THE REAL REASON MOST LIFTERS DON’T BUILD MUSCLE USING PARTIALS REPS & HOW TO FIX YOUR PARTIAL REPS TO START GROWING (PART 2)

 

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THE REAL REASON MOST LIFTERS DON’T BUILD MUSCLE USING PARTIALS REPS & HOW TO FIX YOUR PARTIAL REPS TO START GROWING (PART 2)

• Partial reps at long muscle lengths can build muscle similar to a full contraction
• Stretching a muscle at full length is a potent stimulus for muscle growth.
• Keep stretching before exercise to less than 20 seconds.
• Do Not Stretch to the point of intense pain before exercise.
• Dynamic warmups such as arm swings, walking lunges, and walking knee raises are effective ways to warm up.
• Stretching the muscle between sets may increase muscle growth, but more research is needed.

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THE BENEFITS OF A STRETCHED MUSCLE FOR MUSCLE GROWTH

You want to stretch the muscle as far as possible without pain; stretching the muscle can increase anabolic signaling pathways independent of tension.[1] Certain animal studies have shown that you can increase muscle growth by stretching a muscle with tension.

The greater stretch of the hamstrings induced by seated leg curls results in more hamstrings growth than lying leg curls.[2] This same concept can explain why deep squats grow the glutes more than shallow squats because deep squats stretch the glutes more.[3] A recent 2021 study found that stretching the hamstrings before and during rest periods between squats increased hamstring growth. The non-stretching group showed no increases in hamstring growth.[4]

The further the resistance or weight is away from a joint, the greater the tension your muscles will need to generate to overcome the resistance and weight lifted (longer muscles have a reduced ability to generate force). Remember that the combination of tension and stretching a muscle optimizes muscle growth.

Doing a partial rep without a fully stretched muscle is not conducive to muscle growth. The current research indicates that passive, low-intensity stretch does not result in beneficial changes in muscle growth. However, the research suggests intense stretch training may stimulate muscle growth, particularly with weights or added between active muscle contractions.[5]

This suggests that tension and muscle stretch are necessary for muscle growth. A meta-analysis of 26 studies found that isometric contractions in the stretched position increased muscle growth more than in a contracted position.[6] Hold the muscle in a stretched position and contract the muscle. For example, doing a leg curl and contracting the muscle while stretched.

STRETCHING PLUS TENSION

Stretching alone will not greatly impact muscle growth; otherwise, we would see jacked yoga instructors everywhere. For example, one study had subjects complete a static stretching program for six weeks with calf stretches. The groups stretched their calves once per week or three times per week.

At the end of the study, neither muscle strength nor muscle size was changed regardless of the stretching frequency.[7] It’s the combination of tension and stretch that increases muscle growth. If you experiment with partial reps, include them in workouts that use a full range of motion.

A 2004 study found that full and partial squats resulted in a greater squat increase than just using a full range of motion.[8] As noted above, some preliminary evidence suggests that partial reps with the muscle in a stretched position were as effective as full repetition. Experiment with doing a few sets of a full range of motion, and in your last set, when you are fatigued, use one set of partial reps in the stretched position. It may cause more muscle growth.

Keep in mind that you should not be performing an excessive range of motion by performing an exercise. Your range of motion should be done safely and feels comfortable to you. If, while doing the movement, you feel an excessive strain on your joints, then reduce the range of motion to where it becomes comfortable.

The excellent news for people who don’t like to stretch is that resistance training is comparable to passive stretching for increasing joint range of motion.[9] There are benefits to incorporating partial reps into your strength training workouts. Partials are great for improving sticking points, so incorporating partials a few times a week is a great way to maximize your strength training exercises.

IS STRETCHING BEFORE WORKOUTS GOING TO KILL YOUR MUSCLE GROWTH GAINS?

For years it was suggested that static stretching could reduce muscle soreness. However, a literature review concluded that stretching does not reduce soreness, regardless of whether the stretching is performed before or after the training bout.[10]

There has been an anti-stretching campaign because a few studies have shown that stretching before exercise can reduce performance. It has been found that static stretching before exercise can reduce strength training, reduce repetitions completed, and even reduce muscle growth compared to those that do not stretch before exercise.[11]

The rubber band analogy is the most common way of thinking about how stretching too long can affect your power production. If you stretch a rubber band and let it go, it recoils, but if you stretch it back for an extended period, it loses its recoil ability and will not fly forward as far.

The same principle applies to stretching for prolonged periods before exercise. Two factors determine whether stretching before a workout can decrease performance: duration and the intensity of the stretch.

Partial Reps Studies

Studies suggest that holding a static stretch for less than a minute is not detrimental to performance.[12] 60 seconds is the max upper limit. Most experts would probably recommend less (<10 seconds). The research on stretching may not apply to real-world lifting because most studies have subjects stretch and immediately perform an exercise.

Most people don’t stretch and then immediately perform a set of exercises. Studies have shown that if you stretch and then wait ten minutes, there is an increase in performance.[13] Short-duration stretching for 20 seconds had no impact on reducing performance.[14]

Also, the studies that have found that stretching reduces performance have used static stretching to the point of pain (85% pain), whereas stretching with low-intensity stretches (50% pain) has shown no reductions in performance.[15] If the stretches are short and low intensity, there will be minimal effects on performance.

Stretching Intensity

Low-intensity stretching has been found to improve recovery, possibly by increasing blood flow to the muscle.[16] A recent study divided men into three groups: a.) Static stretching, b.) dynamic stretching, and c.) control group. The static stretching group performed 2 different stretches for 2 sets of 20 seconds (i.e., a total of 80 seconds of stretching). In contrast, the dynamic stretch group performed 15 repetitions by moving their limb continuously through a challenging range of motion.

Both groups stretched to a mild discomfort level. At the end of the study, all groups reported similar increases in muscle growth and strength.[17] The key point is that the subjects did not overly stretch their muscles (i.e., <20 seconds for each stretch) and kept the discomfort level at a 5. The studies found stretching interfered with muscle growth stretched before exercise, with a pain value between 8 and 10, and stretched for 30 seconds.[18]

The best way to stretch is to perform either static or dynamic warm-ups, in which you “move while stretching.” An example would be squatting up and down with no weight before squats getting a full range of motion, or a walking lunge would be another form of a dynamic warmup. It’s also been found that dynamic stretching after static stretching can counteract the adverse effects of static stretching.[19]

EXPERIMENT WITH LOW-INTENSITY STRETCHING BETWEEN SETS

Many people do a set and then rest, sitting and doing nothing. Several studies have found that stretching the opposite muscle group you exercise can increase performance.[20,21]

For example, stretching the back while training the chest and stretching the hamstrings while doing leg extensions. Two studies have shown that stretching between sets may be beneficial. In one study, subjects either rested between sets or stretched between sets. The stretching consisted of low-intensity, low-pain stretching between sets for 30 seconds.

At the end of the study, there was a trend for greater muscle growth for the legs, whereas the other body parts did not benefit.[22] The other study found that stretching the calves between sets leads to greater muscle growth.[23]

Contrary to this, a study that had subjects stretch between sets found no difference in muscle growth in the chest.[24] There is no concrete proof that stretching between sets will increase muscle growth, but it certainly won’t hurt as long as the stretches are low-intensity and don’t cause pain.

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KEY POINTS

• When weight training for muscle hypertrophy, it’s best to train with long muscle lengths.
• When performing bodyweight exercises to build strength, such as push-ups, use a full rep that maximally stretches the chest muscle by placing your arms on elevated blocks.
• Free weight allows for a greater range of motion and greater muscle stretch.
• Partial reps seem to work best for the arms, not the legs.
• Most research supports using a full range of motion that maximally stretches the muscle for muscle growth.
• Stretching a muscle at full length is a potent stimulus for muscle growth.
• Keep stretching before exercise to less than 20 seconds.
• Do Not Stretch to the point of intense pain before exercise.
• Dynamic warmups such as arm swings, walking lunges, and walking knee raises are effective ways to warm up.
• Stretching the muscle between sets may increase muscle growth, but more research is needed.

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REFERENCES

1.     David W. Russ, “Active and Passive Tension Interact to Promote Akt Signaling with Muscle Contraction,” Medicine and Science in Sports and Exercise 40, no. 1 (January 2008): 88–95.

2.     Sumiaki Maeo et al., “Greater Hamstrings Muscle Hypertrophy but Similar Damage Protection after Training at Long versus Short Muscle Lengths,” Medicine and Science in Sports and Exercise 53, no. 4 (April 1, 2021): 825–37.

3.  Keitaro Kubo, Toshihiro Ikebukuro, and Hideaki Yata, “Effects of Squat Training with Different Depths on Lower Limb Muscle Volumes,” European Journal of Applied Physiology 119, no. 9 (September 2019): 1933–42.

4.  Thiago Barbosa Trindade et al., “Pre-Stretching of the Hamstrings Before Squatting Acutely Increases Biceps Femoris Thickness Without Impairing Exercise Performance,” Frontiers in Physiology 11 (2020): 769.

5.  João Pedro Nunes et al., “Does Stretch Training Induce Muscle Hypertrophy in Humans? A Review of the Literature,” Clinical Physiology and Functional Imaging 40, no. 3 (May 2020): 148–56.

6.  Dustin J. Oranchuk et al., “Isometric Training and Long-Term Adaptations: Effects of Muscle Length, Intensity, and Intent: A Systematic Review,” Scandinavian Journal of Medicine & Science in Sports 29, no. 4 (April 2019): 484–503.

7.  Shigeru Sato et al., “The Effects of Static Stretching Programs on Muscle Strength and Muscle Architecture of the Medial Gastrocnemius,” PLOS ONE 15, no. 7 (July 9, 2020): e0235679.

REFERENCES

8.  Caleb D. Bazyler et al., “The Efficacy of Incorporating Partial Squats in Maximal Strength Training,” Journal of Strength and Conditioning Research 28, no. 11 (November 2014): 3024–32.

9.  José Afonso et al., “Strength Training versus Stretching for Improving Range of Motion: A Systematic Review and Meta-Analysis,” Healthcare 9, no. 4 (April 2021): 427.

10.  Robert D. Herbert, Marcos de Noronha, and Steven J. Kamper, “Stretching to Prevent or Reduce Muscle Soreness after Exercise,” The Cochrane Database of Systematic Reviews, no. 7 (July 6, 2011): CD004577.

11.  Roberto Moriggi Junior et al., “Effect of the Flexibility Training Performed Immediately before Resistance Training on Muscle Hypertrophy, Maximum Strength and Flexibility,” European Journal of Applied Physiology 117, no. 4 (April 2017): 767–74.

12.  Anthony D. Kay and Anthony J. Blazevich, “Effect of Acute Static Stretch on Maximal Muscle Performance: A Systematic Review,” Medicine and Science in Sports and Exercise 44, no. 1 (January 2012): 154–64.

13.  Evan Peck et al., “The Effects of Stretching on Performance,” Current Sports Medicine Reports 13, no. 3 (June 2014): 179–85.

14.  João B. Ferreira-Júnior et al., “Effects of Static and Dynamic Stretching Performed Before Resistance Training on Muscle Adaptations in Untrained Men,” Journal of Strength and Conditioning Research, September 17, 2019.

REFERENCES

15.  Paulo H. Marchetti et al., “Different Volumes and Intensities of Static Stretching Affect the Range of Motion and Muscle Force Output in Well-Trained Subjects,” Sports Biomechanics, August 29, 2019, 1–10.

16.  Nikos C. Apostolopoulos et al., “The Effects of Different Passive Static Stretching Intensities on Recovery from Unaccustomed Eccentric Exercise – a Randomized Controlled Trial,” Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquee, Nutrition Et Metabolisme 43, no. 8 (August 2018): 806–15.

17.  João B. Ferreira-Júnior et al., “Effects of Static and Dynamic Stretching Performed Before Resistance Training on Muscle Adaptations in Untrained Men,” Journal of Strength and Conditioning Research, September 17, 2019.

18.  Roberto Moriggi Junior et al., “Effect of the Flexibility Training Performed Immediately before Resistance Training on Muscle Hypertrophy, Maximum Strength and Flexibility,” European Journal of Applied Physiology 117, no. 4 (April 2017): 767–74.

19.  Iain M. Fletcher and Bethan Jones, “The Effect of Different Warm-up Stretch Protocols on 20 Meter Sprint Performance in Trained Rugby Union Players,” Journal of Strength and Conditioning Research 18, no. 4 (November 2004): 885–88.

20.  Humberto Miranda et al., “Acute Effects of Antagonist Static Stretching in the Inter-Set Rest Period on Repetition Performance and Muscle Activation,” Research in Sports Medicine (Print) 23, no. 1 (2015): 37–50.

21.  G. Paz et al., “Strength Performance Parameters and Muscle Activation Adopting Two Antagonist Stretching Methods before and between Sets,” Science & Sports 31, no. 6 (December 1, 2016): e173–80.

REFERENCES

22.  Alexandre L. Evangelista et al., “Interset Stretching vs. Traditional Strength Training: Effects on Muscle Strength and Size in Untrained Individuals,” Journal of Strength and Conditioning Research 33 Suppl 1 (July 2019): S159–66.

23.  Simpson et al., “Stretch Training Induces Unequal Adaptation in Muscle Fascicles and Thickness in Medial and Lateral Gastrocnemii.” Scandinavian journal of medicine & science in sports, 27(12), 1597–1604.

24.  Tanuj Wadhi et al., “Loaded Inter-Set Stretching for Muscular Adaptations in Trained Males: Is the Hype Real?,” International Journal of Sports Medicine, August 10, 2021.

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