Is full range of motion always better for muscle growth based on current research?

Not always. While initial meta-analyses suggested a slight benefit for full range of motion, more nuanced analysis shows that partial range of motion performed at longer average muscle lengths can lead to similar or even more hypertrophy compared to full range of motion. Shortened partials, however, typically result in worse hypertrophy.

What is the 'specificity principle' in relation to range of motion for strength gains?

The specificity principle states that you get better at what you train. For range of motion, this means training through a full range of motion improves full range of motion strength, and partial range of motion training improves partial range of motion strength. However, full range of motion training tends to have better carryover to partial range of motion performance than vice versa.

Do biceps and triceps benefit from long muscle length training, or are they exceptions?

Existing research, though limited, suggests that biceps and triceps do benefit from long muscle length training, predominantly at more distal sites. While some studies showed no significant difference, nominal trends and regional hypertrophy patterns align with findings in other muscle groups, suggesting it's a generalizable principle.

Does long muscle length training increase muscle size by adding sarcomeres in series (sarcomereogenesis)?

There is currently no strong evidence in humans to support sarcomereogenesis as the primary mechanism. While some animal studies and stretching research show it, direct studies on resistance training and long muscle lengths haven't established this. Recent human research indicates observed increases in fascicle length are largely due to lengthening of existing sarcomeres, not adding new ones.

Is the hypertrophy benefit of long muscle length training only a short-term phenomenon?

The long-term effects are unknown as studies typically last only a few months. However, there's no compelling reason to believe it's purely a short-term novelty effect. Given the consistent findings over shorter durations, it's reasonable to assume a lasting benefit. The concept of 'novelty' in training is generally not as well-evidenced as often assumed.

What is the suspected mechanism behind longer muscle length training leading to more hypertrophy?

While not fully known, a likely explanation is that longer muscle length training preferentially increases hypertrophy at more distal measurement sites (e.g., quads near the knee, biceps near the elbow). This might be due to these distal areas being activated more or contributing to greater force production during lengthened movements.

Should beginners use lengthened partials from the start?

There are arguments for and against. Teaching beginners a full range of motion initially provides a good foundation. However, studies comparing lengthened partials to full range of motion have predominantly included untrained participants. Given that long muscle length training doesn't require extra time and potentially offers better results, it could be beneficial for beginners.

What role does metabolic stress play in hypertrophy, especially with lengthened partials?

The role of metabolic stress is complex and not fully understood, but it's likely a contributor, not just independent of mechanical tension. Lengthened partials often keep muscles under constant tension, potentially leading to different metabolic effects compared to exercises with lockout. While mechanical tension is key, metabolic stimuli might modulate downstream hypertrophy signaling pathways.

Long Muscle Length Training with Dr. Milo Wolf (Episode 125)

Stronger By Science

Sports7 min read200 min video

Jan 24, 2024|4,098 views|130|27

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TL;DR

Dr. Milo Wolf discusses long muscle length training, highlighting its potential for superior hypertrophy, especially at distal muscle sites.

Key Insights

Longer muscle length training generally leads to more hypertrophy compared to shorter muscle length training, with consistent evidence across various muscle groups.

The hypertrophic benefits of longer muscle length training appear to be more pronounced at distal (further from the body's center) measurement sites within a muscle.

Specificity of training range of motion matters for strength and power outcomes; full range of motion generally offers better carryover to partial ranges than vice versa.

The precise mechanisms explaining the benefits of long muscle length training are not fully understood, but current leading theories (passive tension, stretch-induced sarcomerogenesis) lack definitive direct evidence.

Many common exercises, especially those that emphasize a stretched position under load like overhead triceps extensions or incline bicep curls, naturally incorporate long muscle length training.

Incorporating long muscle length training can be done through various methods, including lengthened partials, strategic exercise selection, tempo modifications, pauses in the stretched position, and integrated partials.

INTRODUCTION TO DR. MILO WOLF AND THE TOPIC

Dr. Milo Wolf, an expert in sport science, recently completed his PhD researching the effects of range of motion during resistance training on muscle hypertrophy and strength. His interest in this topic stems from the lack of clear consensus in existing literature and the practical application of full range of motion recommendations in training. This episode delves into his research and broader scientific understanding of long muscle length training, a method gaining popularity for its potential to enhance muscle growth.

EVOLUTION OF RANGE OF MOTION RESEARCH

In 2020, early research showed full range of motion was better for lower body muscle growth, but upper body studies were inconclusive (four lower body, two upper body). Dr. Wolf’s meta-analysis, conducted during his PhD, included 20-25 studies, expanding on previous work. Initially, it showed a trivial advantage for full range of motion in hypertrophy across all studies (effect size ~0.1). However, deeper subgroup analyses revealed more nuanced findings when considering specific muscle lengths during partial ranges of motion. The analysis categorized resistance training into full range of motion, partials at shorter muscle lengths, and partials at longer muscle lengths.

RANGE OF MOTION AND STRENGTH ADAPTATIONS

The research consistently showed that specificity applies to range of motion for strength and power. Training in a specific range of motion (full or partial) yielded better strength gains in that same range. Full range of motion training, however, provided better carryover to partial range of motion performance than the reverse. Interestingly, combining full range of motion with some partials was found to yield similar or slightly better strength gains compared to full range of motion alone, supporting practices already common among powerlifters.

HYPERTROPHY AND LONG MUSCLE LENGTH TRAINING

The key finding for hypertrophy was that when partials were performed at shorter muscle lengths, hypertrophy was inferior to full range of motion. Conversely, partials performed at longer average muscle lengths showed superior hypertrophy compared to full range of motion. This initial finding, though surprising to Dr. Wolf, aligned with a broader body of evidence (20-25 studies) consistently showing that training at longer muscle lengths is more effective for hypertrophy across various muscle groups and contraction types (isometrics and dynamic movements). The magnitude of this benefit is modest, estimated at 5-10% difference in growth, not revolutionary.

REGIONAL HYPERTROPHY AND ITS SIGNIFICANCE

A consistent pattern observed across studies is that longer muscle length training preferentially increases hypertrophy at more distal sites of a muscle (closer to its insertion point). For example, increased quad growth near the knee or biceps growth near the elbow. This phenomenon suggests that distal areas might be activated more or contribute more to force production during lengthened training. While surface EMG has been explored to measure this, its correlation with long-term hypertrophy is not always strong, especially between biomechanically dissimilar movements.

THE MECHANISMS BEHIND LENGTHENED TRAINING

Despite strong evidence for its efficacy, the precise mechanisms driving greater hypertrophy at longer muscle lengths remain largely unknown. Current theories often extrapolate from stretching studies (e.g., titan-related signaling, passive tension, sarcomerogenesis), but these are not directly supported by resistance training intervention studies that simultaneously measure mechanistic outcomes. Many studies showing increased hypertrophy at longer muscle lengths don't involve significant stretching, challenging the 'stretch under load' hypothesis as the sole explanation. Similarly, the 'total tension' theory (including passive tension) is partially challenged by studies on quads, where longer muscle lengths show more hypertrophy despite tension being higher at shorter lengths.

DEBUNKING THE SARCOMERE ADDITION THEORY

A common claim is that long muscle length training only increases muscle size by adding sarcomeres in series, thereby increasing muscle length. However, direct evidence from resistance training studies to support this is lacking. While some studies show increases in fascicle length, recent human research using biopsy analysis indicates that a significant portion of fascicle lengthening is due to the lengthening of existing sarcomeres, not just the addition of new ones. This highlights the complexity and ongoing research needed to fully understand muscle architectural adaptations.

SHORT-TERM VERSUS LONG-TERM EFFECTS

The question of whether the hypertrophic benefits of long muscle length training are a short-term 'novelty effect' or extend over longer durations (e.g., years) is currently unanswered due to a lack of long-term studies. Dr. Wolf believes that, without strong reasons to assume otherwise, the benefits observed over 3-4 months are likely to generalize over longer periods. He also critiques the 'novelty' argument as often being a convenient, unproven explanation to dismiss findings that contradict existing biases.

APPLICATION OF LENGTHENED PARTIALS TO VARIOUS MUSCLE GROUPS

The idea that certain muscle groups, like biceps and triceps, don't benefit from long muscle length training is often based on theoretical mechanistic assumptions rather than direct hypertrophy data. However, existing research (three studies on triceps, two on biceps) largely aligns with the general principle: long muscle length training provides similar or greater hypertrophy in these muscles, especially at their distal sites. While the data isn't extensive, it does not suggest these muscles are exceptions to the general trend.

PRACTICAL STRATEGIES FOR IMPLEMENTING LENGTHENED TRAINING

Individuals can incorporate long muscle length training in several ways:</p><ol><li>**Lengthened Partials:** Perform exercises only through the bottom, lengthened portion of the range of motion. This is particularly effective for exercises where the lengthened position typically lacks resistance.</li><li>**Exercise Selection:** Choose exercises that inherently challenge muscles more in their lengthened state (e.g., dumbbell pullover over cable pullover, incline dumbbell press for chest).</li><li>**Tempo Modifications:** Control the eccentric phase more deliberately and briefly pause in the stretched position, followed by an explosive concentric movement from that lengthened position.</li><li>**Lengthened Supersets:** Perform full range of motion sets to failure, then immediately follow with lengthened partials for additional overload.</li><li>**Integrated Partials:** Combine full range of motion reps with shortened partials within the same set, ensuring to finish with a full rep or at the point of full-rep failure for safety and effectiveness.</li></ol>

PAUSE SQUATS VERSUS BOUNCING AND METABOLIC STRESS

Regarding squats, pausing at the bottom of the squat (lengthened position) for growth is likely superior to bouncing out of the hole, despite bouncing allowing more weight. Pausing increases tension production in the lengthened position without necessarily maximizing load, aligning with principles of long muscle length training. Additionally, the role of metabolic stress in hypertrophy, often debated, might be a contributing factor. Dr. Wolf acknowledges its plausible influence on hypertrophy, especially in dynamic resistance training, even if it's not the primary 'initiator' of signaling cascades.

BEGINNERS AND LENGTHENED PARTIALS

Dr. Wolf suggests that while it's beneficial for beginners to learn full range of motion for general education, using lengthened partials early on is also reasonable. The research on lengthened training often includes untrained participants, indicating its applicability. He argues that it doesn't add significant complexity or time to training, and any potential future shift away from lengthened partials would be easy to implement (e.g., simply extending a squat to lockout).

THE 'NOVELTY' OF LENGTHENED PARTIALS

The intense discussion around lengthened partials, both positive and negative, is partly attributed to it being a 'new term' for practices reminiscent of old-school bodybuilding constant tension training. This phenomenon often elicits strong, immediate reactions. Dr. Wolf notes a current counterculture resisting 'evidence-based fitness' ideas, preferring traditional 'bro science.' He observes a cyclical nature in fitness trends, with science-oriented information ebbing and flowing in popularity every few years. The increased video-based content on social media further complicates nuanced scientific discussion.

Mentioned in This Episode

●Supplements

●Products

●Software & Apps

●Tools

●Companies

●Organizations

●Studies Cited

●People Referenced

Optimizing Hypertrophy with Long Muscle Length Training

Practical takeaways from this episode

Do This

Integrate lengthened partials into your training, especially for exercises where the lengthened position typically lacks tension (e.g., back, side raises, biceps).

Switch to exercises that inherently challenge muscles more at longer lengths (e.g., dumbbell pullover/fly over cable variations for chest/lats).

Control the eccentric phase more as you reach the longest muscle lengths in an exercise.

Briefly pause in the stretched/lengthened position.

Be explosive or forceful out of the lengthened position at the start of the concentric phase.

Utilize 'lengthened supersets' where you perform lengthened partials after a full range of motion set to failure.

For exercises with crushing risk (e.g., free squats, bench press), combine full reps with a few integrated partials, ensuring you end with a full rep or can just get one.

Avoid This

Don't solely focus on maximizing load by techniques that reduce time or force production in the lengthened state (e.g., bouncing out of a squat hole if hypertrophy is the goal).

Don't rigidly adhere to full range of motion if partials at longer muscle lengths prove more effective for specific muscle groups or exercises.

Don't expect revolutionary gains; the difference is likely small (5-10% in hypertrophy).

Don't neglect a general understanding of full range of motion, especially for beginners.

Common Questions

Dr. Wolf's interest stemmed from reading a systematic review by Brad Schoenfeld and Joseph Grgic, which highlighted a lack of consensus and evidence in range of motion effects on hypertrophy, particularly in the upper body. He also noted that common recommendations for full range of motion lacked solid backing, prompting him to investigate.

Topics

Muscle Length Training Mechanisms Fitness Research Workout Techniques

Mentioned in this video

personJoseph Grgic

Co-author of a systematic review on range of motion and muscle hypertrophy, cited by Milo Wolf.

toolPrime machine

A niche piece of gym equipment that allows for biasing the lengthened position, potentially negating the need for lengthened partials.

personJay Cutler

A famous bodybuilder mentioned in the context of the 'bros' doing lengthened partials for years, as a counter-argument to new scientific findings.

studyPinto et al. study

A study on curls mentioned in the context of upper body range of motion research, showing mixed results.

studyWorkman et al. study

An 'underrated classic' study that had participants perform a super partial range of motion knee extension on the leg press.

studyStasinaki et al. triceps study

A study comparing overhead extensions (lengthened) to push-downs (shortened) for triceps hypertrophy, which found no significant difference, though nominal differences leaned towards overhead extensions. Conflicting results with muscle thickness vs. cross-sectional area.

studyKubo et al. study

A squat study comparing 0-120° knee flexion to 0-90° for quad growth, which found similar hypertrophy between the groups, challenging the idea that maximal length is always superior for hypertrophy.

supplementHydroxyapatite

A chemical found in some toothpastes (also mineral name for calcium phosphate) that can help plug micro-fissures from tooth decay. Originally developed by NASA.

studyWakahara et al. studies

A line of research (potentially confused with Ogasawara) looking at activation via transverse relaxation MRI and its relationship to regional hypertrophy during different exercises.

organizationSouthampton Solent University

Where Milo Wolf pursued and completed his PhD in Sport Science, focusing on range of motion in resistance training.

studyPedrosa et al. quad study

A study referenced for specific muscle length comparisons, particularly on quadriceps hypertrophy with partials.

studyPedrosa et al. biceps study (second study)

This study compared the same range of motion in preacher curls, performed at different muscle lengths (bottom half vs. top half reps). It found more favorable hypertrophy in the bottom-half group at the more distal site.

supplementCalcium Phosphate

The main mineral composing teeth, also known as hydroxyapatite.

studyMaio et al. hamstring curl study

A study that compared the same range of motion (knee flexion) at different muscle lengths (seated vs. lying leg curl), influencing hamstring and other biarticular muscle lengths.

studyOgasawara et al. studies

A line of research (potentially confused with Wakahara) looking at activation via transverse relaxation MRI and its relationship to regional hypertrophy during different exercises.

studySato et al. study

A study on unilateral bicep curls comparing two different partial ranges of motion (long vs. short muscle length), finding more hypertrophy with long muscle length training, especially distally.

studyCassano et al. study

A study comparing different calf raise variations (full, shortened partials, lengthened partials with extended knees) which found more gastrocnemius hypertrophy with lengthened partials.

personKai Greene

A bodybuilder known for emphasizing 'constant tension' during exercises, a concept similar to lengthened partials. Mentioned during discussion of how new terms are perceived.

productDr. Jyn's Superpaste

A specific brand of toothpaste containing both fluoride and hydroxyapatite, recommended by the host.

organizationMonthly Applications in Strength Support (MASS)

A research review for strength and physique athletes and coaches, providing updates on relevant scientific literature.

softwareGenius (Disney+ series)

A Disney+ series about important historical figures, with season one focusing on Albert Einstein.

personMileva Marić

Albert Einstein's first wife, a physicist, whose struggles with mental health and 'housewife roles' were portrayed as reasons for their marital issues in the 'Genius' series.

studyPallarés et al. study

A previous meta-analysis on range of motion for hypertrophy that only looked at lower body findings and found a larger difference in favor of full range of motion.

studyPinchera et al. study (2021/2022)

A study that looked at Nordic curls' effect on fascial length and took biopsies to measure sarcomere length, finding that observed fascial lengthening was primarily due to increases in resting sarcomere length, not sarcomeres in series.

personBill Pearl

A bodybuilder mentioned to highlight that concepts similar to lengthened partials have existed in physical culture for decades.

studyPlotkin et al. study

A study that compared squats to hip thrusts, measuring hypertrophy and EMG of different muscle areas, finding little correlation between baseline EMG and hypertrophy.

studyZabaleta et al. study

A study comparing incline curls to preacher curls to inform biceps muscle length effects.

studyDamas et al. study (2019)

A study that compared a constant resistance training program to one with constant changes, considered by some as not a perfect test of the 'novelty' hypothesis.

studyGoo et al. study

A study on curls mentioned in the context of upper body range of motion research, which showed mixed results concerning hypertrophy.

conceptfluoride

organizationRenaissance Periodization