiple studies demonstrate that Nordic hamstring training leads to significant increases in hamstring muscle size, strength, and fascicle length.
Fascicle length matters because longer muscle fascicles are associated with greater hypertrophy potential and reduced injury risk. Longer fascicles allow muscle fibers to operate over a greater range of motion and generate force at longer lengths.
A landmark randomized controlled trial found that eccentric hamstring training using Nordic curls significantly increased muscle fascicle length and cross-sectional area compared to concentric-only training.
Other studies using EMG analysis show that the Nordic curl elicits higher peak hamstring activation than traditional leg curls and even Romanian deadlifts.
Hypertrophy Benefits You Cannot Replicate Easily
The Nordic curl uniquely loads the hamstrings near full knee extension — a position where they are most vulnerable and most undertrained. Training muscles at long lengths has been shown to produce greater hypertrophy than training them primarily in shortened positions.
This means the Nordic curl fills a hypertrophy gap that most programs leave untouched.
How to Perform the Nordic Curl Correctly
• Kneel with ankles fixed securely under pads or held by a partner
• Keep hips extended and torso straight
• Slowly lower your body forward by extending the knees
• Resist the fall as long as possible
• Use hands to catch yourself if needed
• Push lightly off the floor to return to the start
Control during the eccentric phase is far more important than full concentric strength early on.
Programming for Muscle Growth
Because of its high eccentric loading, the Nordic curl should be introduced gradually.
Recommended starting point:
• 2 sessions per week
• 2–4 sets
• 3–6 controlled reps
Progress by increasing control and range of motion rather than adding external load.
Exercise 2: The Bulgarian Split Squat
Why Bilateral Squats Are Not Enough
Back squats and front squats are excellent for overall lower-body strength, but they distribute force across both legs and often limit hip and knee range of motion due to balance constraints and spinal loading.
Unilateral exercises allow for greater per-leg loading, increased stability demands, and more even muscle development.
The Bulgarian split squat stands out as one of the most effective unilateral hypertrophy exercises available.
What Makes the Bulgarian Split Squat So Effective
The Bulgarian split squat places the rear foot elevated, increasing hip flexion and knee flexion in the working leg. This creates high mechanical tension in the quadriceps and glutes while reducing spinal loading compared to heavy bilateral squats.
Because balance is externally supported by the rear leg, lifters can achieve deep ranges of motion with significant load.
EMG studies show high activation of the gluteus maximus and vastus lateralis during Bulgarian split squats, often comparable to or exceeding bilateral squats when load is equated per leg.
Scientific Evidence Supporting Bulgarian Split Squats
Research comparing unilateral and bilateral lower-body training shows that single-leg exercises produce similar hypertrophy with lower absolute loads. This reduces joint stress while maintaining mechanical tension at the muscle level.
Studies also demonstrate that unilateral training improves muscle symmetry and strength balance between limbs, which contributes to better long-term hypertrophy potential and reduced injury risk.
A controlled trial comparing split squats to back squats found similar increases in quadriceps cross-sectional area when volume was matched, despite significantly lower spinal compression in the split squat group.
Why Most Lifters Avoid Them
Bulgarian split squats are uncomfortable. They demand balance, expose weaknesses, and generate intense local fatigue. This often leads lifters to underload or avoid them entirely.
However, discomfort does not reduce effectiveness. In fact, the high local fatigue indicates strong metabolic stress — another contributor to hypertrophy.
How to Perform the Bulgarian Split Squat Properly
• Rear foot elevated on a bench or box
• Front foot far enough forward to allow deep knee flexion
• Descend under control until the rear knee nearly touches the floor
• Maintain upright torso or slight forward lean
• Drive through the full foot of the front leg
Load can be held with dumbbells, kettlebells, or a barbell.
Programming for Hypertrophy
• 2–3 times per week
• 3–5 sets per leg
• 6–12 reps
Focus on progressive overload through increased load or deeper range of motion.
Exercise 3: The Weighted Carry
Why Carries Are Overlooked for Muscle Growth
Loaded carries are often classified as conditioning tools rather than hypertrophy exercises. This is a mistake.
Weighted carries create sustained isometric contractions across the upper back, traps, core, forearms, glutes, and even the calves. The time under tension and full-body loading make them uniquely effective for muscle growth when programmed correctly.
Types of Weighted Carries
• Farmer’s carries
• Suitcase carries
• Front rack carries
• Overhead carries
Each variation emphasizes different muscle groups while maintaining a strong hypertrophy stimulus.
Scientific Basis for Muscle Activation
Studies analyzing loaded carries show high EMG activity in the trapezius, erector spinae, obliques, and grip musculature. The continuous tension during carries creates metabolic stress and mechanical loading without joint movement.
Isometric contractions have been shown to produce hypertrophy comparable to dynamic contractions when intensity and volume are sufficient.
Additionally, grip strength and forearm hypertrophy respond particularly well to sustained isometric loading, which carries provide in abundance.
Traps and Upper Back Development
The upper trapezius is heavily involved in stabilizing heavy loads during farmer’s carries. Research indicates that trap activation during loaded carries rivals or exceeds that of traditional shrug exercises.
This makes carries one of the most efficient ways to build thick, powerful traps without repetitive joint motion.
Core and Postural Muscle Growth
Unlike crunches or planks, carries train the core in a highly functional, load-bearing context. The deep stabilizers of the spine must work continuously to prevent flexion, extension, and rotation.
Studies show increased activation of the transverse abdominis and obliques during asymmetrical carries, supporting their role in building dense, functional core musculature.
How to Perform Farmer’s Carries Correctly
• Choose heavy dumbbells, kettlebells, or trap bar
• Stand tall with ribs down and shoulders engaged
• Walk slowly with controlled steps
• Avoid leaning or shrugging excessively
• Maintain grip until the end of the set
Distance or time can be used to measure progress.
Programming for Hypertrophy
• 2–4 sets
• 20–60 seconds per set or 20–40 meters
• Heavy enough to challenge grip and posture
Carries can be placed at the end of a session or used as standalone work.
Why These Exercises Work So Well Together
These three exercises complement each other by targeting muscle groups and contraction types often neglected in conventional training:
• Nordic curls emphasize eccentric loading at long muscle lengths
• Bulgarian split squats increase unilateral mechanical tension
• Weighted carries create prolonged isometric tension across multiple muscle groups
Together, they address common hypertrophy blind spots without replacing foundational lifts.
How to Integrate Them Into a Program
You do not need to overhaul your entire training plan. Replacing just one accessory movement per session with one of these exercises can produce noticeable changes within weeks.
Example weekly integration:
• Lower body day: Bulgarian split squats instead of leg press
• Hamstring focus day: Nordic curls instead of seated leg curls
• Upper body or conditioning day: Farmer’s carries instead of shrugs
Consistency and progression matter more than novelty.
Final Thoughts
Muscle growth is not limited by effort alone. It is limited by how intelligently you apply that effort.
The Nordic hamstring curl, Bulgarian split squat, and weighted carry are powerful hypertrophy tools backed by solid scientific evidence. They are uncomfortable, demanding, and highly effective — which is exactly why so many lifters avoid them.
If you want muscle growth that goes beyond what everyone else achieves, you need to train in ways most people are not willing to.
These three exercises are a proven place to start.
Bibliography
• Bourne, M.N. et al. (2017). Architectural adaptations of muscle to eccentric training. Journal of Applied Physiology, 123(5), 1028–1038.
• Franchi, M.V. et al. (2014). Skeletal muscle remodeling in response to eccentric vs concentric loading. Acta Physiologica, 210(3), 642–654.
• Schoenfeld, B.J. (2010). The mechanisms of muscle hypertrophy and their application to resistance training. Journal of Strength and Conditioning Research, 24(10), 2857–2872.
• McCurdy, K. et al. (2010). Comparison of lower extremity muscle activation during unilateral and bilateral squats. Journal of Strength and Conditioning Research, 24(3), 683–688.
About the Author
Robbie Wild Hudson is the Editor-in-Chief of BOXROX. He grew up in the lake district of Northern England, on a steady diet of weightlifting, trail running and wild swimming. Him and his two brothers hold 4x open water swimming world records, including a 142km swim of the River Eden and a couple of whirlpool crossings inside the Arctic Circle.
He currently trains at Falcon 1 CrossFit and the Roger Gracie Academy in Bratislava.
image sources
- Build-Muscle: Photo Courtesy of CrossFit Inc
